83 research outputs found
Detecting Violations of Unidimensionality by Order-Restricted Inference Methods
The assumption of unidimensionality and quantitative measurement represents one of the key concepts underlying most of the commonly applied of item response models. The assumption of unidimensionality is frequently tested although most commonly applied methods have been shown having low power against violations of unidimensionality whereas the assumption of quantitative measurement remains in most of the cases only an (implicit) assumption. On the basis of a simulation study it is shown that order restricted inference methods within a Markov Chain Monte Carlo framework can successfully be used to test both assumptions
Antibody responses to the host-protective Taenia solium oncosphere protein TSOL18 in pigs are directed against conformational epitopes
TSOL18 is a recombinant protein that has been shown in repeated experimental trials to be capable of protecting pigs against challenge infection with the cestode parasite Taenia solium. Antibodies raised by the vaccine are capable of killing the parasite in an in vitroculture and it is believed that antibody and complement-mediated killing of invading parasites is the major protective immune mechanism induced by vaccination with TSOL18. Investigations were undertaken to characterize whether the principal antibody specificities raised by TSOL18 in pigs were against linear or conformational determinants. TSOL18 was expressed in two truncated forms representing either the amino terminal portion or the carboxy terminal portion, with the two truncations overlapping in sequence by 25 amino acids. The original protein (designated TSOL18N−) and the two truncations (TSOL18N−-1 and TSOL18N−-2) were used in inhibition ELISA. TSOL18N− was shown to be capable of completely inhibiting the binding of pig anti-TSOL18N− antibodies to TSOL18N− in ELISA. However, neither TSOL18N−-1 nor TSOL18N−-2, either alone or when combined together, was capable of inhibiting any detectable amount of reactivity of pig anti-TSOL18N− antibodies with TSOL18N−. It is concluded that the dominant antibody specificities, and probably the host-protective specificities, of TSOL18 are conformational epitopes
Monitoring protection against porcine cysticercosis with a monoclonal antibody to conformational epitopes of TSOL18 vaccine
Swimming with captive dolphins: current debates and post-experience dissonance
Dolphins have widespread contemporary appeal and anthropomorphic social representations of dolphins have fuelled a growing desire in tourist populations to seek interaction with them. This paper is concerned with the staged performance of swim-with-dolphin interaction programmes in aquaria. Qualitative interviews with tourists who have swum with captive dolphins identified their immediate recollections and stressed the grace, size and power of dolphins, but also a belief that the experience was too staged, too short and too expensive. Post-purchase dissonance focused on concerns with the size of enclosures and about captivity, too many tricks, limited interpretation and unfulfilled expectations of a quality interaction
The EG95 Antigen of Echinococcus spp. Contains Positively Selected Amino Acids, which May Influence Host Specificity and Vaccine Efficacy
Echinococcosis is a worldwide zoonotic parasitic disease of humans and various herbivorous domestic animals (intermediate hosts) transmitted by the contact with wild and domestic carnivores (definitive hosts), mainly foxes and dogs. Recently, a vaccine was developed showing high levels of protection against one parasite haplotype (G1) of Echinococcus granulosus, and its potential efficacy against distinct parasite variants or species is still unclear. Interestingly, the EG95 vaccine antigen is a secreted glycosylphosphatydilinositol (GPI)-anchored protein containing a fibronectin type III domain, which is ubiquitous in modular proteins involved in cell adhesion. EG95 is highly expressed in oncospheres, the parasite life cycle stage which actively invades the intermediate hosts. After amplifying and sequencing the complete CDS of 57 Echinococcus isolates belonging to 7 distinct species, we uncovered a large amount of genetic variability, which may influence protein folding. Two positively selected sites are outside the vaccine epitopes, but are predicted to alter protein conformation. Moreover, phylogenetic analyses indicate that EG95 isoform evolution is convergent with regard to the number of beta-sheets and alpha-helices. We conclude that having a variety of EG95 isoforms is adaptive for Echinococcus parasites, in terms of their ability to invade different hosts, and we propose that a mixture of isoforms could possibly maximize vaccine efficacy
The 24/7 approach to promoting optimal welfare for captive wild animals
We have an ethical responsibility to provide captive animals with environments that allow them to experience good welfare. Husbandry activities are often scheduled for the convenience of care staff working within the constraints of the facility, rather than considering the biological and psychological requirements of the animals themselves. The animal welfare 24/7 across the lifespan concept provides a holistic framework to map features of the animal’s life cycle, taking into account their natural history, in relation to variations in the captive environment, across day and night, weekdays, weekends, and seasons. In order for animals to have the opportunity to thrive, we argue the need to consider their lifetime experience, integrated into the environments we provide, and with their perspective in mind. Here, we propose a welfare assessment tool based upon 14 criteria, to allow care staff to determine if their animals’ welfare needs are met. We conclude that animal habitat management will be enhanced with the use of integrated technologies that provide the animals with more opportunities to engineer their own environments, providing them with complexity, choice and control
Psychopathology of addiction: Can the SCL90-based five-dimensional structure differentiate Heroin Use Disorder from a non-substance-related addictive disorder such as Gambling Disorder?
The behaviour and vocalisations of common dolphins Delphinus delphis at Marineland, Napier, New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Zoology at Massey University
Three female common dolphins Delphinus delphis at Marineland, Napier were studied from November 1998, through to October 1999. The first step was to construct an ethogram. Following that, I examined the behavioural and vocal responses of the dolphins to the Swim-with-Dolphin (SWD) programme. An ethogram was constructed for common dolphin behaviour by collating notes and video footage. The ethogram consists of 16 categories of behaviour that were subdivided into different aspects of those behaviours. Each behaviour is described and some are illustrated. The effect of the SWD programme was assessed by monitoring changes in the dolphins use of a refuge area, changes in six behavioural categories (Aggressive, Touch, Other, Abrupt, Submissive and Play), and changes in surfacing frequency and location before, during and after SWD sessions. There was a significant increase in refuge area use during a SWD session, but this returned to pre-swim levels immediately afterwards. There were small changes in behaviour during SWD sessions, with an increase in Other and Touch behaviours. These changes are not like the documented stress response of bottlenose dolphins Tursiops truncatus which include an increase in aggression. During sessions with swimmers the frequency of surfacing increased slightly and a greater percentage of surfacing occurred in the refuge area. The difference in the proportion of five types of dolphin vocalisations (Whistles, Clicks, Chirps, Squeaks and Whines) before, during and after SWD sessions was not significant. There was a slight increase in the frequency of all calls during SWD sessions. The behaviour that occurred during 521 vocalisations was also analyzed. Clicks were commonly heard when the dolphins were approaching people, another dolphin or the bell. Chirps indicated the departure of one dolphin from the other. The common dolphins at Marineland show no significant behaviours indicative of distress in response to the SWD programme. The behaviour changes that occurred were not associated with a distress response and the changes in vocalisations were not significant
Three theories of psychological measurement in the assessment of subjective control in gambling behaviour
The aim of this study was to argue for a new conception of subjective control and then to devise psychometric scales to test this new conception in the area of gambling behaviour. The 'Subjective Control'scales were constructed using Michell's (1994a, 1998) theory of the ordinal determinable. After extensive pilot testing, these scales were administered to a participant sample consisting of 57 students, 104 in situ club EGM players and 49 self-referred problem gamblers. The data collected consisted of paired comparisons judgements, ratings and rank orders. The limitations of the findings were discussed and suggestions for future research were made
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