Nuclear phenotype changes after heat shock in Panstrongylus megistus (Burmeister)

The nuclear phenotypes of Malpighian tubule epithelial cells of male nymphs of the blood-sucking insect, Panstrongylus megistus, subjected to short- and long-duration heat shocks at 40ºC were analyzed immediately after the shock and 10 and 30 days later. Normal nuclei with a usual heterochromatic body as well as phenotypes indicative of survival (unravelled heterochromatin, giants) and death (apoptosis, necrosis) responses were observed in control and treated specimens. However, all nuclear phenotypes, except the normal ones, were more frequent in shocked specimens. Similarly altered phenotypes have also been reported in Triatoma infestans following heat shock, although at different frequencies. The frequency of the various nuclear phenotypes observed in this study suggests that the forms of cell survival observed were not sufficient or efficient enough to protect all of the Malpighian tubule cells from the deleterious effects of stress. In agreement with studies on P. megistus survival following heat shock, only long-duration shock produced strongly deleterious effects.

Degree in Social Work Incentive Scheme 2006 (PDF 45 KB)

Student Bursaries Incentive Scheme

Persistence of a Gastrocutaneous Fistula after gastrostomy removal in children: Incidence and predictive factors

Background/Purpose: The aims of this study were to determine the incidence of persistent gastrocutaneous fistulas (GCF) after gastrostomy removal and to identify associated risk factors. Methods: This retrospective study included 75 children from the Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland who had a gastrostomy performed between 1988 and 2010. The records of the children were reviewed for sex, age at the time of gastrostomy removal, underlying disease, type of gastrostomy placement and length of use, and then analyzed in order to find a correlation between the GCF and these parameters. Results: The gastrostomy orifice did not close spontaneously within the first month in 33 of the patients (44%), and 15 subsequently underwent surgical closure. The mean duration of gastrostomy use was significantly longer in children who developed a persistent GCF (30 vs. 19 months, P = 0.03). The other parameters studied did not show any significant association with the persistence of a GCF. Conclusions: The only predictive factor determining the persistence of a GCF was found to be the timespan between the placement and removal of the gastrostomy appliance. Elective surgical closure of the gastrostomy orifice should be considered after 1 month of persistent GCF.

Review of the Diploma in Social Work (JM Consulting Report) (PDF 97 KB)

Review of the Diploma in Social Work (JM Consulting Report)

Northern Ireland Framework Specification for the Degree in Social Work (PDF 213 KB)

Northern Ireland Framework Specification for the Degree in Social Work

New perspectives in the use of ink evidence in forensic science

Resume : L'utilisation de l'encre comme indice en sciences forensiques est décrite et encadrée par une littérature abondante, comprenant entre autres deux standards de l'American Society for Testing and Materials (ASTM). La grande majorité de cette littérature se préoccupe de l'analyse des caractéristiques physiques ou chimiques des encres. Les standards ASTM proposent quelques principes de base qui concernent la comparaison et l'interprétation de la valeur d'indice des encres en sciences forensiques. L'étude de cette littérature et plus particulièrement des standards ASTM, en ayant a l'esprit les développements intervenus dans le domaine de l'interprétation de l'indice forensique, montre qu'il existe un potentiel certain pour l'amélioration de l'utilisation de l'indice encre et de son impact dans l'enquête criminelle. Cette thèse propose d'interpréter l'indice encre en se basant sur le cadre défini par le théorème de Bayes. Cette proposition a nécessité le développement d'un système d'assurance qualité pour l'analyse et la comparaison d'échantillons d'encre. Ce système d'assurance qualité tire parti d'un cadre théorique nouvellement défini. La méthodologie qui est proposée dans ce travail a été testée de manière compréhensive, en tirant parti d'un set de données spécialement créer pour l'occasion et d'outils importés de la biométrie. Cette recherche répond de manière convaincante à un problème concret généralement rencontré en sciences forensiques. L'information fournie par le criminaliste, lors de l'examen de traces, est souvent bridée, car celui-ci essaie de répondre à la mauvaise question. L'utilisation d'un cadre théorique explicite qui définit et formalise le goal de l'examen criminaliste, permet de déterminer les besoins technologiques et en matière de données. Le développement de cette technologie et la collection des données pertinentes peut être justifiées économiquement et achevée de manière scientifique. Abstract : The contribution of ink evidence to forensic science is described and supported by an abundant literature and by two standards from the American Society for Testing and Materials (ASTM). The vast majority of the available literature is concerned with the physical and chemical analysis of ink evidence. The relevant ASTM standards mention some principles regarding the comparison of pairs of ink samples and the evaluation of their evidential value. The review of this literature and, more specifically, of the ASTM standards in the light of recent developments in the interpretation of forensic evidence has shown some potential improvements, which would maximise the benefits of the use of ink evidence in forensic science. This thesis proposes to interpret ink evidence using the widely accepted and recommended Bayesian theorem. This proposition has required the development of a new quality assurance process for the analysis and comparison of ink samples, as well as of the definition of a theoretical framework for ink evidence. The proposed technology has been extensively tested using a large dataset of ink samples and state of the art tools, commonly used in biometry. Overall, this research successfully answers to a concrete problem generally encountered in forensic science, where scientists tend to self-limit the usefulness of the information that is present in various types of evidence, by trying to answer to the wrong questions. The declaration of an explicit framework, which defines and formalises their goals and expected contributions to the criminal and civil justice system, enables the determination of their needs in terms of technology and data. The development of this technology and the collection of the data is then justified economically, structured scientifically and can be proceeded efficiently.

A Strategy for Health & Social Care Research and Development in Northern Ireland

The Department of Health, Social Services and Public Safety (DHSSPS) is seeking your views on a A Strategy for Health & Social Care Research and Development in Northern Ireland Allowing for public holidays, the draft Strategy has been issued for a 13 week consultation period from 29 September 2014. åÊResponses must be received no later than 5pm on Friday 2 January 2015

Role of genetic and social factors in modulating the efficiency of division of labour in social insects

Summary : Division of labour is one of the most fascinating aspects of social insects. The efficient allocation of individuals to a multitude of different tasks requires a dynamic adjustment in response to the demands of a changing environment. A considerable number of theoretical models have focussed on identifying the mechanisms allowing colonies to perform efficient task allocation. The large majority of these models are built on the observation that individuals in a colony vary in their propensity (response threshold) to perform different tasks. Since individuals with a low threshold for a given task stimulus are more likely to perform that task than individuals with a high threshold, infra-colony variation in individual thresholds results in colony division of labour. These theoretical models suggest that variation in individual thresholds is affected by the within-colony genetic diversity. However, the models have not considered the genetic architecture underlying the individual response thresholds. This is important because a better understanding of division of labour requires determining how genotypic variation relates to differences in infra-colony response threshold distributions. In this thesis, we investigated the combined influence on task allocation efficiency of both, the within-colony genetic variability (stemming from variation in the number of matings by queens) and the number of genes underlying the response thresholds. We used an agent-based simulator to model a situation where workers in a colony had to perform either a regulatory task (where the amount of a given food item in the colony had to be maintained within predefined bounds) or a foraging task (where the quantity of a second type of food item collected had to be the highest possible). The performance of colonies was a function of workers being able to perform both tasks efficiently. To study the effect of within-colony genetic diversity, we compared the performance of colonies with queens mated with varying number of males. On the other hand, the influence of genetic architecture was investigated by varying the number of loci underlying the response threshold of the foraging and regulatory tasks. Artificial evolution was used to evolve the allelic values underlying the tasks thresholds. The results revealed that multiple matings always translated into higher colony performance, whatever the number of loci encoding the thresholds of the regulatory and foraging tasks. However, the beneficial effect of additional matings was particularly important when the genetic architecture of queens comprised one or few genes for the foraging task's threshold. By contrast, higher number of genes encoding the foraging task reduced colony performance with the detrimental effect being stronger when queens had mated with several males. Finally, the number of genes determining the threshold for the regulatory task only had a minor but incremental effect on colony performance. Overall, our numerical experiments indicate the importance of considering the effects of queen mating frequency, genetic architecture underlying task thresholds and the type of task performed when investigating the factors regulating the efficiency of division of labour in social insects. In this thesis we also investigate the task allocation efficiency of response threshold models and compare them with neural networks. While response threshold models are widely used amongst theoretical biologists interested in division of labour in social insects, our simulation reveals that they perform poorly compared to a neural network model. A major shortcoming of response thresholds is that they fail at one of the most crucial requirement of division of labour, the ability of individuals in a colony to efficiently switch between tasks under varying environmental conditions. Moreover, the intrinsic properties of the threshold models are that they lead to a large proportion of idle workers. Our results highlight these limitations of the response threshold models and provide an adequate substitute. Altogether, the experiments presented in this thesis provide novel contributions to the understanding of how division of labour in social insects is influenced by queen mating frequency and genetic architecture underlying worker task thresholds. Moreover, the thesis also provides a novel model of the mechanisms underlying worker task allocation that maybe more generally applicable than the widely used response threshold models. Resumé : La répartition du travail est l'un des aspects les plus fascinants des insectes vivant en société. Une allocation efficace de la multitude de différentes tâches entre individus demande un ajustement dynamique afin de répondre aux exigences d'un environnement en constant changement. Un nombre considérable de modèles théoriques se sont attachés à identifier les mécanismes permettant aux colonies d'effectuer une allocation efficace des tâches. La grande majorité des ces modèles sont basés sur le constat que les individus d'une même colonie diffèrent dans leur propension (inclination à répondre) à effectuer différentes tâches. Etant donné que les individus possédant un faible seuil de réponse à un stimulus associé à une tâche donnée sont plus disposés à effectuer cette dernière que les individus possédant un seuil élevé, les différences de seuils parmi les individus vivant au sein d'une même colonie mènent à une certaine répartition du travail. Ces modèles théoriques suggèrent que la variation des seuils des individus est affectée par la diversité génétique propre à la colonie. Cependant, ces modèles ne considèrent pas la structure génétique qui est à la base des seuils de réponse individuels. Ceci est très important car une meilleure compréhension de la répartition du travail requière de déterminer de quelle manière les variations génotypiques sont associées aux différentes distributions de seuils de réponse à l'intérieur d'une même colonie. Dans le cadre de cette thèse, nous étudions l'influence combinée de la variabilité génétique d'une colonie (qui prend son origine dans la variation du nombre d'accouplements des reines) avec le nombre de gènes supportant les seuils de réponse, vis-à-vis de la performance de l'allocation des tâches. Nous avons utilisé un simulateur basé sur des agents pour modéliser une situation où les travailleurs d'une colonie devaient accomplir une tâche de régulation (1a quantité d'une nourriture donnée doit être maintenue à l'intérieur d'un certain intervalle) ou une tâche de recherche de nourriture (la quantité d'une certaine nourriture doit être accumulée autant que possible). Dans ce contexte, 'efficacité des colonies tient en partie des travailleurs qui sont capable d'effectuer les deux tâches de manière efficace. Pour étudier l'effet de la diversité génétique d'une colonie, nous comparons l'efficacité des colonies possédant des reines qui s'accouplent avec un nombre variant de mâles. D'autre part, l'influence de la structure génétique a été étudiée en variant le nombre de loci à la base du seuil de réponse des deux tâches de régulation et de recherche de nourriture. Une évolution artificielle a été réalisée pour évoluer les valeurs alléliques qui sont à l'origine de ces seuils de réponse. Les résultats ont révélé que de nombreux accouplements se traduisaient toujours en une plus grande performance de la colonie, quelque soit le nombre de loci encodant les seuils des tâches de régulation et de recherche de nourriture. Cependant, les effets bénéfiques d'accouplements additionnels ont été particulièrement important lorsque la structure génétique des reines comprenait un ou quelques gènes pour le seuil de réponse pour la tâche de recherche de nourriture. D'autre part, un nombre plus élevé de gènes encodant la tâche de recherche de nourriture a diminué la performance de la colonie avec un effet nuisible d'autant plus fort lorsque les reines s'accouplent avec plusieurs mâles. Finalement, le nombre de gènes déterminant le seuil pour la tâche de régulation eu seulement un effet mineur mais incrémental sur la performance de la colonie. Pour conclure, nos expériences numériques révèlent l'importance de considérer les effets associés à la fréquence d'accouplement des reines, à la structure génétique qui est à l'origine des seuils de réponse pour les tâches ainsi qu'au type de tâche effectué au moment d'étudier les facteurs qui régulent l'efficacité de la répartition du travail chez les insectes vivant en communauté. Dans cette thèse, nous étudions l'efficacité de l'allocation des tâches des modèles prenant en compte des seuils de réponses, et les comparons à des réseaux de neurones. Alors que les modèles basés sur des seuils de réponse sont couramment utilisés parmi les biologistes intéressés par la répartition des tâches chez les insectes vivant en société, notre simulation montre qu'ils se révèlent peu efficace comparé à un modèle faisant usage de réseaux de neurones. Un point faible majeur des seuils de réponse est qu'ils échouent sur un point crucial nécessaire à la répartition des tâches, la capacité des individus d'une colonie à commuter efficacement entre des tâches soumises à des conditions environnementales changeantes. De plus, les propriétés intrinsèques des modèles basés sur l'utilisation de seuils conduisent à de larges populations de travailleurs inactifs. Nos résultats mettent en évidence les limites de ces modèles basés sur l'utilisation de seuils et fournissent un substitut adéquat. Ensemble, les expériences présentées dans cette thèse fournissent de nouvelles contributions pour comprendre comment la répartition du travail chez les insectes vivant en société est influencée par la fréquence d'accouplements des reines ainsi que par la structure génétique qui est à l'origine, pour un travailleur, du seuil de réponse pour une tâche. De plus, cette thèse fournit également un nouveau modèle décrivant les mécanismes qui sont à l'origine de l'allocation des tâches entre travailleurs, mécanismes qui peuvent être appliqué de manière plus générale que ceux couramment utilisés et basés sur des seuils de réponse.

Strategy for personal and public involvement in Health and Social Care research

This report outlines the strategic need for, and benefits of, personal and public involvement to all levels of Health and Social Care Research and Development Division activity.

Task-dependent influence of genetic architecture and mating frequency on division of labour in social insect societies.

Division of labour is one of the most prominent features of social insects. The efficient allocation of individuals to different tasks requires dynamic adjustment in response to environmental perturbations. Theoretical models suggest that the colony-level flexibility in responding to external changes and internal perturbation may depend on the within-colony genetic diversity, which is affected by the number of breeding individuals. However, these models have not considered the genetic architecture underlying the propensity of workers to perform the various tasks. Here, we investigated how both within-colony genetic variability (stemming from variation in the number of matings by queens) and the number of genes influencing the stimulus (threshold) for a given task at which workers begin to perform that task jointly influence task allocation efficiency. We used a numerical agent-based model to investigate the situation where workers had to perform either a regulatory task or a foraging task. One hundred generations of artificial selection in populations consisting of 500 colonies revealed that an increased number of matings always improved colony performance, whatever the number of loci encoding the thresholds of the regulatory and foraging tasks. However, the beneficial effect of additional matings was particularly important when the genetic architecture of queens comprised one or a few genes for the foraging task's threshold. By contrast, a higher number of genes encoding the foraging task reduced colony performance with the detrimental effect being stronger when queens had mated with several males. Finally, the number of genes encoding the threshold for the regulatory task only had a minor effect on colony performance. Overall, our numerical experiments support the importance of mating frequency on efficiency of division of labour and also reveal complex interactions between the number of matings and genetic architecture.

Systematic review and meta-analysis of risk factors for survival after lung metastasectomy in colorectal cancer patients

Objective: Resection of lung metastases (LM) from colorectal cancer (CRC)¦is increasingly performed with a curative intent.Most series report small groups¦of patients, and it is currently not possible to identify those CRC patients who¦may benefit the most of surgical management. It is clinically relevant to assess¦risk factors for prolonged survival after this type of procedures.¦Methods: A meta analysis of 24 series published between 2000 and 2011¦which focused on surgical management of LM from CRC and included more¦than 40 patients each, with or without prior resection of in transit liver¦metastases. Random effects were calculated for five variables considered as¦potential prognostic factors.¦Results: A total of 2815 patients who underwent surgery with a curative¦intent were considered in this analysis. Four parameters were associated with¦a decreased survival: 1) a short disease-free interval between primary tumor¦resection and development of LM (HR = 1·59, 95% CI 1·27-1·98); 2) multiple¦LM (HR = 2·04, 95%CI 1·72-2·41); 3) positive hilar/mediastinal lymph nodes¦(HR = 1·65, 95% CI 1·35-2·02); and 4) a high prethoracotomy CEA value (HR¦=1·91, 95% CI 1·57-2·32). By comparison, a history of resected liver metastases¦(HR = 1·36, 95% CI 0·92-2·03) did not achieve statistical significance.¦Conclusion: Risk factors for poor clinical outcome after surgery for lung¦metastases in CRC patients include: 1) synchronous lung metastases; 2) high¦pre-thoracotomy CEA; 3) hilar nodes involvement; and 4) multiple pulmonary¦lesions.