NUI Maynooth Eprint Archive
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A molecular and cellular characterisation of the effects of neonicotinoid pesticides on the brain of the pollinator Bombus terrestris.
No full textBombus terrestris (L.) is one of the most important native and commercial pollinator species worldwide. Along with other pollinators their populations are in decline due to a multifactorial phenomenon that includes the extensive use of neonicotinoid insecticides. Thus, the characterisation and understanding of neonicotinoid effects on bees at the molecular level is essential to mitigate the risks of their use in the environment. This study initially characterised the brain proteomes of bumblebees in response to aging prior to assessing changes at the behavioural, cellular and molecular level as a response to neonicotinoid exposure. We demonstrated the highly catalytic nature of the developing bumblebee brain and how energy and carbohydrate metabolism increase in response to aging, while genetic information processes are downregulated. By considering differences in mode of action and mode of exposure to the neonicotinoids clothianidin and imidacloprid, the effects of acute and chronic oral exposure on bumblebee workers were determined. Neonicotinoids differentially impair energy metabolism and structural processes in the brain suggesting possible divergence of insecticide mode of action. Clothianidin and imidacloprid triggered different behavioural responses and toxicity in bees, with the former causing hyperactivity and the latter, temporal paralysis. Imidacloprid is less toxic to bumblebees and the brain physiology is differentially affected depending on chemical, dose or mode of exposure selected. The levels of the synapse associated protein synapsin increased in bumblebee brains for imidacloprid-exposed bees only, and functional annotation analysis of differential expressed proteins indicated impairment of intracellular transport, energy metabolism, translational activity, purines and pyrimidines metabolism, endocytic and exocytic activity and synaptic functioning as a whole. The pathways affected by neonicotinoid exposure vary depending on chemical and mode of exposure, which complicates the identification of biomarkers of neonicotinoid exposure in bumblebees. In addition, neonicotinoid metabolism in bees is poorly understood and these chemicals can accumulate in the bee body, which potentially contributes to long term toxicity. Overall the results presented in this thesis demonstrate individual and distinct ways by which neonicotinoids influence neuronal communication and provide novel insights into molecular aspects of bee health, through highlighting the pathways affected by aging and pesticide use on this important pollinator species
Enhancing the effect of quantum many-body scars on dynamics by minimizing the effective dimension
No full textQuantum many-body scarring is believed to be the mechanism behind long-lived coherent oscillations in interacting Rydberg atom chains. These persistent oscillations are due to the large overlap of the many-body scars with certain initial states. We show that the “effective dimension” is a useful measure for identifying nonthermalizing initial states in many-body scarred systems. By minimising the effective dimension we find physically reasonable initial states of the Rydberg chain that lead to more pronounced and longer-lived oscillations, accentuating the effect of the many-body scars on the dynamics
Workplace issues in the context of Aldous Huxley’s Brave New World: Mental health problems, cannabis and the division of labour.
No full textThis paper examines the distinctive value of literature inside organisational theory, and howusing narratives as possible future scenarios can help both academics and managers considerthe consequences of mental health problems, the (mis)use of drugs, and the division of labourin the workplace. The paper adopts Aldous Huxley’s novelBrave New Worldfor this purpose.Another contribution of the paper is providing a model that offers managers a step-by-stepaction plan of how to use literary texts to study sensitive workplace issues, generating newknowledge which would ultimately help them to envision ways to act appropriately anddevelop future strategies
The roles played by boards of directors: an integration of the agency and stakeholder theories.
No full textThis paper explores the development and articulation of the agency and stakeholder theories ofthe firm and their corresponding logics of shareholder wealth maximisation and stakeholderinterest optimisation. We note how these two perspectives have been viewed as diametricallyopposite normative, instrumental and descriptive theories, despite efforts by some authors tofind common ground. Each has served as a basis for firm governance. We explore the relation-ship of the agency and stakeholder theories to the conceptualisations of the roles of boards ofdirectors, and how both theories hold value in understanding two board function
Relationships, reciprocity and reflective practice in challenging times
No full textThe abstract is included in the text
Complementary Protection and Encampment
No full textA camp may be described as a temporary space in which individuals receive humanitarian
relief and protection until a durable solution can be found to their situation. The camp
environment is often riddled with contradictions—the camp can be a place of refuge while
at the same time, a place of overcrowding, exclusion and suffering. This article asks to
what extent removal of an individual from state A to state B, where he or she will have to
live in a camp, is a breach of state A’s human rights law obligations. It argues that even if
encampment in state B will expose the individual to terrible conditions, it is unlikely that
they will be able to successfully challenge a removal decision before international human
rights courts and/or treaty monitoring bodies
Exploring problem conceptualization and performance in STEM problem solving contexts
No full textProblem solving abilities are critical components of contemporary Science, Technology,
Engineering and Mathematics (STEM) education. Research in the area of problem solving
has uncovered much about the representation, processes and heuristic approaches to problem solving. However, critics claim this overemphasis on the process of solving problems
has led to a dearth in understanding of the earlier stages such as problem conceptualization.
This paper aims to address some of these concerns by exploring the area of problem conceptualization and the underlying cognitive mechanisms that may play a supporting role in
reasoning success. Participants (N=12) were prescribed a series of convergent problemsolving tasks representative of those used for developmental purposes in STEM education. During the problem-solving episodes, cognitive data were gathered by means of an
electroencephalographic headset and used to investigate students’ cognitive approaches to
conceptualizing the tasks. In addition, interpretive qualitative data in the form of post-task
interviews and problem solutions were collected and analyzed. Overall findings indicated
a significant reliance on memory during the conceptualization of the convergent problem solving tasks. In addition, visuospatial cognitive processes were found to support the conceptualization of convergent problem-solving tasks. Visuospatial cognitive processes facilitated students during the conceptualization of convergent problems by allowing access to
diferential semantic content in long-term memor
Algebraic Method for the Reconstruction of Partially Observed Nonlinear Systems Using Differential and Integral Embedding
No full textThe identification of partially observed continuous nonlinear systems from noisy and incomplete data series is an actual problem in many branches of science, for example, biology, chemistry, physics, and others. Two stages are needed to reconstruct a partially observed dynamical system. First, one should reconstruct the entire phase space to restore unobserved state variables. For this purpose, the integration or differentiation of the observed data series can be performed. Then, a fast-algebraic method can be used to obtain a nonlinear system in the form of a polynomial dynamical system. In this paper, we extend the algebraic method proposed by Kera and Hasegawa to Laurent polynomials which contain negative powers of variables, unlike ordinary polynomials. We provide a theoretical basis and experimental evidence that the integration of a data series can give more accurate results than the widely used differentiation. With this technique, we reconstruct Lorenz attractor from a one-dimensional data series and B. Muthuswamy’s circuit equations from a three-dimensional data series
Blended to Online Learning during the COVID-19 Pandemic: A Case Study of Practice
No full textA synergetic partnership of the Maynooth University Department of Adult and Community Education and the Further Education Support Services identified an educational need among Further Education and Training (FET) staff. The outcome was a jointly developed and delivered Level 9 blended learning Postgraduate Certificate in Programme Design and Validation in Further Education and
Training (PGPDV). The delivery of the pilot course was significantly challenged by COVID-19’s sudden arrival in March 2020, forcing the course fully online. This
article gathers feedback on lessons learned and offers practical steps to guide adult educators in pivoting courses for online delivery
Temperature as a Chaotic Circuit Bifurcation Parameter
No full textThe number of researches aimed at understanding the chaotic behavior of nonlinear dynamical systems has grown considerably in recent years. The development of electronic circuits that exhibit this type of behavior has been the interest of numerous works in the literature. Among the possible sets of nonlinear systems, the simplest in which one can observe bifurcation phenomena and chaotic behavior, followed by well– controlled experiments, are nonlinear electronic circuits. One of the most widely used tools for analysis and evaluation of chaotic behavior is known as the bifurcation diagram. Generally, in the analysis of these circuits, parameters such as voltage, current and frequency are used to verify their respective behaviors. Variable values of passive components such as resistors and capacitors are also widely used. The temperature has also been used as a bifurcation parameter in resistor, diode and inductor (RLD) circuits. However, there is little attention from the scientific community on temperature as a bifurcation parameter for electronic circuits using operational amplifiers such as the chaotic Jerk circuit. In this sense, this project aims to implement a chaotic Jerk circuit, composed of operational amplifiers, resistors and capacitors, and subject it to different temperature levels, using this variable as an analysis parameter. Thus, at the end of this work it was possible to verify that the temperature variation directly influences the behavior of the investigated system, thus reaching the final objective of the project, presenting that the temperature can be a bifurcation parameter for a chaotic Jerk circuit