bluuebunny/crossref_metadata_2025_split huggingface dataset:
Decay of GRs
Authors: Harakeh M N , van der Woude A 
Published: November 2023

Abstract
Since most GRs are located above the particle-decay threshold, they will mainly decay by particle emission, i.e. neutrons and protons, and in light nuclei also by a-particles. GR decay is a very valuable tool to learn about the microscopic damping mechanisms of these collective modes. Therefore, it is not surprising that there exists an extensive literature on experimental and theoretical studies of GR decay. Several review papers give a good overview of this kind of research - see (BER83, WAM88, KNO91, BER94a, BOR98). In a heavy nucleus charged-particle decay is strongly suppressed because of the Coulomb barrier so that for these nuclei particle decay occurs mainly by neutrons. γ-decay, although much weaker, is also possible. In general, such studies involve coincidence experiments of the type (x, x’ c) where c can be any kind of particle or a photon. The study of the decay properties of GRs is interesting for several reasons.
Protein Serine-Threonine Kinases
Authors: Kennelly Peter J , Edelman Arthur M 
Published: November 2023

Abstract
In nature, a broad range of proteins become modified via the covalent bonding of phosphate to nucleophilic functional groups located on the side-chains of their constituent amino acids. Although numerous amino acids can be modified in this way, by far the most widespread and quantitatively significant phosphorylation events take place on the hydroxyl groups of serine and threonine (Hunter 1991). Protein phosphorylation is a truly ubiquitous phenomenon, both in terms of the range of proteins modified-a murine fibroblast contains several hundred phosphoproteins (Levenson and Blackshear 1989) and a Escherichia coli contains over a hundred (Cortay et al. 1991)-as well as the diversity of organisms in which it has been observed. Virtually all living cells, regardless of function, habitat, or phylogeny, are sites of protein phosphorylation.
Inhibitors of Viral DNA Polymerase
Authors: Foster Scott A , Cheng Yung-chi 
Published: November 2023

Abstract
Viral DNA polymerase offers an attractive target for the development of anti-viral agents. Many DNA viruses encode a DNA polymerase. Examples include adenoviruses (AdV) (Challberg and Kelly 1989), poxviruses such as vaccinia virus (Moss 1986), and herpes viruses such as herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), human cytomegalovirus (CMV), varicella-zoster virus (VZV), and Epstein-Barr virus (EBY) (Roizman, and Batterson 1986). The DNA polymerase of these viruses is a key enzyme for their replication. Further, the viral DNA polymerases often differ enough from the host DNA polymerases to allow some degree of selective inhibition of the viral enzyme over the host DNA polymerases. In addition to the inherent differences between the viral and host DNA polymerases, specificity in inhibiting the viral DNA polymerase over the host enzymes can be achieved through the exploitation of other biochemical differences between infected and uninfected cells. Such differences could include membrane changes associated with the viral infection that allow anti-viral agents to penetrate infected cells more easily or metabolic changes that allow the selective activation of pro-drugs in infected cells.
Steroidogenesis Pathway Enzymes
Authors: Brodie Angel 
Published: November 2023

Abstract
The enzymes involved in the biosynthesis of cholesterol and steroid hormones are proving to be major targets for therapeutic intervention. Inhibitors of several of these enzymes have established clinical efficacy and are proving to be important in the treatment of disease. The most important of these enzymes and their inhibitors will be reviewed in the following sections. Figure 9A.1 of this chapter shows an abbreviated version of the biosynthetic sequence of cholesterol and steroid hormones from the three carbon units of mevalonate which are mediated by these enzymes.
Inhibitors of aromatase (oestrogen synthetase) and 5a-reductase have gained much attention in recent years in the treatment of steroid-hormone related disorders. Aromatase is an enzyme complex consisting of a cytochrome P450 haemoprotein and a ubiquitous electron-donating flavo protein, NADPH-cytochrome P450 reductase. The C19 androgen substrates androstenedione and testosterone bind to the P450 aromatase (P450 arom) which catalyses the aromatization of the androgen A ring and the loss of the C19 methyl group to yield oestrone and oestradiol (Cole and Robinson 1990).
DNA Topoisomerases
Authors: Foste! Jennifer , Shen Linus L 
Published: November 2023

Abstract
DNA topoisomerases are a class of enzymes that modulate the topo logical structure of DNA. Since the discovery of the first topoisomerase 20 years ago (Wang 1971), many of the properties of this class of enzymes have been elucidated and this progress has been the subject of many reviews (Cozzarelli 1980; Gellert 1981; Liu 1983; Drlica 1984; Wang 1985, 1987b; Maxwell and Gellert 1986; Yanagida and Wang 1987; Osheroff 1989a; Austin and Fisher 1990, Champoux 1990; Hsieh 1990;.Osheroff et al. 1991). In purified systems, topoisomerases relax supercoiled DNA, and can tie and untie DNA knots, and link and unlink catenated DNA circles. In eukaryotic cells, type I topoisomerases are associated with elongating transcription and replication forks, while type II topoisomerases are essential for segregating daughter chromosomes after DNA replication is complete (Yanagida and Wang 1987). Topoisomerases are also the target of a number of antineoplastic and antibacterial agents whose cytotoxic effects appear to arise from the stabilization of a complex between the topoisomerase and DNA (Ross 1985; Glisson and Ross 1987; Drlica and Franco 1988; Liu 1989; Smith 1990).
Inhibitors of Gastric H +, K+ -ATPase
Authors: Wallmark Bjorn , Keeling David , Lindberg Per 
Published: November 2023

Abstract
Acid-related diseases include reflux oesophagitis, duodenal ulcer, gastric ulcer, and the Zollinger-Ellison syndrome. These disorders are treated by a reduction of gastric acid secretion which can be achieved by surgery, antacids, or pharmacological agents. Several classes of antisecretory agent have been developed and introduced into clinical use. These include anti cholinergic compounds, such as pirenzipine, and the histamine H2-receptor antagonists (H2RAs), such as cimetidine (Black et al. 1972). The intro duction of cimetidine was followed later by other H2RAs, such as ranitidine and famotidine. In addition, stable prostaglandin analogues with antisecretory properties have been developed. However, these agents have been found to possess relatively weak ulcer healing properties (Nicholson 1985).
Fundamental Properties of the Neutron
Authors: Alexandrov Yu. A , Drozdova T F 
Published: November 2023

Abstract
The neutron is an elementary particle that has been extensively studied, both theoretically and experimentally. This book reviews and analyses the results of the mainly experimental research on the neutron and rationalizes what is known so far about its intrinsic properties. The book covers topics that have not previously been dealt with in detail, including the gravitational properties of the neutron, precise determination of its mass, beta-decay, and its electromagnetic properties. This translation is an updated version of the original Russian text and also covers the more recent advances made during the past 7-8 years, including the application of methods based on the storage of ultra-cold neutrons to the study of beta-decay, new precise measurement of the mass of the neutron, and confirmation of modern theories of the internal structure of the neutron.
Magnetic Moment of the Neutron
Authors: Alexandrov Yu. A , Drozdova T F 
Published: November 2023

Abstract
The neutron is a Dirac particle and according to the Dirac equation it must have a zero magnetic moment. However, at the beginning of the 1930s, as soon as the magnetic moments of the proton and deuteron had been determined, Esterman and Stern[168] showed that the obtained results led to a hypothesis of the neutron having a negative magnetic moment of about 2µN, where µN = eħ/2mp c is the nuclear magneton and mP is the proton mass. Tamm and Altschuler[169] were able to make an analogous suggestion on analysing the nuclear magnetic moments data. In 1937 Frisch et al.[170] made one of the first attempts to determine the magnetic moment of the neutron µn by observing the reorientation of the moments in a beam of polarized neutrons using an alternating magnetic field in resonance with the Larmor frequency of precession of the neutrons in a superimposed uniform magnetic field. The result of the experiment was more qualitative than quantitative and confirmed that the neutron magnetic moment is negative and approximately equal to 2µN.
Magnetic dichroisrn
Authors: Lovesey S W , Collins S P 
Published: November 2023

Abstract
Dichroism is the polarization dependence of the absorption of light. In general, the response of an electron charge distribution to an electromagnetic disturbance is anisotropic, due for example to the directionality of chemical bonds, crystal fields, and molecular orientation. Depending on the local symmetries exhibited by a material, this can lead to linear- and/or circular-polarization-dependent attenuation coefficients. Undoubtedly, the most famous example of linear dichroism at optical wavelengths is Polaroid sheet, in which oriented long-chain molecules absorb only the component of light which is linearly polarized parallel to the chains. Dichroism has been observed in a wide range of materials, at wavelengths extending up to hard X-rays. In the X-ray region, though, the effect is usually only significant very close to absorption edge resonances, where the excited photoelectrons are most strongly influenced by the internal fields of the absorber.
Resonant diffraction from antiferromagnets
Authors: Lovesey S W , Collins S P 
Published: November 2023

Abstract
The extreme weakness of magnetic X-ray diffraction compared with non-magnetic scattering, outlined in Chapter 2, presents a considerable challenge to experiments. Indeed, a great deal of effort has been deployed towards the goal of increasing the magnetic sensitivity of X-ray scattering. To this end, a fecund discovery (Namikawa et al. 1985) was a small, yet crucially important, resonance enhancement to the magnetic scattering from ferromagnetic nickel at wavelengths very close to the K-shell absorption edge (§6.2.3). This and the following chapter address the volume of work reported subsequent to the discovery.
Electronic energy bands: semiconductors
Authors: Balkanski M , Wallis R F 
Published: November 2023

Abstract
Pure semiconductors without deviations from periodicity have the important characteristic that at the absolute zero of temperature all energy bands up to and including a certain band are completely full of electrons and bands of higher energy are completely empty. There is a gap between the top edge of the highest filled band and the bottom edge of the lowest empty band. This gap is called the fundamental gap. The electrons occupying the lowest filled bands are strongly localized about individual nuclei and are termed core electrons. The electrons in the higher filled bands are less localized than core electrons and participate in covalent bonds between atoms. These electrons are valence electrons, and the bands they occupy are valence bands. For reasons that will become clear later, the bands that are empty at OK are conduction bands.
Electronic effects of impurities
Authors: Balkanski M , Wallis R F 
Published: November 2023

Abstract
Impurities can have a drastic effect on the properties of semiconductors, particularly the electrical properties. They can provide additional current carriers, such as conduction electrons or valence holes, and scattering centers which perturb the motion of the carriers. Impurities are conveniently classified according to the column of the periodic table in which they occur.
Bipolar iunction transistor
Authors: Balkanski M , Wallis R F 
Published: November 2023

Abstract
In Chapter 12 the p-n junction and the metal-semiconductor junction were discussed. These devices are two-terminal devices which are useful as rectifiers, but cannot be used as amplifiers because they contain no mechanism for modulating the electric current in such a way as to produce gain. What is needed is a third terminal to provide the necessary modulation.
Phonons in superlattices
Authors: Balkanski M , Wallis R F 
Published: November 2023

Abstract
We have seen in Chapter 7 that in a three-dimensional homogeneous crystal there are three frequency ranges of importance for the normal modes of vibration of the atoms. The low-frequency range contains the acoustic branches. In crystals containing two atoms per unit cell, the acoustic branches lie below an intermediate frequency range corresponding to a forbidden gap. The high-frequency range lies above the gap and contains the optical branches. Under certain circumstances, there may be no for-bidden gap even though optical modes exist. If there are more than two atoms per unit cell, there may be several forbidden gaps and several frequency ranges containing optical modes.
Metal-semiconductor devices
Authors: Balkanski M , Wallis R F 
Published: November 2023

Abstract
Among the most common heterostructures found in device applications are the metal-oxide-semiconductor (MOS) structure and the metal-semiconductor (MS) structure. The former is used in the metal-oxide-semiconductor capacitor and the metal-oxide-semiconductor field effect transistor, while the latter is the basis for the metal-semiconductor diode. These devices are referred to as unipolar devices, because current is transported by carriers of a single polarity, typically electrons. They are to be contrasted with bipolar devices such as the BJT which involve carriers of both polarities.
Group Theory in Subnuclear Physics
Authors: Stancu Fl 
Published: November 2023

Abstract
This book is a useful and accessible introduction to symmetry principles in particle physics. New ideas are explained in a way that throws considerable light on difficult concepts, such as Lie groups and their representations. This book begins with introductions both to the types of symmetries known in physics and to group theory and representation theory. Successive chapters deal with the symmetric groups and their Young diagrams, braid groups, Lie groups and algebras, Cartan's classification of semi-simple groups, and the Lie groups most used in physics are treated in detail. Gauge groups are discussed, and applications to elementary particle physics and multiquark systems introduced throughout the book where appropriate. Many worked examples are also included. There is a growing interest in the quatk structure of hadrons and in theories of particle interactions based on the principle of gauge symmetries. In this book the concepts of group theory are clearly explained and their applications to sub-nuclear physics brought up-to-date.
Elements of Group Theory
Authors: Stancu Fl 
Published: November 2023

Abstract
The purpose of this chapter is to familiarize the reader with the principal concepts of group theory. In order to prevent the presentation from becoming too abstract, examples of very simple groups are given. In later chapters these concepts are used for a detailed study of a selection of groups currently used in physical applications. For important topics of group theory not covered in this book the reader is referred to other books or detailed articles (see references).
linear Representations of a Group
Authors: Stancu Fl 
Published: November 2023

Abstract
In quantum mechanics we are interested in the properties of eigenstates under various transformations (Chapter 1 ). Group theory offers a systematic way of finding these properties from the symmetries of the Hamiltonian. The eigenstates form linear vector spaces which in terms of group theory provide matrix representations of the group of transformationsG under consideration. Let us denote byD(g) such a representation where g is an element ofG.
Basic concepts: Definitions and Axioms
Authors: Chandrasekhar S 
Published: November 2023

Abstract
Two lessons on Definitions and Axioms (or Laws of Motion) precede the formal opening of Book I: The motion of bodies of the Principia. In these two lessons, Newton formulates and elaborates the basic concepts and laws that are the underpinnings of his Natural Philosophy. The concepts are complex and are interrelated. And Newton’s Definitions and Axioms should be read in their totality and in their context keeping in mind that they ‘Shall be explained at large in the following treatise’ (for which end it was composed!). We shall quote rather more extensively than may be considered necessary; but they draw attention to issues that are commonly ignored; and Newton states his ideas with such clarity that it is a joy to learn them anew.
On the notion of limits and the ratios of evanescent quantities
Authors: Chandrasekhar S 
Published: November 2023

Abstract
In Section I, Book I of the Principia, Newton describes the elementary notions of differential calculus (without explicitly so stating) that are at the base of his entire treatment. And, as he explains in the Scholium at the end of the section, These Lemmas are premised to avoid the tediousness of deducing involved demonstrations ad absurdum, according to the method of the ancient geometers.
The law of areas and some relations which fallow
Authors: Chandrasekhar S 
Published: November 2023

Abstract
Since the equable description of areas indicates that there is a centre to which tends that force by which the body is most affected, and by which it is drawn back from its rectilinear motion, and retained in its orbit, why may we not be allowed, in the following discourse, to use the equable description of areas as an indication of a centre, about which all circular [circulatory]* motion is performed in free spaces? In this chapter we consider the propositions and lemmas in Section II, Book I of the Principia. These propositions and lemmas (as those of Section III) are, in the main, included in De Motu Corporum in Gyrum written in the summer of 1684 (cf. Chapter 1, §4) but not with the completeness or incisiveness as in the Principia.
A pause
Authors: Chandrasekhar S 
Published: November 2023

Abstract
By the end of Section IX, we again reach a watershed in the development of the Principia; and again, as at the end of Section III, we have a pause; but this time a shorter one addressed to ‘... “oscillating pendulous motions of bodies”‘. There is much of great interest in this section particularly in those parts dealing with cycloidal pendulums. But we shall pass them by as they are not in the mainstream of the development. But Propositions XLVI and XLVII are exceptions: Proposition XLVI provides an important generalization of Proposition XLII on the initial-value problem; and Proposition XLVII is a beautiful theorem which is at the base of another beautiful Proposition LXIV established in Section XI (see Chapter 12).
The three-body problem: the foundations of Newton’s lunar theory
Authors: Chandrasekhar S 
Published: November 2023

Abstract
In Propositions LXV-LXIX, Newton took the first steps in the study of the motions of three bodies under their mutual attractions. His main considerations are devoted to the changes in elements of a Kepler orbit effected by an external perturbation, in particular that of a distant third body. The considerations are clearly intended as a prelude to his lunar theory to be elaborated further, in Book III (Propositions XXVXXXIII; Chapter 22).
A digression into Opticks
Authors: Chandrasekhar S 
Published: November 2023

Abstract
These attractions bear a great resemblance to the reflections and refractions of light made in a given ratio of the secants, as was discovered by Snell; and consequently in a given ratio of the sines, as was exhibited by Descartes. Besides, it gave Newton the occasion to expand on his ‘query’ on the nature of light though he protests that in establishing Propositions XCIV-XCVI he was not at all considering the nature of the rays of light, or inquiring whether they are bodies or not; but only determining the curves of bodies which are extremely like the curves of the rays.
The figure of the Earth and of the planets
Authors: Chandrasekhar S 
Published: November 2023

Abstract
Newton’s consideration of the figure of the Earth and of the theory of the tides are towards this end: it is the gravitational attraction of the protuberant part of the Earth, caused by its own rotation or by the tidal action of the Sun and the Moon, that are the direct causes. And Newton’s absorption in the lunar theory derives in part from the same concern. The very nature of these problems requires a careful examination of the relevant data. Newton is conscientious in these matters. But in our account, we shall pass them by and restrict ourselves to the theoretical aspects and the basic theorems.
The lunar theory
Authors: Chandrasekhar S 
Published: November 2023

Abstract
he basic elements of the lunar theory have already been set out in the first seventeen corollaries of Proposition LXVI of Book I, albeit with only the barest indications of how they were established. In the fourteen Propositions, XVII, XXI-XXIII, and XXVI-XXXV in Book III (now to be considered), the theory is elaborated with derivations and applications to the perturbations of the orbit of the Moon about the Earth, caused by the tidal action of the Sun. Considering the wealth of information contained in these propositions, we shall first abstract their substance.
The precession of the equinoxes
Authors: Chandrasekhar S 
Published: November 2023

Abstract
Lemmas I, II, and III, culminating in Proposition XXXIX ‘to find the precession of the equinoxes’ is one of those sections, interspersed throughout the Principia, in which new ideas are formulated in the context of new problems that are constantly arising. In Lemmas I, II, and III, Newton introduces, for the first time, notions that are relevant to the dynamics of rigid bodies: the moment of inertia (which determines the ‘efficacy to wheel [a body] with circular motion about a centre’); the moment of momentum (which measures the ‘motions of the whole [body] about its axis of rotation’) and the torque-’the power to wheel about’--exerted by an external force on a non-spherical body; and, indeed, the principles underlying gyroscopic motion. All these notions are defined in the context of a dynamical theory of the precession of the equinoxes which derives from the oblateness of the Earth and the inclination of its axis of rotation to the plane of the ecliptic.
The solid of least resistance
Authors: Chandrasekhar S 
Published: November 2023

Abstract
In the Scholium to Proposition XXXIV, Newton formulates his problem of the solid of revolution which experiences the least resistance in moving through a ‘rare medium’ with a constant velocity in the direction of its axis. With hardly a hint of an explanation, Newton states an integral (which, as we shall presently verify, is a first integral of the appropriate Euler-Lagrange equations) and concludes with the assertion: ... the solid described by the revolution of this figure about its axis ... will be less than any other circular solid whatsoever, described of the same length and breadth.
The diffusion of momentum under various flow conditions
Authors: Guyon Etienne , Hulin Jean-Pierre , Petit Luc , Mitescu Catalin D 
Published: November 2023

Abstract
In the previous chapter, we have seen how heat-or miscible tracers-are transported by diffusion. The flux of heat, or of tracer, is then proportional to the gradient of the quantity being transported (temperature or tracer concentration) and directed along this gradient. the direction of the flux being such as to tend to attenuate the gradients. There exists another mechanism, often much more effective, of heat or tracer transport: convection through flow.