bluuebunny/crossref_metadata_2025 huggingface dataset:
The tropical shelterwood system
Authors: Matthews John D
Published: November 2023

The advantages of concentrated working and regeneration, as compared with fellings scattered far and wide over tracts of tropical moist forest, are so great that several attempts have been made to develop systems of regeneration based on the principles of the uniform system. The name given to these is the tropical shelterwood system. The tropical shelterwood system is an adaptation of the uniform system to tropical moist forest in which the seeding felling consists of a general opening of the canopy by cutting climbers and progressively reducing the middle tree storey by felling, girdling, or poisoning the unwanted trees (Robertson 1971). In converting from natural indigenous forest to more uniform high forest, the fellings recognized are generally of two kinds.
The coppice selection system
Authors: Matthews John D
Published: November 2023

In principle the working of the coppice selection system is similar to that of the selection system in high forest. An exploitable diameter is fixed according to the size of material required, and an estimate made of the age at which material of this size is produced; this age determines the rotation, which is divided into a convenient number of felling cycles, and the area is divided into annual coupes equal in number to the number of years in the felling cycle. Each year coppice fellings are carried out in one of the annual coupes, but only shoots that have reached exploitable size are cut, those below this size being left.
Burrows and burrowing behaviour of fish
Authors: Atkinson R J A , Taylor A C
Published: November 2023

The burrowing strategies of fish are reviewed. Excavatory techniques consist of excavation by mouth and displacement of sediment by body movements. The resulting burrows are structurally diverse, but may be divided into those in which the main development is horizontal and those in which it is vertical. Burrow function in fish and interspecific associations centred on fish burrows are discussed. The physicochemical environment of fish burrows is also considered and the physiological implications of a burrow-dwelling lifestyle are discussed.
The environmental impact of wood borers in mangrove swamps
Authors: Barkatl Sohail , Tirmizi Nasima M
Published: November 2023

Studies on marine wood-boring organisms including those infesting the mangrove vegetation are of recent origin. Investigations on marine wood-borers from the Indian ocean were initiated only after 1954 (Santhakumaran 1985). Literature concerning the mangrove wood-borers is reviewed by Santhakumaran (1983). Mangroves of Pakistan are severely damaged by wood-borers, in addition to other factors. Five molluscan borers and one crustacean have been recorded. The distribution, intensity and seasonal abundance of wood-borers from the mangroves of the Karachi coast have been extensively studied.
The environmental impact of subterranean mole rats (Spa/ax ehrenberg1) and their burrows
Authors: Heth Giera
Published: November 2023

The distribution, population parameters and subterranean way of life of the blind mole rats that belong to the Spalax ehrenbergi superspecies in Israel are briefly described. Special emphasis is given to the burrowing, burrow structure and underground foraging of the mole rats, which are direct causes of their environmental impact. A variety of the environmental effects of mole rats are discussed, including agricultural, arboreal and archaeological damage, the mounds as a site of natural disturbances, soil turnover and aeration, and the relationship between mole rats and geophytes, and between mole rats and other animal species. Most of the available information concerning these subjects is descriptive and circumstantial rather than quantitative. However, in view of the extensive geographical distribution of S. ehrenbergi mole rats in Israel, their frequency, and the results of their burrowing and food hoarding characteristics, it may be concluded that their environmental impact is substantial. Additional direct testing and experiment to determine the effects of burrowing on the soil features and the vegetation are needed, as well as more precise and comprehensive data on the agricultural damage caused by mole rats, in order to evaluate quantitatively the magnitude of their environmental impact. It is suggested, however, that efforts to control these pest rodents be confined to agricultural areas, since mole rats may have beneficial effects in the wild.
Progress in insect flight
Authors: Brodsky Andrei K
Published: November 2023

In the evolution of the Oligoneoptera, the tendency towards improved flight predominated over the tendency to improve the locking of the folded wings. With the complete metamorphosis characteristic of these insects, the function of feeding is accomplished by a poorly mobile larva, while winged imagos retain the functions of the search for a sexual partner and reproduction. The history of the Oligoneoptera began with the order Palaeomanteida (= Miomoptera), known from the Late Carboniferous until the Early or Middle Jurassic. The Palaeomanteida closely resembled the Hypoperlida in their general appearance and wing venation. On the other hand, certain features of the Palaeomanteida were similar to Blattinopseida-the latter had similarly stoutish bodies and a widened hindwing base.
The First European Settlements
Authors: Desmond Ray
Published: November 2023

Upon the dissolution of the Roman Empire, the Indian Ocean was not penetrated again by Europeans until the Portuguese challenged the commercial supremacy of the Muslim world in Asia. During the fifteenth century Portuguese sailors cautiously extended their exploration of the Atlantic coastline of the African continent, reaching Sierra Leone by 1460. Under King John II Lisbon had become a centre for African commerce, laying the foundations of an administrative structure which would promote Portugal’s future trade with the East. In 1487 Pedro de Covilha left Portugal on a secret mission to investigate the spice trade, then a Muslim monopoly. Disguised as a Moorish merchant, Covilha sailed from Aden to Cannanore on the Malabar coast, becoming in 1488 the first Portuguese to set foot on Indian soil. Also in 1487 Bartolomeu Diaz sailed out of Lisbon harbour with three small ships to continue the exploration of the African seaboard. They were the first European vessels to round the Cape of Good Hope and, although Diaz’s apprehensive and mutinous crews forced him to turn back, the prospect of a route to the Indies had been established. Two years after the accession of Manuel I to the Portuguese throne in 1495, Vasco da Gama commanded four ships on a reconnaissance mission to India. At Mombasa on the east coast of Africa he engaged an experienced Arab pilot whose knowledge of the Indian Ocean brought the Portuguese fleet in May 1498 to Calicut, a prosperous Malabar port enjoying extensive trade links with the Arab world. When some curious Tunisian traders questioned the purpose of his visit, da Gama allegedly replied, ‘Christians and spices’. He learnt that ginger, pepper, and cinnamon were abundantly available, that the cinnamon was inferior to that grown in an island called Cillan (Ceylon), and that cloves came from distant Melequa (Malacca). He departed from Calicut in late August with a modest but valuable cargo of spices. A delighted King Manuel informed Ferdinand of Spain that da Gama had returned with jewels and ‘cinnamon, cloves, ginger, nutmeg, and pepper, as well as other kinds, together with boughs and leaves of the same’.
The Roxburgh Era
Authors: Desmond Ray
Published: November 2023

William Roxburgh’s successful management of the horticultural station at Samalkot made him an obvious candidate to succeed Kyd. Invited to Calcutta by the Governor-General, Lord Cornwallis, he was persuaded, albeit reluctantly, to accept the appointment as Superintendent of the Botanic Garden which, he told Banks, was ‘a good Indian orchard & nursery but of too great extent’. He collected his family from the South including, presumably, his young son John, boarded out with Father Christoph Samuel John (1747-1813) at the Tranquebar Mission. One gets a very distinct impression from the correspondence between Father John and Roxburgh that the missionary took leave of his charge with little regret: ‘he causes me more trouble [than] all the others together. I would certainly not keep him for any sum in a year & would have sent him back long since if my heart was not so much attached to you & if I was not determined to give you all satisfaction possible’. With prophetic insight he saw a promising future as a plant collector for this high-spirited and unacademic youngster; ‘his greatest skill & pleasure [is] to climb on the highest coconut trees like a squirrel. Then he may collect for you all plants; & seeds you wish from foreign countries being very fond of running about, but to describe them, will never become his business’.
A Dictionary of Concepts in NMR
Authors: Homans S W
Published: November 2023

This is the first book to provide a comprehensive explanation of the bewildering array of acronyms and technical terms which have crept into the literature in recent years. Aimed at chemists and biochemists who have only an elementary knowledge of NMR, it provides a clear description of the concepts and basic principles involved. Recent developments in two-dimensional NMR methods in liquids have had a significant impact on the study of biological systems, and detailed descriptions of the techniques currently available are given. Mathematical descriptions are used where appropriate, since in many cases this is the only medium rigorous enough to convey ideas that are quantum mechanical in nature. However the level of mathematical competence required is low, and the more complex aspects are fully explained in the text. The use of a dictionary format allows easy reference. Each term is explained in full, extensive cross-references are included, and suggestions for further reading are given at the end of many entries.
Diverse roles for retinoids in modifying skin, skin appendages, and oral mucosa in mammals and birds
Authors: Hardy Margaret H
Published: November 2023

A number of changes brought about in mammalian or avian skin by exposure to excess retinoids will be discussed in this chapter. Their investigation has revealed three distinct roles played by varying retinoid levels with respect to the differentiation and functions of skin and some related tissues; they will be presented in the order of their discovery. The first role is to modulate the differentiation of epidermis and other keratinizing epithelia towards either keratin synthesis or mucus production. The second role is to initiate totally new, functioning mucous glands—structures unknown in the skin of birds or mammals. The third role is to divert skin on the avian foot from one recognizable morphogenetic programme (scale formation) to a different, but equally recognizable one (feather production). The skin of adult mammals is not especially vulnerable to damage by overdosing with retinoids, although massive doses can greatly increase epidermal thickness (Moore 1957). Paradoxically, it was a study of the damage by excess vitamin A to skeletal development in chick limbs in organ culture that led to the accidental discovery by Fell and Mellanby of a more profound effect of the vitamin on developing skin (Fell and Melian by 1952, 1953). In the high vitamin A medium, the primitive epidermal layer on a fragment of 7-day chick embryo skin became a cuboidal, mucus-secreting epithelium instead of a stratified, squamous keratinizing one. Further studies in organ culture by Fell and collaborators (Fell and Mellanby 1953; Fell 1957; Fitton Jackson and Fell 1963) showed that ciliated and mucous cells differentiated on the surface of the stratifying epithelium, which then resembled the epithelial lining of mammalian nasal passages or trachea. The change, called a mucous metaplasia, persisted for more than 2 weeks in culture in the presence of excess retinoid. When the explant was then transferred to the more physiological retinoid level of the control medium, containing only fowl plasma and chicken embryo extract, the superficial mucus-secreting and ciliated cells were shed and a normally keratinizing epidermis differentiated from the underlying epithelial cells. If the chick embryos were slightly older when the skin was explanted to vitamin A medium, the metaplasia was reduced—there was no mucus secretion by the surface cells, but no keratinization of these cells either. In skin explants from still older embryos, in which the first keratinized cells were already appearing, excess vitamin A had no effect on the epidermis.
Malformations of hindbrain structures among humans exposed to isotretinoin (13-cis-retinoic acid) during early embryogenesis
Authors: Lammer Edward J , Armstrong Dawna L
Published: November 2023

Increasing evidence indicates that retinoic acid (RA) plays a major role in controlling the morphogenesis of many vertebrate structures. It is metabolically derived from retinol (vitamin A) and can mimic some, but not all, of retinol”s properties. For example, RA cannot support retinol’s role in reproduction or in the visual system (mediated by conversion of retinol to retinaldehyde), but it can promote cellular differentiation and bone growth as well as retinol does. Both retinol and RA are teratogenic in a number of experimental vertebrate species and humans (Kochhar 1967; Shenefelt 1972; Lammer et al. 1985; Irving et al. 1986; Webster et al. 1986; Rummler et al. 1990). Retinoic acid-induced malformations in humans have resulted from the inadvertent use of isotretinoin (13-cis-RA) during pregnancy (Lammer et al. 1985). Isotretinoin is an oral medication taken for the treatment of severe nodulocystic acne. In the United States, isotretinoin was initially marketed in 1982 and is approved only for the treatment of severe nodulocystic acne that is unresponsive to other therapies.
Somatic cell genetics and the search for colon cancer genes
Authors: Thomas H J W , Frischauf A-M , Solomon E
Published: November 2023

As this volume is in honour of Professor Sir Henry Harris, it seems appropriate, under the general topic of genetics of colon cancer, to focus specifically on the role of somatic cell genetics in the isolation of genes responsible for this disease. Two rather different types of somatic cell genetics have been used in the identification of the genes mutated in colon cancer. The first type might be called tumour somatic cell genetics and has developed from the fact that loss of genetic material from tumour cells can be detected either microscopically, as whole or partial chromosome loss or by loss of heterozygosity (LOH) (for reviews see Goddard and Solomon, (1993) and Lasko et al., (1991)). This genetic loss in tumours has come to be recognized as the hallmark of tumour suppressor genes. The second type of somatic cell genetics is the methodological one, in which the segregation of human chromosomes from interspecific hybrids, can be used both for mapping purposes and for the production of probes. Part of this methodology has evolved directly from experiments of Goss and Harris (1975) in which breakage of chromosomes through irradiation was used as a statistical mapping method. We and others have used both types of somatic cell genetics in various phases in the search for the adenomalous polyposis coli (APC) gene, as well as other colon cancer genes.
Mechanisms of transformation by HPV
Authors: Vousden Karen H
Published: November 2023

Cervical carcinoma has long been recognized as a sexually transmitted disease and, as described in Chapter 4, there is now extremely convincing epidemiological evidence that infection with certain types of genital human papillomaviruses (HPVs), known as the high-risk HPVs, contribute to the development of this cancer. The identification of some HPV types as oncogenic viruses has not solely been the result of epidemiological studies, however, and some of the most compelling evidence implicating the malignant potential of these viruses has been gathered from the study of in vitro transformation mediated by HPV DNA. Although the ability to efficiently transform cells in culture is, by itself, no safe indication that a virus has malignant potential in vivo (as illustrated by the adenoviruses), the identification and analysis of HPV-encoded oncogenes has reinforced the hypothesis that HPV infection plays a causative role in the development of most cervical cancers. More recently, an understanding of how the virally encoded oncoproteins function is paving the path towards the development of better prognostic and diagnostic tests, as well as prophylactic or therapeutic drugs and vaccines.
Principles and applications of complementary RNA probes
Authors: Steel J H , Gordon L , Polak J M
Published: November 2023

The use of in situ hybridization for the detection of messenger RNA (mRNA) in tissue sections and other types of tissue or cell preparations is widely accepted as being a powerful technique for investigating gene expression at the cellular level. The high specificity and sensitivity of the bond formed between the nucleic acid probe and its target in the tissue section allows the detection of low abundance mRNAs, although there is a detection limit for the technique. In this chapter, the use of complementary RNA (cRNA) probes will be discussed (for a discussion of other types of probes, see Chapters 1-3).
Complexities of Discovery
Authors: Walter Lack H , Mabberley David J
Published: November 2023

According to the Oxford English Dictionary,to discover means ‘to obtain sight or knowledge of (something previously unknown) for the first time’. In science, emphasis is placed on ‘the first time’: a vast literature exists on the actual priority of any given discovery, often with several contending candidates, few cases being as clearcut as the European discovery of the east coast of Australia by Captain James Cook or the ubiquity of the nucleus in plant cells by Robert Brown. Priority plays a particularly important role in taxonomy and nomenclature.
Sibthorp: The First Journey
Authors: Walter Lack H , Mabberley David J
Published: November 2023

ln order to comply with the regulations of his Radcliffe Fellowship. Sibthorp, the newly elected third Sherardian Professor, was obliged to spend three more years ‘beyond sea.’ The idea of a tour to the Ottoman Empire is not referred to in his correspondence and it may well have developed only during his stay on the Continent.
Hawkins: The Years Between
Authors: Walter Lack H , Mabberley David J
Published: November 2023

Hawkins had been a fortunate traveller. not having fallen ill on his journey nor having exhausted himself too much. All his relatives—his mother Anne. whom he probably visited first, bis brother, his sister and brother-in-law–were alive and probably well. His extensive collections seem to have arrived safely in England: some of them had been sent by ship, others probably taken in his personal luggage. There is no indication that they included anything other than min-eralogical and geological material. More will be said of the fate of these specimens in Chapter 15 (see pp. 18 3–6 ).
Sibthorp: The Second Journey
Authors: Walter Lack H , Mabberley David J
Published: November 2023

As with Sibthorp’s first journey, there is a diary of his second one, but there are extensive gaps in it; long stays in Istanbul and Zakinthos are not covered, nor most of the return journey, nor a few weeks of his travels in the Ottoman Empire, though the latter are fortunately included in Thoburn’s account. Sibthorp’s diary was written in the field, in his careless hand which is often very difficult to decipher, It is preserved, as MS Sherard 216, cited here as Sibthorp Diary 2, and MS Sherard 217, cited here as Sibthorp Diary 3, in the Department of Plant Sciences. Oxford, Whereas MS Sherard 216 is the complete original pocket-book for the first part of the journey (Fig. 46). MS Sherard 217 consists of various parts of the original notebooks bound together much later, when no attempt was made to arrange them chronologically, though continuous entries begin with 9 September 1794 and end on 12 October 1794; there are entries for only a few days of 1795.
The Collections, Drawings, and Notes
Authors: Walter Lack H , Mabberley David J
Published: November 2023

That matters in an expedition are the collections, drawings, and notes brought back. On Sibthorp’s and on Hawkins’s journeys ample material was collected and is summarized in this chapter. The publication of the results by Smith, Lindley, Hawkins. and Imrie is dealt with in Chapter 17.
The Sphecid Wasps(Sphecidae)
Authors: Hanson Paul , Menke Arnold S
Published: November 2023

Body length 2.0 to 50.0 mm; both sexes fully winged (except in the Old World subfamily Heterogynainae); sexual dimorphism slight, although heads, and to some extent legs, vary between the sexes, often strikingly so; colour variable; body vestiture simple, setae not branched or plumose. Antenna 12- segmented in females, 13 in males (infrequently 12); inner eye margins straight, arcuate, sinuate or notched. Pronotum joined to mesothorax immovably, its hind margin straight and typically separated from mesoscutum by a constriction that contributes to the formation of a characteristic raised collar; posterolat eral margin of pronotum produced into a rounded lobe that covers mesothoracic spiracle; pronotal lobe typically not attaining tegula, the mesoscutum and mesopleuron in broad contact there. Fore wing usually with numerous veins and enclosed cells, with a pterostigma; hind wing with enclosed cells, claval lobe present, jugal lobe usually present. Hind leg with cleaning pecten on inner side of basitarsus (absent in bees).
Conclusions: new research initiatives
Authors: Ligon J David
Published: November 2023

In this book I have attempted to review and synthesize the current literature dealing with two major aspects of the reproductive biology of birds, sexual selection and mating systems. In carrying out this project, I have gained a great deal of factual knowledge. I have also developed some impressions concerning the status of our understanding of these subjects, and where the field might go from here. These are discussed below.
Social networks and exchange
Authors: Johnson Brooke R
Published: November 2023

The Turkana people have adopted various levels of social interaction and strategies of livestock management that enhance their ability to survive in and exploit the arid scrub savanna environment they inhabit. The relative paucity and patchiness of rainfall require them to keep a variety of livestock. Vulnerability of the livestock to patchy vegetation, limited forage and water, endemic disease, and livestock raids from neighboring tribes requires the Turkana to maintain livestock-exchange and food-sharing relationships that provide a resource safety net. These relationships form an intricate social network that can extend throughout the district and beyond to other areas of the country. A Turkana social network is composed of cognates, affines, friends, and other livestock-exchange partners. In this chapter, the context of Ngisonyoka Turkana social networks is discussed based on a sample of 22 nomadic and settled herd owners.
Subsistence, activity patterns, and physical work capacity
Authors: Curran Linda S , Galvin Kathleen A
Published: November 2023

Health, nutrition, activity patterns. and physical work capacity are necessarily interrelated for pastoral nomads such as the Ngisonyoka Turkana. The extent of the Ngisonyoka Turkana’s nutritional stress. as described in Chapter 7, can only be assessed with detailed knowledge of their energy requirements as well as their energy intake. Energy requirements consist of basal metabolic needs and the energy demands of various subsistence tasks. Basal metabolic requirements vary as a function of age, sex, season, body size, body composition, and life stage. For example, women have additional energy costs associated with pregnancy and lactation; children, from the demands of growth and the presence of disease. During the dry season. adults buffer children against nutritional stress by allocating to them some of their own food resources. Beyond the basal metabolic requirements. additional energy required also varies according to season (households move more frequently during the dry season) and individual variations in access to food, as a function of age and social standing, or ‘seniority’. Each household’s previous herding successes or failures form the backdrop for individual nutrition and health histories. Though nominally an egalitarian society, the people recognize among themselves both richer and poorer households. Nutritional inadequacy can result from herd losses, resulting in fewer animals to support the household, or from a mismatch in herd labor requirements and available household members, leading to greater individual energy expenditures.
Damage to Flowers and Seeds
Authors: Butin Heinz
Published: November 2023

Flowers and seeds, in common with all plant tissues, can be damaged either by biotic or abiotic agents which, in classic plant pathology, are distinguished as the two principal causes of disease; either ‘parasitic ‘ or ‘non-parasitic ‘ disease, respectively. Among the most important abiotic factors which can damage flowers or inflorescences are extremes of weather, in particular late frosts which principally affect the early flowering trees like walnut, Sweet chestnut, beech, and oak. In these species, the damage is usually noticed only because of the failure of the seed crop but there are others, especially ornamentals, which can show striking changes directly after the first frosty night: in magnolias, for example, the normally white petals become an unsightly brown and hang down limply. Other weather events which can damage the flowers are hailstorms and sudden, dry winds (cf. p. 47).
Wood Damage in the Standing Tree
Authors: Butin Heinz
Published: November 2023

Forest fires can be one of the greatest causes of loss in forests since, at their most severe, they can wipe out entire stands by spreading through the forest canopy. Certain years come to be recognized as ‘forest fire years ‘ when persistently hot, dry weather brings an exceptionally high risk of damage. Information on fire risk factors and on prevention and control can be found in the specialist literature. Storm damage can take the form of ‘windthrow, ‘ when the whole tree is uprooted or of ‘wind snap, ‘ when the root anchorage is relatively firm, but the stem breaks under wind pressure which exceeds its bending strength. Windthrow, which progresses through a stand due to restricted rooting, is said to be ‘endemic, ‘ while extensive windthrow due to severe storms, regardless of site conditions is described as ‘catastrophic ‘. Storm damage destabilizes the forest ecosystem, sometimes favoring the build up of pests, especially bark beetles that can harm surviving trees or logs awaiting extraction in coniferous stands (227). Breakage due to ice or snow can occur when excessive accumulations build up in extreme winter weather. In the case of ice, accumulation occurs when supercooled rain freezes on contact with the tree. The weight of ice or snow can break leading shoots as well as branches. Pines, spruces, Silver fir, Cedar of Lebanon, and beech are particularly at risk.
Changes in Habit and Growth Abnormalities
Authors: Butin Heinz
Published: November 2023

Every plant species varies within certain limits in the expression of its specific growth habit and the form of its component parts. The extremes of this variation occasionally attract attention but are not regarded as pathological changes. Such deviations are caused by various abiotic or biotic factors. Thus, for example, a light-demanding tree species grows with a bent stem if the light source is one sided. Similar responses can be caused by the wind blowing predominantly from one direction. Animals can bring about various changes in form, such as the bushy growth which follows browsing by deer. Finally, plants too can influence the growth habit of trees; e.g. the stem constrictions and twisting caused by Lonicera periclymenum (honeysuckle). All these examples are induced by external factors and represent morphological adaptation within the basic pattern which is characteristic of that particular tree.
Roads and road transport: their impact on the countryside-and what should be done about it
Authors: Dower Michael
Published: November 2023

Michael Dower has been Director-General of the Countryside Commission since 1992. He took his MA at St John ‘.I• College, Cambridge, and then studied for a Diploma in Town Planning, which he was awarded in 1957 at University College, London. He then held a succession of posts in planning and development: with the London County Council, the Civic Trust, the United Nations Development Programme for Ireland, and the Dartington Amenity Research Trust and Darting  ton Institute in Devon, of which he was Director for 17 years, until 1985. Mr Dower then served as National Park Officer to the Peak Park Joint Planning Board until he was appointed to his present post. He has been a member of the Sports Council and of the English Tourist Board, and he was President of the European Council for Village and Small Town from I986 to I990. He is the author of several books and articles about the British countryside and its preservation.
The complex molecular network regulating tumour angiogenesis: the importance of context
Authors: Lewis Claire E , Balkwill Frances R
Published: November 2023

Since the early descriptions of angiogenesis in malignant tumours some 25 years ago (1,2), over 3000 papers have been published describing the involvement of myriad individual factors in the various cellular steps of the angiogenic pathway. These include cytokines, enzymes, and other macromolecules which regulate the dissolution of the basement membrane around existing vessels, and the orientation, motility, proliferation, and differentiation of endothelial cells to form new ones (3).
Vascular targeting of anti-cancer gene therapy
Authors: Jaggar Rhys T , Bicknell Roy
Published: November 2023

In anti-cancer gene therapy we have the opportunity to be destructive rather than correctional and for this reason anti-cancer studies are likely to comprise a major area of gene therapy research in the near future. Nevertheless, there are many problems to be surmounted. Foremost among these is that of delivery of the gene to the cell in which function of the gene product is required. The cells of the vascular endothelium are some of the most accessible in the body, comprising a single monolayer which are all in intimate contact with the blood. This makes vascular targeting of gene delivery systems a particularly appealing strategy.
The inland waters
Authors: Fogg G E
Published: November 2023

There is great variety in the inland waters of the polar regions (Hobbie 1984). It was convenient to consider those contained in ice in Chapter 3, but there is no sharp biological distinction between these and water bodies on exposed land surfaces. Most of the pools and streams which appear on ice are ephemeral but some proglacial lakes, such as Lake Untersee (p. 56), may persist and perhaps eventually become contained in a rock basin beneath. Many lakes in the Arctic and Antarctic may have originated in this way (Friddle and Heywood 1980).
Sea ice as a habitat and ecological interface
Authors: Fogg G E
Published: November 2023

The profound effects of sea ice on the climatic and oceanographic environments in which polar organisms live have been outlined in Chapter 1. It is more variable and heterogeneous in structure than land ice and since it is in contact with liquid water and consequently does not reach such low temperatures as does land ice, it provides a variety of niches for active life. Sea ice has a unique ecological role. It interposes a solid interface between two fluid phases—biologically productive seawater and air, unproductive but allowing exceptional mobility to animals able to take advantage of it. It modifies environmental conditions in the sea below and also provides a platform on which air-breathing birds and mammals can live, breed, and base foraging forays into the water. Although its annual cycle of advance and retreat is a recurrent pattern, the distribution and local structure is irregular. Its variations from year to year affect all levels in the marine ecosystem.
Some conclusions
Authors: Fogg G E
Published: November 2023

The quintessential polar habitat, the ice cap, supports no vital activity but does not extinguish life altogether; some microorganisms can lie dormant in it for seemingly indefinite periods. Lack of moisture, not low temperature itself, is the ultimate constraint and wherever liquid water appears, active life becomes possible and is usually to be found. Around the ice cap such situations are transient and shifting, being colonized only by such opportunistic organisms as are already present in dormant form or whose propagules arrive via air, water, or human visitors.
Camouflage, Colour, and Lights
Authors: Herring Peter
Published: November 2023

We have seen in Chapter 8 how the light environment in the ocean is fundamentally different from that on land. Only at the edges of the ocean arc there any real similarities to the small-scale structure and optical complexity present in fields, woods, or streams. It is here that the water is shallow enough, and the light bright enough, for bottom-living plants to flourish as thickets of algae and sea-grass, and for corals to exploit their photosynthetic symbionts in the exuberance of tropical reefs.
A wonderful Variety of Life: Biodiversity of the Deep-sea Fauna
Authors: Herring Peter
Published: November 2023

Life probably arose in the earliest seas some 4 billion years ago (4000 Ma), perhaps close to hydrothermal springs. There is fossil evidence for the existence of prokaryotic (bacteria-like) organisms 500 million years later and mats of cyanobacteria-like organisms or stromatolites were abundant 3 billion years ago (3000 Ma).
The extant species
Authors: Kobel H R , Loumont C , Tinsley R C
Published: November 2023

As a result of recent detailed analysis of live specimens and also of sampling in more remote parts of Africa, the number of Xenopus species has trebled in the last 20 years. Studies of karyotype and DNA-content demonstrate a remarkable series of polyploid species. Based on two different chromosome sets of 10 and 18, they represent ploidy levels of 2:4:8:12. In fact, when compared with other members of the Pipidae, only a single species seems to have remained diploid. Other criteria used to define species are the mate calls, which in almost all cases are species-specific, and experimental hybridization, which reveals genetic incompatibilities (fertilization barriers, viability, sterility, meiotic chromosome pairing).
An overview of the anuran fossil record
Authors: Sanchiz Borja , Rocek Zbynek
Published: November 2023

A general overview of the known anuran fossil record is presented, with an emphasis on diversity and extinct groups. The fossil record is analysed for all anurans at the family level, and palaeontological minimal ages are inferred. Most of the record can be referred to extant families, but a few exceptions remain: the South American Jurassic Vieraella and Notobatrachus, the Asiatic Cretaceous Gobiates and the holarctic palaeobatrachids are especially discussed in this regard. However, the real evolutionary pattern appears to include few examples of lost, extinct diversifications within the order Anura, unless this merely derives from a sampling bias of the known fossil record. Diversity in the past has not proven to be higher than today, and it seems to have been growing very slowly through time.
Systematic implications of lactate dehydrogenase isozyme phenotypes in Neotropical pitvipers {Viperidae: Crotalinae)
Authors: Werman Steven D
Published: November 2023

Lactate dehydrogenase isozyme phenotypes were surveyed from kidney tissues of pitvipers by means of horizontal starch-gel electrophoresis. Individuals of 23 species, representing the general Agkistrodon, Atropoides, Bothriechis, Bothriopsis, Bothrops, Cerrophidion, Crotalus, Lachesis, Porthidium, Sistrurus and Trimeresurus, were examined. Phenotypic variation based on the mobility class of LDHA, the loss of specific isozyme expression and relative isozyme intensity differences were used to evaluate existing systematic and phylogenetic issues.
DNA evolution of South American pitvipers of the genus Bothrops (Reptilia: Serpentes: Viperidae)
Authors: Salomao Maria Da Graçca , Wuster Wolfgang , Thorpe Floger S , Bbbsp Jean-Marc Touzet &
Published: November 2023

The Neotropical pitvipers currently and formerly included in the genus Bothrops comprise a large number ( > 60) of species. The phylogenetic relationships among the taxa included in this group remain incompletely understood. Here, we analyse the relationships among various species of Bothrops (B. alternatus, atrox, caribbaeus, cotiara, insularis, isabelae, jararaca, jararacussu, leucurus, marajoensis and moojeni) and Bothriopsis (B. taeniata) by means of comparative mitochondrial DNA sequencing. Portions of the cytochrome b gene were amplified by means of the polymerase chain reaction (PCR), and sequenced. A 565 bp region of the cytochrome b gene was subjected to phylogenetic analysis, using maximum parsimony, Fitch-Margoliash and maximum likelihood algorithms. All trees confirmed the monophyly of the Bothrops atrox group exclusive of Bothrops jararacussu, the rooting of Bothriopsis taeniata within the genus Bothrops, the basal dichotomy between species with and without a lacunolabial scale, and the sister-species relationships between B. jararaca and B. insularis. On the basis of these results, we synonymize the genus Bothriopsis with Bothrops. Our results are discussed with reference to previous analyses of the phylogeny of Neotropical pitvipers, and points of consensus and remaining problem areas are identified.
Russell ‘s viper in Indonesia: snakebite and systematics
Authors: Belt Paul J , Malhotra Anita , Thorpe Rogers. , Warrell David A , Wuster Wolfgang
Published: November 2023

Russell ‘s viper has a widespread but discontinuous distribution across 10 Asian countries. The presence of the species in southern Indonesia is of particular interest, as these populations are isolated by more than 2000 km from the nearest conspecific populations in Thailand. Formerly divided into five subspecies, the population systematics of this species has recently been revised as a result of a multivariate analysis of scalation and colour pattern characteristics. The analysis reveals two morphologically distinct forms occupying the eastern and western part of the range of the species respectively. While the populations from the Lesser Sunda Islands (Nusa Tenggara Timur) group with the eastern form, they appear to be somewhat divergent from the other populations in Java and continental south-east Asia. In the species as a whole there is clear lack of concordance between morphological and venom variation, but data on venom effects, or indeed on the incidence of bites by this species, is lacking for the Indonesian populations.

In this paper, fresh distributional data from recent expeditions and the results of a retrospective case study of Russell ‘s viper bites (n = 26) from the Lesser Sunda Islands are presented. The magnitude of the public health problem and effect of medical and traditional treatments on outcome are assessed. The case fatality of Russell ‘s viper bites in Indonesia is 38.5%. The mean interval between snake bite and death is 14.5 h, which is considerably shorter than that reported from other Asian populations. Incoagulable blood caused by procoagulant effects of the venom and the ensuing consumption coagulopathy is the most common feature across the entire geographical range.
Toxic phospholipases in snake venom: an introductory review
Authors: Harris John B
Published: November 2023

Many snakes elaborate several phospholipases A2 and some elaborate phospholipase A2 homologues with little or no biological activity. Since each phospholipase A1a homologue is the product of a single gene, the animals clearly expend a great deal of metabolic energy in maintaining the expression of so many similar genes. Perhaps this suggests that there is a selective advantage to the production of such a multiplicity of protein homologues.

Analysis of the structure of the phospholipases A2 isolated from snake venoms suggests that the enzymes of viperid/crotalid snakes and elapid/hydrophid snakes respectively have evolved from different precursors.

The toxic phospholipase A2 components of venom are of great clinical signifi-cance; the long-term neurotoxicity that results from many bites can be fatal and is a therapeutic challenge; myotoxicity is potentially life-threatening and difficult Ito control.
Zeolites
Authors: Newsam John M
Published: November 2023

The properties of zeolites derive directly from the particular characteristics of their crystal structures and the broad field of solid state chemistry provides few other examples where the interplay between local structure and bulk macroscopic properties can be so directly observed. Academic and industrial interest in zeolites continues to grow steadily. This reflects the expanding scope of zeolite synthetic procedures, and further developments in commercial zeolite utilization. In addition, many of the solid state characterization tools that have been developed over the past two decades or so1 arc directly applicable to zeoiite structural problems. The deeper understanding of zeolite chemistry that such techniques promise affords the hope of more direct control of zeolite synthesis, and of developing predictive capabilities for zeolite selection and optimization for particularly desired applications.
Atoms And The Topology Of The Charge Density
Authors: Bader Richard F W
Published: November 2023

It would be a voluntary and unnecessary abandonment of most valuable aid, if an experimentalist, who chooses to consider magnetic power as represented by lines of magnetic force, were to deny himself the use of iron filings. By their employment he may make many conditions of the power, even in complicated cases, visible to the eye at once; may trace the varying direction of the lines of force ;1nd determine the relative polarity; may observe in which direction the power is increasing or diminishing; and in complex systems may determine the neutral points or places where there is neither polarity nor power, even when they occur in the midst of powerful magnets. By their use probable results may be seen at once, and many a valuable suggestion gained for future leading experiments.
‘An exceedingly ingenious thesis’
Authors: Kipnis A Ya , Yavelov B E , Rowlinson J S
Published: November 2023

Van der Waals’s two corrections have a wonderful effect; the simple equa tion (3.2), which describes only the limiting case of an ideal gas (a theoretical rather than a real substance) metamorphoses into an equation that covers the fluid states of matter from a dilute gas to a dense liquid, and accounts also for the existence of a critical point at which the distinction between these phases vanishes. How did he obtain this remarkable result? In his Nobel Lecture in the autumn of 1910, van der Waals recalled that ‘The first incentive to this my life’s work came to me when, after my studies at university, I learned of a treatise by Clausius (1857) on the nature of the motion which we call heat’ [103e, p. 254]. This treatise is, of course, Clausius’s famous paper Ueber die Art der Bewegung, welche wir Wdrme nennen [2].
At the Royal Academy of Sciences
Authors: Kipnis A Ya , Yavelov B E , Rowlinson J S
Published: November 2023

Van der Waals was a member of the Academy for almost forty years. Here he sent all his papers, and here he showed himself to be a leading organizer of science. From the earliest days of his membership he was one of the most conscientious attenders in his Section, that is, the Physical and Mathematical Division (PMD). But after the meeting on 24 December 1881, when he had presented a report on the possible dependence on temperature of the internal pressure of liquids and gases [19], his name vanished for three semesters from the reports of the monthly meetings. For a year and a half a member of the Academy ignored its meetings, without even an apology for absence or explanation of why he would not attend. He ran the risk of expulsion, since a member who failed to attend for two years without a valid reason was expelled automatic ally. After the death of his wife, however, van der Waals had lost all interest in scientific gatherings. It was perhaps with the aim of bringing him back to active life that the Section elected him to be a Vice-President. This election in absentia took place in the spring of 1883 and seems to have achieved its purpose since van der Waals started to attend again in the autumn semester of that year. The next autumn he gave a report [20] on the magneto-optical investigations of his first assistant, Ph. Kaz.
Van der Waals and Russian Science
Authors: Kipnis A Ya , Yavelov B E , Rowlinson J S
Published: November 2023

This chapter serves both as a ‘case history’ of the spread of the ideas of van der Waals to another country, and also to inform Western readers of the contributions of Russian scientists to the development of his ideas in molecular physics and physical chemistry. The first report of van der Waals’s work in Russia came from A.G. Stoletov, one of the few owners of the Dutch original of Continuity. In January 1879 he published a Sketch of the development of our knowledge of gases [1], which contained ‘a new law’, that is, the equation of state of van der Waals. Stoletov wrote that this ‘explains exactly all the complicated phenomena if we ascribe to gas molecules only a definite volume and a definite force of cohesion. Conversely the experimental data on any gas can be fitted to the law of van der Waals, and so we can determine the size of the molecules and the strength of their mutual attraction. Thus the irregularities of gases, their deviations from ‘ideal’ behaviour, have a particular significance; they provide us with the means of solving problems in the world of atoms that are apparently totally inaccessible’ [1, p. 174]. The quotation shows that even in these early days van der Waals was not alone in his ideas and Kamerlingh Onnes was right to note that ‘Stoletov was, of course, among the first to understand van der Waals’ [233].
In retirement
Authors: Kipnis A Ya , Yavelov B E , Rowlinson J S
Published: November 2023

Nevertheless the age of seventy is the age of retirement, the official boundary between work and rest in Dutch academic life. An academician who has reached this limit becomes a rustend lid; he keeps his rights but is relieved of his obligations, in particular, he is no longer required to attend the sessions of his Section, and his place in the Academy is filled at a new election. For university teachers the law requires retirement at the end of the academic year in which a professor or lector becomes seventy. On 21 March 1908 he sent to the City Council of Amsterdam a request that he might retire at the end of his current course of lectures, and expressed his thanks for the enjoyment of the Council’s unfailing confidence [250, p. 278]. Van der Waals accepted that there must be this change in his life but there is no trace of his coming retirement in the last courses of lectures he gave. As in previous years, he was unfailingly in his laboratory by 9 in the morning. Once during this last winter there was an unprecedented snow storm one night, but he still was in his place in the morning to find a very thin class before him. He said, with a chuckle, ‘I appreciate very much the presence of those gentlemen who were not kept away by the weather’ [190, p. 328].