VictorJuiz/thesis huggingface dataset:
Working memory in healthy ageing
Keywords: emotion
individual differences
functional magnetic resonance imaging
ageing
neuroscience
Working memory
magnetoencephalography
psychology
cognition

This thesis is concerned with the age-related changes in working memory (WM), and the inter-individual differences in cognitive and neural mechanisms that correspond to healthy versus poor ageing of WM function. The first half of this thesis focusses on the age-related decline in WM and whether preserved top-down attentional control could mitigate such deficits. In Chapter 2, I present a functional MRI study showing that older adults reliably recruit brain networks that subserve cognitive control, which work in concert with the task relevant sensory areas during effective selective WM. In Chapter 3, I show that older adults retain flexible control over WM representations, and this ability corresponded to the reliable recruitment of neural signals of orienting attention qualitatively similar to those observed in younger adults. Magnetoencephalographic recordings showed that the neural dynamics during orienting attention within WM was predictive of good performance, demonstrating that the more efficient the process of orienting within WM to select the target item, the better the memory representation can be preserved for upcoming behaviour. In the second half of this thesis, I explored whether WM for affective content has a special status in healthy ageing. In Chapter 4, I developed an emotional WM precision task to measure WM abilities for emotional content appropriate for elderly adults. In Chapter 5, I tested a group of young and older adults on WM and perceptual-matching abilities for emotional faces. The results suggest that older adults show a general impairment in task performance, but possibly with some preservation in the ability to maintain emotional content in WM. There were marked differences in how the emotional information was processed between age groups, in which older adults have a tendency to represent negative stimuli as less negative than younger adults in perception and WM, and tended to show a positive interpretation of the valence of more ambiguous emotional stimuli. In Chapter 6, I summarise the findings presented in this thesis, discuss the implications of the key findings, and consider some suggestions for future studies that aim to elucidate the mechanisms of WM in healthy ageing.
A study of the reactivity and coordination chemistry of N-heterocyclic carbenes with main group compounds
Keywords: Ditopic
Silicon
N-Heterocyclic carbene
Lead
Low valent
Phosphorus
Tin
Arsenic
Germanium

This thesis describes selected reactivity studies of the N-heterocyclic carbene, IPr, towards a range of main group compounds. The synthesis and characterisation of sixty-three compounds, all of which incorporate IPr as a ligand in one of three coordination modes, are detailed herein.
The deprotonation of IPr allowed for the isolation of an anionic source of the aIPr: ligand which was synthesised as a novel potassium salt and along with the previously reported lithium salt, was employed in reactions with group 12 and 14 bis(trimethylsilyl)amides and tetrahalides. The further chemistry of such novel products was investigated towards both electrophilic and nucleophilic reagents making use of both the pendant nucleophilic carbene functionality and the electrophilic main group centre.
An alternative route to such species was investigated by the spontaneous isomerisation of IPr in the coordination sphere of group 14 tetrabromides and group 15 tribromides. The scope of this reactivity was subsequently investigated and was found to provide a simpler route to access the abnormal coordination mode of IPr. The aIPr ligand which is generated may be deprotonated by additional IPr thereby affording aIPr: ligands. The addition of halide abstracting agents allowed for the synthesis of cationic species stabilised by the coordination of either IPr or aIPr ligands.
A unique, spontaneous reductive coupling of two phosphorus centres was discovered to take place upon heating a THF solution of (IPr)PBr3. This allowed for the isolation of a bromide bridged P–P bond with reduced phosphorus centres. This facile reduction chemistry was further explored by reaction with mild reducing agents which provide access to low oxidation state phosphorus compounds in high yields. This chemistry was found to be possible (and more effective) due to the presence of the weaker phosphorus bond to bromine relative to the commonly employed chlorine ligands.
Playing different games: West African and European perspectives on negotiating economic partnership agreements
Keywords: Negotiations
EU-Africa cooperation
game theory
International Relations
global trade
constructivism
strategic interaction

This thesis examines the reasons for persistent impasses encountered in the negotiations to achieve so-called ‘Economic Partnership Agreements’ between the EU and West Africa by drawing on the analysis of strategic interaction. I argue that in order to fully understand the failure to reach an agreement during more than eight years of negotiations we need to go beyond conventional rationalist approaches that rely on game-theoretical insights. Instead of presuming that the so-called ‘rules of the game’ are common knowledge among the actors, I conceive of bargaining processes as a space to (re)negotiate the ‘games’ played by states in the first place. To systematise how disagreement at the level of the rules of the game affects strategic interaction and the cooperation issues faced by states, the thesis introduces the conceptual model of a ‘Battle over Games’. Such a constructivist-informed approach relates the choice of ‘sub-optimal’ bargaining strategies to the possibility of divergent interpretations of the rules rather than a lack of information. Moreover, it sees identity-based conflicts around values and beliefs rather than merely functional collective action problems as important obstacles to cooperation. I argue that divergent normative convictions about which ‘game’ ought to be played can lead to a hardening of negotiating positions that prolongs impasse situations. The main empirical argument presented is that different understandings about the rules of the game operative in trade negotiations with a ‘development dimension’ underpinned the cooperation partners’ inability and unwillingness to reconcile their conflicting interests. Examining two different negotiating periods (2002-2007 and 2008-2010) allows us to assess how the emergence and persistence of the impasse can be understood through the lens of the actors’ subjectively different understandings of the ‘game’ they were playing. I, firstly, argue that the EU and the West African side’s ill-conceived strategy choices in the first negotiating period were related to the divergent interpretations of the development framing of the trade negotiations. Secondly, I develop the argument that the persistence of opposing positions was ultimately sustained by a value conflict over whether to pursue procedural or substantive equality in these trade negotiations, and divergent beliefs about how best to foster economic development. The thesis concludes with a summary of the research findings.
Patrons and artists at the crossroads: the Islamic arts of the book in the lands of Rūm, 1270s-1370s
Keywords: Manuscripts
Rūm
Konya
Calligraphy
Codicology
Erzincan
Illumination
Anatolia
Mevlevis
Beyliks

This dissertation is the first book-length study to analyse the production and patronage of Islamic illuminated manuscripts in late medieval Rūm in their fullest cultural contexts and in relation to the arts of the book of neighbouring regions. Although research concerning the artistic landscapes of late medieval Rūm has made significant progress in recent years, the development of the arts of the book and the nature of their patronage and production has yet to be fully addressed. The topic also remains relatively neglected in the wider field of Islamic art history. This thesis considers the arts of the book and the part they played in artistic life within contemporary scholarly frameworks that emphasise inclusivity, diversity and fluidity. Such frameworks acknowledge the period’s ethnic and religious pluralism, the extent of cross-cultural exchange, the region’s complex political situation after the breakdown in Seljuk rule, and the itinerancy of scholars, Sufis and craftsmen.
Analyses are based on the codicological examination of sixteen illuminated Persian and Arabic manuscripts, none of which have been published in depth. In order to appropriately assess the material and to partially redress scholarly emphases on the constituent arts of the book (calligraphy, illumination, illustration and binding), the manuscripts are considered as whole objects. The manuscripts’ ample inscriptions also help to form a clearer picture of contemporary artistic life. Evidence from further illuminated and non-illuminated manuscripts and other textual and material primary sources is also examined.
Based on this evidence, this dissertation demonstrates that Rūm’s towns had active cultural scenes despite the frequent outbreak of hostilities and the absence of an effective centralised government. The lavishness of some manuscripts from this period also challenges the often-assumed connection between dynastic patronage and sophisticated artistic production. Furthermore, the identities and affiliations of those involved in the production and patronage of illuminated manuscripts reinforces the impression of an ethnically and religiously diverse environment and highlights the role that local amīrs and Sufi dervishes in particular had in the creation of such material.
Reactivation and reinstatement of hippocampal assemblies
Keywords: Memory consolidation
Hippocampus
Cell assemblies
Reactivation
Sharp-wave ripples (SWRs)

New memories are labile, but over time some of them are stabilized. This thesis investigates the network mechanisms in the brain underlying the gradual consolidation of memory representations. Specifically, I performed a causal test of the long-standing hypothesis that the offline reactivation of new, memory-representing cell assemblies supports memory consolidation by stabilizing those assemblies and increasing the likelihood of their later reinstatement—and therefore presumably of memory recall.
I performed multi-unit extracellular recordings in the dorsal CA1 region of behaving mice, from which I detected short-timescale (25 ms) co-activation patterns of principal neurons during exploration of open-field enclosures. These cell assembly patterns appeared to represent space as their expression was spatially tuned and environment specific; and these patterns were preferentially reactivated during sharp wave-ripples (SWRs) in subsequent sleep. Importantly, after exposure to a novel—but not a familiar—enclosure, the strength with which an assembly pattern was reactivated predicted its later reinstatement strength during context re-exposure. Moreover, optogenetic silencing of hippocampal pyramidal neurons during on-the-fly detected SWRs during the sleep following exposure to a novel—but again not a familiar—enclosure impaired subsequent assembly pattern reinstatement. These results are direct evidence for a causal role of SWR-associated reactivation in the stability of new hippocampal cell assemblies.
Surprisingly, offline reactivation was only important for the stability of a subset of the assembly patterns expressed in a novel enclosure. Optogenetic SWR silencing only impaired the reinstatement of "gradually strengthened" patterns that had had a significant increasing trend in their expression strength throughout the initial exposure session. Consistent with this result, a positive correlation between reactivation and subsequent reinstatement was only found for these gradually strengthened patterns and not for the other, "early stabilized" patterns. An interesting interpretation is that the properties of the gradually strengthened patterns are all consistent with the Hebbian postulate of "fire together, wire together".
To enable investigation of the relation between interneurons and principal cell assembly patterns from extracellular recordings, as a final contribution this thesis describes a statistical framework for the unsupervised classification of interneurons based on their firing properties alone.
Renewing Athens: the ideology of the past in Roman Greece
Keywords: Philostratus
Pausanias
Roman Greece
2nd Century AD
Panhellenion
benefactor
countryside
euergetism
culture
Greek culture
elite
Ilissos
city
Marathon
renewal
Athens
Hadrianic
Attica
revival
Second Sophistic
urban landscape
estate
Roman Empire
Cephisia
rural landscape
Emperor
villa
gravestone
Milesian
Hadrian
restoration
sacro-idyllic
Antonine
Marcus Aurelius
Herodes Atticus

In this thesis we explore the period of renewal that Athens experienced during the second century AD. This century saw Athens at the peak of her cultural prominence in the Roman Empire: the city was the centre of the League of the Panhellenion and hosted a vibrant sophistic scene that attracted orators from across the Greek world, developments which were ideologically fuelled by contemporary conceptions of Classical Athens. While this Athenian ‘golden age’ is a standard feature of scholarship on Greek culture under Rome, my thesis delves further to explore the renewal of the urban and rural landscapes at this time and the relationship between that process and constructions of Athenian identity.
We approach the renewal of second-century Athens through four lenses: past and present in the Ilissos area; the rhetoric of the Panhellenion; elite conflict and competition; and the character of the Attic countryside. My central conclusions are as follows:
1. The renewal of Athens was effected chiefly by Hadrian and the Athenian elite and was modelled on an ideal Athenian past, strategically manipulated to suit present purpose; the attractions of the fifth-century golden age for this programme of renewal meant that politically contentious history of radical democracy and aggressive imperialism had to be safely rewritten.
2. Athens and Attica retained their uniquely integrated character in the second century. Rural Attica was the subject of a powerful sacro-idyllic ideology and played a vital role in concepts of Athenian identity, while simultaneously serving as a functional landscape of production and inhabitation.
3. The true socio-economic importance of the Attic countryside as a settled and productive landscape should be investigated without unduly privileging the limited evidence from survey, and by combining all available sources, both literary and documentary, with attention to their content, cultural context and ideological relevance.
Brokering anime: how to create a Japanese animation business bridge between Japan and India
Keywords: India
business custom
anime
broker
animation
brokerage
Japan
cross-culturtal management
Asia
entrepreneurship
creative industry

This thesis ethnographically examines the globalising of the Japanese animation (anime) business in the context of the creative industries, of Japan’s politico-economic position in Asia, and of brokerage. Influencing the world’s entertainment, creators, and youth culture, anime is one of the crucial lenses through which one can examine Japan’s presence in the world. Despite the prevalent assumption that anime is globally popular, this thesis highlights the precarious performance of the anime business overseas, and examines it through an entrepreneurial anime business project trying to bridge the Japanese anime business into the Indian market.
The ethnography of the project centres on its founding entrepreneur, focusing on how he tried to ally with insiders in the Japanese anime sector and the Indian market. The thesis’s 12-month fieldwork accompanied his business in Japan (Tokyo) and India (Delhi), revealing a perspective of the entrepreneur as a broker who intermediates between the discrepant positions of his stakeholders to keep his business afloat. It also highlights the two most critical discrepancies: the dichotomies of art versus commerce (one of the central topics in creative industries studies) and the ‘Japanese’ versus ‘Indian’ ways of doing business (one of the prominent topics in Japan’s political economy vis-à-vis the Asian region). The ethnography found the entrepreneur’s liminal dual agency in bridging, blurring and reorienting the dichotomies was a driving force carrying his business forward.
This thesis counterbalances previous anthropological studies on the creative industries (including anime) that tend to advocate the centrality of creators and fans, by focusing on the businessperson in a creative project. It also suggests that the broker is a crucial point of reference when examining how to create workable compromises between art and commerce, and allowing Japanese and Asian businesspeople to get along. The thesis also enhances our understanding of entrepreneurship by revealing most of its function as brokerage.
From actions to agents: value representation in frontal cortex
Keywords: Psychology, cognitive Neuroscience, Decision making, Learning, Reward

In this thesis, I investigated computational and neural mechanisms underlying foraging-related behavior in humans. A consideration of the ecological constraints under which mammalian behavior first evolved guided my investigation of learning and decision-making in frontal cortex. When engaged in foraging, animals have to figure out how profitable their actions are and whether it is better to continue foraging in their current environment or to switch to an alternative. They have to track the reward income of their actions over time and also take into account that the actions of other foraging animals have a direct influence on their reward income (Chapter 1). Based on these observations, I looked at similar types of behavior in humans using computational modeling and functional magnetic resonance imaging. I studied how people evaluate the profitability of their actions over time (Chapter 2). Dorsal anterior cingulate cortex carried a detailed representation of the value of the current foraging action, which was influenced by reward memories with different time constants (Chapter 3). Tracking the reward income of one's actions is not only important in order to learn about the profitability of the environment, it can also inform estimates of one's own and other people's abilities. Ability estimates can be used in a direct way to predict the reward outcome that the actions of one’s own self and others will have. I found that people learn about their own and others' abilities in a rational manner but also that ability estimates of self and other were partly confused with each other, depending on whether subjects cooperated or competed with each other (Chapter 4). The confusion effect is reflected in Brodmann area 9 activity indicating that area 9 integrates self and other related information. Perigenual anterior cingulate tracked the ability estimates for oneself, suggesting that it might compute the success expectation of an action independent of particular features of the environment (Chapter 5). In sum, different subregions of medial frontal cortex carried different types of action-related value representations that can guide decision-making.
Investigation of breathing-disordered sleep quantification using the oxygen saturation signal
Keywords: obstructive sleep apnoea
autoregressive modelling
time and frequency domain analyses

This thesis investigates the feasibility of using the non-invasive biomedical signal of oxygen saturation, or SpO2 , to diagnose a sleep disorder known as Obstructive Sleep Apnoea Hypopnoea Syndrome (OSAHS). Epidemiologically, OSAHS is the most common condition investigated by sleep clinics. In a patient suspected of having the disorder, the upper airway is obstructed during sleep and a cessation in respiration results. An apnoea is defined as a temporary cessation of breathing. Similarly, a hypopnoea is defined as any reduction in breathing (i.e., less severe than an apnoea).
The work has three main objectives; the first being to establish automated evaluation procedures for methods of quantifying apnoeic activity from the SpO2 signal, the second being to accurately identify apnoeic and normal activity on a minute-by-minute basis, the third being to create a Respiratory Disturbance Index (RDI) based on the analysis which is comparable to the gold-standard Apnoea Hypopnoea Index (AHI) derived by experts.
The detection of apnoeic activity is determined using three separate analyses: time domain, frequency domain, and autoregressive modelling with an incorporated amplitude criterion. A training dataset is utilised for algorithm development, and an independent dataset is employed for testing . All three methods result in comparable overall classification accuracies of: 81.2% (time domain), 82.1% (frequency domain), and 80.0% (autoregressive modelling with amplitude). In addition, particular attention is given to the resultant sensitivity, specificity, and accuracy values partitioned according to patient category; i.e., patients with OSAHS may be divided into normal, mild, moderate and severe.
Lastly, a simple RDI is computed based on the automated analyses; i.e., the number of apnoeic segments detected divided by the total number of segments used. A comparison between computed RDI and AHI values for the test database show correlation values above 0.8. In conclusion, this thesis shows that through the automated analysis of the SpO2 signal, OSAHS severity in patients suspected of having the disorder can be quantified. The AR-modelling with an incorporated amplitude criterion, in particular, shows the most promise for further work in this area.
The role of the storyteller in old Norse literature
Keywords: Drama
Medieval
Old Norse
Storytelling
Performance
Middle Ages
Theatre

This thesis examines the figure of the oral storyteller as depicted in various Old Norse literary sources written down during the High Middle Ages, the majority in Iceland, between the mid-twelfth and early fourteenth centuries. It comprises a literary-critical discussion of how storytellers and the art of storytelling are imagined, interpreted and represented within these texts. Where possible, connections are drawn between genres, and across considerable temporal and geographical distances, in order to illustrate the strength and endurance of cultural preoccupations with disguise, narrative structure and the role of intermediaries in different historical and creative contexts.
The central contention is that the eddic poets and saga authors shared a common and profound sensitivity to the metatextual dimension of the storytelling endeavour in which they were engaged, and that this sensitivity manifested itself in strikingly similar ways across the whole period. The thesis is structured thematically, rather than chronologically, in order to foreground enduring cultural trends. The first chapter discusses the metatextual tendencies of the eddic poets, noting their recurring interest in disguise and the assertion (or appropriation) of an identity by characters who feature in their stories. It also includes an analysis of Vǫluspá which suggests that the poem lends itself to recitation by multiple performers. Chapter Two analyses depictions of public storytelling in the sagas and the relationship between writer and oral reciter as presented in the prologues and epilogues composed to ‘frame’ a number of these texts. Chapters Three and Four contain close readings of passages from the Sagas of Icelanders and eddic poetry, which demonstrate how certain characters, often of low social status, temporarily take on the mantle of a storyteller and perform their accounts of events so as to illuminate the texts' broader interest in the mechanics of literary narrative.