Abstract Deriving glacier outlines from satellite data has become increasingly popular in the past decade. In particular when glacier outlines are used as a base for change assessment, it is important to know how accurate they are. Calculating the accuracy correctly is challenging, as appropriate reference data (e.g. from higher-resolution sensors) are seldom available. Moreover, after the required manual correction of the raw outlines (e.g. for debris cover), such a comparison would only reveal the accuracy of the analyst rather than of the algorithm applied. Here we compare outlines for clean and debris-covered glaciers, as derived from single and multiple digitizing by different or the same analysts on very high- (1 m) and medium-resolution (30 m) remote-sensing data, against each other and to glacier outlines derived from automated classification of Landsat Thematic Mapper data. Results show a high variability in the interpretation of debris-covered glacier parts, largely independent of the spatial resolution (area differences were up to 30%), and an overall good agreement for clean ice with sufficient contrast to the surrounding terrain (differences ∼5%). The differences of the automatically derived outlines from a reference value are as small as the standard deviation of the manual digitizations from several analysts. Based on these results, we conclude that automated mapping of clean ice is preferable to manual digitization and recommend using the latter method only for required corrections of incorrectly mapped glacier parts (e.g. debris cover, shadow).
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Because research on nematode involvement in trophic interactions, foodweb structure, and biodiversity is constrained by lack of an overview of nematode feeding habits, this outline presents a consensus of current thought on nematode feeding habits. The source of food is fundamental to trophic interactions and provides the basis for our definitions of the essential feeding types: 1) plant feeder, 2) hyphal feeder, 3) bacterial feeder, 4) substrate ingester, 5) predator of animals, 6) unicellular eucaryote feeder, 7) dispersal or infective stage of parasites, and 8) omnivore. Lists of families and genera with their presumed feeding types are given. Major gaps in knowledge of feeding in the smaller tylenchids and many dorylaims are noted.
Anthony Giddens has been in the forefront of developments in social theory for the past decade. In The Constitution of Society he outlines the distinctive position he has evolved during that period and offers a full statement of a major new perspective in social thought, a synthesis and elaboration of ideas touched on in previous works but described here for the first time in an integrated and comprehensive form. A particular feature is Giddens' concern to connect abstract problems of theory to an interpretation of the nature of empirical method in the social sciences. In presenting his own ideas, Giddens mounts a critical attack on some of the more orthodox sociological views. The Constitution of Society is an invaluable reference book for all those concerned with the basic issues in contemporary social theory.
Outline of a Theory of Practice is recognized as a major theoretical text on the foundations of anthropology and sociology. Pierre Bourdieu, a distinguished French anthropologist, develops a theory of practice which is simultaneously a critique of the methods and postures of social science and a general account of how human action should be understood. With his central concept of the habitus, the principle which negotiates between objective structures and practices, Bourdieu is able to transcend the dichotomies which have shaped theoretical thinking about the social world. The author draws on his fieldwork in Kabylia (Algeria) to illustrate his theoretical propositions. With detailed study of matrimonial strategies and the role of rite and myth, he analyses the dialectical process of the 'incorporation of structures' and the objectification of habitus, whereby social formations tend to reproduce themselves. A rigorous consistent materialist approach lays the foundations for a theory of symbolic capital and, through analysis of the different modes of domination, a theory of symbolic power.
This paper provides an updated classification of the Kingdom Fungi (including fossil fungi) and fungus-like taxa. Five-hundred and twenty-three (535) notes are provided for newly introduced taxa and for changes that have been made since the previous outline. In the discussion, the latest taxonomic changes in Basidiomycota are provided and the classification of Mycosphaerellales are broadly discussed. Genera listed in Mycosphaerellaceae have been confirmed by DNA sequence analyses, while doubtful genera (DNA sequences being unavailable but traditionally accommodated in Mycosphaerellaceae) are listed in the discussion. Problematic genera in Glomeromycota are also discussed based on phylogenetic results.
The approach described in this paper represents a substantive departure from the conventional quantitative techniques of system analysis. It has three main distinguishing features: 1) use of so-called ``linguistic'' variables in place of or in addition to numerical variables; 2) characterization of simple relations between variables by fuzzy conditional statements; and 3) characterization of complex relations by fuzzy algorithms. A linguistic variable is defined as a variable whose values are sentences in a natural or artificial language. Thus, if tall, not tall, very tall, very very tall, etc. are values of height, then height is a linguistic variable. Fuzzy conditional statements are expressions of the form IF A THEN B, where A and B have fuzzy meaning, e.g., IF x is small THEN y is large, where small and large are viewed as labels of fuzzy sets. A fuzzy algorithm is an ordered sequence of instructions which may contain fuzzy assignment and conditional statements, e.g., x = very small, IF x is small THEN Y is large. The execution of such instructions is governed by the compositional rule of inference and the rule of the preponderant alternative. By relying on the use of linguistic variables and fuzzy algorithms, the approach provides an approximate and yet effective means of describing the behavior of systems which are too complex or too ill-defined to admit of precise mathematical analysis.
This chapter contains sections titled: Economic Action The concept of economic action Religious Ethics and Economic Rationality The Market: Its Impersonality and Ethic Class, Status, Party Economically Determined Power and the Status Order Determination of Class Situation by Market Situation Status Honor Parties
Living species are continuously subjected to all extrinsic forms of reactive oxidants and others that are produced endogenously. There is extensive literature on the generation and effects of reactive oxygen species (ROS) in biological processes, both in terms of alteration and their role in cellular signaling and regulatory pathways. Cells produce ROS as a controlled physiological process, but increasing ROS becomes pathological and leads to oxidative stress and disease. The induction of oxidative stress is an imbalance between the production of radical species and the antioxidant defense systems, which can cause damage to cellular biomolecules, including lipids, proteins and DNA. Cellular and biochemical experiments have been complemented in various ways to explain the biological chemistry of ROS oxidants. However, it is often unclear how this translates into chemical reactions involving redox changes. This review addresses this question and includes a robust mechanistic explanation of the chemical reactions of ROS and oxidative stress.
Understanding the processes by which practices become routinely embedded in everyday life is a long-standing concern of sociology and the other social sciences. It has important applied relevance in understanding and evaluating the implementation of material practices across a range of settings.This article sets out a theory of normalization processes that proposes a working model of implementation, embedding and integration in conditions marked by complexity and emergence. The theory focuses on the work of embedding and of sustaining practices within interaction chains, and helps in understanding why some processes seem to lead to a practice becoming normalized while others do not.
Childhood psychic trauma appears to be a crucial etiological factor in the development of a number of serious disorders both in childhood and in adulthood. Like childhood rheumatic fever, psychic trauma sets a number of different problems into motion, any of which may lead to a definable mental condition. The author suggests four characteristics related to childhood trauma that appear to last for long periods of life, no matter what diagnosis the patient eventually receives. These are visualized or otherwise repeatedly perceived memories of the traumatic event, repetitive behaviors, trauma-specific fears, and changed attitudes about people, life, and the future. She divides childhood trauma into two basic types and defines the findings that can be used to characterize each of these types. Type I trauma includes full, detailed memories, "omens," and misperceptions. Type II trauma includes denial and numbing, self-hypnosis and dissociation, and rage. Crossover conditions often occur after sudden, shocking deaths or accidents that leave children handicapped. In these instances, characteristics of both type I and type II childhood traumas exist side by side. There may be considerable sadness. Each finding of childhood trauma discussed by the author is illustrated with one or two case examples.
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In recent years the issue of supply chain risk has been pushed to the fore, initially by fears related to possible disruptions from the much publicised “millennium bug”. Y2K passed seemingly without incident, though the widespread disruptions caused by fuel protests and then Foot and Mouth Disease in the UK, and by terrorist attacks on the USA have underlined the vulnerability of modern supply chains. Despite increasing awareness among practitioners, the concepts of supply chain vulnerability and its managerial counterpart supply chain risk management are still in their infancy. This paper seeks to identify an agenda for future research and to that end the authors go on to clarify the concept of supply chain risk management and to provide a working definition. The existing literature on supply chain vulnerability and risk management is reviewed and compared with findings from exploratory interviews undertaken to discover practitioners' perceptions of supply chain risk and current supply chain risk management strategies.
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This text, in its second edition, provides a comprehensive introduction to insects, a group of animals that represent over half of the planet's biological diversity. It commences with a review of the significance of insects, their immense diversity and their patterns of distribution. Australian authors. 1. The importance and diversity of insects -- 2. External anatomy -- 3. Internal anatomy and physiology -- 4. Sensory systems and behaviour -- 5. Reproduction -- 6. Insect development and life histories -- 7. Insect systematics: phylogeny and evolution -- 8. Ground-dwelling insects -- 9. Aquatic insects -- 10. Insects and plants -- 11. Insect societies -- 12. Insect predation and parasitism -- 13. Insect defence -- 14. Medical and veterinary entomology -- 15. Pest management -- 16. Methods in entomology: collecting, preservation, curation and identification.
It is approaching a half century since Bill Stokoe published his revolutionary monograph, Sign Language Structure: An Outline of the Visual Communication Systems of the American Deaf It is rare for a work of innovative scholarship to spark a social as well as an intellectual revolution, but that is just what Stokoe's 1960 paper did. And it is indicative both of Stokoe's genius and of his commitment that he did not simply publish his groundbreaking work and then sit back to watch the revolutions unfold. He actively promoted important changes in at least three areas of social and intellectual life. First, and perhaps most important, his work, that was ultimately generally accepted as showing the signing of deaf people to be linguistic, supported significant changes in the way deaf children are educated around the globe. Second, his work led to a general rethinking of what is fundamental about human language; and, third, it helped to reenergize the moribund field of language origin studies. This truly revolutionary paper has been reprinted at least twice, in revised and original versions, since its initial release in 1960, and now, five years after Bill's death, it is good to see it once again brought before the general public.
The purpose of this department is to provide early announcement of significant new results, with some indications of proof. Although