bluuebunny/crossref_metadata_2025_split huggingface dataset:
Otitis media in Indigenous Australian children: review of epidemiology and risk factors
Authors: Jervis-Bardy Jake , Sanchez L , Carney A S 
Published: December 2013

AbstractBackground:Otitis media represents a major health concern in Australian Indigenous children (‘Indigenous children’), which has persisted, despite public health measures, for over 30 years.Methods:Global searches were performed to retrieve peer-reviewed and ‘grey’ literature investigating the epidemiology of and risk factors for otitis media in Indigenous children, published between 1985 and 2012.Results:In Indigenous children, the prevalence of otitis media subtypes is 7.1–12.8 per cent for acute otitis media, 10.5–30.3 per cent for active chronic otitis media and 31–50 per cent for tympanic membrane perforation. The initial onset of otitis media in Indigenous children occurs earlier and persists for longer after the first year of life, compared with non-Indigenous children. Indigenous children are colonised by otopathogens more frequently, at younger ages and with a higher bacterial load. Poor community and domestic infrastructure, overcrowding and exposure to tobacco smoke increase the risk of otitis media in Indigenous children; however, the availability of swimming pools plays no role in the prevention or management of otitis media.Conclusion:Despite awareness of the epidemiological burden of otitis media and its risk factors in Indigenous children, studies undertaken since 1985 demonstrate that otitis media remains a significant public health concern in this population.
Distributed coverage with mobile robots on a graph: locational optimization and equal-mass partitioning
Authors: Yun Seung-kook , Rus Daniela 
Published: December 2013

SUMMARYThis paper presents decentralized algorithms for coverage with mobile robots on a graph. Coverage is an important capability of multi-robot systems engaged in a number of different applications, including placement for environmental modeling, deployment for maximal quality surveillance, and even coordinated construction. We use distributed vertex substitution for locational optimization and equal mass partitioning, and the controllers minimize the corresponding cost functions. We prove that the proposed controller with two-hop communication guarantees convergence to the locally optimal configuration. We evaluate the algorithms in simulations and also using four mobile robots.
Changing aetiology of healthcare-associated bloodstream infections at three medical centres in Taiwan, 2000–2011
Authors: LAI C. C. , CHEN Y. H. , LIN S. H. , CHUNG K. P. , SHENG W. H. , KO W. C. , HSUEH P. R. 
Published: December 2013

SUMMARYThis multicentre surveillance study was conducted to investigate the trends in incidence and aetiology of healthcare-associated bloodstream infections (HCA-BSIs) in Taiwan. From 2000 to 2011 a total of 56 830 HCA-BSIs were recorded at three medical centres, and coagulase-negative staphylococci (CoNS) were the most common pathogens isolated (n = 9465, 16·7%), followed by E. coli (n = 7599, 13·4%). The incidence of all HCA-BSIs in each and all hospitals significantly increased over the study period owing to the increase of aerobic Gram-positive cocci and Enterobacteriaceae by 4·2% and 3·6%, respectively. Non-fermenting Gram-negative bacteria, Bacteroides spp. and Candida spp. also showed an increase but there was a significant decline in the numbers of methicillin-resistant S. aureus. In conclusion, the incidence of HCA-BSIs in Taiwan is significantly increasing, especially for Enterobacteriaceae and aerobic Gram-positive cocci.
The persistence of a chlorophyll spectral biosignature from Martian evaporite and spring analogues under Mars-like conditions
Authors: Stromberg J. M. , Applin D. M. , Cloutis E. A. , Rice M. , Berard G. , Mann P. 
Published: December 2013

AbstractSpring and evaporite deposits are considered two of the most promising environments for past habitability on Mars and preservation of biosignatures. Manitoba, Canada hosts the East German Creek (EGC) hypersaline spring complex, and the post impact evaporite gypsum beds of the Lake St. Martin (LSM) impact. The EGC complex has microbial mats, sediments, algae and biofabrics, while endolithic communities are ubiquitous in the LSM gypsum beds. These communities are spectrally detectable based largely on the presence of a chlorophyll absorption band at 670 nm; however, the robustness of this feature under Martian surface conditions was unclear. Biological and biology-bearing samples from EGC and LSM were exposed to conditions similar to the surface of present day Mars (high UV flux, 100 mbar, anoxic, CO2 rich) for up to 44 days, and preservation of the 670 nm chlorophyll feature and chlorophyll red-edge was observed. A decrease in band depth of the 670 nm band ranging from ∼16 to 80% resulted, with correlations seen in the degree of preservation and the spatial proximity of samples to the spring mound and mineral shielding effects. The spectra were deconvolved to Mars Exploration Rover (MER) Pancam and Mars Science Laboratory (MSL) Mastcam science filter bandpasses to investigate the detectability of the 670 nm feature and to compare with common mineral features. The red-edge and 670 nm feature associated with chlorophyll can be distinguished from the spectra of minerals with features below ∼1000 nm, such as hematite and jarosite. However, distinguishing goethite from samples with the chlorophyll feature is more problematic, and quantitative interpretation using band depth data makes little distinction between iron oxyhydroxides and the 670 nm chlorophyll feature. The chlorophyll spectral feature is observable in both Pancam and Mastcam, and we propose that of the proposed EXOMARS Pancam filters, the PHYLL filter is best suited for its detection.
An assessment of the 2011 Spanish pension reform using the Swedish system as a benchmark
Authors: VIDAL-MELIÁ CARLOS 
Published: December 2013

AbstractThe aim of this paper is to make an assessment of the 2011 reform of the public pension system in Spain using the Swedish pension system as a benchmark, although some reference to the US pension system is also made. The paper focuses on the reform, explaining its aims, breaking down the main contents, critically examining the official view and describing the expected ageing of the Spanish population. This approach complements the quantitative analyses performed by other researchers and will enable us to assess the reformed system with the focus on four main areas: actuarial fairness, actuarial transparency, solvency and communication with the public. The main conclusion is that the reform was a wasted opportunity given that Spain did not take advantage of the lessons learned in Sweden, it did not include any elements for improving the management of pay-as-you-go systems, and there is no sound basis for claiming that the system's sustainability is assured in the medium term, the long term or even the short term. The new parametric reforms currently under consideration in Spain are targeted to correct some of the pension system's design faults that have been highlighted in this paper.
Religion, Political Actors, and Democratization: The Turkish Case
Authors: Ozzano Luca 
Published: December 2013

AbstractThis article is part of a special issue on the five Muslim democracies. It aims at understanding the role played by religion, and particularly by religiously oriented actors, in Turkey's democratization processes. The first section analyzes the different theoretical approaches to the role of religion in democratization. The second section analyzes the different phases of Turkey's political history since the 1980 coup, taking into account both democratization processes and the role played by religious actors in the political system, and trying to understand the possible relations between the two phenomena.
1 Basic Dynamics of Point Particles and Collections
Authors: Johns Oliver Davis 
Published: December 2013

AbstractThis chapter begins with the assumption that Newton's three axioms refer fundamentally to the point particles of Newtonian physics, which are ‘incomparably harder than any porous Bodies compounded of them; even so very hard as never to wear or break in pieces; no ordinary Power being able to divide what God himself made one in the first Creation’. After deriving the laws of momentum, angular momentum, and work-energy for point particles, it will be shown here that, given certain plausible and universally accepted additional axioms, the same laws can essentially be proven to apply to macroscopic bodies, considered as collections of the elementary point particles. The chapter first considers the space and time in which motion takes place before discussing the laws of motion of point masses.
Hamilton's Principle
Authors: Johns Oliver Davis 
Published: December 2013

AbstractThis chapter shows that the general calculus of variations can be used to derive variational principles in mechanics. Two different, but closely related, variational principles are presented here: Hamilton's Principle and the phase-space Hamilton's Principle. It is believed by some authors that variational principles are the foundations of physics. For example, the classic analytical mechanics text of Landau and Lifshitz (1976) writes an action function on page two, and derives the whole of mechanics from it, including Newton's laws. Whether this is a fair judgment or not, it is certainly true that variational principles play a crucial role in quantum theory, general relativity, and theoretical physics in general.
7 Linear Operators and Dyadics
Authors: Johns Oliver Davis 
Published: December 2013

AbstractThis chapter introduces the concept of linear vector functions of vectors and the related dyadic notation, a concept that is particularly important in the study of rigid body motion and the covariant formulations of relativistic mechanics. Linear vector functions of vectors have a rich structure, with up to nine independent parameters needed to characterise them, and vector outputs that need not even have the same directions as the vector inputs. The subject of linear vector operators merits a chapter to itself, not only for its importance in analytical mechanics, but also because study of it will help the reader to master the operator formalism of quantum mechanics. The chapter begins with a definition of operators and matrices, and concludes with the Dirac Notation, used by quantum mechanics for complex vectors.
8 Kinematics of Rotation
Authors: Johns Oliver Davis 
Published: December 2013

AbstractThis chapter discusses and develops the techniques needed to define the location and orientation of a moving rigid body. Roughly speaking, rotation can be defined as what a rigid body does. For example, imagine an artist's construction consisting of straight sticks of various lengths glued together at their ends to make a rigid structure. As such a construction is turned in one's hands, or moved closer for a better look, one will notice that the lengths of the sticks, and the angles between them, do not change. Thinking of those sticks as vectors, their general motion can be described by a class of linear operators called rotation operators, which possess the special property that they preserve all vector lengths and relative orientations.
9 Rotational Dynamics
Authors: Johns Oliver Davis 
Published: December 2013

AbstractThis chapter studies in detail the natural motion of rigid bodies under impressed external forces and torques. The dynamical theorems of collective motion will be extended here by use of the rotation operators. The following sections discuss concepts such as the inertia operator and the spin, the inertia dyadic, and the kinetic energy of a rigid body. Any rigid body will have a system of principal axes. If necessary, three arbitrary body-fixed axes can be chosen, the inertia matrix can be calculated, and then the principal axis eigenvectors can be determined. In many situations of interest, however, the directions of the principal axes can be guessed with relative certainty from the symmetry of the rigid body. A number of rules that can be used are presented here.
Elementary Scattering Theory
Authors: Sivia D.S. 
Published: December 2013

Abstract
The opportunities for doing scattering experiments at synchrotron and neutron facilities have grown rapidly in recent years and are set to continue to do so into the foreseeable future. This text provides a basic understanding of how these techniques enable the structure and dynamics of materials to be studied at the atomic and molecular level. Although mathematics cannot be avoided in a theoretical discussion, the aim has been to write a book that most scientists will still find approachable. To this end, the first two chapters are devoted to providing a tutorial background in the mathematics and physics that are implicitly assumed in other texts. Thereafter, the philosophy has been one of keeping things as simple as possible.
Studying matter at the atomic and molecular level
Authors: Darwall Stephen 
Published: December 2013

Abstract
This chapter is based on the notion that the universe is made up of basic building blocks, with chemists such as Dalton and Mendeleev in the nineteenth century and physicists like Thompson, Rutherford, and Chadwick in the early part of the twentieth century reaffirming the concept of atoms. The focus here is on the study of condensed matter – liquids and solids – at the atomic and molecular level. Atoms cannot be seen by the naked eye due to the wave-nature of light, which bends around edges. The limit on seeing detail depends on the angular size of the object rather than its intrinsic dimensions. For example, while the diameter of the sun is 400 times larger than that of the moon, it has the same projection on the sky because it is also 400 times further away.
The basics of X-ray and neutron scattering
Authors: Sivia D. S. 
Published: December 2013

Abstract
This chapter discusses the basic concepts of X-ray and neutron scattering. For purposes of simplicity, the discussion will initially be limited to the case where there is no exchange of energy in the process. The scattering of an X-ray photon, or a neutron, by a sample is characterised by the resultant change in its momentum, P, and energy, E. The momentum and energy gained by the scattered particle is equal to that lost by the sample, of course, and vice versa. The definitions of P and E as ‘incident minus final’, rather than the other way around, is a matter of convention. An ideal scattering experiment consists of a measurement of the proportion of incident particles that emerge with a given energy and momentum transfer. This is encoded in a four-dimensional function S(P,E), traditionally called the ‘scattering law’, where the vector P has three components.
Liquids and amorphous materials
Authors: Sivia D.S. 
Published: December 2013

Abstract
This chapter focuses on liquids and amorphous materials that are characterised structurally by their localised order. Although ice, water, and steam are chemically the same material, they differ greatly in their physical properties. Below 0°C, and under normal atmospheric pressure, the water molecules are held in place by a regular and repeating network of hydrogen bonds, defined by its long-range structural order. At the other extreme, above 100°C, is steam – the random gaseous phase consisting of well-separated molecules. Water occupies the middle ground. While there is enough thermal energy in the system for the hydrogen bonds to be broken easily, there is still an electrochemically driven tendency for neighbouring water molecules to orient themselves in certain directions with respect to each other.
Periodicity, symmetry and crystallography
Authors: Sivia D. S. 
Published: December 2013

Abstract
This chapter delves into the crystalline state – the one occupying the top position in the hierarchy of the phases of matter. A look at elastic scattering with a consideration of the crystalline state gives rise to diffraction patterns with very sharp and clearly defined structure. As such, it is the field in which the earliest X-ray scattering experiments were conducted. Their inherently repetitive nature is the feature that endows crystalline materials with long-range order. In the chapter's analysis, the conclusion that the scattering from a crystalline sample is non-zero only at sharp well-defined points in Q is arrived at with the convolution theorem. The scattering from an ideal crystalline sample can be non-zero only for very specific values of Q; these isolated points of scattered intensity are known as Bragg peaks.
Operators in quantum mechanics
Authors: Galitski Victor , Karnakov Boris , Kogan Vladimir , Galitski, Jr. Victor 
Published: December 2013

Abstract
Mathematical formalism of quantum mechanics is closely connected with the theory of linear operators. A key quantum-mechanical principle is that physical quantities (observables) are represented by Hermitian linear operators that act on state vectors that belong to a Hilbert vector space. This chapter analyzes problems that deal with the basic concepts of the theory of linear operators; eigenfunctions, eigenvalues, mean values; the projection operators; quantum-mechanical representations of operators and wave-functions; and unitary operators.
Atoms and molecules
Authors: Galitski Victor , Karnakov Boris , Kogan Vladimir , Galitski, Jr. Victor 
Published: December 2013

Abstract
This chapter considers problems that deal with stationary states of one-electron and two-electron atoms; many-electron atoms (the statistical atomic model); principles of two-atom-molecule theory; atoms and molecules in external fields (interaction of atomic systems); and non-stationary phenomena in atomic systems.
Needles in a Haystack: the Class NP
Authors: Moore Cristopher , Mertens Stephan 
Published: December 2013

AbstractNP refers to a class of decision problems in which yes-instances are easy to verify. That is: a decision problem is in NP if, whenever the answer for a particular instance is ‘yes’, there is a simple proof of this fact. Given a graph, a Hamiltonian path is a path that visits each vertex exactly once. This chapter examines the NP class of problems, first by considering the proverbial task of finding a needle in a haystack. It then looks at several definitions of NP and discusses proofs, witnesses, and lucky guesses. It shows that NP encompasses a wide range of fundamental problems, from coloring maps to untying knots and satisfying systems of constraints. It describes some of the classic problems in NP and highlights some reductions between these problems by transforming questions about graphs into questions about Boolean formulas or vice versa. The chapter also analyzes primality in NP.
Counting, Sampling, and Statistical Physics
Authors: Moore Cristopher , Mertens Stephan 
Published: December 2013

AbstractThe objects that are solutions to an NP-complete problem are difficult to count. Counting can be a subtle and complex problem even when the corresponding existence and optimisation problems are in P. Spanning trees and perfect matchings are simple graph-theoretic objects, and the difference between them has deep mathematical roots. A matrix's determinant is the number of spanning trees while its permanent is the number of perfect matchings. Counting is closely associated with sampling. This chapter explores how to generate random matchings, and hence count them approximately, using a Markov chain that mixes in polynomial time. It considers the special case of planar graphs, such as the square lattice, to demonstrate that the number of perfect matchings is in P. It also discusses the implications of this fact for statistical physics and looks at how to find exact solutions for many physical models in two dimensions, including the Ising model.
When Formulas Freeze: Phase Transitions in Computation
Authors: Moore Cristopher , Mertens Stephan 
Published: December 2013

AbstractCertain formulas, such as the 3-SAT formula, undergo a phase transition from almost certain satisfiability to almost certain unsatisfiability when the number of constraints per variable reaches a critical threshold. This transition is comparable to the freezing of water and also occurs in many other NP-complete problems such as graph coloring and integer partitioning. This chapter first considers some experimental results on random 3-SAT and assumes that a phase transition exists. It then explores some simple phase transitions in random graphs and shows how to compute the size of k-cores, along with the degrees at which they first appear. It also looks at random k-SAT formulas and demonstrates how to prove upper and lower bounds on the critical density of clauses. Furthermore, it describes simple search algorithms as flows through state space before concluding with a discussion of recent advances inspired by techniques in statistical physics.
Processes in Microbial Ecology
Authors: Kirchman David L. 
Published: December 2013

Abstract
This book, which discusses the major processes carried out by viruses, bacteria, fungi, protozoa, and other protists – the microbes – in freshwater, marine, and terrestrial ecosystems, focuses on biogeochemical processes, starting with primary production and the initial fixation of carbon into cellular biomass. It then discusses how that carbon is degraded in both oxygen-rich (oxic) and oxygen-deficient (anoxic) environments. These biogeochemical processes are affected by ecological interactions, including competition for limiting nutrients, viral lysis, and predation by various protists in soils and aquatic habitats. The book links up processes occurring at the micron scale to events happening at the global scale, including the carbon cycle and its connection to climate change issues, and ends with a chapter devoted to symbiosis and other relationships between microbes and large organisms. Microbes have large impacts not only on biogeochemical cycles, but also on the ecology and evolution of large organisms, including Homo sapiens.
Elements, biochemicals, and structures of microbes
Authors: Kirchman David L. 
Published: December 2013

Abstract
Microbiologists know the basic biochemical make up of microbes, such as relative amounts of protein, RNA, and DNA in cells, while ecologists and biogeochemists use elemental ratios, most notably, the ratio of carbon to nitrogen (C:N), to explore biogeochemical processes and to connect up the carbon cycle with the cycle of other elements. Microbial ecologists make use of both types of data and approaches. This chapter combines both and reviews all things, from elements to macromolecular structures, that make up bacteria and other microbes. The most commonly used elemental ratio was discovered by Alfred Redfield, who concluded that microbes have a huge impact on the chemistry of the oceans because of the similarity in nitrogen to phosphorus ratios for organisms and nitrate to phosphate ratios in the deep oceans. Although statistically different, soil microbes have remarkably similar C:N ratios as the ratio of aquatic microbes. The chapter moves on to discuss the macromolecular composition of bacteria and other microbes. This composition gives insights into the growth state of microbes in nature. Geochemists use specific compounds, ‘biomarkers’, to trace sources of organic material in ecosystems. The last section reviews extracellular polymers, pili, and flagella, which serve a variety of functions, from propelling microbes around to keeping them stuck in one place.