Studies on exploiting semiochemicals for pest management in organic farming systems OF0188

This study addresses the extent to which pest management systems can exploit semiochemicals (defined below) in ways acceptable to organic farming, and determines where the science base needs to be expanded to accommodate specific problems arising in an increasing organic farming sector. It considers whether current knowledge of semiochemical release from particular crop plants, herbs and wild plant species could be investigated further in relation to organic farming practice and identifies how strategies of multiple cropping, that exploit known semiochemical interactions, could be applied to key pest problems in organic production. Where such exploitation is not feasible, other strategies using semiochemicals including traps, extracts of natural products and nature-identical synthetic products are considered. Finally, general and specific directions in which research and development could facilitate greater penetration of the use of semiochemicals in crop protection for organic farming are identified. Semiochemicals are natural products that, by acting as signals, regulate interactions between organisms e.g. plants and insects. Once the semiochemical interactions between a pest and its host plant have been elucidated they can be exploited to regulate the pest population, providing an alternative control strategy to conventional toxicants. The choice of approach by which the semiochemicals are deployed relates to three options, i.e. from a natural plant source, from an extract or as a nature identical synthetic product. However, even where the most natural situations of mixed cropping are used, the scientific basis of the interaction must be established for robustness and sustainability of the approach. A complete understanding of the process allows a risk assessment to be made of any problems that might ensue when exploiting natural systems in different configurations from those encountered naturally. A major approach to using semiochemical based pest control is to exploit ways of repelling pests from crop plants and attracting them towards trap plantations. Deploying semiochemicals generated naturally by plants is consistent with organic farming practice, where a range of mixed cropping techniques are employed already, which ‘unconsciously’ utilise semiochemical effects. Thus, the acceptance and use of systems exploiting aspects of semiochemical deployment demonstrate an emerging role in organic farming practices. However, as emphasised before, a comprehensive knowledge of the semiochemical interactions that underpin these techniques is vital if they are to be exploited fully. Other pest control approaches compatible with organic farming, such as encouragement of beneficial species and the use of reflective surfaces in mulches, may not involve semiochemical effects, but could be exploited more beneficially by integration with semiochemical practices. Semiochemicals generated naturally by plants can be used to influence beneficial organisms as well as invertebrate pests. For example, plant defence chemicals, induced by pest or pathogen infestation, can affect the behaviour of pests and their natural enemies. Semiochemicals can be employed to maximise the impact of parasitic organisms that attack pest populations, for example in the management of refugia for maintaining and increasing populations of these beneficial organisms. In addition, the approach can be applied against other organisms antagonistic to agriculture besides invertebrate pests, for example in weed control, where signals interfering with weed germination can be exploited. Extracts of natural products provide semiochemicals in a form that is familiar and acceptable to organic farming practice, where plant extracts are already used as toxicants or as semiochemical antifeedants and repellents. However, often the scientific basis for use of these materials is limited, and therefore, exploitation is also limited and can be unreliable. By understanding the composition and the mechanism of activity of semiochemicals, natural product extracts can be improved by selection of the best sources of natural materials and appropriate processes of extraction and formulation. Many natural products, particularly pheromones (semiochemicals acting between members of the same species), can be synthesised as nature-identical and the synthetic forms are often indistinguishable from the natural form. Synthesis can be expensive, but where possible, starting materials should be obtained from natural renewable resources. Nature-identical synthetic pheromones are used widely in parts of the world, either deployed in traps for monitoring, mass trapping and lure and kill strategies or for direct pest control approaches such as mating disruption. In addition, manipulation of beneficial species with pheromones is being investigated and synthetic food-related attractants and oviposition attractants have also been developed for pests where pheromones are not available. Already some nature-identical synthetic semiochemicals have been accepted as compatible with organic farming practice. The registration of many sex and aggregation pheromones has been possible because they are nature-identical and are deployed away from the crop or on crop areas that are not consumed. In most cases, semiochemicals, deployed alone, are not sufficiently robust to control pest populations directly. They are most effective when incorporated into strategies, such as the ‘push-pull’ strategy, that are integrated with other forms of pest control, e.g. pathogens, parasitoids and predators, mechanical barriers and resistant plant varieties. The integration of semiochemical approaches with other methods of pest population reduction will help prevent the development of pest resistance to the overall strategy. Since the integrated strategy comprises a number of components that affect different aspects of pest behaviour and development each component can be relatively ineffective when compared to conventional pesticides. However, this has the advantage of not selecting efficiently for resistance to any component of the strategy and thus contributes to the sustainability of the approach. Recommendations 1) Develop a priority list of specific and general problems in organic production to be targeted by semiochemical methodologies in addition to known problems such as in carrot and lettuce production, aphids on a range of vegetable crops and for fruit pests. 2) Develop semiochemical based control methods suitable for 1) and for the targets already known. 3) Provide scientific input, where lacking, for 1 and 2. 4) Encourage greater diversification in organic cropping systems, including agroforestry, so as to exploit current knowledge of semiochemical based control and to pave the way for new interventions as the science develops. 5) Consider semiochemical attributes of non-crop plant inputs including mulches, weeds and multifunctional beneficial plants and the roles that they might play in organic systems. 6) Initiate organic plant breeding programmes, specifically to exploit natural semiochemical release where understood, for crop and companion plants

Characterisation of friction and lubrication regimes in premium tubular connections

A friction test rig has been developed to carry out repeated sliding friction tests for premium tubular connections. The test rig enables accurate measurement of friction in various contact regimes which are relevant to the threaded connections between tubular components. Higher load tests can simulate the contact in metal-to-metal seals under very high contact pressures by using perpendicular pin-on-pin tests. The contact in the thread loading flank under intermediate pressures can be simulated by using larger radius coupon-on-coupon tests. The measured coefficient of friction is well correlated with a lubrication parameter combining lubricant film thickness and initial surface roughness. © 2012 Elsevier Ltd. All rights reserved

Using sports infrastructure to deliver economic and social change: Lessons for London beyond 2012

Over the last two decades, there has been a new trend emerging within sport, which has seen a shift, from investment for the sake of sport, to investment in sport for good (Sport England, 2008). In the context of the latter approach, there has been an emergence of the use of sport to address regeneration objectives, largely stemming from the belief of government and other sporting and non-sporting organizations, that it can confer a wide range of economic and social benefits to individuals and communities beyond those of a purely physical sporting nature, and can contribute positively to the revitalization of declining urban areas (BURA, 2003). This commentary will examine regeneration legacy in the context of the London Olympic Games. In particular, it will focus on the use of sports stadia as a tool for delivering economic and social change, and by drawing upon previous examples, suggest lessons London can learn to enhance regeneration legacies beyond 2012

Stories Have the Power to Save us: A Neurological Framework for the Imperative to Tell Stories

The evolutionary advantage of humans is in our unique ability to process stories – we have highly evolved ‘narrative organs.’ Through storytelling, vicarious knowledge, even guarded knowledge, is used to help our species survive. We learn, regardless of whether the story being told is ‘truth’ or ‘fiction.’ Humans place themselves in stories, as both observer and participant, to create a ‘neural balance’ or sweet spot that allows them to be immersed in a story without being entirely threatened by it – and this involvement in story leads to the formation of empathy – an empathy that is integral to forging a future humanity. It is through empathy, we argue, that stories have the power to save us. The hippocampi process narrative details. Situated alongside are the amygdalae – organs that place the reader in the story. The temporal lobes store ‘story nuggets.’ Finally there’s the frontal cortex to inhibit full participation in narrative, so that the story can be experienced vicariously

The glacier-influenced marine record on high-latitude continental margins: Synergies between modern, Quaternary and ancient evidence

Major glaciations or ‘ice ages’ are known to have affected the Earth's surface over the past three billion years. The best preserved records of these glaciations are often found in high-latitude continental margin settings where sediment has been delivered to, and then accumulated at, the edge of the ice sheet in thick glacier-influenced marine sequences. The composition and geometry of these deposits and the related assemblages of glacial landforms provide a wealth of information about the environmental setting during successive cycles of glaciation and deglaciation, including ice-dynamic and oceanographic processes. Here, we discuss modern (present day), Quaternary (last 2.6 myr) and ancient (last 1 gyr) high-latitude continental margin settings, and then contrast the methodologies used and glacier-influenced deposits and landforms most often identified for each time period. We use examples from the literature to identify synergies, as well as to note differences, between studies of glacier-influenced sediments from ancient to modern environments

Trends in colorectal cancer among Hispanics by stage and subsite location: 1989-2006

This is the final version of the article. Available from Springer Nature via the DOI in this record.OBJECTIVES: Hispanic colorectal cancer (CRC) rates historically have been lower than for non-Hispanic Whites in the United States and in Florida. The aim of this study is to understand CRC trends in Florida Hispanics and non-Hispanic Whites. METHODS: Using a cross-sectional study design, all invasive CRCs diagnosed among Florida residents between 1989 and 2006 were accessed from the Florida Cancer Data System (FCDS). These cases were analyzed by Hispanic and non-Hispanic White ethnic identification. The Hispanic Origin Identification Algorithm was applied to the FCDS data to identify Hispanic subjects. Primary cancer site and histology data were organized according to SEER (Surveillance Epidemiology and End Results) categories. Joinpoint regression was used to generate incidence trends by stage and subsite location. RESULTS: Rates of CRC incidence were higher for Florida Hispanics compared with non-Hispanic Whites since the mid 1990s. There was a consistent significant increase in the incidence of distant stage CRC in Hispanics (annual percent change (APC) of 1.26 and 0.90 in males and females), whereas rates in non-Hispanics decreased significantly during the same time period (APC -1.36 and -1.28, respectively). Similar trends were found in distant-stage right-sided CRC. Among right-sided CRCs, local stage incidence rate increased for both non-Hispanic Whites and Hispanics, whereas the incidence rate for regional stage decreased for both racial/ethnic groups. CONCLUSIONS: Trends for distant-stage CRC are increasing among Florida Hispanics. This is a particular public health concern given that CRC is a cancer for which screening modalities exist and could imply a concomitant increase in CRC-related mortality among Florida Hispanics. Lower rates of CRC screening in Hispanics are documented at the state level, relative to non-Hispanic Whites. Screening programs targeting the Florida Hispanic population are warranted.This work was supported by the Florida Department of Health (contract CODM7); the Florida Bankhead-Coley Cancer Research Program (#2BT02); the Centers for Disease Control and Prevention National Program of Cancer Registries; the Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine; and the European Regional Development Fund (ERDF) to University of Exeter

Increasing Student Engagement and Performance in Introductory Accounting through Student-Generated Screencasts

The paper reports the findings of a trial of student generated screencasts in an introductory accounting subject. This paper examines the effect of this screencast project on student engagement and performance. The effect on student engagement is examined using data from a pre and post screencast project student survey and performance effects examined by analysing the performance of students completing and not completing the project. The results of the study suggest the screencast project facilitated higher student engagement and performance. These findings have important implications for integrating technologies such as screencasting to facilitate enhanced learning outcomes in introductory accounting subjects

PacBio assembly of a Plasmodium knowlesi genome sequence with Hi-C correction and manual annotation of the SICAvar gene family.

Plasmodium knowlesi has risen in importance as a zoonotic parasite that has been causing regular episodes of malaria throughout South East Asia. The P. knowlesi genome sequence generated in 2008 highlighted and confirmed many similarities and differences in Plasmodium species, including a global view of several multigene families, such as the large SICAvar multigene family encoding the variant antigens known as the schizont-infected cell agglutination proteins. However, repetitive DNA sequences are the bane of any genome project, and this and other Plasmodium genome projects have not been immune to the gaps, rearrangements and other pitfalls created by these genomic features. Today, long-read PacBio and chromatin conformation technologies are overcoming such obstacles. Here, based on the use of these technologies, we present a highly refined de novo P. knowlesi genome sequence of the Pk1(A+) clone. This sequence and annotation, referred to as the 'MaHPIC Pk genome sequence', includes manual annotation of the SICAvar gene family with 136 full-length members categorized as type I or II. This sequence provides a framework that will permit a better understanding of the SICAvar repertoire, selective pressures acting on this gene family and mechanisms of antigenic variation in this species and other pathogens