488 research outputs found
CONTRIBUTION TO LINKAGE AND ASSOCIATION MAPPING OF TRAIT LOCI IN LIVESTOCK.
Until recently, breeding values were estimated based on phenotypes measured on the individual and its relatives, and the notion that the covariance between breeding values is proportionate to the kinship coefficient. Advances in genomics now allow for direct analysis of the genome and identification of the loci that determine the breeding values of individuals. As a consequence, marker assisted selection and genomic selection have become more effective and are replacing conventional selection.
The identification of loci influencing the traits of interest requires the use of advanced statistical methods that are constantly evolving. In the context of this thesis, we have (i) contributed to the development of gene mapping methods, (ii) applied these methods to map loci influencing both metric and meristic traits, and (iii) contributed to the development of methods for the integration of genomic information in livestock breeding and management.
The mapping methods that we have helped developing distinguish themselves mainly by the fact that (i) they exploit haplotype information (by means of a hidden markov model) which should increase the linkage disequilibrium with causative variants and hence detection power, (ii) they can simultaneously extract linkage information within families, and linkage disequilibrium information across the population, and (iii) they correct for population stratification by means of a random polygenic effect, and (iv) they can be applied to binary as well as quantitative traits.
We have applied these and other methods to map loci influencing (i) quantitative hematological parameters in a porcine line-cross, and (ii) binary traits including diseases in bovine and non-syntenic Copy Number Variants in cattle, horse and human.
In fine, we have contributed to the development of methods for the utilization of marker information in animal selection and production. We have extended the haplotype-based mapping method to allow imputation and have evaluated the utility of this approach in scenarios mimicking reality. We have also contributed to the development of a method to quantify somatic cell counts in the milk of individual cows by genotyping a sample of milk from the farm’s tank (hence a mixture of milk from all cows on the farm)
Our work has resulted in the development of a software package (“GLASCOW”) that is increasingly used by the community to map genes influencing complex traits, primarily binary. By using this tool, we have contributed to the localization of several trait loci in pig, cattle, horse and human. We have contributed to the development of approaches that reduce the costs of genomic analyses in livestock by, on the one hand, complementing real SNP genotypes with genotypes obtained in silico by means imputation, and, on the other hand, by developing a method to deconvolute genotypes obtained on DNA pools
Fluid and Loci: Death and Memory in Shakespearean Plays
This study combines formal analysis of Shakespeare’s texts with an investigation of early modern English culture in order to explore the social energy circulating between. It argues that the conceptual categories of fluidity and loci are two features prevalent not only in Shakespeare’s plays specifically, but also in early modern English culture generally. Chapter One maps out the scholarship on death and memory in early modern English culture; Chapter Two investigates fluidity and loci in numerous forms, including humoral bodies, identities, money, commodity and texts, as regards physiology, economics, cosmology and politics. Chapter Three on Hamlet investigates corruption and fragmentation regarding both death and memory, and it also argues that Hamlet is troubled by memory’s excessiveness and fickleness. Chapter Four explores time, memory, emotion and death in Macbeth, followed by a study of Henry V, The Tempest and The Winter’s Tale in Chapter Five.
There are two points underlying the argument of the whole thesis. The first point is that, whereas the brain-centred understanding of memory was predominant in early modern England as in other European countries, there was also a heart-centred tradition. Although the brain and reason still occupied pivotal positions in early modern England, the heart and emotion were given substantial attention by Shakespeare among others. As regards the relationship between the heart and the emotions, there were also two divergent attitudes to emotion: praise of emotion and denigration of emotion. As the connotations and history of the term “emotion” are complex, this study distinguishes between it and its synonyms such as passion, affection, feeling and the Chinese concept of qing. Other Chinese philosophies such as Daoism and theories including Yin-Yang theory and “Three Immortality” are also explored to shed light on the foci of this study.
Secondly, this thesis argues that there are two categories of memory, namely, locative memory and fluid memory, and Shakespeare was influenced by both. It also contends that the eradication and displacement of memory provoked anxiety about memory, just as the displacement and annihilation of corpses, mainly caused by plagues and the Reformation as well as other factors, lead to heightened anxiety about death in early modern English culture.the Chinese Scholarship Council (CSC)the Overseas Research Students Awards Scheme (ORSAS
Managerial Risk Tolerance and Corporate Credit Ratings
This study examines whether and how managerial risk tolerance influences corporate credit ratings. Using the possession of a private pilot license to capture CEO risk tolerance, we find that firms led by pilot CEOs have worse credit ratings after controlling for firm fundamentals, CEO risk-taking incentives, and other CEO characteristics. Path analyses show that risk-tolerant CEOs lead to worse credit ratings by reducing the level of future firm value, increasing the volatility of future firm value, and changing rating agencies’ assessment of management. Also, the negative association between CEO risk tolerance and credit ratings is more pronounced when management play a more important role in a firm. Overall, our study sheds light on the dark side of managerial risk tolerance by documenting its adverse impact on corporate credit ratings
Effects on Summer Monsoon and Rainfall Change Over China Due to Eurasian Snow Cover and Ocean Thermal Conditions
Spectral correction method based on improved flat-top convoluted window for parameter estimation of power harmonic
Točna procjena harmonijskog parametra je važan zadatak u obradi signala elektroenergetskog sustava. Predlaže se nova vrsta flat-top prozora koja se generira vlastitim konvolucijama brzo padajućeg flat-top prozora (FDMS-FT) u domenu vremena. Proučavaju se značajke bočnog i glavnog režnja novog prozora. Nadalje, kako bi se poboljšala glatkoća glavnog režnja novog prozora, optimiziraju se koeficijenti matičnog prozora. Predstavlja se izmjenjivi algoritam ispravke razlike faze duljine prozora baziran na novom prozoru kako bi se procijenio strujni harmonični parametar. Kako bi se provjerila učinkovitost i točnost prikazane metode, provedeno je nekoliko računalnih simulacija i praktičnih eksperimenata s višefrekvencijskim strujnim signalima. Rezultati pokazuju da predložena metoda može učinkovito smanjiti opseg računanja i daje visok parametar točnosti procjene harmonijske snage.Accurate estimation of harmonic parameter is an important task in signal processing of power system. A new class of flat-top windows is proposed, which is generated by self-convolutions of the fast-decaying minimum-sidelobe flat-top (FDMS-FT) window in the time-domain. The mainlobe and sidelobe features of the new window are studied. In addition, to improve the flatness of mainlobe of the new window, the coefficients of its parent window are optimized. A window-length changeable discrete phase difference correction algorithm based on the new window is presented to estimate power harmonic parameter. In order to inspect the efficiency and accuracy of the presented method, several computer simulations and practical experiments were conducted with power multi-frequency signals. Results show that the proposed method can reduce the computation load efficiently and gives a high parameter estimation accuracy of power harmonic
Potential roles of the gut microbiota in the manifestations of drug use disorders
Drug use disorders (DUDs) not only cause serious harm to users but also cause huge economic, security, and public health burdens to families and society. Recently, several studies have shown that gut microbiota (GM) can affect the central nervous system and brain functions. In this review, we focus on the potential role of the GM in the different stages of DUDs. First, the GM may induce individuals to seek novel substances. Second, the gut microbiota is involved in the decomposition and absorption of drugs. Symptoms of individuals who suffer from DUDs are also related to intestinal microorganisms. Third, the effects of the GM and its metabolites on drug relapse are mainly reflected in the reward effect and drug memory. In conclusion, recent studies have preliminarily explored the relationship between GM and DUDs. This review deepens our understanding of the mechanisms of DUDs and provides important information for the future development of clinical treatment for DUDs
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