bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic heterogeneity of tumour celi populations
Authors: Woodruff Michael 
Published: November 2023

Abstract
The evolution of any population, whether of animals, plants or cells, depends on two essential elements: 1. Mechanisms for generating diversity among the members of the population. 2. Selection. Ecologists have long been concerned with how animals and plants interact with their environment, and with each other; indeed, this is their raison d’ être. Only comparatively recently, however, have tumour biologists become interested in studying tumour cell populations from an ecological point of view. In this chapter we shall consider firstly how phenotypic differences between individual neoplastic cells in a tumour may arise, and secondly how the cellular composition of a tumour may be affected by the reaction of the host, and by interactions between subpopulations of tumour cells.
Ecological classifications of bryophytes and lichens
Authors: During Heinjo J 
Published: November 2023

Abstract
Attempts to classify plants using common characters or responses to the environment are as old as botany (cf. Barkman 1988). Apart from taxonomical classifications, plants have been grouped into chorological types, sociological and ecological species groups, growth-forms, life-forms, and life-history strategies. Such classifications are useful for making comparisons of the ecology of species and communities in different geographical regions (Smith 1982).
Invasions and range expansions and contractions of bryophytes
Authors: Soderstrom Lars 
Published: November 2023

Abstract
Changes in bryoflora have occurred all over the world, but the documentation varies between regions. The changes are often induced by mankind, and many species, e.g. Bryum argenteum and Tortu/a muralis, have proliferated in man-made environments. Most parts of the world have received additions of species from other regions, e.g. the boreal hepatics Diplo phyllum obtusatum, Jungermannia sphaerocarpa, and Lophozia incisa in the tropics (Gradstein and V á na 1987) and the European Scleropodium purum and Thuidium tamariscinum in North America (Schofield 1988). Changes in the native flora involve, besides increases or decreases of abundance, both range expansions and range contractions. In this chapter, I give examples of changes in distribution ranges, mainly from Europe, and discuss the underlying mechanisms.
Ants and plants: a diversity of interactions
Authors: Huxley Camilla R 
Published: November 2023

Abstract
Interactions between ants and plants are extraordinarily diverse. Ants may act on plants as herbivores, defensive agents, seed dispersers, pollinators, or providers of macronutrients (nitrogen, phosphorus, potassium). Conversely, plants may supply a range of nutrients, or nest sites, or attract ants with chemicals which are secondary to the main metabolic processes. Many plants also exclude ants as pollinators, and certain carnivorous plants specialize in trapping ants. Among this wide range of interactions, the extent of benefit or loss to each participant depends critically on the local conditions, in particular the biotic environment. The defensive effect of ants, for instance, depends directly on the susceptibility of the pests of a plant to attack by ants. On the other hand ants often promote certain herbivores such as sap-sucking Homoptera and lycaenoid butterfly larvae.
Resource quality and cost in the foraging of leaf-cutter ants
Authors: Howard Jerome J 
Published: November 2023

Abstract
Leaf-cutter ant colonies may contain over a million workers and a thousand fungus gardens (Weber 1972), and to support these large colonies the ants continually search out and harvest suitable plants. However, ant colonies face limits to their ability to locate and harvest resources efficiently. At any given time most foraging workers are engaged in harvesting known resources, with only a small fraction searching for new resources (Johnson et al. 1987). Ants may attack plants over 100 m from the colony, and a single foraging trip may require several hours (Lewis et al. 1974; Hubbell et al. 1980). The time and energy required to locate and harvest rare or distant plants of high quality may, at times, make it more efficient for ants to harvest more readily available resources of lower quality.
Effects Of Ant-Homopteran Systems On Fig-Figwasp Interactions
Authors: Compton S G , Robertson H G 
Published: November 2023

Abstract
The pest status of many homopterans is often attributable to the ants that tend the bugs for honeydew and protect them from natural enemies (Buckley, 1987 a). If the ants tending the homopterans incidentally protect other herbivores, then the negative impact of the ants will be compounded (Fritz 1983). In South Africa, for example, red scale (Aonidiella aurantii Mask.) can devastate citrus orchards if ants are allowed to interrupt the biological control by parasitoids. The ants arc attracted by honeydew produced by soft scales, not by A. aurantii (Samways et al. 1982).
The Ant Community Associated With Extrafloral Nectaries In The Brazilian Cerrados
Authors: Oliveira Paulo S , Brandao Carlos R F 
Published: November 2023

Abstract
Schemske (1983) stressed that plants providing ‘limited’ resources for ants, such as extrafloral nectar, generally have a higher diversity of ant associates than those providing ‘major’ resources, such as nest sites and diverse foods. Since extrafloral nectar comprises only a part of the nutritional requirements of an ant colony, ant-guard systems mediated solely by the supply of nectar are usually very generalized (Schemske 1983; Beattie 1985).
Extrafloral Nectaries Of Herbs And Trees: Modelling The Interaction With Ants And Parasitoids
Authors: Koptur Suzanne 
Published: November 2023

Abstract
Plant tissue lost to consumers is a physiological cost to a plant. Over evolutionary time, a variety of plant defences have evolved which enable plants to avoid or better survive herbivory. Plants are rooted, and cannot flee, so their defences operate at the site of attack. Much research has been done on the mechanical and chemical defences of plants, but biotic defences have received less attention, perhaps because they require greater field study. Biotic defences of plants are dynamic, and there are compelling reasons to study them. Most plant species have multiple defences, since no single line of defence works against all herbivores. By gaining a better understanding of how plants benefit from mutualisms with biotic protective agents we gain insight into complex interactions that shape community structure.
Ground Beetles And Seed Dispersal Of The Myrmecochorous Plant Trillium Tschonoskii (Trilliacae)
Authors: Higashi Seigo , Ito Fuminori 
Published: November 2023

Abstract
Trillium species are myrmecochorous, perennial herbs occuring principally in woodlands of North America and eastern Asia, including Japan. The fruits of this genus contain several scores of seeds which are transported by such ants as Formica, Lasius, Myrmica, Aphaenogaster, and Camponotus, which are attracted to their juicy elaiosomes (Gates 1940, 1941; Berg 1958; Beattie and Culver 1981; Mesler and Lu 1983; Nesom and La Duke 1985). The present study involves Trillium tschonoskii Maxim., which grows in the cool temperate broad-leaved deciduous woodland of Hokkaido, northern Japan. This species is in full bloom in May, and in late July produces fruits containing about 80 seeds each. Each seed bears a juicy elaiosome about twice the size of the seed.
Brood Reduction In Gymnosperms
Authors: Haig David 
Published: November 2023

Abstract
Cannibalism in animals is often associated with the killing of an offspring by a parent or of one sibling by another. Similar phenomena occur in plants. Mothers abort seeds and ovules, and sibling embryos compete in a life-or-death struggle within seeds. For convenience, I refer to both processes as brood reduction. This chapter addresses the mechanisms and functions of brood reduction in gymnosperms, with a brief comparison to analogous processes in angiosperms. I emphasize gymnosperms because seed and ovule abortion in angiosperms have been extensively reviewed elsewhere (Stephenson 1981; Lee 1988). There is no conclusive evidence that gymnosperms utilize aborted ovules and defeated embryos as food, though this would clearly be adaptive in terms of the efficient use of resources. I discuss brood reduction in gymnosperms because these processes possibly have similar evolutionary causes to filicide and siblicide (associated with cannibalism) in animals.
Ropalidia fasciata in Okinawa, Japan: a species with flexible social relations
Authors: Itö Yosiaki 
Published: November 2023

Abstract
Ropalidia fasciata is a wasp that is common in South-East Asia, the islands of Okinawa, Japan, being the northern limit of its distribution range (Plates 1–4 ). In Okinawa, this species lives in grasslands, where tussocks of a large perennial grass, Miscanthus chinensis, grow scattered over short grass and herbs, and in sugar cane fields. The nests are hung from the leaves of M. chinensis or sugar cane, except in rare cases, when they are hung from the shoots of trees. I studied the social behaviour and social structure of this species in Okinawa-Hont6 (the main island of Okinawa) for a period of five years. A total of 374 nests, 646 foundresses, and 188 progeny females were marked.
Social relations in wasp colonies in the wet tropics: polistine wasps in Panama
Authors: Itö Yosiaki 
Published: November 2023

Abstract
In research in biochemistry or experimental biophysics, different researchers can obtain almost identical results by using similar apparatus for automatic chemical analysis or measurement of physical properties. Most descriptions of animal behaviour, however, are strongly influenced by the viewpoint and experience of the reasearcher (although there have been many attempts to standardize behavioural descriptions). Thus a social relation which I consider to be ‘mild’ may be described by another researcher as ‘aggressive’.In order to study the social relations of various tropical polistine wasps, I spent two months in 1982 conducting observations at the Smithsonian Tropical Research Institute on Barro Colorado Island, Panama (Plate 5). On and near Barro Colorado Island, I observed two species of Polistes—P. canadensis and P. versicolor—and two species of Mischocyttarus—M. angulatus and M. basimacula. I located nests of these four species and marked all the individuals on some nests. In other nests, only some of the individuals were marked. However, in both cases I could record precisely the frequency of dominance-aggressive acts among nest-mates.
Role of multiple comb construction and the perennial nature of nests: polistine wasps in Australia
Authors: Itö Yosiaki 
Published: November 2023

Abstract
In 1984, I had the opportunity to observe the social behaviour of polistine wasps in tropical and subtropical Australia. The Australian Polistinae consist of 12 species of the genus Polistes and 22 species of the genus Ropalidia (Richards 1978b), but there are only two species for which the social behaviour has been reported—P. humilis (Cumber 1951) and R. revolutionalis (Hook and Evans 1982).R. revolutionalis is a common paper wasp from the east coast of Queensland, Australia. Hook and Evans (1982) observed this species in Brisbane, near the southern limit of its distribution range, and reported that its colony cycle begins with the foundation of a single comb but, as the colony cycle progresses, each colony builds additional combs near the original one (see Plate 10).
Manipulation of progeny by mother groups: an hypothesis for the evolution of multi-queen societies
Authors: Itö Yosiaki 
Published: November 2023

Abstract
I stated in Chapters 9 and 10 that multi-queen societies may exist in most of the swarm-founding neotropical Polistinae (Polybia and closely-related genera), in at least some (possibly all) of the swarm-founding species of the subgenus lcarielia of the genus Ropalidia, and in some tropical Vespinae. Although their origins may in many cases be different from that of the Vespidae, the ants also have multi-queen societies, and they have at least one species in which all the females reproduce (Pristomyrmex pungens, Tsuji 1990). There is no hypothesis so far to explain the evolution or maintenance of such societies, in which dozens of reproductive queens, which are morphologically distinguishable from workers, coexist (although Rosengren and Pamilo 1983 discussed the environmental conditions necessary for the development of multi-queen, polydomous societies in Formica).
Protein motions: structural and functional aspects
Authors: Sneddon Scott F , Brooks III Charles L 
Published: November 2023

Abstract
5.1 Overview of protein motion
The ability of proteins to operate as catalysts clearly depends on subtle details of their structure. The overall shape and disposition of functional groups within an active site is what gives proteins some of their special properties: high substrate specificity, transition state stabilization, and the ability to transmit information to other units in a protein complex (allostery), to name but a few. As experimental and theoretical investigations have uncovered information about the structural component of protein function, so too have they shown that proteins exhibit a rich variety of motions (Gurd and Rothgeb 1979; Huber and Bennet 1983; Frauenfelder and Gratton 1986). If one considers just a few of the tasks proteins must per­ form in a living organism, it becomes apparent that motion, as well as structure, is an essential component of protein function. Receptor proteins lie partially buried in the cell membrane, and, on binding their target molecule, transmit this information into the cell by changing conformation, allowing the cell to respond to the external stimulus. Transport proteins (the oxygen transport protein haemoglobin, for example) bind ligands within their interior, releasing the ligand when conditions within the cell demand. The allosteric effects in haemoglobin involve motion of the subunits, while the entry and exit of the ligand requires an environmentally induced local con­ formational change (see Section 5.3.3). Many proteins are synthesized in a part of the cell distant from where they will perform their function. Transport of the protein from its point of manufacture to its point of use may require crossing membranes inside the cell. The folded protein is often too large to cross the membrane, and so must first unfold, traverse the mem­ brane as a linear sequence, and refold on the other side (see Section 5.2.4). Catalytic proteins (enzymes) must often provide a very specific, non­ aqueous environment for catalysis. Several known proteins completely engulf their substrate, perform the chemical reaction within the enclosed active site, then open to release the products.
Electron transporters
Authors: Mathews F Scott 
Published: November 2023

Abstract
7.1 Introduction
Electron transporters can be defined for our present purposes as low molecular weight (8–15 kDa) protein molecules that contain a redox active cofactor and have no catalytic function other than as an electron sink. There are four types of cofactors utilized by this protein class: haem, iron-sulphur centres, flavin mononucleotide (FMN), and copper. The cofactor, when bound to the protein, can normally exist in only two stable oxidation states. The protein environment can mediate the midpoint oxidation/reduction (redox) potential and establish the equilibrium level of the two states. In some cases (e.g. FMN or [4Fe-4S]) the cofactor is capable of existing in more than two redox states and the protein surroundings will regulate which pair of redox potentials are available under physiological conditions for the electron transfer process.
The primary function of the electron transporters is to transfer a single electron from one protein or protein complex to another. The electron donor protein is often a soluble protein while the acceptor is usually membrane bound. The acceptor or donor is also usually an enzyme catalysing an oxidation or reduction reaction, but another electron transporter can often serve as acceptor or donor.
Allosteric enzymes
Authors: Stevens Raymond C , Lipscomb William N 
Published: November 2023

Abstract
8.1 Allostery
8.1.1 Basic tenets of allosteric behaviour
The term allosteric (Greek, alios = other, steros = solid or space) is an ill-defined term used to describe the behaviour of numerous proteins. Webster’s dictionary defines allosteric as ‘of or having to do with a protein or structure that is altered reversibly by a small molecule so that its original function is modified’. Biochemistry textbooks define allostery as the behaviour of those proteins which do not kinetically conform to the ‘classical’ Michaelis-Menten model.
The genetic code-history
Authors: Osawa Syozo 
Published: November 2023

Abstract
The history of the research that led to the deciphering of the universal genetic code is interesting in view of how this most fundamental problem was solved, and how scientists were excited by this, one of the monumental achievements of this century. I must confess that I am not in an ideal position to review this history, as I played only a small part in it, and was certainly not a member of the ‘RNA Tie Club’ (Crick, 1968). Therefore, the next section-’The day before yesterday’-is written largely from a series of review articles by Francis Crick (1958, 1963, 1968), who has been playing the leadership-role in the coding problem, on our review article (Osawa et al., 1992), and on a comprehensive review by Jukes (1977b).
Anticodon composition
Authors: Osawa Syozo 
Published: November 2023

Abstract
The number of anticodons is always less than the total number of amino acid codons (of which there are 61), although the precise number varies; the smallest is 22 (in vertebrate mitochondria) and the largest possible is 46, although no organism has this many. The recognition pattern of a synonymous codon set by tRNA shows considerable variation between organisms. The anticodon composition lists for various organisms and organelles are given in Tables 3.1 to 3.5. The variations seen result sometimes from codon usage and sometimes from the tendency to reduce the genome size (genomic economization). In some cases, certain codons and the corresponding tRNAs disappear from the genome (see Sections 5.1 and 5.2).
Codon usage
Authors: Osawa Syozo 
Published: November 2023

Abstract
It should be safe to assume that two synonymous codons in a 2-codon set, or four in a family box, are used evenly. However, there are almost no such examples. Synonymous codon usage is not ‘symmetrical’. It is more or less, and sometimes extremely, uneven in any gene in a single species. Several factors affect codon usage, one of which is the genomic G + C content of the organism, another is the amount and composition of isoacceptor tRNAs that translate the codons.
The evolving genetic code
Authors: Osawa Syozo 
Published: November 2023

Abstract
The ‘universal’ genetic code was established experimentally in around 1966, mainly by the use of E. coli systems. This code was thought to be common to all organisms and viruses, because it was the same in some very different organisms (e.g. yeast, vertebrates, and tobacco mosaic virus). Such apparent universality of the code led Crick to propose the frozen-accident theory. Crick (1968) states that: ‘This accounts for the fact that the code does not change. To account for it being the same in all organisms one must assume that all life evolved from a single organism (more strictly, from a single closely interbreeding population)’. The theory further states that the proteins had become so sophisticated in a single pool of progenote cells that any changes in codon meaning would disrupt proteins by making unacceptable amino acid substitutions throughout their sequences, so that evolution of the code stopped, i.e. the code was frozen. ‘In its extreme form, the theory implies that the allocation of codon to amino acids at this point was entirely a matter of chance’ (Crick, 1968).
Elements of the Structure of Ribulose-P2 Carboxylase/Oxygenase Affecting Substrate Partitioning
Authors: Gutteridge Steven 
Published: November 2023

Abstract
A combination of mutagenesis and crystallographic analysis is being used to unravel the processes leading to fixation of atmospheric CO2 by photosynthetic organisms. The first steps in this complicated chemistry are due to one protein entity, ribulose-P2 carboxylase/oxygenase (Rubisco) that mediates at least five distinct chemical reactions commencing with binding of ribulose-P2 to 3P-glyc erate release (for recent reviews see Hartman 1992; Gutteridge 1990; Andrews and Lorimer 1987). An analysis of the fate of the atoms of substrate molecules as they proceed to product indicates that the intermediates generated during catalysis will have C centres with quite different geometries. Since all the reactions occur at a common site, then the enzyme must be flexible enough to retain each of the intermediates until the first stable product, 3P-glycerate is generated. For example, Fig. 3.1 shows the partial reactions leading to P-glycerate forma tion and the stereochemistry of the intermediates. Planar configurations of C2 and C3 centres of the bisphosphate alternate with tetrahedral conformers as the reaction proceeds to completion.
Tests and Models of Mechanisms for Biotin Dependent Carbon Dioxide Fixation
Authors: Kluger Ronald , Tsao Belinda 
Published: November 2023

Abstract
Carbon dioxide is the primary by-product of biological oxidative metabolism. This product is part of the biosphere and is dealt with by living systems in a number of ways, all of which provide useful materials for the organisms involved. Plants provide a general bank for carbon dioxide acquisition and a reductive photosynthetic apparatus to convert carbon dioxide into carbohydrates with oxygen as a by-product. There also exist nonreductive biological processes in which carbon dioxide is formally extracted from bicarbonate, at the expense of ATP hydrolysis, and transferred to a substrate where it replaces a proton. Since carbon dioxide is easily transferred between species in the air or in aqueous solution (as bicarbonate), there is ample opportunity for carbon dioxide which is given off by one species to be utilized by another. Enzymes which pro mote this class of reaction require special chemical assistance. This assistance is provided by the coenzyme biotin and the mechanism by which this assistance is administered is a fascinating problem in enzyrnic reaction mechanisms. While many of the characteristics of enzyrnic reactions involving biotin are under stood, the detailed pathway of the reaction is inferred rather than established and a number of ambiguities remain to be resolved. This chapter will review the status of some research on the mechanism by which carbon dioxide from dis solved bicarbonate is transferred to biotin.
Stoichiometric and Catalytic Activation of Carbon Dioxide on Transition-Metal Complexes
Authors: Behr Arno 
Published: November 2023

Abstract
A very promising approach to the activation of carbon dioxide is offered by its coordination to transition-metal complexes. In this chapter a brief insight is given into both stoichiometric and catalytic activation of CO2. Both parts are linked together very closely, because catalytic reactions can only occur if stoichiometric activation steps first start the reaction.