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How do humans physically interact with the environment or with other humans? It is well known that the nervous system can modify the body's stiffness by selectively cocontracting muscles to shape the mechanical interaction with the environment, but how this influences haptic perception is not known. This thesis examines whether humans can adapt muscles' activation to influence their perception of the physical interaction with the environment. This question is investigated by conducting behavioural experiments using dedicated robotic interfaces to study sensorimotor interactions in the presence of haptic and visual perturbations. Hypotheses about the underlying mechanism are then tested through mathematical modelling and simulations. Chapter 1 reviews related frameworks and introduces the most relevant questions addressed in this work. Chapter 2 then shows that the central nervous system (CNS) can voluntarily adapt muscle cocontraction to increase haptic sensitivity. In an experiment, participants tracked a randomly moving target with visual noise while being physically guided by a virtual elastic band, where the band's stiffness was controlled by their muscle coactivation. The results show that participants learned to increase cocontraction with visual noise and decrease it when the guidance is incongruent with the visual target. The adaptation law governing the regulation of the body's stiffness by the CNS is then derived through computational modelling. This model is designed to maximise visuo-haptic information while minimising metabolic cost, thus trading off sensory information with energy. Further, it is shown in Chapter 3 that when the subjects are coupled via a tuneable connection to a robotic guidance designed to hinder their tracking through perturbations at the turning points (where participants physiologically increase cocontraction), they adapted cocontraction to reduce the impact of perturbations on performance. These results highlight the CNS ability to modify the muscle activation patterns to improve performance with minimal effort. Chapter 4 tests the robustness of human adaptive haptic sensing introduced in the previous chapters for human-human physical interaction. For example, in tango dancing physical contact provides haptic information of the partner's action required to coordinate the movements. During such physical interactions, should one keep the arms compliant so that the partner can correct the motion, or should one stiffen them to better keep along the planned movement? Using a tracking task in which a dyad is coupled via a rigid connection, subjects readily adapted the compliance of their limb depending on both the accuracy of the partner's and their own movement. The same computational model introduced in Chapter 2 could explain these results and predict the experimentally observed cocontraction adaptation. This suggests that the minimisation of prediction error and energy is a general principle also holding in interpersonal interactions. Altogether, these findings shed light on how humans can adapt haptic sensing by changing body properties, and propose a novel framework to interpret visuo-haptic perception for interaction with the environment and other humans.

This research project addresses the question of how political elites' behaviour varies when competition among them is heightened. Focusing on changing political orders across Africa and the Middle East, it seeks to understand how political elites facing internal and external challenges manipulate local power structures for political survival purposes, resulting in distinct political trajectories. The thesis argues that local political and conflict environments are conditional on the nature of competition among elites. Volatile political transitions, intense popular unrest, and militarised environments all create distinct incentives and constraints which shape political orders, and determine the inclusion or exclusion of select elites in the resulting political settlement. Using a mixed-method research design which combines quantitative and qualitative methodologies, the thesis consists of five essays exploring select topics and three in-depth case studies. The essays address two cross-cutting themes. First, they show how elites reconfigure institutional structures to cement alliances and survive internal or external challenges when power is being contested after a change in the leadership, or when facing popular mobilisation. Bargaining occurs through ministerial appointments or purges which aim to consolidate political settlements and secure power holders from rivals. Examples from Tunisia and recent episodes of leadership changes from across Africa are presented together with original datasets of ministerial appointments. Second, the essays illustrate how patterns of violence within states are indicative of the fragmented nature of the political environment of the political competition therein taking place. Findings from Libya and Yemen are presented to demonstrate that localised fragmentation produce subnational geographies of conflict which reflect the strategies and the mobilisation capacity of armed groups and elite actors.

According to the data from government institutions (Energy Information Administration, 2012), the consumption of energy will show an average growth of 42.5% by 2035 from the heating, ventilation and air conditioning devices solely (Perez-Lombard et al., 2008). For this reason the interest in technologies that can reduce the consumption of energy for heating or cooling houses is growing. In particular, the glazing of houses could offer great potential for energy saving as these elements of the building envelopment still have a margin for improvement. Currently, the research is focusing on stopping the heat exchange through radiative transfer. The problems of the current technologies are associated with the high costs and the colour they give to windows. Technologies using nanoparticles have started to emerge and have shown promise as methods for absorbing the radiation which passes through the glazing. Thanks to the unique control over their size and shape dependent properties, their absorbance can be moved to lower energy and this can satisfy both the requirements of stopping the heat carrying radiation and still providing a good illumination. Through the wide range of nanoparticle materials, sizes and shapes, silver triangular nanoprisms are a promising candidate for further research due to their strong absorption in the near infrared region. As their synthesis and the control over their geometrical properties are challenging using conventional batch-based macro reactor systems, a novel microreactor system was developed in this study in order to continuously produce silver triangular nanoprisms and monitoring their optical properties by mean of integrated spectroscopy techniques. By using sol-gel chemistry, the particles were coated with a shell of SiO2 which can further be functionalised with various chemical functional groups such as thiol and allyl. Coated particles were then embedded in polymeric matrix (i.e. poly(methylmethacrylate), or PMMA) with covalent interactions between the polymer and the functional groups attached to the silica shell surface. Finally, the composite solutions were casted onto a glass-slide and the optical performance was evaluated using spectroscopic methodologies. Compared to similar composite materials, the systems herein reported offers several advantages, such as the low coloration in the visible spectrum and no risk of aggregation of the metal nuclei once they are dispersed in the polymer matrix. The use of a microreactor can also grant good control over high volumes of such colloids, opening to the possibility for a large scale production of such materials.

Research and development in aquaculture has supported the knowledge-based development of the sector over the last decades. In particular, species diversification is playing an important role to ensure sustainability of the industry and helping to reduce pressure on wild stocks of those aquatic species for which farming technology is still at the early stages. Due to the increasing pressures on more traditional carnivorous marine finfish species (aquafeed reliance on fishmeal and fish oil, environmental impact, market price) low trophic organisms are receiving more attention to provide sustainable alternatives and integrate production activities with the aim of reducing environmental impacts and to provide secondary high value crops. Integrated Multi-Trophic Aquaculture (IMTA) systems are therefore at the forefront of innovation in the industry. Several invertebrate species have been investigated and tested as integral part of IMTA (mussels, oysters, abalone and macroalgae) and echinoderms have also been considered as good candidates for the future development of this technology. In order to allow for a more widespread uptake of integrated aquaculture, several technical and biological challenges need to be overcome, including a reliable supply of juveniles. In recent years, this has prompted investigation on Echiniculture as a whole and on hatchery technologies in particular. This PhD investigated key constraints in edible sea urchin (Paracentrotus lividus) juvenile production with the aim to improve commercial sea urchin hatchery outputs. The research firstly focused on larval nutrition (Chapter 3 and 4) and specifically tested the hypothesis that larvae required higher dietary inputs of long chain fatty acids than those provided by Dunaliella tertiolecta, a microalgae species widely used in echinoderm larval rearing. Fatty acid composition of P. lividus eggs, investigated in Chapter 3, supported this hypothesis, which was further confirmed by the results obtained in Chapter 4 where microalgae (Cricosphaera elongata, Pleurochrisis carterae and Tetraselmis suecica) with a more balanced fatty acid profile, in particular richer in long chain fatty acids, were employed. This resulted in a significantly improved larval development and survival. Results also indicated that these alternative microalgae species could be successfully grown without modification of the microalgae production protocols in the hatchery where the experimentation had taken place. The third experimental chapter compared static and flow through systems which provides more stable water quality through constant water exchange and reduces larval handling and associated stress. Results indicated that larval survival was significantly improved by the flow-through system and the need for tank cleaning was reduced (three versus seven times per larval cycle when using flow-through and static rearing systems respectively). However, water quality, based on the parameters assessed (NH4, PO4-3, NO2 and NO3), did not show any significant differences between systems. Reduced handling could have therefore played the most important role in promoting larval survival. Both these trials resulted in a significant 5 to 20 % increased survival. A follow-up study, combining flow-through with more suitable microalgae, should be carried out and could result in even further enhanced survival. Then, chapters 6 and 7 focused on broodstock nutrition and subsequent improvement of gamete quantity and quality. These two trials aimed to explore and describe the biological effects that some important nutrients, such as proteins, lipids, fatty acids and carotenoids, have on urchins’ somatic and gonadal growth, gonad biochemical composition during gametogenesis, fecundity and maternal provisioning to developing embryos. Results from the experiment described in Chapter 6 indicated that higher protein content can improve somatic growth in P. lividus adults and that more expensive, protein-, lipid- and energy-rich diets do not significantly enhance fecundity or offspring performance. Results, moreover, highlighted the need for a specifically formulated broodstock diet and gave some insights into what its composition should be, especially in relation to carotenoids. In Chapter 7, fatty acid profiles of P. lividus gonads throughout gametogenesis were studied for the first time. It was observed that, among Long Chain Polyunsaturated Fatty Acids (LC-PUFAs), Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) are primarily accumulated during gametogenesis, whilst Arachidonic acid (ARA) appears to be independent of dietary input. In addition, it was clearly shown that ARA is the only LC-PUFA accumulated in the eggs along with Non Methylene Interrupted Fatty Acids (NMI FAs). As well as looking at the biological effects of different diets on fatty acid profiles of gonadal and larval tissues, the work also expanded on a more fundamental level to explore the metabolic pathway through which precursors could be used by sea urchins for the endogenous production of long chain fatty acids (Chapter 8). Three Expressed Sequence Tags (ESTs) for putative fatty acyl desaturases, one of which was closely related to Octopus vulgaris ∆5-like fatty acyl desaturase, were identified. The newly cloned putative desaturase of P. lividus possessed all typical features of other fatty acyl desaturases. However, because of time constraints, functional characterisation, originally planned, of the new protein could not be performed and further research effort is needed to investigate this important aspect of sea urchin physiology. Overall, the aim of this research project has been achieved as it provided a set of exploitable results and protocols to improve hatchery practices for the production of P. lividus juvenile. However, more research is required to investigate some of the underlying mechanisms behind the observed biological effects such as delay in larval development when T. suecica was used as larval feed, increased broodstock fecundity, improved larval survival in the flow-through system and higher gonadal concentration of some fatty acids (mainly DHA) than provided in the feed.

The process by which the classical music business operates in the UK changed significantly through the marketing of a classical music recording which took place in 1989. EMI’s recording of Vivaldi’s work Four Seasons with the violinist Nigel Kennedy was given a unique marketing campaign for a classical music recording. Instead of the traditional marketing approach for a classical music release, pop marketing techniques were employed. In a different but related development, in 1990, the first of the Three Tenors concerts was held in Rome to mark the final match of the 1990 Fédération Internationale de Football Association’s (FIFA) world cup competition. The success of this second record campaign lay in the novelty of three tenors performing together at a football competition. The result was classical music achieving worldwide exposure through global radio and television broadcasts. Both case studies help further classical music as a form of popular culture. Earlier precedent demonstrates pieces of classical music being used for adverts or films and becoming popular. For example Ravel’s Bolero was used in a seduction scene in the film 10 between Bo Derek and Dudley Moore in 1984, and by ice-skaters Torvill and Dean in the same year for the final of the 1984 Winter Olympics. Another example is Orff’s Carmina Burana sections of which have been used for aftershave and lager adverts as well as being sung at football matches. Because the reach of the audience is larger than that in a traditional classical music setting, the pieces achieve a mass cultural perspective in this context. My thesis examines the impact that the success of the Four Seasons and Three Tenors releases had on the classical music business and the development in marketing and selling techniques that emanated from their success. Examples of marketing campaigns post the Four Seasons are included to show the extent of non-traditional classical marketing techniques used subsequently by the classical music industry, some of which I devised and implemented. My research also analyses how trading over the internet has had an impact on the music business as a whole, and how the classical music sector has followed the pop area of the music industry in creating different ways of selling to traditional and new consumers through online trading. This part of the thesis focuses on the period between 2000-2010, especially from 2006 when developments in this field progressed. My study will draw on a Case Study approach using multiple data collection methods. Also employed is descriptive analysis using a combination of qualitative and quantitative techniques, in particular through industry reports. The reasons for the sales success of both recordings are examined in my thesis. The Four Seasons achieved 2 million sales and an entry into the Guinness Book of Records as the best-selling classical music recording of all time at that point. The recording of the 1990 Three Tenors concert and the successive recordings of similar concerts in 1994 and 1998 led to these albums becoming the all-time best-selling classical recordings. For example, worldwide sales for the 1990 recording reached over 12 million CDs, cassettes and videos combined and 23 million for the 1990, 1994 and 1998 Three Tenors recordings. These projects not only gave increased exposure to the classical music genre by expanding its traditional consumer reach, they also created a force for change in business models affecting the marketing and visibility of classical music since 1989. A further significant factor in the success of these vocal recordings (as well as the chance for classical music to be heard outside its traditional boundary) was the use of the arresting aria Nessun dorma from Puccini’s opera Turandot. This was sung by Pavarotti and used by the BBC for all its programmes broadcasting the 1990 football matches in the competition. The effect of internet selling and downloading on the music business was encouraged by the creation of Apple’s iTunes program in 2001. The invention of the iPod in 2002 and the legal entity of Napster in 2004 led to much increased accessibility of music. For classical music with its long movements and being part of a slow-moving market (compared to pop music), this area of the business only witnessed an increase in activity through the expansion of Broadband nationally during 2006 and 2007, reaching 70% in 2009 (discussed on page 90, chapter 4). Since then, the growth of classical music e-tailers has forged a new way of operating in the classical music field. The thesis will give examples of the leading companies trading over the internet and their influence on the classical music market. Contributions from practitioners in the music business inform my thesis through their own witnessing of changes in the classical music business since the Four Seasons campaign. My own experience as a former Head of Press and Promotion for both Decca Classics and EMI Classics, and also currently as a marketing and business consultant for classical music organisations, offers a useful and relevant addition to my research. My contribution to knowledge is to identify the adaptation of pop music marketing tools by the classical music industry over a 20 year time frame. My close involvement in the EMI Four Seasons campaign places me in a unique position to identify and evaluate the significance of the publicity campaign of that recording not only at that time but in the years that followed.

This research project focussed on using the molecular imprinting approach for the synthesis of nanogels capable of catalysing the cross-aldol reaction between 4-nitrobenzaldehyde and acetone. A polymerisable proline derivative was used as the functional monomer to mimic the enamine-based mechanism of aldolase type I enzymes. A 1,3-diketone template, used to create the cavity, was designed to imitate the intermediate of the aldol reaction and was bound to the functional monomer using a reversible covalent interaction prior to polymerisation. Soluble imprinted nanogels were prepared by using a high-dilution radical polymerisation, which was followed by template removal and estimation of active site concentrations by monitoring the release of 4-nitrophenolate due to the acetylation of proline units with 4-nitrophenyl acetate. Analysis by DLS and TEM confirmed an average particle size of 20 nm for the nanogel preparations, comparable to the size of natural enzymes, and an average molecular mass ranging from 258 to 288 kDa, as determined by GPLC using polymethylmethacrylate standards. The polymers were found to be soluble in DMF, DMSO and mixtures thereof, giving rise to homogeneous solutions. The kinetic characterisation of both imprinted and non-imprinted nanogels was carried out with catalyst concentrations between 0.7 and 3.5% mol. Imprinted nanogel MIP-AS147 was found to have a kcat value of 0.26 × 10-2 min-1, the highest value ever achieved with imprinted nanogels catalysing C-C bond formation. Comparison of the catalytic constants for both imprinted nanogel MIP-AS147 and non-imprinted nanogel NIP-AS133 gave a ratio of kcatMIP /kcatNIP = 20, which is indicative of good imprinting efficiency and highlights the significance of the template during the imprinting process. Analysis of the stereoselectivity of the reaction catalysed by nanogels gave 62% ee, which is comparable with the one of the “free” catalyst. This work is the first and so far only example of imprinted polymer capable of catalysing the cross-aldol addition. The kinetic data obtained provide additional evidence to the hypothesis that the nanogel format is superior to ‘bulk’ polymers for the generation of enzymelike catalysts.

Attention Deficit/Hyperactivity Disorder (ADHD) is one of the most prevalent childhood disorders in the United States. Although many children with an ADHD diagnosis are prescribed medication to control symptoms, behavioral concerns are still regularly noted in the classroom, home, and other settings. Therefore, school psychologists are often called upon to assist teachers and families with developing intervention procedures. The purpose of this research was to investigate the relationship between mindfulness training, the cognitive processes of attention regulation, and behavior of children who have been diagnosed with ADHD. This study utilized a multiple baseline across participant's design where each student was tracked over time following a baseline (pre-intervention) condition. Four 8-year-old male participants with a primary diagnosis of ADHD and a significant number of off-task classroom behaviors were included in this study. Teacher and parent ratings of the Behavior Assessment System for Children, Second Edition (BASC-2) and Behavior Rating Inventory of Executive Function (BRIEF) were completed pre- and posttest for each participant. The Reliable Change Index (RCI) was calculated to determine if the pre- to posttest change scores on the BASC-2 and BRIEF exceeded what could be accounted for by measurement error alone. Results of the analyses revealed that mindfulness training was effective in increasing the number of on-task behaviors for participants. Parent and teacher ratings on the BRIEF suggest that mindfulness training impacted ratings on the Inhibit, Initiate, and Monitor scales. Parent and teacher ratings on the BASC-2 were analyzed and scores from the Attention Problems scale did not demonstrate significant change across raters and across participants. Significant change occurred on the Hyperactivity scale. Findings are discussed in relationship to the literature on mindfulness training for students with a diagnosis of ADHD. Implications for future research and practice are also suggested. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Attention Deficit / Hyperactivity Disorder (ADHD) is one of the most prevalent childhood disorders in the United States. Although many children with an ADHD diagnosis are prescribed medication to control symptoms, behavioral concerns are still regularly noted in the classroom, home, and other settings. Therefore, school psychologists are often called upon to assist teachers and families with developing intervention procedures. The purpose of this research was to investigate the relationship between mindfulness training, the cognitive processes of attention regulation, and behavior of children who have been diagnosed with ADHD. This study utilized a multiple baseline across participant’s design where each student was tracked over time following a baseline (pre-intervention) condition. Four 8-year-old male participants with a primary diagnosis of ADHD and a significant number of off-task classroom behaviors were included in this study. Teacher and parent ratings of the Behavior Assessment System for Children, Second Edition (BASC-2) and Behavior Rating Inventory of Executive Function (BRIEF) were completed pre- and posttest for each participant. The Reliable Change Index (RCI) was calculated to determine if the pre- to posttest change scores on the BASC-2 and BRIEF exceeded what could be accounted for by measurement error alone. Results of the analyses revealed that mindfulness training was effective in increasing the number of on-task behaviors for participants. Parent and teacher ratings on the BRIEF suggest that mindfulness training impacted ratings on the Inhibit, Initiate, and Monitor scales. Parent and teacher ratings on the BASC-2 were analyzed and scores from the Attention Problems scale did not demonstrate significant change across raters and across participants. Significant change occurred on the Hyperactivity scale. Findings are discussed in relationship to the literature on mindfulness training for students with a diagnosis of ADHD. Implications for future research and practice are also suggested.

The purpose of this study was to determine if brief sessions of imagery had an effect upon concentration style and free throw shooting performance of intercollegiate basketball players. Participants in this study were four current and two former Division I basketball players. A single-subject design was implemented for this investigation (Swain & Jones, 1995; Vernacchia & Cook, 1993; Kendall, Hrycaiko, Martin, & Kendall, 1990). Data collection occurred during the college basketball season to obtain the free throw percentages from actual game situations for the players who were playing. Data for the two players who had finished their college eligibility consisted of previous free throw percentage at the institution. Each participant completed the Basketball Concentration Survey (Bergandi, 1990) (BCS) and the Rockne Free Throw Questionnaire (RFTQ, 1999). The RFTQ is an experimental questionnaire designed to measure self-confidence in free throw shooting. Participants then began shooting free throws three times a week for six weeks. Each session consisted of five warm-up free throws, estimating how many free throws out of 50 would be made, and then shooting 50 free throws. Free throws were shot 10 at a time, with a short break between each 10. A multiple baseline design was used to introduce imagery to each participant in a different week, beginning in week two of the study. Therefore, brief imagery training was utilized for different time periods by five of the six basketball players. Before the first imagery session, imagery was briefly explained to each participant. Each participant was then asked to imagine successfully shooting 10 free throws before shooting the actual 50 free throws. Participants performed the imagery session while standing at the free throw line with their eyes closed with a maximum time limit of five minutes. Once the imagery was introduced to the athlete, the athlete continued to use the imagery before shooting the free throws for the remainder of the study. Prior to beginning the fourth week, each participant again completed the BCS and RFTQ. At the completion of the study, participants completed the BCS and RFTQ for a third time. Each also completed a post-imagery survey concerning their perceived effectiveness of the imagery. Results from this study showed no consistent changes on the BCS subscales. An increase was found with several of the participant's scores on the RFTQ questionnaire. No important increases were found in the free throw shooting. Results did show a high self-efficacy in estimating free throw attempts. All five participants using imagery reported feeling that the imagery helped them, and two participants reported that they would continue to use the imagery.

Volcanic plumes are one of many hazards associated with eruptions. Monitoring helps to mitigate against their effects, understand their environmental and climatic impacts, and interpret volcanic activity. While ground-based measurements are valuable, field campaigns and ground-based instrument networks are expensive and not always viable. Satellite remote sensing is a cost-effective alternative and can be used to track the propagation of plumes as they travel away from the source. This thesis explores some of the ways in which the Infrared Atmospheric Sounding Interferometer (IASI) can be used for this purpose. A method known as CO2 slicing, commonly used to obtain the altitude of meteorological clouds, was adapted for IASI to find the altitude of volcanic ash clouds. The technique was first tested on modelled data, before being successfully applied to scenes containing ash from the Eyjafjallajökull and Grímsvötn eruptions. The second part of this thesis explores how IASI retrievals can be used to monitor volcanic emissions of sulphur dioxide (SO2). A linear retrieval was first applied globally to identify sources of SO2, including emissions from explosive eruptions, non-eruptive degassing and anthropogenic sources. Emissions were commonly identified in Ecuador and Kamchatka and these were explored further with an iterative retrieval which quantified the SO2 amount in each region. The trends observed with IASI were similar to those seen with the Ozone Monitoring Instrument (OMI), and at Tungurahua, good agreement was seen with ground-based flux measurements. The final chapter builds on this research by systematically comparing the upwind and downwind mean column amounts obtained with a linear retrieval at 166 volcanoes. This highlights the strengths and weaknesses of the retrieval and reveals emission trends at some volcanoes; sometimes agreeing well with trends from OMI and in thermal emissions. This simple procedure demonstrates the utility of using IASI for observing changes in volcanic emissions.

The Italian territory is covered of approximately 384,000 ha of coastal lagoons and these could represent potential location for Pacific oyster, Crassostrea gigas (Thunberg, 1793) farming. Approximately 10,000 ha of the coastal Italian lagoons are located in the Sardinian region, these are currently not utilized for shellfish farming, and present suitable environmental conditions that allow for good growth rates and optimal market quality for Pacific oysters farming. Therefore, these lagoons can become potential farming sites to increase this industry in the Italian territory, where the demand for this shellfish species cannot be met by domestic production alone. The aim of this PhD study was to enhance Pacific oyster farming in Mediterranean coastal lagoons taking into account local aquaculture industry’s ambitions and challenges, therefore different Pacific oyster culture aspects were investigated. To achieve the goals of this PhD study, novel farming tools and their benefits to Pacific oyster farming were investigated. Moreover, the validation of ShellSIM® growth model in a new environment was carried out, providing a new validated tool to farmers and stakeholders to monitor oysters’ performances and estimate productivity in local waters. Finally, a site selection methodology was developed to identify suitable sites for Pacific oyster farming, and potential risks to consumers linked to microplastics pollution in coastal areas and uptake in Pacific oyster were investigated. Taken together, the results of this PhD study provide new insight on ways to improve C. gigas sustainable aquaculture industry in Mediterranean coastal lagoons, with particular focus on the Italian territory.

The group of chemicals designated organophosphorus compounds have had a significant impact on modern life, including use as pesticides, industrial plasticizers and chemical warfare agents. Exposure to certain organophosphates produces a delayed degeneration of the longest and largest nerve fibers, including those of the ascending and descending tracts of the spinal cord, a condition termed organophosphorus ester-induced delayed neuropathy (OPIDN). Recorded incidents of such an effect in humans have led to research regarding this neurological disease. Among the OPIDN-inducing agents is mipafox, an organophosphate insecticide, the compound we chose to employ in our studies. Although the hen is the primary experimental model in the safety assessment of organophosphates, current research has suggested that the rat may have some validity as an experimental model. We examined the sequential neuropathic effects of a single dose of mipafox (30mg/kg) in rats and hens on a comparative basis to determine the better experimental model.