Plant Virus Emergence

This compilation of articles elaborates on plant virus diseases that are among the most recent epidemiological concerns. The chapters explore several paradigms in plant virus epidemiology, outbreaks, epidemics, and pandemics paralleling zoonotic viruses and that can be consequential to global food security. There is evidence that the local, regional, national, and global trade of agricultural products has aided the global dispersal of plant virus diseases. Expanding farmlands into pristine natural areas has created opportunities for viruses in native landscapes to invade crops, while the movement of food and food products disseminates viruses, creating epidemics or pandemics. Moreover, plant virus outbreaks not only directly impact food supply, but also incidentally affect human health

Biology, ecology and management of "Monochamus galloprovincialis" (Olivier): vector of the pine wood nematode

La reciente introducción del “nematodo del pino” en Europa, obliga al desarrollo y aplicación urgente de medidas para la contención de la enfermedad. La actividad humana ha resultado ser el principal mecanismo de dispersión de la enfermedad a larga distancia, pero el conocimiento de la dispersión a escala local es de similar importancia para la toma decisiones sobre las medidas a aplicar. El conocimiento de las dinámicas poblacionales del vector por tanto, aquí juega un papel clave. Conocer cuál es su preferencia de hospedantes, cómo y cuánto se va a dispersar y a qué distancia sería capaz de llegar, aun cuando se encuentre sin alimento, junto con un buen dispositivo de captura, posibilitarán la detección temprana de la enfermedad o incluso el desarrollo de técnicas de control biotécnico como la captura masiva.Departamento de Producción Vegetal y Recursos Forestale

Biology, ecology and management of "Monochamus galloprovincialis" (Olivier): vector of the pine wood nematode

La reciente introducción del “nematodo del pino” en Europa, obliga al desarrollo y aplicación urgente de medidas para la contención de la enfermedad. La actividad humana ha resultado ser el principal mecanismo de dispersión de la enfermedad a larga distancia, pero el conocimiento de la dispersión a escala local es de similar importancia para la toma decisiones sobre las medidas a aplicar. El conocimiento de las dinámicas poblacionales del vector por tanto, aquí juega un papel clave. Conocer cuál es su preferencia de hospedantes, cómo y cuánto se va a dispersar y a qué distancia sería capaz de llegar, aun cuando se encuentre sin alimento, junto con un buen dispositivo de captura, posibilitarán la detección temprana de la enfermedad o incluso el desarrollo de técnicas de control biotécnico como la captura masiva.Departamento de Producción Vegetal y Recursos Forestale

Mathematical and Numerical Aspects of Quantum Chemistry Problems

This workshop was aimed at strengthtening the interactions between well established experts in quantum chemistry, mathematical analysis, numerical analysis and computational metodology. Most of the mathematicians present in the worskhop have already contributed to the theoretical and numerical study of models in quantum physics and chemistry. Some others, familiar with contiguous fiels, were new to chemistry. Several distinguished researchers in theoretical chemistry participated in the workshop, and presented the mathematical and computational challenges of the field

New Developments in Covariance Modeling and Coregionalization for the Study and Simulation of Natural Phenomena

RÉSUMÉ La géostatistique s’intéresse à la modélisation des phénomènes naturels par des champs aléatoires univariables ou multivariables. La plupart des applications utilisent un modèle stationnaire pour représenter le phénomène étudié. Il est maintenant reconnu que ce modèle n’est pas assez flexible pour représenter adéquatement un phénomène naturel montrant des comportements qui varient considérablement dans l’espace (un exemple simple de cette hétérogénéité est le problème de l’estimation de l’épaisseur du mort-terrain en présence d’affleurements). Pour le cas univariable, quelques modèles non-stationnaires ont été développés récemment. Toutefois, ces modèles n’ont pas un support compact, ce qui limite leur domaine d’application. Il y a un réel besoin d’enrichir la classe des modèles non-stationnaires univariable, le premier objectif poursuivi par cette thèse.----------ABSTRACT Geostatistics focus on modeling natural phenomena by univariate or multivariate spatial random fields. Most applications rely on the choice of a stationary model to represent the studied phenomenon. It is now acknowledged that this model is not flexible enough to adequately represent a natural phenomenon showing behaviors that vary substantially in space (a simple example of such heterogeneity is the problem of estimating overburden thickness in the presence of outcrops). For the univariate case, a few non-stationary models were developed recently. However, these models do not have compact support, which limits in practice their range of application. There is a definite need to enlarge the class of univariate non-stationary models, a first goal pursued by this thesis

Handbook of Mathematical Geosciences

This Open Access handbook published at the IAMG's 50th anniversary, presents a compilation of invited path-breaking research contributions by award-winning geoscientists who have been instrumental in shaping the IAMG. It contains 45 chapters that are categorized broadly into five parts (i) theory, (ii) general applications, (iii) exploration and resource estimation, (iv) reviews, and (v) reminiscences covering related topics like mathematical geosciences, mathematical morphology, geostatistics, fractals and multifractals, spatial statistics, multipoint geostatistics, compositional data analysis, informatics, geocomputation, numerical methods, and chaos theory in the geosciences

Real-Time Observations of Quasicrystal Formation

Since the discovery of quasicrystals, there have been continued efforts to explain their growth mechanisms given that their unique structures violate the rules of conventional crystallography. Despite decades of research on the topic, the growth mechanisms of quasicrystals remain one of the fundamental puzzles in the field of crystal growth. To elucidate the growth of quasicrystals, many theories have been proposed. However, there have been very few experimental investigations with which to test the various theories, and quasicrystal growth often accompanies complicated interactions and unexpected growth pathways beyond the scope of these theories. Therefore, to corroborate these theories, it is essential to utilize the benefits of advanced in situ characterization techniques, such as X-ray tomography (XRT) and dynamic transmission electron microscopy (DTEM). The results obtained through these advanced techniques provide direct evidence to support the theories, with high spatial and temporal resolutions. Especially, such in situ approaches allow extracting the information regarding the growth kinetics, growth shapes, and growth interactions which cannot be retrieved from ex situ characterization techniques. In the first and primary part of this thesis, the growth of a single quasicrystal will be discussed. We demonstrate how growth and dissolution pathways of a decagonal quasicrystal are different from each other with respect to the underlying mechanism (interfacial attachment in the former case and bulk transport in the latter). In addition, we compare the growth kinetics of a decagonal quasicrystal with its crystalline approximant, which shares a similar structural motif. Furthermore, we investigate the kinetic and equilibrium shapes of icosahedral quasicrystals. These observations are only possible when we incorporate 4D (i.e., 3D space + time) approaches. The second part of this thesis concerns the growth interactions between multiple quasicrystals. We examine the interfacial phenomena when quasicrystals impinge on each other using 4D XRT and describe the preconditions required for forming a single quasicrystal from multiple quasicrystalline nuclei or ‘seeds’ with the aid of molecular dynamics (MD) simulations. From the XRT results, we can directly observe the formation of a single quasicrystal based on the gradual disappearance of grain boundary grooves. In typical solidification experiments, it is often unavoidable to produce polycrystalline materials, which often deteriorates materials’ properties. Therefore, our joint experiment-computational discovery paves the way toward fabrication of single, large-scale quasicrystals to solve engineering problems. The last part of this thesis covers the solid-state phase transformation from approximant to quasicrystalline phases induced by a short-pulsed laser irradiation. To the best of our knowledge, the real-time investigation of quasicrystal growth far-from-equilibrium has not been reported in a time-resolved manner. Additionally, the solid-state dendritic growth is extremely rare in Nature and several preconditions have to be satisfied for this growth form to manifest. Interestingly, this study demonstrates how quasicrystals grow dendritically showing a huge deviation from their well-known polyhedral growth shapes and what contributes to this unique precipitation pathway. Through ab initio MD simulations, we identify common structural motifs that facilitate the phase transformation between the approximant and quasicrystalline phases. Overall, the findings in this dissertation work are at the forefront of solidification science and have expanded our knowledge on the growth mechanisms of quasicrystals and their approximants using advanced characterization techniques and corresponding simulations.PHDMaterials Science and EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/162855/1/insungh_1.pd