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This chapter begins with a discussion of the problem of disconnection (and the process of re-connection). It introduces three key distinctions: one between ‘descriptive’ and ‘normative’ disconnection, a second between ‘productive’ and ‘unproductive’ disconnection, and a third between ‘intelligent’ and ‘unintelligent’ purposive re-connection. It then reviews the way in which the English courts have recently responded to disconnection — with particular reference to the rapidly developing technologies of cell nuclear replacement (CNR), pre-implantation genetic diagnosis (PGD), and pre-implantation tissue-typing (PTT) — by seeking to reconnect the regulatory framework (namely, the Human Fertilisation and Embryology Act 1990). It is argued that where interpreters face a case that is not straightforwardly one of unproductive descriptive disconnection, there is a danger that reconnection effected through purposive interpretation might not only fall foul of the principle of congruence but also hinder the need for a reconsideration of the law.

This chapter argues for reconsideration of Ishmael Reed’s position to Black Arts movement. It shows that in his novel Japanese by Spring, Reed nurtures a key theme of the movement (reconnection to Africa) even at times when the movement itself could not connect to Africa and when such a goal was perceived as outdated. The chapter is grounded in contemporary research on BAM and ultimately argues for a closer connection between Reed and BAM. In doing so, it updates the common misconception regarding Reed’s relationship with BAM and claims that his works should be included in the recent research on the Black Arts movement.

Fragmentation is the process by which the primary partons produced in a hard subprocess convert into the sprays of hadrons seen by experiments. This chapter describes experimental observations about the fragmentation process, such as multiplicities and momentum spectra of identified particles, and how soft gluon interference and colour coherence affects the particle flow in interjet regions. Special emphasis is given to two-particle correlations, i.e. quantum number correlations and Bose–Einstein correlations. Finally, colour reconnection in multi-parton environments is discussed.

In addition to the Alfv èn wave, field-freezing and the consequent Lorentz force yield fast and slow magnetoacoustic waves, and magnetohydrodynamic shocks. The integral scalar and tensorial virial theorems are a reliable guide to the effect of large-scale, frozen-in magnetic fields on self-gravitating systems. Magnetostatic equilibria include, as a sub-class, domains with locally force-free fields. Magnetic helicity is a measure of a topological property of a field, which in a dissipative system may be destroyed more slowly than magnetic energy. The MHD energy principle is a valuable tool for the study of the dynamical stability of MHD equilibria. For systems with a zero-order velocity, e.g. rotating systems, one has normally to go straight to the perturbed dynamical and kinematical equations. In some MHD problems, instability can result when Ohmic dissipation leads to field reconnection. In general, one must consider fields with both poloidal and toroidal components.

This chapter looks at the different forms that memory, mourning, and memorialization take in the aftermath of the Cambodian genocide and examines diasporic longing for reconnection and the different facets and layers of transnationality that manifest in the Cambodian American community. With the ancestral homeland connoting both solace and pain, it also reflects on the ambivalence that inhabits the spaces of disconnection and reconnection, and examines the ways in which memory travels across time, space, and generations. In looking at the relationships of diasporas with the homeland, the section focuses not only on the context of exit but also of resettlement in the U.S. as it informs the sense of non-belonging.

This chapter introduces basic concepts related to phylogenetic trees such as rooted and unrooted trees, consensus trees and partition distance, species trees, and gene trees. It discusses general features of tree reconstruction methods, including exhaustive and heuristic tree searches, local optima in the tree space, and tree rearrangement algorithms such as nearest neighbour interchange (NNI), subtree pruning and regrafting (SPR), and tree bisection and reconnection (TBR). The chapter also discusses distance (UPGMA (Unweighted Pair-Group Method using Arithmetic Averages), least squares, and neighbour joining) and parsimony methods of phylogeny reconstruction.

This chapter discusses the implementation of various models of genetic sequence evolution in Bayesian phylogenetic analysis. It discusses the specification of priors for parameters in such models, as well as proposals that change those parameters. The chapter provides an extensive discussion of various tree perturbation algorithms used as Markov chain Monte Carlo (MCMC) proposals (such as nearest neighbour interchange (NNI), subtree pruning and regrafting (SPR), tree bisection and reconnection (TBR), etc.), as well as strategies for generating branch lengths in the new proposed tree. Several strategies for deriving the proposal ratios in sophisticated moves are illustrated with examples. The issue of extremely high posterior probabilities for trees or clades is discussed.

Digital media has spawned entire industries centered on geosurveillance, resulting in complex flows of sensitive data. Practices surrounding the collection, use, and sale of this data are commonly concealed behind lengthy privacy policies riddled with legal jargon and devoid of technical specificity. Simultaneously, new methods of analysis tease out information from even “anonymized” data. As a result, it increasingly seems that the only reliable shelter from geosurveillance is to disconnect, but how difficult is this in practice, is it worth pursuing, and how might we do so? This chapter examines these questions. It first outlines several conceptualizations of privacy and establishes what is at stake every time privacy is eroded. It then overviews the many mechanisms that can produce geospatial data, illustrating the ubiquity of geosurveillance and difficulty of disconnection. Finally, and despite this difficulty, it discusses tactics for resistance, demonstrating that modern privacy requires not just disconnection, but reconnection.

This chapter discusses the consequences of the sun’s magnetic fields, such as the hot corona producing the solar wind, solar flares and coronal mass ejections. The basic physics behind coronal heating and magnetic reconnection is described at an elementary level. The chapter explains how solar disturbances affect the earth.

In the year 1600, the the man about to become physician to Queen Elizabeth I of England published a long treatise summarizing his two decades of experimentation on magnetism. After disposing of such issues as whether garlic causes magnets to “lose their virtue” William Gilbert recounted his observations upon moving a compass over the surface of a permanent magnet that had been specially fashioned in the form of a sphere (Gilbert, 1893, 1958). The similarity between the compass readings on the surface of his magnet and those recorded in mariners’ charts led Gilbert to conclude that his magnet was a terrella, a little earth, and that our big earth is (among other things) a giant magnet. Gilbert’s little earth organized the pattern of compass readings not only on its surface but also in the space surrounding it. From this, he boldly asserted that the big earth’s magnetic influence continues far into empty space, where no mariner of his day could ever go. The profundity of this remark was not lost on Gilbert’s younger contemporary, Johannes Kepler, who found in it an explanation of the earth’s annual motion around the sun. Kepler reasoned more or less as follows (in modern language): Since the earth and the sun are both celestial bodies, they both should rotate, and they both should have magnetic fields surrounding them in space. Their two rotating fields interact somehow, somewhere, in the space between them, communicating the sun’s rotational motion to the earth and pushing the earth around its orbit. In this curious way, Kepler might have been the first to perceive that the sun acts upon terrestrial magnetism. He was not the last. In 1580, Kepler’s teacher, Michael Maestlin, had recorded an observation of a distinct region of oscillating luminosity in the northern sky, an aurora. The aurora had been a topic of scientific interest since Graeco-Roman antiquity [of particular importance was Aristotle’s (384-322 B.C.) discussion of it in his Meteorology], but it had become an object of superstition in the European Middle Ages, and scientific interest in it only began to re-emerge in the second half of the 16th century (Link, 1957).