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L’acide oxalique est un ligand mis en avant pour la récupération quantitative des actinides séparés des produits de fission. En particulier, la co-précipitation oxalique facilite l’incorporation des actinides mineurs dans des matériaux céramique dédiés à leur transmutation grâce à la formation contrôlée de composés oxalate mixtes, précurseurs des solutions solides oxyde souhaitées. Les méthodes de croissance cristalline existantes n’étant pas adaptables à la chimie du système actinide-oxalate et aux conditions de manipulation en boîte-à-gants, plusieurs méthodes de synthèse originales ont été conçues puis développées sur les lanthanides et les actinides légers (uranium, thorium). Quatre méthodes originales, basées sur des stratégies de mise en contact lente des réactifs, ont ainsi été optimisées. Après développement sur les simulants, elles ont été adaptées aux spécificités (notamment redox) des actinides plus lourds tels le plutonium ou l’américium. Elles ont permis la synthèse de nombreux monocristaux d’oxalates d’actinide et d’oxalates mixtes An1(IV)-An2(III) mais aussi An1(IV)-An2(IV). Finalement, les premières caractérisations structurales poussées de ces composés par DRX sur monocristal, EXAFS ou micro-RAMAN permettent d’acquérir des informations structurales indispensables à l’enrichissement de la base de données structurales relativement pauvre concernant les oxalates d’actinides. Cette dernière est pourtant indispensable à une meilleure compréhension des futurs cycles du combustible actuellement à l’étude. / Oxalic acid is a well-known reagent to recover actinides thanks to the very low solubility of An(IV) and An(III) oxalate compounds in acidic solution. Therefore, considering mixed-oxide fuel or considering minor actinides incorporation in ceramic fuel materials for transmutation, oxalic co-conversion is convenient to synthesize mixed oxalate compounds, precursors of oxide solid solutions. As the existing oxalate single crystal syntheses are not adaptable to the actinide-oxalate chemistry or to their manipulation constrains in gloves box, several original crystal growth methods were developed. They were first validate and optimized on lanthanides and uranium before the application to transuranium elements. The advanced investigations allow to better understand the syntheses and to define optimized chemical conditions to promote crystal growth. These new crystal growth methods were then applied to a large number of mixed An1(IV)-An2(III) or An1(IV)-An2(IV) systems and lead to the formation of the first original mixed An1(IV)-An2(III) and An1(IV)-An2(IV) oxalate single crystals. Finally thanks to the first thorough structural characterizations of these compounds, single crystal X-ray diffraction, EXAFS or micro-RAMAN, the particularly weak oxalate-actinide compounds structural database is enriched, which is essential for future studied nuclear fuel cycles.

Malaysian Farmers' Organisations (FOs) strive to achieve both social and economic objectives. However, the achievement of economic objectives are often emphasised in appraising their performance. Thus, many FOs tend to be categorised as poor-performing. To identify factors influencing farmers' behaviour towards FOs, and factors affecting FO financial performance, solvency and self-financing potential, this study utilised data from a survey conducted on 418 farmers, statistical reports of the Farmers' Organisation Authority, and the 1985 and 1986 Auditor's Reports on 149 FOs in Peninsular Malaysia. Two logit models indicated that members' familiarity with FO officials is the most significant variable influencing positively farmers' decisions to join and subsequently to support FOs. One way to attract many non-members who indicated their willingness to join FOs is by easing the procedure for membership. Although total FO assets had increased markedly since 1973, members' paid-up share capital only financed about 11 per cent at the end of 1986. Accumulated profits and statutory reserves had contributed significantly to the growth of FO equity capital. However, the poor collectability of accounts receivable had an adverse effect on FO liquidity positions. A log-linear regression model indicated that stock turnover, assets per share, business diversification, per member administrative expense and the ratio of cash to current liabilities significantly affected FO financial performance. A semilog regression model indicated that FOs solvency positions were positively affected by sales per member, and negatively by the ratio of operating expense to operating income, percentage of bad debts, stock turnover and the ratio of current assets to paid-up shares. The total incomes of most FOs in 1986 were lower than their estimated break-even volume of business, mainly due to low gross margin rates resulting from high rates of operating expense and/or low mark-up. Thus, about 12 per cent of FOs have the potential to become self-financing.

Self-regulated learning (SRL) processes are frequently used by elite athletes and are thought to be an important factor in the development of expertise (McCardle, Young, & Baker, 2017). Before learners become self-regulated, they must first be co-regulated by a more experienced other (Glaser, 1996), such as an instructor. Scaffolding, a form of co-regulation, has three conceptual characteristics: contingency, fading, and transfer of responsibility (van de Pol & Elbers, 2013). Of the little research done on scaffolding, most studies have been in the education domain with few looking at it in a naturalistic setting. This thesis represented a seminal investigation on the nature of scaffolding in a coach-athlete dyad. It aimed to explore scaffolding using a naturalistic, instrumental case study with an experienced female coach (aged 53, national level) and her competitive male figure skater (aged 15, provincial level) using a concurrent mixed methods design (Creswell, 2003). Data were collected through a) an athlete self-report survey on SRL at the beginning and end of data collection; b) participant observation, field notes, and audio recordings of coach-skater dialogue at 16 practices spread across 5 months of the season; and c) three separate interviews at mid-, late-, and post-season with the coach and skater. Study 1 presents results informed by the skater’s survey and quantitative analyses of audio transcripts. The skater’s self-report of the SRL-SP (Bartulovic, Young, & Baker, 2017) was higher at time two (post-season) compared to time one (mid-season), indicating an increase in SRL. Due to very poor reliability uncovered in pilot work, planned analyses to determine changes in the directionality of coach- and skater-initiated discussion and contingency at various points across the season could not be performed. Study 2 presents the results of thematic analysis (Braun & Clarke, 2006) on the interview data and audio transcript excerpts. Deductive analyses showed it was difficult to identify and describe aspects of the three scaffolding characteristics separately due to their overlapping conceptual definitions, and their interplay during practice. Inductive analyses revealed nuances of scaffolding in sport, including micro- and macro-level co-regulation. Micro-level co-regulation emerged as an important “interface” illustrated by mature coach-skater interactions surrounding practice trials. The interface involved shared and individual expectations for the coach and skater, roles, and described transitory processes relating the co-regulatory interface to the skater’s SRL. Fading in sport differed from the linear model in education with a cyclical pattern of engagement by the coach, returning to refine the skater’s elements if they were incorrect. After integrating and interpreting all the data, the findings suggested scaffolding manifests in unique ways in a sport dyad, with SRL representing a process goal of the interface.

<p>I dag när biobränsle används i allt större utsträckning och uttagen från skog har ökat finns ett behov av att använda restprodukten från förbränning, askan, till skogsmarkerna. Askan från förbränning av trädbränsle innehåller, förutsatt att den är väl utbränd, många näringsämnen och har ett högt pH, därför kan den användas för att återföra näringsämnen till skogen och minska försurning i marker.</p><p>Vid förbränning av träpulver tillsätts svavel för att minska CO-utsläppen till luft. Syftet med denna studie var att undersöka hur svavel påverkar flygaskans kvalité. Är det någon skillnad i halten oförbränt kol och PAH-halt i askan när svavel har tillsatts i bränslet, och hur stor påverkan har syre på halten oförbränt kol och PAH-halten.</p><p>Det insamlades tolv referensprover för att se den normala variationen av halten oförbränt kol i flygaskan under en tolvdagarsperiod. Därefter samlades ytterligare 14 prover in under hög/låg syrehalt och med eller utan svavel. På tio av dessa prover analyserades 16 PAH, och på alla prover analyserades halten oförbränt kol. Halten oförbränt kol analyserades med glödgningsförlust enligt SS 18 71 87. 16 PAH analyserades genom mätning med GS-MS.</p><p>Resultaten visar att det är generellt mycket höga halter oförbränt kol i askproverna och det ger en sämre aska för återföring. Hög syrehalt i förbränningskammaren ger en signifikant lägre halt oförbränt kol i askan. PAH-halten tyder på en ökning i samband med ökad halt oförbränt i askan. Tillsatser av svavel till bränslet verkar ge som effekt att halten oförbränt i askan minskar.</p> / <p>Today with the increase in biofuel use and the removal of wood from the forest, there is an increased need for recycling the ash from combustion back to the forest. Ash from combustion of wood contains many nutrients and has a high pH and therefore can be used to restore nutrients to the forest and to reduce acidification of the ground.</p><p>Sulphur is induced to the combustion of wood-powder in order to reduce emissions of CO to the air. The purpose of this study was to examine how the induction of sulphur to the fuel affects the quality of the fly ash, if there is a difference in loss on ignition, if the PAH-content is affected of the admixture of sulphur in the fuel and how significant is the effect of the oxygen content in the combustion.</p><p>Twelve reference samples were collected during a twelve-day period to see the normal variation of the loss on ignition. Then another 14 samples were collected under high/low oxygen content and with or without sulphur. On ten of the samples 16 PAH:s were analysed, and the loss on ignition was analysed on all samples. Loss on ignition was analysed according to the SS 18 71 87. Sixteen PAH:s were analysed by measuring with GS-MS.</p><p>The results show that there is a generally high loss on ignition on all of the ash samples and that results in a lower quality ash for recycling. Oxygen content has a significant effect on the loss on ignition in the ash and high oxygen content in the combustion chamber gives a lower loss on ignition. PAH content indicate an increase in connection with an increased loss on ignition. Admixture of sulphur to the fuel indicates that the loss on ignition in the ash decreases.</p>

The farm-retail price spread is the difference between the retail price of a product and its farm value. It changes with changes in factor prices, the efficiency of providing services, and the quantity and quality of services embodied in the final product. A model was derived by Box-Cox transform base on the relative price spread mode for the U.S. pork industry. The new model analyses the determinant of margins more accurately. The results indicate the log of farm-retail price spread is significantly and positively related to increases in log of retail price and log of quantity of farm input. And the relationship between the price spread and industry costs is indeterminate. The results point to the strong possibility of spurious correlation between the price spread and concentration variables. It suggests other possibly unobserved variables correlated with trend are spuriously indicating concentration ratio, has a significant effect on the price spread. Another major implication of this study is that variables used on the regression need to be detrended in estimation.

Quantitative trait loci (QTL) mapping in outbred populations faces some challenges unique to the divergent genetic background and complex pedigree relationships. Motivated by a dairy cattle half-sib data set from a grand daughter design, we present in this dissertation a series of endeavors to address various challenges along the analysis flow of QTL mapping. A first step is to infer the haplotypes in sires based on the observed genotypes in sires and his offspring. Our method was shown to outperform peer methods with greater robustness and accuracy yet with fast speed performance. Then in light of adapting the multiple interval mapping method to within-family QTL analysis, we extended the modeling framework by allowing for heteroscedastic residual variances and upgraded the Windows QTL Cartographer accordingly. The advantageous post-analysis result parsing from Windows QTL Cartographer and more importantly, the improved analysis outputs due to more powerful maximum likelihood-based mixture modeling than the least squares regression manifest our efforts in delivering better methodology via practically user friendly software. We further developed a mixed model approach for the purpose of QTL mapping across multiple families that was aimed at modeling QTL effects as both the fixed effect across families and the random effect within families. Our mixed model was shown to encompass similar or higher statistical testing performance on QTL variation than the widely used variance component modeling approach, yet still allowing permutations for obtaining chromosome-wide or genome-wide significance threshold. What's more, the flexibility of our mixed model in constructing alternative hypotheses testing on either fixed or random QTL effects or both was shown to offer interesting insight into the varying sources of signal that would not be unveiled by least squares regression or variance component methods. In concluding our comprehensive approach to QTL linkage mapping in dairy cattle populations, we continue to explore methods of fine mapping by combining both the linkage disequilibrium and linkage information and prospective method improvements are being sought.

In recent years population-based association studies have been advocated as the most powerful method of discovering genetic loci that are associated with heritable traits, particularly for complex traits that are likely caused by a variety of factors including environmental effects and multiple genetic loci. Genome-wide association studies (GWAS) have already yielded a large number of such associations, but there is growing concern that the results of these studies are not explaining as much genetic variation as they were expected to. Chapter 2 discusses tagging and imputation to leverage the information available on commercial genotyping chips to make inferences about variants found in large reference samples such as those made available by the International HapMap Consortium. Transferability of multi-marker tagging is assessed. Tagging and imputation are compared, and a method of using tagging to select a reduced tag set to be used for imputation. Chapter 3 details how multiple low frequency causal variants can create synthetic associations among more common variants and may be responsible for many of the genome-wide associations that have already been observed. Examples of synthetic associations are demonstrated in congenital deafness and sickle-cell anemia. Chapter 4 examines issues related to combining samples of diverse genetic ancestry for analysis in genetic association studies. Through simulation it is shown that type I error can be controlled and power increased using statistical methods to account for differences in populations.

This is a study to understand and interpret the governance structure of and the pattern of development followed by farmer co-operatives in China. China's farmer co-operatives have developed rapidly since the Farmers Co-operative Law came into force in 2007. Unlike their counterparts in western democratic capitalist systems, however, farmer co-operatives in China are owned and controlled by individuals and groups other than farmers -- the resulting structure is referred to as the Company+Household (C+H) co-operative. As a result, the small farmers who make up the majority of members have very little participation or control in these organizations. This thesis also uses the development of farmer co-operatives as a lens through which Chinese agriculture and rural development can be viewed and understood. The proposition examined in the thesis is that the pattern of co-operative development is the expected outcome given the challenges that China is facing in its agricultural sector, China's economic development goals, and the political economy of the country.<p> The thesis examines the governance structure -- i.e., the way in which business entities are structured and controlled -- of C+H cooperatives using political economy theories. This theory argues that corporate governance structures reflect public policy choices. These policy choices are fundamentally the result of political decisions, decisions that are heavily influenced by the preferences and power resources of different groups in a society, as well as by the existing political and economic institutions. China's political economy shapes ``a capitalism with Chinese characteristics.' All capitalist systems require mechanisms that coordinate decisions and expectations. Due to a lack of institutionalized trust (e.g., trust created by reliance on the rule of law and independent judiciaries), China relies on other mechanisms for this coordination. Meanwhile, minority shareholder protections (e.g., auditing and disclosure rules) are virtually absent. The outcome is an economic system in which a blockholder ownership pattern emerges as the most effective governance structure, with the state and large investors (both of which have close personal ties to other investors and other state officials) as the blockholders. Within this system, there is little room for the small investor. Consequently, China's political economy provides an environment in which farmer co-operatives that are owned and operated by small farmers, and in which the state and large private interests are largely absent, would be very unlikely to exist.<p> The thesis also uses industrial organization theory to analyze C+H co-operatives in the context of agricultural industrialization. The argument developed in this thesis suggests that C+H cooperatives have also emerged as the most likely organizational structure for reasons unique to the agricultural sector. Specifically, the industrialization that has occurred in agriculture around the world during the last two decades has created a need for much greater coordination within agricultural supply chains as companies within this chain attempt to provide a rapidly increasing range of products that must meet increasingly higher standards of consistency, quality and safety. Therefore, agro-processors increasingly specify the type and quality of product produced by farmers, who are often contractually required to buy inputs from and to sell output to a particular processor.<p> A key outcome of the research in this thesis is that the development of farmer co-operatives has to be seen as an endogenous response to the political and economic interests operating in China at the time the co-operative law was introduced. The beliefs and associated behaviours of those that benefit from the emergence of this particular policy helped to enforce and reinforce the emergence of new organizational forms that further perpetuate the power of those that initially benefitted. This self reinforcement (i.e., positive feedback) creates path dependency, which in turn explains the persistence of high modernism, capitalism with Chinese characteristics and patron-client structures, all of which contributed to formation of C+H cooperatives. The C+H co-operatives not only have a governance structure that fits into the political structure, but they provide a large degree of control by the company (i.e., the agro-processor) over the decisions made by farmers, which are crucial to meet the coordination needs of modern supply chain. The conclusion is that the political and economic institutions in China today do not provide an enabling environment for the establishment and the success of farmer self-help groups. As a consequence of both China's larger political economy and the conditions specific to agriculture, it is to be expected that the C+H model of a co-operative has emerged as the dominant organizational form for co-operatives in China.

Poverty alleviation strategies