104 research outputs found
Lying and walking surfaces for cattle, pigs and poultry and their impact on health, behaviour and performance
No full textAppropriate housing that promotes excellent health and high welfare for different livestock species is an essential aspect of sustainable animal production. The appropriate design of livestock buildings is a fast changing and ever improving professional endeavour. This book is set out to review the 'current best practice management' in relation to all key design elements of livestock buildings. It is important to manage these buildings correctly to generate environmental conditions that will enhance the health and welfare of livestock, the health of farm workers and people living near farming operations.
'Livestock housing' is written for all those who are involved in managing the health and welfare conditions of housed livestock on commercial farms, including farm workers, animal scientists, veterinarians, agricultural engineers and of course students. Contributions have been solicited from highly respected specialists from around the world. All key areas of housing management are reviewed, including feeding, watering, ventilation and waste management systems. Furthermore, issues such as the control of emissions, role of bedding, maintenance of hygiene, the management of thermal and aerial environment as well as the use of modern technological tools in the service of livestock management are discussed. This book provides a unique forum for leading international experts to convey up-to-date information to professionals involved in modern animal production
Seiberg-Witten curves of -type Little Strings
No full textLittle Strings are a type of non-gravitational quantum theories that contain extended degrees of freedom, but behave like ordinary Quantum Field Theories at low energies. A particular class of such theories in six dimensions is engineered as the world-volume theory of an M5-brane on a circle that probes a transverse orbifold geometry. Its low energy limit is a supersymmetric gauge theory that is described by a quiver in the shape of the Dynkin diagram of the affine extension of an ADE-group. While the so-called -type Little String Theories (LSTs) are very well studied, much less is known about the -type, where for example the Seiberg-Witten curve (SWC) is only known in the case of the theory. In this work, we provide a general construction of this curve for arbitrary that respects all symmetries and dualities of the LST and is compatible with lower-dimensional results in the literature. For our construction reproduces the same curve as previously obtained by other methods. The form in which we cast the SWC for generic allows to study the behaviour of the LST under modular transformations and provides insights into a dual formulation as a circular quiver gauge theory with nodes of and .30 page
Seiberg-Witten curves of -type Little Strings
No full textInternational audienceLittle Strings are a type of non-gravitational quantum theories that contain extended degrees of freedom, but behave like ordinary Quantum Field Theories at low energies. A particular class of such theories in six dimensions is engineered as the world-volume theory of an M5-brane on a circle that probes a transverse orbifold geometry. Its low energy limit is a supersymmetric gauge theory that is described by a quiver in the shape of the Dynkin diagram of the affine extension of an ADE-group. While the so-called -type Little String Theories (LSTs) are very well studied, much less is known about the -type, where for example the Seiberg-Witten curve (SWC) is only known in the case of the theory. In this work, we provide a general construction of this curve for arbitrary that respects all symmetries and dualities of the LST and is compatible with lower-dimensional results in the literature. For our construction reproduces the same curve as previously obtained by other methods. The form in which we cast the SWC for generic allows to study the behaviour of the LST under modular transformations and provides insights into a dual formulation as a circular quiver gauge theory with nodes of and
The development of a business model in a Brazilian biotechnology startup
No full textAs empresas startup na área de biotecnologia podem adotar um portfólio de modelo de negócios diversificado com o intuito de maximizar a captação de valor do know how e das atividades associadas à pesquisa e desenvolvimento. O equilíbrio entre esses modelos de negócios é determinante para a geração de receita para subsidiar o longo prazo intrínseco ao desenvolvimento do negócio derivado de pesquisa e desenvolvimento em biotecnologia. Nesse cenário, é relevante a análise e seleção do método apropriado de construção de modelos de negócios para empresas startup no setor de biotecnologia. O presente estudo tem como objetivo desenvolver o modelo de negócios de uma startup de biotecnologia de diagnóstico molecular no mercado brasileiro. O método de pesquisa adotado foi a pesquisa-ação que derivou na seleção do método de construção de modelo de negócios descrito por Pedroso, 2018. A autora demonstra que a aplicação desse método em uma startup brasileira de biotecnologia gerou 4 ciclos interativos de planejamento, ação, avaliação e diagnóstico. Ainda, a autora aponta sugestões para a aplicação desse método em empresas brasileiras startup de biotecnologia.Startups in the biotechnology area may adopt a diversified business model portfolio that seek to maximize the value of know-how and activities associated with research and development. The balance between these business models is decisive for the generation of revenue to subsidize the long term intrinsic to the development of the business derived from research and development in biotechnology. In this scenario, it is relevant to analyze and select the appropriate method to construct business models for startup companies in the biotechnology sector. The present study aims to develop the business model of a biotechnology startup on the molecular diagnostic sector in the Brazilian market. The research method adopted was the action research that resulted on the selection of the method of business model construction described by Pedroso, 2018. The author shows that the application of said method in a Brazilian biotech startup generated 4 interactive cycles of planning, action, evaluation and diagnostic. In addition, the author gives some suggestions for applying this method on Brazilian startup
Aspects non-perturbatifs des petites théories des cordes
No full textString theory is a well-established framework for describing quantum gravity, and it also provides insights into supersymmetric gauge theories. A common approach involves studying the low-energy limit of the worldvolume theory of a stack of D-branes, resulting in, for instance, four-dimensional gauge theories. Alternatively, string theory predicts the existence of non-local non-gravitational theories in six-dimensions which are known as little string theories. These theories provide a rich framework for investigating string theory and gauge theories as non-local extensions of supersymmetric gauge theories. This thesis focuses on the non-perturbative aspects of a specific class of little string theories, known as A-type little string theories. We demonstrate that their BPS partition function, which encodes the non-perturbative information of the theory, can be decomposed into modular building blocks. This decomposition facilitates the study of particular limits of the partition function, revealing recursive structures. Furthermore, we identify non-trivial symmetries of the partition function that do not respect the non-perturbative expansion. These symmetries are derived by examining the extended Kähler moduli space of the theory and are validated using the vertex operator algebraic reformulation of the partition function. The partition function can be further extended to include codimension-2 surface defects. We construct the defect partition function and show that it preserves the same symmetries as the defect-free case. Additionally, we investigate the regularity of the defect partition function and demonstrate its factorization in the Nekrasov-Shatashvili limit. Finally, we study the Seiberg-Witten curves associated with a different class of little string theories, the D-type little string theories. By leveraging symmetry and modularity arguments, we constrain the possible forms of these curves and explore their properties and dualities with other theories.La théorie des cordes est un cadre bien établi pour décrire la gravité quantique, et elle fournit également des informations sur les théories de jauge supersymétriques. Une approche courante consiste à étudier la limite basse énergie de la théorie contenu dans un empilement de D-branes, ce qui donne lieu, par exemple, à des théories de jauge en quatre dimensions. Alternativement, la théorie des cordes prédit l'existence de théories non locales non gravitationnelles en six dimensions, connues sous le nom de petites théories des cordes. Ces théories offrent un cadre riche pour explorer la théorie des cordes et les théories de jauge comme des extensions non locales des théories de jauge supersymétriques. Cette thèse se concentre sur les aspects non perturbatifs d'une classe spécifique de théories des petites cordes, connues sous le nom de théories des petites cordes de type A. Nous démontrons que leur fonction de partition BPS, qui encode les informations non perturbatives de la théorie, peut être décomposée en blocs modulaires. Cette décomposition facilite l'étude de limites particulières de la fonction de partition, révélant des structures récursives. D'autre part, nous identifions des symétries non triviales de la fonction de partition qui ne respectent pas le développement non perturbatif. Ces symétries sont dérivées en examinant l'espace des modules de Kähler étendu de la théorie et sont validées à l'aide d'une reformulation algébrique en terme d'opérateurs vertex de la fonction de partition. La fonction de partition peut être étendue pour inclure des défauts de surface de codimension 2. Nous construisons la fonction de partition avec défauts et montrons qu'elle préserve les mêmes symétries que dans le cas sans défauts. D'autre part, nous examinons la régularité de la fonction de partition avec défauts et démontrons sa factorisation dans la limite de Nekrasov-Shatashvili. Enfin, nous étudions les courbes de Seiberg-Witten associées à une autre classe de petites théories des cordes, les petites théories des cordes de type D. En exploitant des arguments de symétrie et de modularité, nous contraignons les formes possibles de ces courbes et explorons leurs propriétés ainsi que leurs dualités avec d'autres théories
Aspects non-perturbatifs des petites théories des cordes
No full textString theory is a well-established framework for describing quantum gravity, and it also provides insights into supersymmetric gauge theories. A common approach involves studying the low-energy limit of the worldvolume theory of a stack of D-branes, resulting in, for instance, four-dimensional gauge theories. Alternatively, string theory predicts the existence of non-local non-gravitational theories in six-dimensions which are known as little string theories. These theories provide a rich framework for investigating string theory and gauge theories as non-local extensions of supersymmetric gauge theories. This thesis focuses on the non-perturbative aspects of a specific class of little string theories, known as A-type little string theories. We demonstrate that their BPS partition function, which encodes the non-perturbative information of the theory, can be decomposed into modular building blocks. This decomposition facilitates the study of particular limits of the partition function, revealing recursive structures. Furthermore, we identify non-trivial symmetries of the partition function that do not respect the non-perturbative expansion. These symmetries are derived by examining the extended Kähler moduli space of the theory and are validated using the vertex operator algebraic reformulation of the partition function. The partition function can be further extended to include codimension-2 surface defects. We construct the defect partition function and show that it preserves the same symmetries as the defect-free case. Additionally, we investigate the regularity of the defect partition function and demonstrate its factorization in the Nekrasov-Shatashvili limit. Finally, we study the Seiberg-Witten curves associated with a different class of little string theories, the D-type little string theories. By leveraging symmetry and modularity arguments, we constrain the possible forms of these curves and explore their properties and dualities with other theories.La théorie des cordes est un cadre bien établi pour décrire la gravité quantique, et elle fournit également des informations sur les théories de jauge supersymétriques. Une approche courante consiste à étudier la limite basse énergie de la théorie contenu dans un empilement de D-branes, ce qui donne lieu, par exemple, à des théories de jauge en quatre dimensions. Alternativement, la théorie des cordes prédit l'existence de théories non locales non gravitationnelles en six dimensions, connues sous le nom de petites théories des cordes. Ces théories offrent un cadre riche pour explorer la théorie des cordes et les théories de jauge comme des extensions non locales des théories de jauge supersymétriques. Cette thèse se concentre sur les aspects non perturbatifs d'une classe spécifique de théories des petites cordes, connues sous le nom de théories des petites cordes de type A. Nous démontrons que leur fonction de partition BPS, qui encode les informations non perturbatives de la théorie, peut être décomposée en blocs modulaires. Cette décomposition facilite l'étude de limites particulières de la fonction de partition, révélant des structures récursives. D'autre part, nous identifions des symétries non triviales de la fonction de partition qui ne respectent pas le développement non perturbatif. Ces symétries sont dérivées en examinant l'espace des modules de Kähler étendu de la théorie et sont validées à l'aide d'une reformulation algébrique en terme d'opérateurs vertex de la fonction de partition. La fonction de partition peut être étendue pour inclure des défauts de surface de codimension 2. Nous construisons la fonction de partition avec défauts et montrons qu'elle préserve les mêmes symétries que dans le cas sans défauts. D'autre part, nous examinons la régularité de la fonction de partition avec défauts et démontrons sa factorisation dans la limite de Nekrasov-Shatashvili. Enfin, nous étudions les courbes de Seiberg-Witten associées à une autre classe de petites théories des cordes, les petites théories des cordes de type D. En exploitant des arguments de symétrie et de modularité, nous contraignons les formes possibles de ces courbes et explorons leurs propriétés ainsi que leurs dualités avec d'autres théories
Le modèle d'Anderson discret : densité d’états intégrée, valeur propre principale et fonction Landscape.
No full textIn this PhD thesis we accomplish two objectives:- We show there is countable dense set at which the integrated density of sates of the Anderson-Bernoulli model on can be explicitly computed, provided the disorder parameter is large enough.- We give a partial proof a a conjecture, first stated in a 2012 article by Filoche and Mayboroda, concerning the product of principal eigenvalue and sup-norm of the landscape function of the Anderson model operator restricted to a large box of . For the one dimensional case, we give a full proof of such conjecture.Dans cette thèse de doctorat, nous atteignons deux objectifs :- Nous montrons qu'il existe un ensemble dense dénombrable auquel la densité d'états intégrée du modèle d'Anderson-Bernoulli sur peut être explicitement calculée, à condition que le paramètre de désordre soit suffisamment grand.- Nous donnons une preuve partielle d'une conjecture, énoncée pour la première fois dans un article de 2012 par Filoche et Mayboroda, concernant le produit de la valeur propre principale et la sup-norme de la fonction landscape de l'opérateur du modèle d'Anderson restreint à une grande boîte de . Pour le cas unidimensionnel, nous donnons une preuve complète de cette conjecture
Can one hear the shape of an electrode? II. Theoretical study of the Laplacian transfer
No full textThe flux across resistive irregular interfaces driven by a
force deriving from a Laplacian potential is computed on a rigorous
basis. The theory permits one to relate the size of the active zone
Aact. to the derivative of the spectroscopic impedance
with respect to the surface resistivity r
through: . It is shown that
the macroscopic transfer properties through a system of arbitrary
shape are determined by the characteristics of a first-passage
interface-interface random walk operator. More precisely, it is the
distribution of the harmonic measure (or normalized primary current)
on the eigenmodes of this linear operator that controls the
transfer. In addition, it is also shown that, whatever the dimension,
the impedance of a weakly polarizable electrode for any irregular
geometry scales under a homothety transformation as , L
being the size of the system and d its topological dimension. In
this new formalism, the question addressed in the title is transformed
in a open mathematical question: "Knowing the distribution of the
harmonic measure on the eigenmodes of the self-transport operator, can
one retrieve the shape of the interface?
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