bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular Gas, Starbursts and Active Galactic Nuclei
Authors: Boothm Roy S , Aalto Susanne 
Published: November 2023

Abstract
Active centres of galaxies range from extremely compact active galactic nuclei (AGNs) powered by mass accretion on to black holes to extended starbursts of more modest power. In some extreme cases, e.g. Arp 220, the star-powered luminosity may rival that of a compact AGN. Interest in the connection between the starburst phenomenon and the central AGN has been stimulated by the fact that some galaxies with central AGNs, e.g. NGC 1068 and Centaurus A, contain significant amounts of circumnuclear gas. Molecular gas fuels the star-forming activity and responds physically and chemically to the ultraviolet radiation and supernovae produced in a young population of massive stars. Molecular clouds collide dissipatively and thus sink readily towards the centres of galactic gravitational potentials and may fuel the black holes. The high velocity resolution together with the modest angular resolution achievable in millimetre wave emission line measurements have made molecular emissions useful reddening-free tracers of the central kinematics of galaxies. Indeed, more recent high velocity, high angular resolution VLBI observations of molecular masers have revealed a very close connection between molecules and accretion discs surrounding AGN black holes.
Water Molecules in the Circumnuclear Regions of Active Galaxies
Authors: Neufeld David A 
Published: November 2023

Abstract
The circumnuclear regions of active galaxies are perhaps the most remarkable astrophysical environments in which molecules have been observed. LuminQUS maser emissions in the 616-523 22 GHz line of water have now been detected from at least 18 active galaxies; in every case where the size of the emission region has been determined, the water maser emission has been found to originate primarily within a parsec- or subparsec-sized region that is coincident with the active nucleus of the galaxy.
Modulation spectroscopy of the Group III nitrides
Authors: Pollak Fred H 
Published: November 2023

Abstract
Modulation spectroscopy is a powerful and versatile optical technique for obtaining valuable information about a large variety of semiconductor systems [1-9], including bulk/thin films, micro- and nanostructures (quantum wells, multiple quantum wells, superlattices, quantum wires, quantum dots), surfaces/ interfaces (semiconductor/ air (vacuum), semiconductor/semiconductor (hetero- and homojunctions), semiconductor/metal, semiconductor/ electrolyte), and the effects of growth/processing, as well as the characterization of actual device structures (heterojunction bipolar transistors, pseudomorphic high electron mobility transistor, quantum well lasers).
Cubic group III nitrides
Authors: Brandt Oliver 
Published: November 2023

Abstract
The Group III nitridest are, because of their large ionicity, among the most extreme representatives of compound semiconductors which, at equilibrium, condense in the wurtzite (a) structure only (Lawaetz 1972). It was, conse¬ quently, thought to be virtually impossible to force any of the Group III nitrides into the metastable zincblende ( f3) modification. This belief was substantially hardened by the lack of substrate materials with a reasonably close lattice match which otherwise could provide the required epitaxial constraint. In striking contrast to these considerations, researchers using molecular beam epitaxy (MBE) or metalorganic vapor phase epitaxy (MOVPE) have succeeded within the last decade in synthesizing the zincblende modifications of GaN, AlN, and InN on various, highly mismatched cubic substrates such as Si, MgO, 3C-SiC/Si, and GaAs.
Dissipative Motion
Authors: Pismen L M 
Published: November 2023

Abstract
Our interest in dissipative vortex motion is largely motivated by the latter’s role in long-scale coarsening dynamics. In a typical situation, there would be a number of defects in a large region. If a typical distance between the nearest neighbors is small compared to the size of region, the latter becomes irrelevant and can be viewed as infinite. On the other hand, the distances between defects should far exceed the healing length, unless at very early stages of coarsening following a sudden quench. Far from defect locations, the system is likely to approach a uniform state, but, since the phase of this state is arbitrary, it would be different at far removed locations in an extended region.
Motion of Line Vortices
Authors: Pismen L M 
Published: November 2023

Abstract
U(l) topological defects in three dimensions are line vortices. Unlike a point vortex, a line vortex has a geometrical structure of its own, and its curvature plays a decisive role in its dynamics. Since the motion is related to the local geometry, it is advantageous to describe it in terms of intrinsic properties of a curve that do not depend on the choice of a coordinate system. We shall start therefore with a purely geometric description of the kinematics of curves in three-dimensional space.
Anisotropic Superfluids
Authors: Pismen L M 
Published: November 2023

Abstract
The 2d complex vector field gives the simplest example of an “unconventional” superfluid with a non-scalar order parameter and a more complex topology of the minimal manifold, capable of undergoing phase transitions between different nontrivial “vacuum” states, each possessing its own set of defects. We shall see, moreover, that phase transitions may take place within a defect core, which makes possible different vortex structures with identical topology. In this way, the 2d complex vector field can be viewed as a toy model of similar transitions in superfiuid 3He (Section 8.3). We shall consider these transitions in detail, since the 2d complex vector field model allows us to demonstrate on an elementary level that which requires extensive computations in more complicated systems.
The maintenance of genetic polymorphism in small island populations: large mammals in the Hebrides
Authors: Pemberton Josephine M , Smith Judith A , Coulson Tim N , Marshall Tristan C , Slate Jon , Paterson Steve , Albon Steve , Clutton-Brock Tim 
Published: November 2023

Abstract
In this chapter we seek to emphasize a particular virtue of island populations: they can be used to evaluate the population genetic processes responsible for changing allele and genotype frequencies, and hence levels of genetic variation. This virtue is distinct from the more commonly discussed merits of island populations for investigating speciation, which occupy most of the other contributions to this book, and for investigating loss of genetic variaton in island-hopping founder events, exemplified by Gilbert et al. ‘s (1990) investigation of California Channel Island fox (Urocyon littoralis) populations.
Island hopping in Drosophila: genetic patterns and speciation mechanisms
Authors: Hollocher Hope 
Published: November 2023

Abstract
Islands have always been attractive systems for the study of evolution, and in particular speciation, for a wide variety of reasons, the most obvious being that they tend to harbour numerous and splendidly diverse arrays of species not typically found in continental areas. These arrays are characterized by high levels of endemism. Therefore, it follows that islands represent conditions that are extremely conducive for repeated speciation. If we can understand which evolutionary processes are important for speciation on islands, we may be able to define general principles that are applicable to a number of different biological situations.
Radiations, communities, and biogeography
Authors: Grant Peter R 
Published: November 2023

Abstract
The preceding chapters discussed causes and mechanisms of speciation. The remaining chapters extend the discussion of speciation on islands and in island-like habitats to questions about the evolution of many species from the same ancestral stock. There is a change of scale in this transition; from the evolution of two species from one to the evolution of many species from one or a few.
Single-mode quantum optics
Authors: Loudon Rodney 
Published: November 2023

Abstract
The theory of the electromagnetic field quantization developed in Chapter 4 simplifies considerably for applications Lo many of the key experiments in quantum optics. Thus many experiments use plane parallel light beams whose transverse intensity profiles are not important for the measured quantities. Again, it is often sufficient in interpreting the data to consider the light beams as exciting a single mode of the field. The present chapter begins with the specialization of the quantization to single-mode excitations. The quantum theory is illustrated by its application to several varieties of single-mode state and the main features of number Cates, coherent states, chaotic statistical mixtures and squeezed states are derived.
Resonance fluorescence and light scattering
Authors: Loudon Rodney 
Published: November 2023

Abstract
The basic components of a light-scattering experiment include a scattering region, with the atoms of interest illuminated by a parallel beam of light, and a detector that measures the scattered intensity at some finite angle to the direction of the incident beam. The scattering at small angles is usually difficult to resolve from the transmitted incident beam itself, and it is convenient in many experiments to measure the light scattered at right angles. In high-resolution studies, the atoms may be injected into the scattering region in the form of a beam in the third mutually perpendicular direction, to minimize the Doppler broadening of the scattered light.
Nonlinear quantum optics
Authors: Loudon Rodney 
Published: November 2023

Abstract
The book so far is almost entirely concerned with linear optical processes, where the response of a material to incident light is described by its linear susceptibility and the rates of optical processes are proportional to the incident intensity. However, examples of nonlinear behaviour occur in the saturation of atomic transitions, discussed in §1.7, and in the power-broadened susceptibility, derived in eqn (2.8.6). Atomic saturation is also an important component in the laser theory of§§t.10 and 7.3. The expressions derived in these examples contain the electromagnetic energy density or photon number in denominators whose expansions include terms proportional to all positive powers of the optical energy. The higherorder, or nonlinear, terms are normally much smaller than the linear term for conventional light sources but their influence is often significant in experiments that use laser sources. The present chapter treats the effects of the nonlinear terms in modifying the properties of incident light beams.
Physical Overview
Authors: Monk Kathryn A , Fretes Yance de , Reksodiharjo-Lilley Gayatri 
Published: November 2023

Abstract
Nusa Tenggara and Maluku (NT&M) is unlike any other region in Indonesia. It encompasses innumerable volcanic and coral reef islands scattered through some of the deepest seas in the world, and has no large islands such as Java or Sumatra. The area of Java, 132,000 km, is six and one-half times that of the largest island in NT&M, Halmahera, at 20,000 km. This region occurs at the heart of the complex crossroads of two continents, Asia and Australia, and two oceans, the Indian and Pacific. While this strategic position is a result of geological history, the climate, hydrology, and soils must also be considered if the biological, social, and economic life of the region is to be understood. An excellent review of the physical features of NT&M is supplied by the Regional Physical Planning Programme for Transmigration (RePPProT) in both Indonesian and English, but this is not widely available (RePPProT l 989a,b). However, every Regional Development Planning Board (Badan Perencanaan Pembanguan Daerah: BAPPEDA) in each provincial capital should hold a complete set of the relevant RePPProT reviews and maps.
Land Resource Use: Agriculture
Authors: Monk Kathryn A , Fretes Yance de , Reksodiharjo-Lilley Gayatri 
Published: November 2023

Abstract
Agriculture is the mainstay of the economy of Nusa Tenggara and Maluku (NT&M), with more than 80% of the population dependent on cultivation or animal husbandry (RePPProT 1989a). This necessarily means that understanding agricultural systems within NT&M is essential for the management of nearly 40% of the land and for improving the lives of most of the people of the region.
Introduction and basic concepts
Authors: Matoušek Jiří , Nešetřil Jaroslav 
Published: November 2023

Abstract
In this introductory chapter, we first give a sample of the problems and questions to be treated in the book. Then we explain some basic notions and techniques, mostly fundamental and simple ones common to most branches of mathematics. We assume that the reader is already familiar with many of them or has at least heard of them. Thus, we will mostly review the notions, give precise formal definitions, and point out various ways of capturing the meaning of these concepts by diagrams and pictures. A reader preferring a more detailed and thorough introduction to these concepts may refer to the book by Stewart and Tall [8], for instance.
Generating functions
Authors: Matoušek Jiří , Nešetřil Jaroslav 
Published: November 2023

Abstract
In this chapter, we are going to present a useful calculation technique. The basic idea, quite a surprising one, is to consider an infinite sequence of real numbers and associate a certain continuous function with it, the so-called generating function of the sequence. Problems about sequences can then be solved by calculations with functions. In this introductory text, we will only get to simpler examples, whose solution can mostly be found also without generating functions. In some problems, various tricks can reach the goal even quicker than the method of generating functions (but it may not be easy to discover such tricks). This should not discourage the reader from learning about generating functions, since these are a powerful tool also for more advanced problems where other methods fail or become too complicated.
Applications of linear algebra
Authors: Matoušek Jiří , Nešetřil Jaroslav 
Published: November 2023

Abstract
Linear algebra is a part of algebra dealing with systems of linear equations, matrices, determinants, vector spaces, and similar things. We have already seen several proofs using linear algebra in previous chapters, most notably in Section 7,5. Here we will demonstrate few more methods and applications. First, we present two problems, one concerning the existence of so-called block designs and the other about covering a complete graph by complete bipartite graphs. Hardly anyone would suspect that these problems are related to matrices, and yet an elegant solution can be given based on the notion of rank of a matrix. An interested reader can find much more about similar proofs in the very vividly written textbook by Babai and Frankl [12]. In the subsequent two sections of this chapter, we assign several vector spaces to each graph; this leads to a com pact and insightful description of seemingly very complicated sets. Finally in Section 11.6, we consider two elegant algorithms where linear algebra blends with a probabilistic method.
Inner product spaces
Authors: Kaye Richard , Wilson Robert 
Published: November 2023

Abstract
In this chapter we consider ways of ‘multiplying’ two vectors in a vector space V to give a scalar. Such a product is called an inner product, or scalar product, and the theory is based initially on a familiar example (sometimes called the dot product) on three-dimensional vectors in ℝ3. To begin with, we consider real vector spaces, but we will consider complex vector spaces later on. The scalar product, inner product, or dot product, of two vectors in ℝ2 or ℝ3 is rather well known. We start this chapter with its definition and description of its main properties. Throughout this section, llvll will denote the length of the vector v in ℝ2 or ℝ3
Orthogonal bases
Authors: Kaye Richard , Wilson Robert 
Published: November 2023

Abstract
One important use of the standard inner product of ℝ 3 is that it allows us to distinguish between ‘nice’ bases such as the usual one where the basis vectors are orthogonal to each other and each has length 1, and others such as (1, 0, 0)T, (1, 1, 0)T, (1, 1, 1)T where this is not true. The main objective of this chapter is to show how to find such nice (or, as we shall call them, orthonormal) bases for a given finite dimensional vector space with an arbitrary inner product, and to study the properties of these orthonormal bases. This chapter concerns inner products on vector spaces, and all our vector spaces are over ℝ or ℂ throughout.
Self-adjoint transformations
Authors: Kaye Richard , Wilson Robert 
Published: November 2023

Abstract
This chapter combines material concerning quadratic forms with material from the previous chapter on diagonalization. Throughout, V is a finite dimensional vector space over ℝ or ℂ with an inner product &lt;|&gt;. The main goal in this chapter is to understand the nature of quadratic forms, symmetric bilinear forms and conjugate-symmetric sesquilinear forms on a finite dimensional inner product space V—in particular, how the form relates to the inner product on V. It turns out that the key to describing such a form is an associated linear transformation on V. The linear transformations here are of interest in their own right, and have the property of being self-adjoint (as defined below). They can be diagonalized using methods in the last chapter, and this diagonalization provides a complete description of the bilinear or sesquilinear form we are interested in.
Patterns
Authors: Ball Philip 
Published: November 2023

Abstract
There was always something a little different about meteorite ALH84001, found in 1984 on the icy Allan Hills of Antarctica. For one thing, it came from Mars---like only 11 other meteorites found around the world. But unlike these others, ALH84001 was old-and I mean four-and-a-half billion years old. The rock was formed when the Red Planet was newly born. But the most extraordinary aspect of this little lump of Mars did not emerge until August 1996, when scientists from NASA announced that it might contain signs of fossil life from our cosmic neighbour. Maybe my years at Nature magazine have exposed me to too many amazing ‘discoveries’ that vanish like morning mist under close scrutiny; but I felt in my bones that this claim would not stand the test of time. If I’m wrong (and I rather hope I am), this is one of the most significant discoveries of the twentieth century.
Principles
Authors: Ball Philip 
Published: November 2023

Abstract
I hope you have not been holding your breath in anticipation that in this final chapter I will disclose a grand; unifying picture of pattern formation. I had better start out by saying that I shall not be presenting one, since I don’t know that such a thing exists. Some physicists have in recent years encouraged an unfortunate aspiration towards grand unified pictures, but I fear we must accept that the world that we encounter, the world of real stuff that we see and touch, is far too messy for that. At the same time, it is far more beautiful. Perhaps it is a matter of taste, but I feel that there is much more wonder in a world that weaves its own tapestry using countless elegant and subtle variations, combinations and modifications of a handful of common processes than one in which the details become irrelevant, in which a few recondite equations are supposed to provide us with all we need.
Genetic diversity: do marker genes tell us the whole story?
Authors: Tregenza T , Butlin R K 
Published: November 2023

Abstract
To understand the variety of life and, more urgently, to decide how best to conserve it, biological diversity must be measured. Such an endeavor has two prerequisites: first, that we decide what we mean by diversity, and secondly that we are able to quantify the differences between organisms, concentrating on those differences we believe to be most relevant. Because species are the units ecologists are best able to count (Magurran 1988), they are frequently used as a practical measure of diversity. This ought to mean that the still unresolved search for a universal species concept (Claridge et al.1997) should be placed at the center of ecological debates about biodiversity. However, practising ecologists usually cannot devote the time needed to tackle this thorny issue: they necessarily make pragmatic use of the species defined by systematists. There are essentially three classes of species concepts which can be applied to real situations. These are based either on diagnosability, reproductive isolation or ecological distinctiveness. When measuring alpha-diversity (the number of species within a community), which of these concepts is used is unlikely to affect estimates of diversity, except with a minority of species which present problems either of asexual reproduction or of hybridisation. Clones within asexual ‘ species ‘ may have different ecological roles (Vrijenhoek 1994), so if it is ecological distinctiveness which interests us, these clones may be more appropriate units than diagnosable species.
Sexual selection and natural selection 1n bird speciation
Authors: Price Trevor 
Published: November 2023

Abstract
Natural selection, sexual selection and random drift have all been postulated to play roles in the origin of species. Natural selection has the strongest empirical support, because rapid speciation is best documented in adaptive radiations: the more or less simultaneous divergence of numerous lines from a common ancestor to exploit new adaptive zones (Simpson 1953, p.223; Schluter 1998). Artificial selection experiments, mimicking natural selection, often produce reproductive isolation as a correlated response (Rice and Hostert 1993). Comparisons of sister clades with differing numbers of species have been used to identify traits which accelerate speciation rates. Heard and Hauser (1994) reviewed 47 proposed ‘key innovations ‘. Thirty-five (74%) were traits enabling exploitation of new resources (such as phytophagous habit in insects; Mitter et al.1988), 10 (22%) affected dispersal, and just two (4%) were related to sexual selection.
Sexual conflict and speciation
Authors: Partridge L , Parker G A 
Published: November 2023

Abstract
We discuss here the role of sexual conflict (or antagonism)-the different evolutionary interests of males and females- as a force regulating the potential for speciation. Although there has been awareness of sexual conflict and its ramifications for many years (e.g. Trivers 1972; Dawkins and Carlisle 1976; Dawkins and Krebs 1978, 1979; Parker 1979) there has been relatively little consideration of its possible implications for speciation (but sec Parker 1974a, 1979; Wilson and Hedrick 1982). Our emphasis will be on the evolution of reproductive isolation, because of its central importance in the speciation process. We shall consider the potential role of sexual conflict in the evolution of both pre and post-zygotic isolation. Conflict between the sexes can occur through two genetic routes (Chapman and Partridge 1996a). Sexual conflict within gene loci occurs when allelic variation at one locus affects a trait in both males and females, there are different trait optima for the sexes, and hence selection for sexual dimorphism. There will then be a genetic correlation between trait values in the two sexes through pleiotropycffccts of the same alleles on males and on females. The difference between selection on the alleles when in females and in males can therefore result in one sex constraining the evolution of the other (Slatkin 1984; Rice 1984; Lande 1987). For instance, high levels of re-mating in females may be of no direct benefit to females themselves, and may instead occur as a result of a pleiotropic genetic correlation between the sexes for mating frequency, and a correlated response in females to selection for frequent re-mating in males (Halliday and Arnold 1987).