bluuebunny/crossref_metadata_2025 huggingface dataset:
The selection of coloured stimuli by the horse (Equus caballus)
Authors: C.A. Hall  , Cassaday H.J. , Vincent C.J. , Derrington A.M.
Published: June 2019

Colour is an important feature that increases the visibility of objects and may aid recognition of con-specifics. The adaptive significance of the ability to utilize colour cues has been demonstrated in a number of species, in particular in relation to food selection. The evolution of trichromatic colour vision in primates has been associated with the advantages that it provided in the selection of yellow and orange fruits (Mollon, 1989) or tender young red foliage (Dominy and Lucas, 2001) from a background of green. The horse is a generalist herbivore that must both select nutritious plants and avoid toxic ones. Familiarity is an important factor in this selection process (Augneret al., 1998), although it is not clear exactly what features are used to recognise previously ingested and “safe” herbage.

The horse has been shown to possess dichromatic colour vision. There are two types of cone photopigment in the equine retina, with spectral peaks at 429 and 545 nanometres (Macuda, 2000).
Dressage scoring patterns at a selected Pre-Novice event
Authors: Whitaker T. C. , Hill J.
Published: June 2019

The assessment of dressage tests within equine competition is undertaken via a judge (or panel of up to three judges at the higher levels of the sport). Judges assess and award marks for a series of pre-determined movements; such marks are given in line with criteria laid down by relevant governing equestrian organisations. Additionally, judges undergo training and assessment designed to enable them to adhere to the required guidelines as closely as possible. The equestrian sport of eventing is a three phased sport consisting of the completion of a dressage test, speed and endurance test (cross country) and round of show jumps. The speed and endurance phase is considered the most important and influential phase of competition; the sport's governing body, the International Equestrian Federation (FEI), describe it as the ‘major test’ (FEI). Various authors (Duell and Russek-Cohen, 1995; Whitaker et al, 2004; Whitaker and Hill, 2005) have demonstrated that the dressage phase contributes to the largest percentage of penalty points within the overall final penalty score from all the phases of competition.
Multivariate analysis of international level (CCI****) eventing competition
Authors: Whitaker T. C. , Hill J.
Published: June 2019

Eventing is a three phased equestrian sport involving the completion of dressage, speed and endurance phases (cross country course) and show jumping phase. Penalty points are accrued during each phase of competition;. Competitors are ranked within competition on the basis of overall penalty points accrued (lowest points – winning the competition). The relative influence of each phase of the competition is currently being debated by the Federation Equestre Internationale (FEI) and its membership. The reasons for this, amongst other factors, include concerns over equine welfare, financial commitment to infrastructure and accessibility of nations developing within the sport. The essence of eventing, a speed and endurance contest, has been based around the cross country phase; the FEI refers to the phase as ‘the major test’ (FEI 2003) and British Eventing (BE) state ‘‘the relative influence on the whole competition exerted by dressage should be slightly more than that exerted by the show jumping, but considerably less than that exerted by the cross country’’ (BE 2004).
Upregulated mesoaccumbens dopamine transmission alters extinction learning profile of an operant response
Authors: Hemmings A.J. , McBride S.D. , Hale C.E
Published: June 2019

Crib-biting horses were recently shown to exhibit increased activity within the mesoaccumbens dopamine pathway (McBride and Hemmings 2005). Given the multi-factored functionality of the mesoaccumbens system, this alteration in dopamine physiology may have an effect on other aspects of the behavioural repertoire. For instance, in experiments which sought to ascertain the function of the nucleus accumbens in extinction learning, nucleus accumbens dopamine efflux decreased in a linear fashion following unrewarded operant responses, whilst exitotoxic (ibotenic acid) lesions of the nucleus accumbens had the ability to impair response extinction (Ichikawa et al. (2004). Thus, a role for this brain region in extinction learning is certainly implicated. The aim of this study was to determine if facilitated accumbens dopamine transmission affects learning characteristics in the horse. From the aforementioned discussion it was hypothesised that enhanced accumbens dopamine transmission would potentially delay the linear reduction in dopamine release associated with extinction of an operant response. Or, from a functional perspective, cause heightened salience of a conditioned stimulus thereby delaying the onset of extinction learning.
The effects of Reiki on the heart rate of horses
Authors: Hale C.E. , Spibey V.
Published: June 2019

Reiki is an increasingly popular form of complementary therapy. It originated in Japan, and is used to promote relaxation and healing (Rand, 2000). Reiki is a vibrational therapy that is claimed by practioners to be a method of channelling universal life energy (Mansour et al., 1999). This energy is then claimed to balance the biofield and initiate the body's own healing processes (Miles & True, 2003). The therapy involves the flow and transfer of energy, from the practitioner, to the patient. Often described as the “laying on of hands” (Rand, 2000), patients report feelings of warmth, deep relaxation, sleepiness, happiness, increased spiritual awareness, (Rand, 2000) and improved pain control (Olson et al., 2003).

Reiki has become popular as an adjunct to conventional medicine (Miles & True, 2003; Olson & Hanson, 1997), and is increasingly being used alongside traditional palliative care for people with serious illnesses (Miles & True, 2003; Wardell & Engebretson, 2001; Neild-Anderson & Ameling, 2000; Mansour et al., 1999; Bullock, 1997; Olson & Hanson, 1997).
Scientific and methodological issues in quality assurance
Authors: Russell Ian , Grimshaw Jeremy , Wilson Brenda
Published: June 2019

Synopsis

The framework for this chapter stems from the proposal that the basic steps of the quality cycle should be combined with the practical stages of the scientific method to form an extended quality cycle comprising nine steps. The scientific and methodological implications of each step are considered in turn. The discussion of the three steps relating to the development, dissemination and implementation of clinical standards is based on a recent review of rigorous evaluations of clinical guidelines. The discussion of the three steps relating to the comparison of clinical performance with agreed standards is based on the existing principles of medical research. The final step is concerned with the management of change. The chapter ends by applying the steps of the extended quality cycle to the topic of thrombolytic therapy after acute myocardial infarction. The resulting hypothetical quality assurance exercise appears simple and potentially very effective. We conclude that, if quality assurance is pursued with a combination of scientific rigour, imagination and persistence, it has the potential to bring substantial benefits to patients and health professionals.
Clinical audit in hospital
Authors: Heath D. A.
Published: June 2019

Synopsis

Audit within general medicine originated from a review of patient clinical records. The main effect of such activities was to lead to an improvement of documentation and a realisation that audit could be performed amicably. Once case note reviews had been established it was usually necessary to progress to specific topic review. Such audits required more input of doctors' time, and to be performed properly needed the support of committed audit staff and limited support from computer technology.

The primary aim of medical audit is to improve clinical care. Although an important component it is not the primary purpose of audit to save money.
Quality assurance in general practice
Authors: Baker Richard , Samuel Oliver
Published: June 2019

Synopsis

This chapter traces the development of quality assurance in general practice over the last quarter of a century. The practical implementation of quality assurance in British general practice is set against experience in other countries. Examples illustrate how ideas for improving care have already been incorporated into normal practice. We describe some of the methods currently in use and speculate about how systems of professional accreditation might become acceptable. Finally we consider the future role of quality assurance in general practice.
Quality assurance in the blood transfusion services
Authors: Cash John D.
Published: June 2019

Synopsis

Blood transfusion services, in almost all parts of the developed world, are subject to the same rigours of quality standards as those applied to the rest of the pharmaceutical industry. These standards are established and monitored by governments but are greatly enhanced by staff involvement and commitment. More recent developments, which in some respects are unique to blood transfusion services, have been the commitment of many blood transfusion services to engage in an audit process which seeks to define better the most appropriate uses of blood and blood products.
Quality assurance in histopathology
Authors: Robertson A. J. , Beck J. Swanson
Published: June 2019

There is widespread interest in development of approaches to monitoring the quality of the diagnostic service provided by pathology departments. Novel approaches are being developed for analysis of performance, while there is active interest in the selection of diagnostic categories that can be reliably applied in service laboratories. Initial progress has been slow but organisational problems and professional inertia have been largely overcome. The scene is now set for continuing critical appraisal which must lead to improvements in clinical care.
Quality assurance in biomedical and health services research
Authors: Moir A. T. Boyd , Bouchier Ian A. D.
Published: June 2019

Synopsis

In this paper we deal with those methods which are used, or which may be used, to ensure that research in the biomedical and health services field is of a satisfactory standard. We discuss not only what is undertaken to ensure that the quality of the applications which are funded is of the best, but also those activities which may be pursued in an endeavour to stimulate a healthy quantity of high-quality applications for research. This latter point is an issue relating primarily to health services research. We cover the topic of quality assurance of biomedical and health services research from an experience which is derived mainly, but not solely, from involvement with Scottish funding agencies. Consideration is given to the allocation of budgets for research in medicine and the impact that this has on the quality of biomedical and health services research.
The Shetland environment, the establishment of the Sullom Voe Environmental Advisory Group, development of Shetland Oil Terminal Environmental Advisory Group and its monitoring strategy
Authors: Dunnet G. M.
Published: June 2019

The Shetland Islands lie between latitudes of approximately 60° and 61° North, over 100 miles north of the Scottish mainland. They are influenced by the North Atlantic Drift so that the climatic conditions are much less severe than for other land masses, for example in Southern Greenland where the mean temperature for five months of the year is below freezing. The environment in all its considerable heterogeneity is well described in The Natural Environment of Shetland (Goodier 1974) and in The Natural History of Shetland (Berry & Johnston 1980). Briefly the islands lie on the western oceanic fringe of Europe, have approximately 1450 kilometres of coastline and an area of 1468 square kilometres. The geology is varied and geomorphologically the islands constitute a drowned range of glaciated hills situated on the continental shelf. The coast consists of extensive areas of cliffs and voes with relatively few beaches. In general, the ‘outer’ coasts, especially on the west, are exposed high energy environments. In contrast, the inner coasts, often voes, are deep sheltered inlets. The land itself tends to be hilly and, where it has not been stripped for agricultural use, is blanketed with peat, with the main vegetation heather (Calluna vulgaris) and cotton sedge (Eriophorum angustifolium). Approximately 10% of the land is covered by rushy vegetation and there is very little relict scrub though there are one or two planted woodland plots. The original scrub was largely eradicated by man who arrived in Shetland from Iberia about 3500 BC. Colonisers from Scandinavia arrived in the eighth century and have had a lasting influence on the culture of the islands. In 1971 the human population was about 17327 and in 1989 was 23 214 (SIC 1992).
The monitoring of breeding seabirds and eiders
Authors: Dunnet G. M. , Heubeck M.
Published: June 2019

Twenty-one species of seabirds breed regularly in Shetland, some of them in huge, spectacular, multi-species colonies on cliffs. The Sullom Voe Environmental Advisory Group Environmental Impact Statement (SVEAG 1976) provides a table showing the relative importance of seabird species in terms of Scotland and the British Isles. We have updated these data in the light of the Seabird Colony Register (Lloyd et al. 1991) and present data for seven species, vulnerable to oil pollution, in Table 1. It is clear that these populations are of national importance and indeed several are internationally important. Separately, an estimate was provided by SVEAG of the numbers of sea ducks and divers wintering in Shetland waters and updated estimates are given by Suddaby (1992) (Table 2). Chief among these is the eider duck (Somateria mollissima) which is apparently resident in Shetland throughout the year (Heubeck 1993a). In its Eighth Report, on Oil Pollution at Sea, the Royal Commission on Environmental Pollution (1981) recognised the vulnerability of seabirds to oil pollution and this was clearly a matter of concern in Shetland and elsewhere when the flow of enormous quantities of crude oil into Sullom Voe via undersea pipelines and out of Sullom Voe by large tankers became a reality. The risk to seabirds of oil pollution is well documented (Bourne 1968; RSPB 1979). Dunnet (1974, 1980, 1982, 1987) has reviewed the situation in relation to the North Sea oil industry.
Rocky shores monitoring programme
Authors: Moore Jon , Taylor Peter , Hiscock Keith
Published: June 2019

Synopsis

Rocky shores in Sullom Voe were first surveyed in 1976 and, apart from a break of two years (1982–83), have been surveyed annually since. The aim of the surveys is to monitor the health of the rocky shore communities by identifying any major changes in the abundance of the fauna and flora and distinguishing anthropogenic effects from natural fluctuations. The 23 primary sites are spread around Sullom Voe, from Mavis Grind, at the head, to Mioness, just outside the entrance. A belt transect method is employed, and categorical abundances of conspicuous species on a checklist are recorded. Graphical analysis of the data for selected species and sites is presented to illustrate the most important changes that have been observed.

The rocky shore communities in Sullom Voe are dynamically stable, except where physical disturbance has not allowed them to reach a state of long-term stability. The effects of, and the recovery from, the 1979 Esso Bernicia oil spill and its clean-up are described. While recovery of communities was rapid on shores where no clean-up was attempted, the communities on shores which were mechanically cleaned were showing continued effects in 1993. The deterioration of dogwhelk populations affected by the antifouling paint additive tributyltin (TBT) has been followed in recent years. Dogwhelk populations close to the terminal jetties are very small and are dominated by adults. Natural fluctuations in abundances of barnacles, dogwhelks, limpets, fucoid algae and littorinid gastropods over the period 1976 to 1992 are also described.
Secondary metabolites
Authors: Waterman Peter G.
Published: June 2019

Synopsis

All plants expend energy and nutrients in the production of secondary metabolites. Ecosystem-level studies on the production of metabolites in African rain forests are reviewed and factors influencing the production and distribution of phenolic compounds discussed. These compounds appear to influence feeding behaviour in primate herbivores and may also be important in mediating the rate of leaf litter decomposition and nutrient recycling. Many metabolites are biologically active and some have proved to have medicinal value: research on some plant families that occur widely in West African forests and which have proved to be particularly rich sources of new metabolites is reviewed.
Mammals of the Guinea–Congo rain forest
Authors: Happold D. C. D.
Published: June 2019

Synopsis

The species composition, and the number of species of mammals, in the Guinea–Congo rain forests varies with locality. The highest species richness (up to 130 species) is found in parts of the West Central and East Central rain forest regions, and the lowest richness occurs in the Western Region and on the periphery of the rain forest zone. Rodents and bats contribute the greatest number of species (about 25% each), with lesser numbers of primates, duikers, and small insectivores; the relative numbers within each order is similar in all localities regardless of the composition and total numbers of species. The geographical distribution of each species is due to the alternating periods of forest fragmentation and expansion in the past, and the species-specific response to these environmental changes. There are about equal numbers of arboreal (30%), terrestrial (35%) and aerial (27%) species, each species within these categories having very specific habitat requirements within the forest. Most rain forest mammals are either frugivores (36%) or insectivores (37%): monkeys are mainly arboreal frugivores and folivores, and most prosimians are arboreal insectivores; forest duikers are terrestrial frugivores, and terrestrial rodents are frugivores or omnivores. Leaves, in spite of their abundance, are rarely eaten because of their low nutritive value and the difficulties of digesting them and consequently folivores (9%) are uncommon. Insects form the principal food for insect-bats and shrews. Mammals exhibit well-defined food partitioning in relation to food selection and body size, and therefore competition for food is probably minimal except during the dry season. Reproduction is more or less continuous in rodents and artiodactyis (with peaks of births at selected seasons); in contrast, monkeys and bats have fairly precise periods when births occur, which vary according to the species. The timing of reproductive events is regulated by the rainfall regime, availabiiity of food, and phyiogenetic characteristics such as the length of gestation and body size. Mammals interact with other rainforest organisms, principally as primary and secondary consumers, pollinators, and dispersers of fruits and seeds. Most species of rain forest mammals are solitary, but a few live in monospecific groups or in polyspecific groups. Forest disturbance in recent years (especially forest clearance and hunting) has had very detrimental effects on the geographical distribution and numbers of individuals of all species of forest mammals.
Ectomycorrhizal fungi of the Guinea–Congo Region
Authors: Buyck Bart , Thoen Daniel , Watling Roy
Published: June 2019

Synopsis

The occurrence of ectomycorrhizal fungi in West African rain forest systems is demonstrated and linked to the presence of a range of caesalpinoid legumes and to members of the genusUapaca. The vast array of boletes, members of the Russulaceae and Amanitaceae, and chanterelles is described. The virtual absence of ectomycorrhizal Cortinariaceae is emphasised. After an overview three separate yet interlinked studies are described: a survey of ectomycorrhizal fungi throughout the region (Thoen): ectomycorrhizal fungi of a single rain forest community (Watling) and the significance and relationships of the genusRussulain the Guinea–Congo Region (Buyck). Some comparisons are made with other rain forest areas of the world.
Saprotrophic fungi of the Guinea–Congo Region
Authors: Laessøe T. , Ryvarden L. , Watling Roy , Whalley A. J. S.
Published: June 2019

Synopsis

A window onto the vast array of saprotrophic fungi found in West Central Africa with particular reference to the Cameroon attempted in this paper. After an overview (Watling) three diverse groups are taken as examples of this array: xylariaceous fungi (Laessøe, Whalley & Watling); polypores (Ryvarden & Watling) and lepiotoid fungi (Watling). Some comparisons are made with other tropical forests. This approach contrasts a lignicolous group in the ascomycetes with one in the basidiomycetes and contrasts terricolous lepiotoid agarics with polyporaceous terricolous and lignicolous fungi.
Growth control of normal and malignant breast epithelium
Authors: Lippman Marc E. , Dickson Robert B.
Published: June 2019

Synopsis

We review information highlighting the multiple roles of both steroidal (primarily oestrogen) and polypeptide regulators of mammary epithelial cell growth, emphasising the work of our laboratory. Effects of both classes of hormones are complex and involve multiple interactions with non-tumour, host tissue. Oestrogen may induce growth regulatory polypeptide growth factors and interact with them in hormone dependent breast cancer. Progression of hormone-dependent breast cancer to hormone independence may involve multiple genetic mechanisms of oncogene activation, loss of the oestrogen receptor, or loss of hormone responsivity of other gene products. Initial carcinogenesis and progression of mammary epithelium to cancer probably also requires both proliferative stimuli (oestrogen, polypeptide growth factors) and genetic damage, leading to qualitatively different hormonal responses (hormone responsive cancer). Future therapies should be designed to block hormonal stimulation better and to interfere with necessary activated or induced components of malignant progression such as oncogenes or polypeptide growth factors receptor systems.
Effects of oestrogen on human breast cancer cells in culture
Authors: Darbre Philippa D. , Daly Roger J.
Published: June 2019

Synopsis

Oestrogen regulates the growth of human breast cancer cell lines ZR-75–1, T-47-D and MCF-7 (KO and McGrath). Basal cell growth can be reduced (T-47-D) or eliminated (ZR-75–1) by prior growth in the absence of steroid and phenol red for three weeks, demonstrating that oestrogens can have long-lasting effects on cells in culture (termed “steroid memory”). Effects of oestradiol on different cell biological parameters are described and interaction with other steroids and serum growth factors is discussed. Antioestrogen action in these cell lines is affected by at least five parameters: (1) presence of phenol red, (2) time in culture, (3) cell density, (4) antioestrogen concentration, (5) steroid memory.

Anin vitromodel for loss of oestrogen sensitivity in breast cancer is presented. Both dependent (ZR-75–1) and responsive (T-47-D) cells lose oestrogen sensitivity when deprived of steroid in the long term but show a gradual increase in growth. For ZR-75–1 cells, the effects appear to be clonal but occur at a high frequency (about 1 in 1,000 cells). Parallel alterations in sensitivity to other steroids, antioestrogens and serum growth factors are shown. Molecular markers of this action are described and the results compared with the well-established model for loss of androgen/glucocorticoid sensitivity in SI 15 cells.
The regulation of oestrogen biosynthesis in human adipose tissue
Authors: Simpson E. R. , Mendelson C. R.
Published: June 2019

Synopsis

The enzyme complex responsible for the conversion of androgens to oestrogens is called aromatase. This enzyme is expressed in a number of tissue sites, including granulosa cells, placenta, hypothalamus and adipose. Oestrogen formation in adipose tissue has been implicated in the aetiology of endometrial and breast cancer. Aromatase comprises two components: a member of the cytochrome P-450 gene family known as aromatase cytochrome P-450, and a flavoprotein, NADPH-cytochrome P-450 reductase. We have recently obtained a full-length cDNA insert encoding human aromatase cytochrome P-450 and have expressed it in COSI monkey kidney tumour cells. The resulting transcript encodes a protein which is capable of converting androstenedione, testosterone and 16α-hydroxyandrostenedione to the corresponding oestrogens. Furthermore, characterisation of the aromatase cytochrome P-450 gene indicates that in humans there is only one such gene, which spans about 30kb and has at least nine exons. From these results we conclude that there is only one aromatase enzyme in humans. Study of the expression of this enzyme in human adipose stromal cells indicates that it is subject to regulation by a number of factors including cAMP, phorbol esters, and the growth factors, EGF, TGF-α, TGF-β, TNF and 1Lβ. Since several of these growth factors are produced by breast cancer cells in response to oestrogens, the possibility exists for paracrine and autocrine feedback loops within the breast, in which the growth of a tumour is regulated by oestrogen produced locally in the adipose cells of the surrounding tissue, and this in turn is regulated by the growth factors produced by the tumour as a result of oestrogen action.
Biosynthesis of active oestrogens in the breast
Authors: Vermeulen A. , Deslypere J. P.
Published: June 2019

Synopsis

It is generally accepted that sex hormones play a role in the development of mammary cancer and it is a reasonable assumption that tissue concentration of oestrogens and their androgen precursors, as well as the activity of oestrogen synthetising or metabolising enzymes, may be valuable parameters of hormone dependency. Except for the sulphate conjugates and for testosterone, androgen and oestrogen levels are higher in mammary tissue (ng/g) than in plasma (ng/ml) and as distinct from plasma, tissue oestradiol (the active oestrogen) levels are higher than oestrone levels. Moreover, oestradiol levels are higher in oestrogen-receptor-positive tissues.

Sex hormone levels in mammary tissue find their origin in uptake from plasma and in local synthesis. It is unlikely that local aromatase activity accounts for a large fraction of tissue oestrogens but sulphatase activity may be an important determinant of tissue oestrogen concentration. The major precursors of tissue oestrogens are androstenedione and oestrone sulphate respectively, yielding oestrone which is transformed by the 17β-hydroxysteroid dehydrogenase to oestradiol. However, the reverse reaction, conversion of E2 into E1, is much more active and is inversely correlated to dehydroepiandrosterone (sulphate) concentration, which inhibits non-competitively the conversion of E2 into E1. This E2DH activity is higher in E2R positive tumours, suggesting that E2DH is a good marker of hormone dependency. As to prognostic factors, a follow-up study concerning sixty-two postmenopausal women, with a follow up of at least four years, revealed that in the recurrence group (n = 17 ), besides E2R and PgR concentrations, all hormone concentrations as well as E2DH activity were also lower than in the disease-free group.
Current controversies in the role of antioestrogens in the treatment of carcinoma of the breast
Authors: Baum M. , Fraser S. C. A. , Colletta A. A. , Ebbs S. R.
Published: June 2019

Synopsis

The development of the triphenylethylene derivatives has been a major advance in the treatment of breast carcinoma, due to their low toxicity. Currently there is controversy not only about their mode of action but in three main areas of clinical practice: (A) adjuvant therapy in premenopausal and oestrogen receptor-negative cases; (B) primary therapy in the elderly; (C) the prevention of breast cancer.

The United States' National Institute of Health consensus of 1985 that adjuvant tamoxifen be confined to postmenopausal women with positive nodes and ER positive tumours has been refuted by randomised clinical trials. The evidence that ER negative tumours also respond to tamoxifen has added to laboratory evidence that tamoxifen acts other than purely by oestrogen antagonism at the ER.

The use of tamoxifen as sole treatment in primary breast cancer in the elderly is being evaluated in randomised clinical trials. Two that have been reported so far have flaws which make their contradictory conclusions difficult to assess.

Recent results from the CRC trial suggest that tamoxifen has more benefit than simply preventing cancer deaths and clarification of the effects of triphenylethylenes on bone metabolism and the cardiovascular system may strengthen the case for a trial of prophylactic tamoxifen in those at risk of developing breast carcinoma.
Novel antioestrogens
Authors: Wakeling A. E. , Bowler J.
Published: June 2019

Synopsis

Recently described 7α-alkylamide analogues of oestradiol, exemplified by ICI 164,384, have the pharmacological characteristics of pure antioestrogens. ICI 164,384 is completely free of oestrogenic activity in rodents and blocks the trophic actions of exogenous and endogenous oestradiol and of partial agonist antiooestrogens like tamoxifen. In addition, ICI 164,384 is peripherally selective, producing complete involution of the uterus without affecting LH secretion in intact female rats.

In MCF-7 oestrogen-responsive, human breast cancer cells ICI 164,384 is a more potent and effective inhibitor of cell growth than tamoxifen. This difference in efficacy is reflected by a greater reduction in the proportion of cells continuing DNA synthesis in ICI 164,384-treated cultures than in tamoxifen-treated cells. This observation implies that a pure antioestrogen may provide more effective therapy of breast cancer but this will have to be demonstrated in clinical studies.
The ecology and conservation of sublittoral hard substratum ecosystems in Scotland
Authors: Hiscock Keith
Published: June 2019

Synopsis

The species assemblages which occur on sublittoral hard substrata in Scotland reflect the following major environmental features: physiographic nature of the coastline, salinity, wave exposure, strength of tidal streams and depth modified by factors such as geographical location, geology, local topographical features, artificial substrata, scour, grazing, disturbance and pollution. Sublittoral hard substratum habitats and communities are affected by many of mans' activities including fishing and harvesting, damage by fishing equipment, organic input, nutrient input, chemical inputs, harbours and moorings, and construction work. Energy generation through wave and tidal power are potential threats. Some of mans' activities also create habitats of scientific interest. Conservation of sublittoral hard substratum habitats and communities requires: description of the character and distribution of habitats, communities and species; evaluation of survey information through application of nature conservation criteria; identification of areas/sites of nature conservation importance; establishment of appropriate consultative and statutory frameworks; obtaining information on biology of species, dynamics/longevity of natural communities and species, and mechanisms ‘driving’ communities; evaluation of damage and recovery; evaluation of effects of diffuse pollution; informing, consulting and educating.
The benthos of soft sublittoral habitats
Authors: Pearson T. H.
Published: June 2019

Synopsis

A brief outline of the characteristics and habitat of marine sedimentary benthos is given together with a consideration of the factors influencing the structure and distribution of benthic communities and the role of larval strategies in influencing recruitment to such communities. The bearing these ecological factors have for the conservation of such communities in Scottish waters is discussed in the context of current and potential threats to their present stability and distributions. It is suggested that the rich communities of the fjordic and shelf areas of the western coast and island groups merit the greatest current concern for conservation, in the face of increasing pressures from a range of developmental actions.
Evolutionary Trends of Zooidal Shape
Authors: McKinney Frank K.
Published: June 2019

The individual functioning units (zooids) in stenolaemate bryozoan colonies include skeletal portions called zooecia (singular, zooecium). Within a zooecium there may be basal diaphragms that make the occupied portion (living chamber) shorter than the full length of the zooecium, and there may be various skeletal parts that project into and modify the shape of the living chamber. The entire zooecium constitutes a record of zooidal ontogeny and of the geometrical relationships between neighboring zooecia or between zooecia and the surrounding colonial tissues. Therefore, evolutionary changes in zooecial shape reflect changes in all stages of zooidal ontogeny and in relationships between zooids and their surrounding intracolonial environment. In addition, evolutionary changes in zooidal size have affected zooecial shape in some stenolaemate groups.
Coloniality and the Origin of Post-Triassic Tubular Bryozoans
Authors: Boardman Richard S.
Published: June 2019

Bryozoa are the only phylum in which all known species form colonies. A colony consists of one or more kinds of physically connected zooids and supporting parts, all assumed to be genetically uniform. The physically connected zooids of a colony generally grow from the sexually produced first zooid, the ancestrula (Fig. 1). Growth in asexually produced colonies is similar, but originates from the ancestrula of a parent colony.
Biostratigraphic and Paleoenvironmental Relations: A Late Silurian Example
Authors: Amsden Thomas W.
Published: June 2019

Brachiopods have been successfully used for many years to provide local, regional, and worldwide biostratigraphic control. Their value as phylogenetic time-markers is somewhat impaired by the fact that as sessile filter feeders they are particularly susceptible to the impress of varying local environmental conditions. The situation is especially troublesome where precise, finely tuned biostratigraphic zonation is attempted, as it becomes difficult to separate out the effects of time (phylogeny) from the effects of paleoenvironmental variations. Paleoenvironmental interpretations involve many uncertainties, as they are based on indirect evidence, a problem compounded by differences of opinion concerning the data used to provide the basic underpinning.
The Lophophorate Condition
Authors: Valentine James W.
Published: June 2019

Most major topics that bear on the lophophorate condition have been ably treated in preceding contributions for either the Bryozoa or Brachiopoda. Accordingly I shall attempt a comparative approach, first characterizing the lophophorates as a whole and then contrasting the groups with an eye towards the evolutionary implications of resemblances and differences. To set a practical target I shall attempt contrasts between the feeding systems, because they seem to be particularly important to the present habits, habitats and distribution patterns of these groups. From this approach, questions naturally arise as to the evolutionary history of the lophophorates and in particular of extinct types of Brachiopoda for which modern analogues are unknown; these problems form potential research areas of special interest. To conserve space I have tried where possible to cite only more recent and/or general works that themselves contain ample references. I have assumed that by this point in the volume the reader will be acquainted with the gross morphology of bryozoans and brachiopods and with the major descriptive terms applied thereto. Because phoronids are not specifically covered in other contributions, I have included a wider range of phoronid references including some historically important works.
Biology of Planktonic Foraminifera
Authors: Bé Allan W.H.
Published: June 2019

The history of investigations of planktonic foraminifera leading to their current, wide applications in biostratigraphic correlation of Mesozoic and Cenozoic marine sediments can be traced to the discovery by Owen (1867) of the floating habit of certain foraminifera, later confirmed by Brady (1884), and the recognition by Murray and Renard (1891) that their shells constitute a major portion of deep-sea sediments over large regions of the seafloor. The utilitarian value of planktonic foraminifera in paleoecological analysis is also widely accepted today. Fortunately for students of paleoecology, many species of planktonic foraminifera are still extant and live in large numbers in all oceanic regions. Their areal, vertical and seasonal occurrences have been resolved to such a degree that a global synthesis of their distribution patterns is now available (e.g. Bradshaw, 1959; Belyaeva, 1964; Be and Tolderlund, 1971).
Cenozoic Benthic Foraminifera Case Histories of Paleoceanographic and Sea-Level Changes
Authors: Miller Kenneth G.
Published: June 2019

Since the inception of their use in commercial micropaleontology, benthic foraminifera have proven to be eminently useful in the solution of geological problems. The utilitarian credentials of benthic foraminifera in estimating paleodepths from marsh through neritic environments with a reasonable degree of accuracy and to indicate approximate ages (viz. subdivision of series/epochs) have been established in both commercial and academic applications. Benthic foraminifera are generally more resistant to dissolution than planktonic foraminifera, and have wide distributions; many taxa have restricted stratlgraphic ranges, making them suitable for correlation and paleo-environmental studies. Yet, three problems have tended to limit the utility of benthic foraminifera: 1) there is a lack of uniformity in taxonomy (Boltovskoy, 1980; Douglas & Woodruff, 1982); 2) attempts to erect zonal schemes using benthic foraminifera have resulted in boundaries which are later proven to be diachronous relative to planktonic zonatlons (e.g. the California provincial stages, Poore, 1976); and 3) attempts to interpret paleodepths from deep-sea benthic foraminifera have produced widely-varying results. One could perhaps conclude, as Boltovskoy (1965a) did over a decade ago, that these problems indicate “…the near future of this science is rather bleak.”
A Survey of Mammalian Origins
Authors: Jenkins Farish A.
Published: June 2019

The origin of mammals, often treated as a discrete but obscure event that took place sometime between the Late Triassic and Early Jurassic, can also be viewed as the product of many transitions - from the early synapsid radiations during the Pennsylvanian and Early Permian through the emergence of placentals and marsupials in the Cretaceous (see Hopson, 1969). A fundamental dichotomy appeared early in the evolution of amniotes; sauropsids (represented today by living reptiles and birds) constituted one lineage, synapsids (which includes the mammal-like reptiles- pelycosaurs and therapsids- and their mammalian descendants) the other. Thus, mammalian ancestry may be traced to pelycosaurs that first appear in the fossil record as part of the earliest known reptilian fauna (Carroll, 1982). And mammalian bony and dental structures continued to undergo substantial modification throughout the Mesozoic, long after the appearance of forms technically classified as Mammalia. Given these phylogenetic changes, the suggestion that there occurred a point when mammals “originated” seems simplistic. Yet the major evolutionary stages may still be evaluated with the purpose of identifying the inception of features and functions basic to the radiation of modern mammals. Accordingly, this survey summarizes our current understanding of the evolution of mammals with full acknowledgment that an account of mammalian origins has neither a definitive beginning nor a climactic end.
Evolution and Radiation of Mammals in the Eocene, and the Diversification of Modern Orders
Authors: Rose Kenneth D.
Published: June 2019

The Eocene was an especially interesting and important time in the history of mammals. Whereas the Paleocene witnessed the rise of mammals from their previously subordinate position among terrestrial vertebrates, it was during the Eocene that the second major radiation of eutherian mammals took place. Many of the modern orders diversified and achieved dominance on land, and mammals even began to invade the seas and take to the air. By the late Eocene, this explosive radiation had produced the greatest ordinal diversity of mammals known at any time in their history (Lillegraven, 1972). If we could travel back to the Paleocene, we would see few familiar mammals; most belonged to archaic groups that long ago became extinct. But a visitor to the Eocene (given wide latitude in space and time, of course) might recognize many of the denizens of Eocene forests and floodplains—bats, prosimian primates, squirrel-like rodents, rabbits, moles, armadillos, and miniature hoofed animals resembling mouse deer. Along the shore, our hypothetical Eocene naturalist might spot a whale or a primitive sea cow. A closer look would reveal that these animals differed in many ways from living forms, of course, but the resemblances are real and, in some cases, striking. In fact, at least 10 orders of mammals alive today appeared in the fossil record for the first time, or experienced major radiations of modern groups, in the Eocene. Not all Eocene mammals belonged to modern orders, however. There was still a considerable proportion of archaic mammals, many representing lines that had begun in the Paleocene or, in some instances, before. And some of them were highly successful too.
Neogene Faunas of North America
Authors: Webb S. David
Published: June 2019

The second half of the Age of Mammals yields many stories worth telling. The one that I find grandest and most central, however is the “Savanna Story.” While featuring it as the principle theme, I hope to weave in the following secondary subjects:

1) the adaptive radiation of four representative groups, namely hypsodont horses, camels, elephants and cricetid rodents;

2) intercontinental dispersal patterns across Beringia and between the American continents;

3) and faunal turnover patterns.
Primate Evolution
Authors: Gingerich Philip D.
Published: June 2019

The mammalian order Primates includes living tarsiers, lemurs, monkeys, apes and humans. The name Primates itself, derived from Latin primus, first or foremost, betrays a characteristically immodest self-appraisal of our place in nature! When proposed by Linnaeus, in the definitive 1758 edition of his Systema Naturae, nature's center stage was indeed defined as that on which we play. Now, knowing that we are but one of 200 or so living primate species, knowing that primates are but one of 18 or so living mammalian orders, nature's stage appears much grander – claiming the center is clearly more difficult. Central or not, primates we are – human interest in human origins being what it is, primates will always hold a special fascination.
Human Evolution
Authors: Badgley Catherine
Published: June 2019

The evolutionary history of humans is well understood in outline, compared to that of many other groups of mammals. But human evolution remains enigmatic in its details, and these are compelling both scientifically and personally because they relate to the biological uniqueness of humans. Humans are placed in the primate family Hominidae, which, in traditional classifications, contains a single living species, Homo sapiens. The closest living relatives of humans are great apes: the chimpanzees Pan paniscus and Pan troglodytes, the gorilla Gorilla gorilla, and the orangutan Pongo pygmaeus. These apes have traditionally been placed in the family Pongidae as the sister group of Hominidae. Living Hominidae and Pongidae, together with Hylobatidae (gibbons) comprise the modern representatives of the primate suborder Hominoidea.
Plant Taphonomy in Areas of Explosive Volcanism
Authors: Fritz William J.
Published: June 2019

Coarse-grained volcaniclastic sediments are a common part of the non-marine geologic record along most continental margins. Many of these volcanic sediment units contain well-preserved assemblages of fossil plants. Because much of the work on depositional environments, dating, correlations and paleoenvironments has been derived from studies of plants, it is important to understand the processes that incorporate the plants into the volcaniclastic sediments. In this paper I plan to concentrate on processes that bury and preserve trees, logs and stumps.
Selected Aspects of Plant Taphonomic Processes in Coastal Deltaic Regimes
Authors: Gastaldo Robert A.
Published: June 2019

Ancient coastal physiographic provinces have been sites of detrital plant accumulations since the advent of terrestrial vegetation in the Silurian. These lowlands contain remnants of vegetation from a diversity of ecological habitats in a variety of preservational modes and depositional environments. Deltaic regimes within these coastal systems have acted as principal locales for the preservation of in situ (autochthonous) and transported (hypoautochthonous/allochthonous) community elements. A vast majority of our understanding concerning plant diversity and community structure has been centered in the refugia of lowland deltas because of the propensity of these terrigenous sites to become part of the stratigraphic record either by autocyclic or allocyclic mechanisms. Deltaic systems have played a major role in the accumulation of hydrocarbons either as subaqueous (topogenous) and subaerial/aerial (ombrogenous) peats, to be subsequently metamorphosed to coal (McCabe, 1985), or precurssors to natural gas and petroleum (Durand et al., 1986). In certain instances, these peats have been subjected to permineralization and provide the scientific community with an insight into the original standing community biomass (Phillips et al. 1985). Where peats have been coalified, palynomorphs recovered from coal macerations provide information on trends in regional vegetation. Additionally, depending on the relative rates of clastic vs. organic sedimentation in these environments, deltas have acted as repositories for coalified compression and authigenically cemented megafloral and microfloral assemblages (taphocoenoses).
The Early Evolution of Land Plants
Authors: Knoll A. H. , Grant S. W. F. , Tsao J. W.
Published: June 2019

Vascular plants are the most conspicuous organisms on Earth, accounting for some 97 % of our planet's standing biomass. The nearly 300,000 extant vascular plant species exhibit tremendous morphological and ecological diversity. Along with the 20,000 or more species of bryophytes, algae, lichens, and cyanobacteria that also live on land, they fuel a complex terrestrial ecosystem containing animals, fungi, protozoans, and bacteria. The richness of terrestrial life has evolved during the last 10 % of Earth history; there is no evidence for non-microbial land plants or animals in rocks older than the mid-Ordovician.