992 resultados para Box-Cox transformation
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Over 7 years, this project collected data about the pasture, tree and soil surface dynamics of two major Aristida/Bothriochloa pasture types within the eucalypt woodlands of central Queensland. Six different grazing management scenarios were compared ecologically and economically, along with the effects of spring burns and tree killing. Heavy stocking (3-4 ha per adult equivalent) produced the greatest short-term financial return from healthy pastures but was not a sustainable practice and long-term cash returns were no better than those from moderate stocking. The environmental benefits of moderate grazing over heavy grazing were very clear. Light stocking produced better environmental outcomes compared to moderate stocking but was clearly inferior with respect to economic returns. Killing silver-leaved ironbark trees near Rubyvale produced no measurable improvement in pasture growth or quality for at least 6 years whereas at Injune the same treatment of poplar box trees resulted in an immediate and large enhancement in pasture production and carrying capacity. The gritty red duplex soil at Rubyvale was much more erodible than the grey solodic at Injune although the latter becomes very erodible if the stable surface soil is breached. Good seasonal rainfall produced faster changes in pasture composition than extremes of grazing management. The perennial grasses were easier to recruit than to eliminate by grazing management changes.
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Epilysin (MMP-28) is the most recently identified member of the matrix metalloproteinase (MMP) family of extracellular proteases. Together these enzymes are capable of degrading almost all components of the extracellular matrix (ECM) and are thus involved in important biological processes such as development, wound healing and immune functions, but also in pathological processes such as tumor invasion, metastasis and arthritis. MMPs do not act solely by degrading the ECM. They also regulate cell behavior by releasing growth factors and biologically active peptides from the ECM, by modulating cell surface receptors and adhesion molecules and by regulating the activity of many important mediators in inflammatory pathways. The aim of this study was to define the unique role of epilysin within the MMP-family, to elucidate how and when it is expressed and how its catalytic activity is regulated. To gain information on its essential functions and substrates, the specific aim was to characterize how epilysin affects the phenotype of epithelial cells, where it is biologically expressed. During the course of the study we found that the epilysin promoter contains a well conserved GT-box that is essential for the basic expression of this gene. Transcription factors Sp1 and Sp3 bind this sequence and could hence regulate both the basic and cell type and differentiation stage specific expression of epilysin. We cloned mouse epilysin cDNA and found that epilysin is well conserved between human and mouse genomes and that epilysin is glycosylated and activated by furin. Similarly to in human tissues, epilysin is normally expressed in a number of mouse tissues. The expression pattern differs from most other MMPs, which are expressed only in response to injury or inflammation and in pathological processes like cancer. These findings implicate that epilysin could be involved in tissue homeostasis, perhaps fine-tuning the phenotype of epithelial cells according to signals from the ECM. In view of these results, it was unexpected to find that epilysin can induce a stable epithelial to mesenchymal transition (EMT) when overexpressed in epithelial lung carcinoma cells. Transforming growth factor b (TGF-b) was recognized as a crucial mediator of this process, which was characterized by the loss of E-cadherin mediated cell-cell adhesion, elevated expression of gelatinase B and MT1-MMP and increased cell migration and invasion into collagen I gels. We also observed that epilysin is bound to the surface of epithelial cells and that this interaction is lost upon cell transformation and is susceptible to degradation by membrane type-1-MMP (MT1-MMP). The wide expression of epilysin under physiological conditions implicates that its effects on epithelial cell phenotype in vivo are not as dramatic as seen in our in vitro cell system. Nevertheless, current results indicate a possible interaction between epilysin and TGF-b also under physiological circumstances, where epilysin activity may not induce EMT but, instead, trigger less permanent changes in TGF-b signaling and cell motility. Epilysin may thus play an important role in TGF-b regulated events such as wound healing and inflammation, processes where involvement of epilysin has been indicated.
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There exists a remarkably close relationship between the operator algebra of the Dirac equation and the corresponding operators of the spinorial relativistic rotator (an indecomposable object lying on a mass-spin Regge trajectory). The analog of the Foldy-Wouthuysen transformation (more generally, the transformation between quasi-Newtonian and Minkowski coordinates) is constructed and explicit results are discussed for the spin and position operators. Zitterbewegung is shown to exist for a system having only positive energies.
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Extending the work of earlier papers on the relativistic-front description of paraxial optics and the formulation of Fourier optics for vector waves consistent with the Maxwell equations, we generalize the Jones calculus of axial plane waves to describe the action of the most general linear optical system on paraxial Maxwell fields. Several examples are worked out, and in each case it is shown that the formalism leads to physically correct results. The importance of retaining the small components of the field vectors along the axis of the system for a consistent description is emphasized.
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The transformation of vaterite to calcite was investigated systematically. The transition temperature and the energetics of the transformation were determined from differential thermal curves. The variations of lattice constants and crystallite size, accompanying the transformation were studied by X-ray diffractometry. The kinetics of transformation were investigated in the temperature range 460–490°C. The kinetic data were analysed with the help of three separate solid-state models.
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The session examines the role of the metaphysical and physical in art and animation and how this relates to natural spaces. Soviet Russian film director and theorist Sergei Eisenstein saw animation as possessing an ability called “plasmaticity”, the capacity for a being to assume any conceivable form dynamically. He saw each being as “primordial protoplasm, not yet possessing a ‘stable’ form, but capable of assuming any form” (Eisenstein 1989, 21). He was enamoured by the capacity of animation to transform and be liberated, of being able to escape from a fixed and static identity—to embody a "rejection of the once-‐and-‐forever allotted form" in which we are held (Eisenstein 1989, 21). Czech Surrealist animator Jan Švankmajer uses a metaphysical approach based on a belief in animism to art and animation. He believes that objects possess a conscious life or spirit, he says ‘Objects conceal within themselves the events they’ve witnessed. I don’t actually animate objects. I coerce their inner life out of them.’ (Švankmajer in Imre 2009, 214) In this animistic world there are no boundaries or rules, no physical or conceptual restrictions; anything is possible, with inanimate objects and places able to become animate and transact in a conscious relationship with humans and each other. This session invites artists, animators and theorists to discuss their conceptions and approaches to using visuals to promote and provoke transformation.
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Collection contains materials pertaining to the life and work of Stone.
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In an earlier paper (Part I) we described the construction of Hermite code for multiple grey-level pictures using the concepts of vector spaces over Galois Fields. In this paper a new algebra is worked out for Hermite codes to devise algorithms for various transformations such as translation, reflection, rotation, expansion and replication of the original picture. Also other operations such as concatenation, complementation, superposition, Jordan-sum and selective segmentation are considered. It is shown that the Hermite code of a picture is very powerful and serves as a mathematical signature of the picture. The Hermite code will have extensive applications in picture processing, pattern recognition and artificial intelligence.
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This paper describes the application of vector spaces over Galois fields, for obtaining a formal description of a picture in the form of a very compact, non-redundant, unique syntactic code. Two different methods of encoding are described. Both these methods consist in identifying the given picture as a matrix (called picture matrix) over a finite field. In the first method, the eigenvalues and eigenvectors of this matrix are obtained. The eigenvector expansion theorem is then used to reconstruct the original matrix. If several of the eigenvalues happen to be zero this scheme results in a considerable compression. In the second method, the picture matrix is reduced to a primitive diagonal form (Hermite canonical form) by elementary row and column transformations. These sequences of elementary transformations constitute a unique and unambiguous syntactic code-called Hermite code—for reconstructing the picture from the primitive diagonal matrix. A good compression of the picture results, if the rank of the matrix is considerably lower than its order. An important aspect of this code is that it preserves the neighbourhood relations in the picture and the primitive remains invariant under translation, rotation, reflection, enlargement and replication. It is also possible to derive the codes for these transformed pictures from the Hermite code of the original picture by simple algebraic manipulation. This code will find extensive applications in picture compression, storage, retrieval, transmission and in designing pattern recognition and artificial intelligence systems.
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Purpose of the paper: The paper advocates a Darwinian explanation of the process of firm transformation. Existing, but generally opposing views related to the selection-adaptation debates are united to consider the dialogic nature of both approaches. It is argued that a Darwinian approach, as opposed to a neo-Darwinian or Lamarckian approach provides the means to scale the sides of a debate that has for too long divided scholars interested in firm and industry transformation. Approach: The paper addresses three specific issues to develop its Darwinian argument. Firstly, the various work of Geoff Hodgson that have for many years advanced Darwin's evolutionary ideas are used to argue the nature and application of Darwinism in the socio-economic domain. Secondly, the nature of what constitutes the elements of firm-environment interaction is considered to establish basic areas of focus through which the process of firm transformation is more understandable. Lastly, the construct absorptive capacity is likened to a mechanism of transmission through which the learning processes associated with the acquisition of favoured variations can be reconciled with the generic evolutionary processes of variation, selection, and retention. Findings: To understand the process of firm learning, the role of habits and routines must be outlined in specific detail. They cannot be assumed to perform interacting and replicating roles simultaneously. To do so, undermines the fundamental qualities of an evolutionary theory. What is the original/value of paper: The preliminary framework advanced takes us beyond the Darwinian - Lamarckian debate and provides elements of focus from which a greater understanding of the process of firm/industry transformation is possible.
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Oversized materials is the digitized contents of one box (OS1) that consists of correspondence and an address from Box 2, Folders 12, 13 and 17.
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Oversized materials is the digitized contents of one box (OS1) that consists of correspondence and an address from Box 2, Folders 12, 13 and 17.
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Oversized materials is the digitized contents of one box (OS1) that consists of correspondence and an address from Box 2, Folders 12, 13 and 17.
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Oversized materials is the digitized contents of one box (OS1) that consists of correspondence and an address from Box 2, Folders 12, 13 and 17.