bluuebunny/crossref_metadata_2025_split huggingface dataset:
European Elections, Euroscepticism, and Support for Anti‐European Union Parties
Authors: van der Brug Wouter 
Published: March 2016

Abstract
The chapter tests the idea that European elections might fuel Euroscepticism by providing a regular forum for those who oppose European unification to spread their message. This chapter first explores the strength of the relationships between citizens’ attitudes towards Europe, their support for anti‐EU parties (both measured through surveys), and the positions on Europe of the party they support (measured by combining survey material and content analyses of party manifestos). These three turn out to be strongly related. However, there is no evidence that these relationships become stronger over time or stronger as a result of the increased politicization around European elections. So, the analyses in this chapter have not provided support for this idea, but they have not rejected it either.
Choose Actionable Problems that Address Civic, Business, and Global Priorities
Authors: Shneiderman Ben 
Published: March 2016

Abstract
Contributing to research by solving contemporary civic problems, often with business partners, has an attractive dual-use or twin-win appeal for many researchers. Dealing with real-world problems and global priorities may improve research products and raise their impact. Having interested collaborators is a great stimulus for producing high quality, since someone cares about the research results and might put them to work promptly to improve products or services. During problem selection, researchers and teams make decisions about what they will work on for months or years. Those who develop a stable internal gyroscope to steer their research are likely to reach their goals.
Test Ideas and Prototypes with Realistic Interventions
Authors: Shneiderman Ben 
Published: March 2016

Abstract
Taking on ambitious decade-long projects that address substantial civic, business, and global priorities requires large teams of diverse researchers. It also requires wisely chosen research strategies that start small with proof of concept studies and then employ scaling up (increased volume) and scaling out (increased diversity) to ensure validity and generalizability of the applied and basic research goals. Successful strategies include progressive investment of effort and resources in (1) agile processes for iterative prototype refinement as theories and practical guidelines are refined (2) big data analysis for pattern detection and predictive models, (3) case study reports to seek causal clarity through qualitative data analysis, and (4) visual analytics for exploration, discovery, and innovation.
Recommendations for Action
Authors: Shneiderman Ben 
Published: March 2016

Abstract
Since this book values theory and practice, it seems reasonable to sum up with a theory of how the research ecosystem functions and practical recommendations for change agents. Inspired by Kurt Lewin’s belief that in order to understand something, one must try and change it, this chapters makes the book’s theory of how the research ecosystem functions explicit. This theory is then used to generate practical recommendations for policy change, which are hoped will feed back into a refined theory.
Change Is Hard, but Possible
Authors: Shneiderman Ben 
Published: March 2016

Abstract
The first step in making substantial change is to understand the status quo and then to offer a clear path forward to an attainable destination. In most established communities, devotion to tradition is strong, so gaining consensus for change is difficult; but dialog is a healthy process for refining ideas and gaining buy-in to make change. Reorienting the research community to these new principles and getting them to integrate new ways of thinking is a continuing challenge.
Long-range Order, Symmetry Breaking, and Order Parameter
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter introduces the fundamental concepts of off-diagonal long-range order, breaking of gauge symmetry, and order parameter, which underlie the concept of Bose–Einstein condensation. The consequences for the momentum distribution and the possibility of separating a classical term in the Bose field operator associated with the condensate, from a non-condensed component, accounting for thermal and quantum fluctuations, are discussed. The macroscopic classical term provides a natural definition of the complex order parameter, characterized by a modulus and a phase.
Weakly Interacting Bose Gas
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter develops the mean-field Bogoliubov theory of the weakly interacting Bose–Einstein condensed gas. Results for the ground state energy, momentum distribution, and excitation spectrum are discussed. Emphasis is given to the behaviour of the sound velocity and its relationship with the s-wave scattering length. Special focus is given to the infrared divergent behaviour of the momentum distribution as well as to its behaviour at high momenta. The concept of healing length is introduced. The quantum and thermal depletion of the condensate fraction are explicitly derived. Beyond-mean effects in the equation of state, accounted for by the Lee–Yang–Huang expansion, are also discussed.
Nonuniform Bose Gases at Zero Temperature
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter develops the theory of weakly interacting nonuniform Bose gases at zero temperature. Interaction effects are accounted for by a single coupling constant fixed by the value of the s-wave scattering length. The nonlinear Gross–Pitaevskii equation is derived in both the stationary and time-dependent cases. The irrotational nature of the flow and the crucial role played by the chemical potential are highlighted. The classical nature of the equation is emphasized and the analogy with the Maxwell equations of classical electrodynamics is pointed out. The stationary solutions of the Gross–Pitaevskii equation, corresponding to quantized vortex lines, vortex rings, and solitons, are discussed. The time-dependent solutions corresponding to small-amplitude oscillations are derived and the corresponding dispersion relation is shown to coincide with the predictions of Bogoliubov theory for uniform media. The Thomas–Fermi limit is also discussed.
Atomic Gases: Collisions and Trapping
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter provides a summary of some relevant interatomic collisional properties at low energy. Low-energy collisions allow for a fundamental understanding of the role of interactions in dilute gases and are determined by the s-wave scattering length. This is the basic interaction parameter that permits us to describe an important variety of many-body properties of dilute Bose–Einstein condensed gases, as well as of superfluid Fermi gases. This interaction parameter also allows us to describe the formation of bound pairs of atoms in the presence of a Feshbach resonance. A special section is devoted to the study of collisional effects in two dimensions. The second part of the chapter illustrates typical schemes for magnetic and optical trapping currently employed to confine neutral atoms.
The Ideal Bose Gas in the Harmonic Trap
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter describes the main properties of the ideal Bose gas confined by a harmonic potential. It calculates the temperature dependence of the condensate density and identify the value of the critical temperature in terms of the oscillator frequency and the number of atoms. This identification provides an important temperature scale for experiments with ultracold atomic gases. The chapter also discusses the behaviour of the expanding cloud after the release of the trap and how the anisotropy of the gas evolves in time, reflecting the initial anisotropy of the momentum distribution. It finally discusses the possibility of getting Bose–Einstein condensation through adiabatic transformations, working with non-harmonic trapping potentials or with mixtures of two atomic species trapped by different harmonic potentials.
Dynamics of a Trapped Condensate
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter provides a general discussion of the dynamic behaviour characterizing a harmonically trapped interacting Bose gas. Explicit results for the frequencies of the collective oscillations were derived by using the hydrodynamic theory of superfluids. Both surface and oscillation of compressional nature are considered and a direct comparison is presented with available experimental results. Sum rules are used to characterize the behaviour of the oscillations. Finite-size as well as beyond-mean-field effects are considered. A special discussion is devoted to the study of large-amplitude oscillations and of the expansion of the gas. The anisotropic expansion predicted by hydrodynamic theory is discussed in a systematic way. An important part of the chapter concerns the study of the dynamic structure factor and its determination in experiments based on two-photon Bragg spectroscopy. Finally, the competition between single-particle and collective modes in the excitation spectrum of a harmonically trapped BEC is discussed.
Superfluidity and Rotation of a Trapped Bose Gas
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter is devoted to discussing some key superfluid properties exhibited by dilute Bose gases confined in external traps. Key issues concern the behaviour of the critical velocity and the applicability of Landau’s criterion for superfluidity, the moment of inertia and its quenching caused by the irrotationality of the superfluid motion, the scissors mode, and the expansion of a rotating superfluid cloud. Rotational effects at high angular velocities, with the appearance of quantized vortices and vortex lattices, are also considered. The chapter also discusses the consequences for vortices on the collective oscillations of the trapped gas, the stability and the precession of vortex lines, and the nature of the superfluid flow in toroidal traps.
Interacting Fermi Gases and the BCS–BEC Crossover
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis is the first of a series of chapters devoted to interacting Fermi gases, with special focus here on the effects of superfluidity. It starts with a brief discussion of the ideal Fermi gas and then focuses on the properties of dilute interacting Fermi gases. Topics include the weakly repulsive Fermi gas; the gas of composite bosons; the BCS limit of a weakly interacting Fermi gas; the strongly interacting, but still dilute, unitary Fermi gas where the scattering length is much larger than the average interatomic distance; the BCS–BEC crossover; and the Bogoliubov–de Gennes approach. A discussion of the main physical quantities predicted by mean-field theory and by quantum Monte Carlo simulations, including, in particular, the equation of state, the momentum distribution, and the condensation of pairs, is also presented.
Fermi Gas in the Harmonic Trap
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter deals with Fermi gases confined in harmonic traps. After offering a reminder of the properties of the harmonically trapped ideal Fermi gas, the chapter focuses on the effect of interactions, employing the local density approximation to calculate the density profiles and the momentum along the BCS–BEC crossover and comparing theoretical predictions with experiments.
Dynamics and Superfluidity of Fermi Gases
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter is devoted to discussing relevant dynamical and superfluid phenomena exhibited by interacting Fermi gases at low temperatures, with special focus on the strongly interacting Fermi gas at unitarity. The chapter discusses the predictions of hydrodynamic theory concerning the propagation of sound, the collective oscillations and the expansion of the gas after release of the trap. The Landau criterion for superfluidity and the behaviour of the dynamic structure factor are discussed. It also provides some considerations on the radiofrequency transitions as a method to observe pair-breaking transitions and to measure the pairing gap. The chapter discusses the behaviour of two-fluid hydrodynamics and the propagation of second sound as a tool to measure the superfluid density of interacting Fermi gases. It finally provides a brief summary of the rotational properties of the superfluid Fermi gas, like the quenching of the moment of inertia and the occurrence of quantized vortices.
Quantum Gases in Optical Lattices
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter discusses some features exhibited by quantum gases in the presence of periodic optical potentials (optical lattices). The behaviour of the single-particle excitation spectrum exhibiting the typical Bloch band structure is briefly summarized. The equilibrium properties of a Bose–Einstein condensate and of the ideal Fermi gas are discussed, with special focus on the behaviour of the momentum distribution. It also considers the effects of localization in one-dimensional quasiperiodic potentials and the nature of Bloch oscillations. The chapter discusses the structure of the elementary excitations in an optical potential, including the motion of the centre of mass in the presence of an additional harmonic potential. Finally, the chapter mentions the problem of quantum fluctuations, and it introduces the physics of the Bose–Hubbard and Fermi–Hubbard models, whose systematic investigation lies outside the scope of this book.
Quantum Gases in Pancake and Two-dimensional Regimes
Authors: Pitaevskii Lev , Stringari Sandro 
Published: March 2016

AbstractThis chapter addresses the question of quantum gases in two dimensions. It investigates both the pancake and the deep two-dimensional regimes. In the former case the gas is locally three-dimensional along the axial direction. In contrast, in the deep two-dimensional regime the axial motion is frozen. The chapter investigates the new physical phenomena exhibited by these two-dimensional quantum gases exploring the behaviour of the equation of state and of the collective oscillations. It discusses the behaviour of a fast-rotating Bose gas in two-dimensions, and the structure of vortex lines during the transition between the two-dimensional Thomas–Fermi and the lowest Landau level regimes. In the deep two-dimensional regime quantum gases exhibit novel and important phenomena at finite temperatures, due to the absence of long-range order and the emergence of the Berezinskii–Kosterlitz–Thouless transition. The peculiar behaviour of the BCS–BEC transition in deeply two-dimensional Fermi gases is also discussed.
Identifying Gossip
Authors: Eidinow Esther 
Published: March 2016

Abstract
Tracing the meaning of the term from its origins in Old English, to its current incarnation in social media, this chapter explores the ways in which gossip is understood to work, and how it becomes powerful within a community. A number of scholarly analyses of gossip are examined, using anthropological examples; recent theories in evolutionary psychology and neuroscience are also explored. More than just a process of information management, or of creating social cohesion, recent work suggests that gossip offers a method of making and sharing cultural meanings.
Genres of Gossip
Authors: Eidinow Esther 
Published: March 2016

AbstractBuilding on the previous chapter’s analysis of gossip as a social process, this chapter examines the language and locations of gossip in the ancient society of Athens. It sets the stage for the three chapters that follow, in which the presence of gossip can be traced in different kinds of ancient discourse. This chapter explores the ancient vocabulary of gossip, which offers insights into ancient perceptions of gossip; it draws attention to the places where gossip would circulate; and finally it looks at the ways in which gossip and gender were understood to be interrelated.
Gossip…In Public
Authors: Eidinow Esther 
Published: March 2016

Abstract
This chapter is the first of three case studies examining different genres of gossip, and the role and pathways of gossip in and through ancient Athenian society. This case study looks at ‘public’ forms of gossip, that is, the allegations or accusations produced by one speaker against another in forensic rhetoric. Focusing particularly on the distinction between gossip and slander (or diabole), it examines the relationship between gossip and oratory, and the ways in which the two genres coincide and overlap within and beyond the Athenian law courts.
Aesthetics
Authors: Nanay Bence 
Published: March 2016

Abstract
The claim defended in this chapter is that aesthetics is about experiences, so philosophy of perception is the natural place to turn if we want to engage with debates in aesthetics. This approach does not entail that all aesthetic phenomena are perceptual phenomena because philosophy of perception is about much more than just perception. Aesthetics is distinguished from philosophy of art, which has little to do with perception and experiences. This way of thinking about aesthetics can also avoid the complaints of the anti-aesthetics movements according to which aesthetics is either a narrow and somewhat irrelevant concept or so broad that everything would count as aesthetic. If we understand aesthetics in the light of philosophy of perception, we can avoid both of these potential problems.
Ctenophora
Authors: Simmons David K. , Martindale Mark Q. 
Published: March 2016

AbstractThe ctenophore nervous system is very complex with various specialized sensory cells, peripheral nerve nets, a centralized apical organ, neurons identifiable in all animal layers (epidermis, mesoglea, and gastrodermis), and with extensive regional specialization. The genomic content of nervous system genes (neural transcription factors, pre- and post- synaptic scaffold, neurotransmitter enzymes, and axon guidance genes) in ctenophores is the most reduced of any animal, more similar to that of the sponges, than to placozoans, cnidarians, and bilaterians. It is curious why ctenophores, but not sponges and placozoans, have such a highly diverse nervous system, even though sponges and placozoans have a larger number of genes traditionally thought to be involved with neural development and function. The proposed phylogenetic placement of the ctenophore divergence, at the base of the Metazoa, suggests that some form of a nervous system was already present at the ctenophore-extant animal split, and that this nervous system became exquisitely adapted for life as pelagic gelloplankton in ctenophores; while sponges and Trichoplax failed to exploit or lost this system. Conversely, ctenophores could have independently evolved their nervous system from the generic genetic components pre-existing in its extinct metazoan ancestors, and nervous systems were invented again by the cnidarian–bilaterian ancestor. Regardless, our current understanding of nervous system structure and genomic data from bilaterians, all four non-bilaterian phyla, and various protists, strongly suggests that ctenophores possess the absolute minimum genetic requirements for a functional nervous system of any animal. Consequentially, ctenophores are also most likely the oldest extant animal to possess a functional nervous system.
Xenoturbella
Authors: Stach Thomas 
Published: March 2016

Abstract
Xenoturbella is a taxon comprising two marine species. Xenoturbellids are worms with a simple body organization of up to 3 cm length that inhabit soft sediments between 40 and 300 m depth. In spite of an enormous interest in placing Xenoturbella phylogenetically, little is known about the biology of these animals. The entire nervous system of xenoturbellids is organized as a simple plexus within the epithelium of the epidermis. The plexus consists of neurons and sensory cells that are arranged in a more or less planar reticular pattern, intermingled between the basal parts of various cell types within the epidermis. Neurons in the epidermal plexus of xenoturbellids show immunoreactivity in studies with antibodies against serotonin, FMRFamide, and SALMFamides 1 and 2. In addition to neurons the plexus contains numerous sensory cells. The statocyst-like organ, situated at the anterior end of the animals, lies at the border between epidermis and mesoderm.
Kamptozoa (Entoprocta)
Authors: Wanninger Andreas 
Published: March 2016

AbstractKamptozoa is a group of 150 species of acoelomate, solitary or colonial, predominantly marine organisms that live epizooically on various substrates. Body size ranges from a few hundred micrometres to various millimetres, divided into a calyx and a stalk. Generally, the adult central nervous system consists of a dumbbell-shaped ganglion that is considered to be the fused once paired (‘cerebral’) ganglion. It is situated in the loop of the digestive tract and consists of a ventral neuropil mass with associated lateral somata. From the cerebral ganglion, all major neurites emanate; these do not seem to form distinct nerve cords. Numerous minute neurites penetrate the calyx and innervate ciliated sensory organs that are distributed all over the kamptozoan body, including the foot. There are two types of larvae: the planktotrophic swimming-type larva and the lecithotrophic creeping-type larva. Their neuroanatomies differ significantly. The nervous system of the creeping-type larva exhibits an astonishing degree of complexity. In particular, the apical organ consists of considerably more cells than that of most other spiralians. From the neuropil underlying the apical organ, a paired neurite bundle emerges which gives rise to one pair of ventral neurite bundles and one pair of more dorso-laterally positioned visceral neural bundles. The ventral neurite bundles are interconnected by commissures and have several, serially arranged sets of associated somata. Because of this tetraneuralin nervous system and numerous other characteristics, including the complex apical organ, a sistergroup relationship of Kamptozoa and Mollusca (Tetraneuralia) has been proposed.
Mollusca: Bivalvia
Authors: Wanninger Andreas 
Published: March 2016

AbstractWith approximately 15,000 described recent species, Bivalvia is the second largest molluscan class-level taxon. Compared to other conchiferan molluscs, the bivalve body plan has undergone several reductions, such as the lack of a distinct head including radula and buccal muscles, which is also reflected in the relatively simple nervous system exhibited by most bivalves. In autobranch bivalves, three pairs of ganglia are present: the cerebropleural ganglia (as a fusion product of the cerebral and pleural ganglia), the pedal ganglia, and the visceral ganglia. The pedal ganglia are often fused in the midline of the animal. Other ganglia such as, for example, buccal ganglia, are considered to be secondarily lost. The arrangement of the longitudinal nerve cords follows the molluscan-like tetraneural condition. The pedal ganglia are connected to the cerebropleural ganglia by two connectives. Bivalves have a remarkably high number of sensory organs, particularly at the mantle folds and in the oral region. The statocysts are situated within the foot and a paired osphradium, either innervated by an osphradial nerve from the visceral ganglion, or by a distinct osphradial ganglion, is often found. Photoreceptor cells or eyes may occur along the mantle margin, ranging from unicellular, cup-like ocelli to complex, lense-bearing eyes. Reliable data on bivalve neurogenesis and larval neuroanatomy are scarce. Larvae of Mytilus trossulus possess five serotonin-like and five FMRFamide-like cells in the apical organ. Taken together, the few data currently available permits no detailed comparison of neurogenesis in bivalves to that of other molluscs.