982 resultados para defence


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Franz Josef Strauss, West German Minister of Atomic Energy and Minister of Defence, pursued a project by which European political integration was to be paralleled by co-operation in the field of nuclear energy and indeed nuclear weapons. It has often been alleged that this covered nationalist German ambitions to turn Germany into a nuclear power in its own rights. Seen in the context of his European integration programme - which foundered on the devotion of French President de Gaulle to French national sovereignty - Strauss' overall policy suggests that he did indeed aim not to obtain nuclear weapons for Germany, but for an integrated European superstate.

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Using figures derived from the UK Home Office, this paper analyses and reviews the impact and deployment of Part V of the Criminal Justice and Public Order Act 1994 since its enactment. This is done with special reference to its impact on citizenship and the regulation of ‘the environment’ and associated rural spaces. It is argued that, notwithstanding the actual use of the public order clauses in Part V of the Act, its underlying meanings are largely of a symbolic nature. Such symbolism is, however, a powerful indication of the defence of particularist constructions of rural space. It can also open out new conditions of possibility, providing a useful ‘oppressed’ status and media spectacle for a range of protesters and activists.

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Phytophagous insects have to contend with a wide variation in food quality brought about by a variety of factors intrinsic and extrinsic to the plant. One of the most important factors is infection by plant pathogenic fungi. Necrotrophic and biotrophic plant pathogenic fungi may have contrasting effects on insect herbivores due to their different infection mechanisms and induction of different resistance pathways, although this has been little studied and there has been no study of their combined effect. We studied the effect of the biotrophic rust fungus Uromyces viciae-fabae (Pers.) Schroet (Basidiomycota: Uredinales: Pucciniaceae) and the necrotrophic fungus Botrytis cinerea Pers. (Ascomycota: Helotiales: Sclerotiniaceae) singly and together on the performance of the aphid Aphis fabae Scop. (Hemiptera: Aphididae) on Vicia faba (L.) (Fabaceae). Alone, botrytis had an inhibitory effect on individual A. fabae development, survival and fecundity, while rust infection consistently enhanced individual aphids’ performance. These effects varied in linear relation to lesion or pustule density. However, whole-plant infection by either pathogen resulted in a smaller aphid population of smaller aphids than on uninfected plants, indicating a lowering of aphid carrying capacity with infection. When both fungi were applied simultaneously to a leaf they generally cancelled the effect of each other out, resulting in most performance parameters being similar to the controls, although fecundity was reduced. However, sequential plant infection (pathogens applied five days apart) led to a 70% decrease in fecundity and 50% reduction in intrinsic rate of increase. The application of rust before botrytis had a greater inhibitory effect on aphids than applying botrytis before rust. Rust infection increased leaf total nitrogen concentration by 30% while infection by botrytis with or without rust led to a 38% decrease. The aphids’ responses to the two plant pathogens individually is consistent with the alteration in plant nutrient content by infection and also the induction of different plant defence pathways and the possible cross-talk between them. This is the first demonstration of the complex effects of the dual infection of a plant by contrasting pathogens on insect herbivores. Key words: Vicia faba, Botrytis cinerea, Uromyces viciae-fabae, tripartite interactions, induced resistance

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Studying the pathogenesis of an infectious disease like colibacillosis requires an understanding of the responses of target hosts to the organism both as a pathogen and as a commensal. The mucosal immune system constitutes the primary line of defence against luminal micro-organisms. The immunoglobulin-superfamily-based adaptive immune system evolved in the earliest jawed vertebrates, and the adaptive and innate immune system of humans, mice, pigs and ruminants co-evolved in common ancestors for approximately 300 million years. The divergence occurred only 100 mya and, as a consequence, most of the fundamental immunological mechanisms are very similar. However, since pressure on the immune system comes from rapidly evolving pathogens, immune systems must also evolve rapidly to maintain the ability of the host to survive and reproduce. As a consequence, there are a number of areas of detail where mammalian immune systems have diverged markedly from each other, such that results obtained in one species are not always immediately transferable to another. Thus, animal models of specific diseases need to be selected carefully, and the results interpreted with caution. Selection is made simpler where specific host species like cattle and pigs can be both target species and reservoirs for human disease, as in infections with Escherichia coli.

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Each human body plays host to a microbial population which is both numerically vast (at around 1014 microbial cells) and phenomenally diverse (over 1,000 species). The majority of the microbial species in the gut have not been cultured but the application of culture-independent approaches for high throughput diversity and functionality analysis has allowed characterisation of the diverse microbial phylotypes present in health and disease. Studies in monozygotic twins, showing that these retain highly similar microbiota decades after birth and initial colonisation, are strongly indicative that diversity of the microbiome is host-specific and affected by the genotype. Microbial diversity in the human body is reflected in both richness and evenness. Diversity increases steeply from birth reaching its highest point in early adulthood, before declining in older age. However, in healthy subjects there appears to be a core of microbial phylotypes which remains relatively stable over time. Studies of individuals from diverse geopraphies suggest that clusters of intestinal bacterial groups tend to occur together, constituting ‘enterotypes’. So variation in intestinal microbiota is stratified rather than continuous and there may be a limited number of host/microbial states which respond differently to environmental influences. Exploration of enterotypes and functional groups may provide biomarkers for disease and insights into the potential for new treatments based on manipulation of the microbiome. In health, the microbiota interact with host defences and exist in harmonious homeostasis which can then be disturbed by invading organisms or when ‘carpet bombing’ by antibiotics occurs. In a portion of individuals with infections, the disease will resolve itself without the need for antibiotics and microbial homeostasis with the host’s defences is restored. The administration of probiotics (live microorganisms which when administered in adequate amounts confer a health benefit on the host) represents an artificial way to enhance or stimulate these natural processes. The study of innate mechanisms of antimicrobial defence on the skin, including the production of numerous antimicrobial peptides (AMPs), has shown an important role for skin commensal organisms. These organisms may produce AMPs, and also amplify the innate immune responses to pathogens by activating signalling pathways and processing host produced AMPs. Research continues into how to enhance and manipulate the role of commensal organisms on the skin. The challenges of skin infection (including diseases caused by multiply resistant organisms) and infestations remain considerable. The potential to re-colonise the skin to replace or reduce pathogens, and exploring the relationship between microbiota elsewhere and skin diseases are among a growing list of research targets. Lactobacillus species are among the best known ‘beneficial’ bacterial members of the human microbiota. Of the approximately 120 species known, about 15 are known to occur in the human vagina. These organisms have multiple properties, including the production of lactic acid, hydrogen peroxide and bacteriocins, which render the vagina inhospitable to potential pathogens. Depletion of the of the normal Lactobacillus population and overgrowth of vaginal anaerobes, accompanied by the loss of normal vaginal acidity can lead to bacterial vaginosis – the commonest cause of abnormal vaginal discharge in women. Some vaginal anaerobes are associated with the formation of vaginal biofilms which serve to act as a reservoir of organisms which persists after standard antibiotic therapy of bacterial vaginosis and may help to account for the characteristically high relapse rate in the condition. Administration of Lactobacillus species both vaginally and orally have shown beneficial effects in the treatment of bacterial vaginosis and such treatments have an excellent overall safety record. Candida albicans is a frequent coloniser of human skin and mucosal membranes, and is a normal part of the microbiota in the mouth, gut and vagina. Nevertheless Candida albicans is the most common fungal pathogen worldwide and is a leading cause of serious and often fatal nosocomial infections. What turns this organism from a commensal to a pathogen is a combination of increasing virulence in the organism and predisposing host factors that compromise immunity. There has been considerable research into the use of probiotic Lactobacillus spp. in vaginal candidiasis. Studies in reconstituted human epithelium and monolayer cell cultures have shown that L. rhamnosus GG can protect mucosa from damage caused by Candida albicans, and enhance the immune responses of mucosal surfaces. Such findings offer the promise that the use of such probiotic bacteria could provide new options for antifungal therapy. Studies of changes of the human intestinal microbiota in health and disease are complicated by its size and diversity. The Alimentary Pharmabiotic Centre in Cork (Republic of Ireland) has the mission to ‘mine microbes for mankind’ and its work illustrates the potential benefits of understanding the gut microbiota. Work undertaken at the centre includes: mapping changes in the microbiota with age; studies of the interaction between the microbiota and the gut; potential interactions between the gut microbiota and the central nervous system; the potential for probiotics to act as anti-infectives including through the production of bacteriocins; and the characterisation of interactions between gut microbiota and bile acids which have important roles as signalling molecules and in immunity. The important disease entity where the role of the gut microbiota appears to be central is the Irritable Bowel Syndrome (IBS). IBS patients show evidence of immune activation, impaired gut barrier function and abnormal gut microbiota. Studies with probiotics have shown that these organisms can exert anti-inflammatory effects in inflammatory bowel disease and may strengthen the gut barrier in IBS of the diarrhoea-predominant type. Formal randomised trials of probiotics in IBS show mixed results with limited benefit for some but not all. Studies confirm that administered probiotics can survive and temporarily colonise the gut. They can also stimulate the numbers of other lactic acid bacilli in the gut, and reduce the numbers of pathogens. However consuming live organisms is not the only way to influence gut microbiota. Dietary prebiotics are selectively fermented ingredients that can change the composition and/or activity of the gastrointestinal microbiota in beneficial ways. Dietary components that reach the colon, and are available to influence the microbiota include poorly digestible carbohydrates, such as non-starch polysaccharides, resistant starch, non-digestible oligosaccharides (NDOs) and polyphenols. Mixtures of probiotic and prebiotic ingredients that can selectively stimulate growth or activity of health promoting bacteria have been termed ‘synbiotics’. All of these approaches can influence gut microbial ecology, mainly to increase bifidobacteria and lactobacilli, but metagenomic approaches may reveal wider effects. Characterising how these changes produce physiological benefits may enable broader use of these tactics in health and disease in the future. The current status of probiotic products commercially available worldwide is less than ideal. Prevalent problems include misidentification of ingredient organisms and poor viability of probiotic microorganisms leading to inadequate shelf life. On occasions these problems mean that some commercially available products cannot be considered to meet the definition of a probiotic product. Given the potential benefits of manipulating the human microbiota for beneficial effects, there is a clear need for improved regulation of probiotics. The potential importance of the human microbiota cannot be overstated. ‘We feed our microbes, they talk to us and we benefit. We just have to understand and then exploit this.’ (Willem de Vos).

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This paper investigates whether and to what extent a wide range of actors in the UK are adapting to climate change, and whether this is evidence of a social transition. We document evidence of over 300 examples of early adopters of adaptation practice to climate change in the UK. These examples span a range of activities from small adjustments (or coping), to building adaptive capacity, to implementing actions and to creating deeper systemic change in public and private organisations in a range of sectors. We find that adaptation in the UK has been dominated by government initiatives and has principally occurred in the form of research into climate change impacts. These government initiatives have stimulated a further set of actions at other scales in public agencies, regulatory agencies and regional government (and the devolved administrations), though with little real evidence of climate change adaptation initiatives trickling down to local government level. The sectors requiring significant investment in large scale infrastructure have invested more heavily than those that do not in identifying potential impacts and adaptations. Thus we find a higher level of adaptation activity by the water supply and flood defence sectors. Sectors that are not dependent on large scale infrastructure appear to be investing far less effort and resources in preparing for climate change. We conclude that the UK government-driven top-down targeted adaptation approach has generated anticipatory action at low cost in some areas. We also conclude that these actions may have created enough niche activities to allow for diffusion of new adaptation practices in response to real or perceived climate change. These results have significant implications for how climate policy can be developed to support autonomous adaptors in the UK and other countries.

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Background: Monosporascus cannonballus is the main causal agent of melon vine decline disease. Several studies have been carried out mainly focused on the study of the penetration of this pathogen into melon roots, the evaluation of symptoms severity on infected roots, and screening assays for breeding programs. However, a detailed molecular view on the early interaction between M. cannonballus and melon roots in either susceptible or resistant genotypes is lacking. In the present study, we used a melon oligo-based microarray to investigate the gene expression responses of two melon genotypes, Cucumis melo 'Piel de sapo' ('PS') and C. melo 'Pat 81', with contrasting resistance to the disease. This study was carried out at 1 and 3 days after infection (DPI) by M. cannonballus. Results: Our results indicate a dissimilar behavior of the susceptible vs. the resistant genotypes from 1 to 3 DPI. 'PS' responded with a more rapid infection response than 'Pat 81' at 1 DPI. At 3 DPI the total number of differentially expressed genes identified in 'PS' declined from 451 to 359, while the total number of differentially expressed transcripts in 'Pat 81' increased from 187 to 849. Several deregulated transcripts coded for components of Ca2+ and jasmonic acid (JA) signalling pathways, as well as for other proteins related to defence mechanisms. Transcriptional differences in the activation of the JA-mediated response in 'Pat 81' compared to 'PS' suggested that JA response might be partially responsible for their observed differences in resistance. Conclusions: As a result of this study we have identified for the first time a set of candidate genes involved in the root response to the infection of the pathogen causing melon vine decline. This information is useful for understanding the disease progression and resistance mechanisms few days after inoculation.

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Mathematics in Defence 2011 Abstract. We review transreal arithmetic and present transcomplex arithmetic. These arithmetics have no exceptions. This leads to incremental improvements in computer hardware and software. For example, the range of real numbers, encoded by floating-point bits, is doubled when all of the Not-a-Number(NaN) states, in IEEE 754 arithmetic, are replaced with real numbers. The task of programming such systems is simplified and made safer by discarding the unordered relational operator,leaving only the operators less-than, equal-to, and greater than. The advantages of using a transarithmetic in a computation, or transcomputation as we prefer to call it, may be had by making small changes to compilers and processor designs. However, radical change is possible by exploiting the reliability of transcomputations to make pipelined dataflow machines with a large number of cores. Our initial designs are for a machine with order one million cores. Such a machine can complete the execution of multiple in-line programs each clock tick

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This chapter aims to discuss the relationship between femininity and representations of women involved in violence, focussing on visual representations. Miranda Alison has made the point that the repeated necessity to qualify the term 'combatant' with the descriptor 'female' draws attention to how women soldiers, female freedom fighters, female suicide bombers and female terrorists are exceptional figures. That the female combatant or the female terrorist is an aberration or a deviation from a masculine norm is undermined by the lengthy history of women as warriors, fighters, and terrorists. In that sense it is not so much that fighting women are rare but that there is amnesia within cultural memories concerning the woman fighter. However, in representations of conflict, the dominant image associated with femininity is passive; that is as the defenceless and the defended, or as the allegory of peace. Moreover, representations of men in wars as defeated or wounded means feminising such figures. Miriam Cooke, in her Women and the War Story, 1996, points out how a mythic war story provides men with political roles, in the politikon or public arena, whereas women are domesticated in the space of the oikon. In the mythic war story women may function as Mater Dolorosa, Patriotic Mother or Spartan Mother. It follows then that there are conditions in which it is permissible to represent women fighting on behalf of their children or in defence of the home, and in the absence of men. These images are also found in wider culture: Sarah Connor in Terminator or Ripley in Alien, for example. Images of the female terrorist raise new issues but I want to argue that it is also the case that discussing femininity and the terrorist must involve relating such imagery to representations of the female warrior over a longer timespan. Some questions have shifted since the late twentieth century. Dating from the early 1990s, most Western nations increasingly incorporated women into combat roles within their armed forces. This paper will aim to unpick some of the intricate connections between the increasing presence of women in the armed forces, what relationship this has to emancipation and the participation of women in violence classed as terrorist.

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Grassland ecosystems comprise a major portion of the earth’s terrestrial surface, ranging from high-input cultivated monocultures or simple species mixtures to relatively unmanaged but dynamic systems. Plant pathogens are a component of these systems with their impact dependent on many interacting factors, including grassland species population dynamics and community composition, the topics covered in this paper. Plant pathogens are affected by these interactions and also act reciprocally by modifying their nature. We review these features of disease in grasslands and then introduce the 150-year long-term Park Grass Experiment (PGE) at Rothamsted Research in the UK. We then consider in detail two plant-pathogen systems present in the PGE, Tragopogon pratensis-Puccinia hysterium and Holcus lanata-Puccinia coronata. These two systems have very different life history characteristics: the first, a biennial member of the Asteraceae infected by its host-specific, systemic rust; the second, a perennial grass infected by a host-non-specific rust. We illustrate how observational, experimental and modelling studies can contribute to a better understanding of population dynamics, competitive interactions and evolutionary outcomes. With Tragopogon pratensis-Puccinia hysterium, characterised as an “outbreak” species in the PGE, we show that pathogen-induced mortality is unlikely to be involved in host population regulation; and that the presence of even a short-lived seed-bank can affect the qualitative outcomes of the host-pathogen dynamics. With Holcus lanata-Puccinia coronata, we show how nutrient conditions can affect adaptation in terms of host defence mechanisms, and that co-existence of competing species affected by a common generalist pathogen is unlikely.

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The infant gut microbiota plays an important role in the development of the infant immune and gastrointestinal systems. We investigated whether increased salmon consumption during pregnancy, maternal weight gain during pregnancy or infant mode of feeding alter markers of gut immune defence and inflammation. Women (n = 123) who rarely ate oily fish were randomly assigned to remain on their habitual diet or to consume two 150 g portions of farmed salmon per week from 20 weeks pregnancy until delivery. At 38 weeks gestation the women (n = 75) provided a faecal sample and on days 7, 14, 28 and 84 post-partum, faecal samples were collected from the infants (n = 38). Fluorescence in situ hybridisation was used to determine the composition of the faecal microbiota and ELISA to measure faecal sIgA and calprotectin concentrations. There was no effect of salmon consumption on the faecal microbiota of the mothers or on faecal sIgA and calprotectin concentrations in either mothers or infants. Degree of weight gain influenced the maternal faecal microbiota and mode of infant feeding influenced the infant faecal microbiota. Faecal samples from infants in the salmon group tended to have lower counts of Atopobium cluster compared with those in the control group (P = 0.097). This difference was significant in formula-fed infants (P < 0.05), but not exclusively breast-fed infants. In conclusion, the impact of oily fish consumption during pregnancy on maternal and infant gut microbiota composition is limited, but significant differences were associated with maternal weight gain during pregnancy and infant mode of feeding.

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Probiotic bacteria have gained popularity as a defence against disorders of the bowel. However, the acid sensitivity of these cells results in a loss of viability during gastric passage and, consequently, a loss of efficacy. Probiotic treatment can be supplemented using ‘prebiotics’, which are carbohydrates fermented specifically by probiotic cells in the body. This combination of probiotic and prebiotic is termed a ‘synbiotic’. Within this article a multiparticulate dosage form has been developed, consisting of poly(d,l-lactic-co-glycolic acid) (PLGA) microcapsules containing prebiotic Bimuno™ incorporated into an alginate–chitosan matrix containing probiotic Bifidobacterium breve. The aim of this multiparticulate was that, in vivo, the probiotic would be protected against gastric acid and the release of the prebiotic would occur in the distal colon. After microscopic investigation, this synbiotic multiparticulate was shown to control the release of the prebiotic during in vitro gastrointestinal transit, with the release of galacto-oligosaccharides (GOS) initially occurred over 6 h, but with a triphasic release pattern giving further release over 288 h. Encapsulation of B. breve in multiparticulates resulted in a survival of 8.0 ± 0.3 log CFU/mL cells in acid, an improvement over alginate–chitosan microencapsulation of 1.4 log CFU/mL. This was attributed to increased hydrophobicity by the incorporation of PLGA particles.

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In theory, enrichment of resource in a predator-prey model leads to destabilization of the system, thereby collapsing the trophic interaction, a phenomenon referred to as "the paradox of enrichment". After it was first proposed by Rosenzweig (1971), a number of subsequent studies were carried out on this dilemma over many decades. In this article, we review these theoretical and experimental works and give a brief overview of the proposed solutions to the paradox. The mechanisms that have been discussed are modifications of simple predator-prey models in the presence of prey that is inedible, invulnerable, unpalatable and toxic. Another class of mechanisms includes an incorporation of a ratio-dependent functional form, inducible defence of prey and density-dependent mortality of the predator. Moreover, we find a third set of explanations based on complex population dynamics including chaos in space and time. We conclude that, although any one of the various mechanisms proposed so far might potentially prevent destabilization of the predator-prey dynamics following enrichment, in nature different mechanisms may combine to cause stability, even when a system is enriched. The exact mechanisms, which may differ among systems, need to be disentangled through extensive field studies and laboratory experiments coupled with realistic theoretical models.

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This article reflects on a decade of British counterinsurgency operations. Questioning the idea that lessons have been learnt, the paper challenges the assumptions that are being used to frame future strategic choice. Suggesting that defence engagement is primarily focused on optimising overseas interventions while avoiding a deeper strategic reassessment about whether the UK should be undertaking these sorts of activities, the article calls for a proper debate on Britain's national security interests.

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The IEEE 754 standard for oating-point arithmetic is widely used in computing. It is based on real arithmetic and is made total by adding both a positive and a negative infinity, a negative zero, and many Not-a-Number (NaN) states. The IEEE infinities are said to have the behaviour of limits. Transreal arithmetic is total. It also has a positive and a negative infinity but no negative zero, and it has a single, unordered number, nullity. We elucidate the transreal tangent and extend real limits to transreal limits. Arguing from this firm foundation, we maintain that there are three category errors in the IEEE 754 standard. Firstly the claim that IEEE infinities are limits of real arithmetic confuses limiting processes with arithmetic. Secondly a defence of IEEE negative zero confuses the limit of a function with the value of a function. Thirdly the definition of IEEE NaNs confuses undefined with unordered. Furthermore we prove that the tangent function, with the infinities given by geometrical con- struction, has a period of an entire rotation, not half a rotation as is commonly understood. This illustrates a category error, confusing the limit with the value of a function, in an important area of applied mathe- matics { trigonometry. We brie y consider the wider implications of this category error. Another paper proposes transreal arithmetic as a basis for floating- point arithmetic; here we take the profound step of proposing transreal arithmetic as a replacement for real arithmetic to remove the possibility of certain category errors in mathematics. Thus we propose both theo- retical and practical advantages of transmathematics. In particular we argue that implementing transreal analysis in trans- floating-point arith- metic would extend the coverage, accuracy and reliability of almost all computer programs that exploit real analysis { essentially all programs in science and engineering and many in finance, medicine and other socially beneficial applications.