Miracle-dz/UniFAR-FTUs huggingface dataset:
The temporoammonic input to the hippocampal CA1 region displays distinctly different synaptic plasticity compared to the Schaffer collateral input in vivo: significance for synaptic information processing

In terms of its sub-regional differentiation, the hippocampal CA1 region receives cortical information directly via the perforant (temporoammonic) path (pp-CA1 synapse) and indirectly via the tri-synaptic pathway where the last relay station is the Schaffer collateral-CA1 synapse (Sc-CA1 synapse). Research to date on pp-CA1 synapses has been conducted predominantly in vitro and never in awake animals, but these studies hint that information processing at this synapse might be distinct to processing at the Sc-CA1 synapse. Here, we characterized synaptic properties and synaptic plasticity at the pp-CA1 synapse of freely behaving adult rats. We observed that field excitatory postsynaptic potentials at the pp-CA1 synapse have longer onset latencies and a shorter time-to-peak compared to the Sc-CA1 synapse. LTP (>24 h) was successfully evoked by tetanic afferent stimulation of pp-CA1 synapses. Low frequency stimulation evoked synaptic depression at Sc-CA1 synapses, but did not elicit LTD at pp-CA1 synapses unless the Schaffer collateral afferents to the CA1 region had been severed. Paired-pulse responses also showed significant differences. Our data suggest that synaptic plasticity at the pp-CA1 synapse is distinct from the Sc-CA1 synapse and that this may reflect its specific role in hippocampal information processing.
High-risk sexual behaviour among HIV–negative MSM in England: behavioural data to inform HIV prevention

This thesis would not have been possible without Fiona Burns and Anthony Nardone, my two main supervisors. They have been there every step of the way, always patient and always ready to read another draft of the thesis chapters. I have learnt so much from them. They have contributed hours of reading and somehow managed to always come back with constructive and supportive feedback. I also cannot thank them enough for their moral support. They have understood the challenges associated with meeting the demands of the PhD and raising a young family and have helped me get through those moments where it all felt too challenging. I would also like to thank Graham Hart and Noel Gill, my other supervisors. They have both been there to ask the right questions including the “so what? ” question, to challenge me and ensure the PhD was on the right track. Their combined guidance and oversight has been invaluable to this thesis. It has been a pleasure to work with them. I would like to thank all of my collaborators and colleagues for their insights and contributions over the years. It has been my privilege to work with all these individuals and teams both within UCL and Public Health England but also those beyond. The HIV team have been patient with my part-time working arrangements while the GUMCAD team have had to endure endless questions about the surveillance system. I also want to thank those who participated in the behavioural study. It was not an easy endeavour but thank you for being enthusiastic and persevering. Special thanks go to Menelaos Pavlou for his support and patience with all my questions about risk predictions models. Thanks also go to Carina and Maryam for the joint efforts in the SANTE project and to Maryam for sharing her knowledge of the viva. It has also been a pleasure to share the PhD journey with Sarah, Ellie, Ibi, Jess, Vicky, Meaghan, Sara, Adamma and David. Your inputs and support have enriched my PhD experience! Thank you. I would like to thank my family and friends who have been brilliant with their encouragements, and sometimes much required pep talks. I especially want to thank my family for being there and ungrudgingly providing child care when the PhD took over my life. And finally, to Anil: you have been unwavering, patient and supportive beyond what words can describe. Thank you for taking charge at bath- and bedtimes and keeping me supplied with food and drink. I am grateful (and probably quite a lucky girl! ) that you have been by my side through this journey.
The role of social factors in bilingual speech processing : the case of Galician 'new speakers'

It has long been debated whether speech processing remains flexible in adulthood. This thesis contributes to our understanding of this question by investigating bilingual speech development in a naturalistic setting. Galician ‘new speakers’ (neofalantes) are unbalanced bilinguals raised with Spanish as a primary language, who learn Galician at an early age in a bilingual environment, but in adolescence, decide to switch to using Galician almost exclusively, for ideological reasons. Study 1 examined whether neofalantes changed aspects of their production and perception of Galician post-switch. Change was inferred by comparing this group to two control groups, Galician-dominant and Spanishdominant bilinguals. Results showed that neofalantes pattern with Spanishdominants in their perception and production of mid-vowel and fricative contrasts, but with Galician-dominants in their realisation of unstressed word-final vowels, a highly salient feature of Galician. However, Study 2 demonstrated that these shifts in production were not sufficient to enable Galician listeners to identify the neofalantes’ accent as a distinctive variety. Instead, neofalantes were categorised as both Galicianand Spanish-dominant speakers. Study 3 used eye-tracking to investigate the effects of language dominance and long-term language switch on spoken word recognition. Results showed that recognition was slower for Spanish-dominants, however, the level of lexical activation of the confusable competitors was similar for Galicianand Spanishdominant groups. Like in perception tasks, neofalantes behaved more simi-
Place and Placing Locations: A Cognitive Perspective

Understanding and modelling places is an interdisciplinary problem, and one relevant but easily overlooked discipline is cognitive science. Many of the findings and intuitions that geographers and geographic information scientists have developed imply that places (at least, those that subtend a geographic area and do not have sharply defined boundaries) have a specific role and structure in human cognition: one of categorizing contiguous and semantically related locations, to optimize cognitive economy and efficiency. Thus “place”, in this sense, is a classification heuristic. This short paper will outline some of the new research questions that arise if we take this perspective on places, and suggest that computational and/or statistical models will need to be supplemented and “ground truthed” by human-participants work for useful progress to be made.
Quadratic Forms and Space-Time Block Codes From Generalized Quaternion and Biquaternion Algebras

In the context of space-time block codes (STBCs), the theory of generalized quaternion and biquaternion algebras (i.e., tensor products of two quaternion algebras) over arbitrary base fields is presented, as well as quadratic form theoretic criteria to check if such algebras are division algebras. For base fields relevant to STBCs, these criteria are exploited, via Springer's theorem, to construct several explicit infinite families of (bi-)quaternion division algebras. These are used to obtain new 2 × 2 and 4 × 4 STBCs.
A declarative debugger for Haskell

This thesis is about the design and implementation of a debugging tool which helps Haskell programmers understand why their programs do not work as intended. The traditional debugging technique of examining the program execution step-by-step, popular with imperative languages, is less suitable for Haskell because its unorthodox evaluation strategy is difficult to relate to the structure of the original program source code. We build a debugger which focuses on the high-level logical meaning of a program rather than its evaluation order. This style of debugging is called declarative debugging, and it originated in logic programming languages. At the heart of the debugger is a tree which records information about the evaluation of the program in a manner which is easy to relate to the structure of the program. Links between nodes in the tree reflect logical relationships between entities in the source code. An error diagnosis algorithm is applied to the tree in a top-down fashion, searching for causes of bugs. The search is guided by an oracle, who knows how each part of the program should behave. The oracle is normally a human — typically the person who wrote the program — however, much of its behaviour can be encoded in software. An interesting aspect of this work is that the debugger is implemented by means of a program transformation. That is, the program which is to be debugged is transformed into a new one, which when evaluated, behaves like the original program but also produces the evaluation tree as a side-effect. The transformed program is augmented with code to perform the error diagnosis on the tree. Running the transformed program constitutes the evaluation of the original program plus a debugging
Length-limited variable-to-variable length codes for high-performance entropy coding

Arithmetic coding achieves a superior coding rate when encoding a binary source, but its lack of speed makes it an inferior choice when true high-performance encoding is needed. This paper presents the practical implementation of fast entropy coders for binary messages utilizing only bit shifts and table lookups. To limit code table size the proposed code lengths is limited with a type of variable-to-variable (VV) length code created from source string merging. This is referred to as "merged codes". With merged codes it is possible to achieve a desired level of speed by adjusting the number of bits read from the source at each step. The most efficient merged codes yield a coder with a worst-case inefficiency of 0.4%, relative to the Shannon entropy. Using a hybrid Golomb-VV bin coder the compression ratio that is competitive with other state-of-the-art coders, at a superior throughput is achieved.
PeriScope: An active measurement API

|Growing interest in inference and prediction of network characteristics is justi ed by its importance for a variety of network-aware applications. One widely adopted strategy to characterize network conditions relies on active, end-to-end probing of the network. Active end-to-end probing techniques di er in (1) the structural composition of the probes they use (e.g., number and size of packets, the destination of various packets, the protocols used, etc.), (2) the entity making the measurements (e.g. sender vs. receiver), and (3) the techniques used to combine measurements in order to infer speci c metrics of interest. In this paper, we present Periscope: a Linux API that enables the de nition of new probing structures and inference techniques from user space through a exible interface. PeriScope requires no support from clients beyond the ability to respond to ICMP ECHO REQUESTs and is designed to minimize user/kernel crossings and to ensure various constraints (e.g., back-to-back packet transmissions, ne-grained timing measurements) We show how to use Periscope for two di erent probing purposes, namely the measurement of shared packet losses between pairs of endpoints and for the measurement of subpath bandwidth. Results from Internet experiments for both of these goals are also presented. Keywords| End-to-end measurement; loss rate; bottleneck bandwidth; Bayesian probing; Cartouche probing; network-aware applications.
Limb blood flow and vascular conductance are reduced with age in healthy humans: relation to elevations in sympathetic nerve activity and declines in oxygen demand.

BACKGROUND We tested the hypothesis that basal (resting) limb blood flow and vascular conductance are reduced with age in adult humans and that these changes are related to elevations in sympathetic vasoconstrictor nerve activity and reductions in limb oxygen demand. METHODS AND RESULTS Sixteen young (28+/-1 years; mean+/-SEM) and 15 older (63+/-1 years) healthy normotensive adult men were studied. Diastolic blood pressure and body fat were higher (P<0.005) in the older men, but there were no other age-related differences in subject characteristics. Femoral artery blood flow (Doppler ultrasound) was 26% lower in the older men (P<0.005), despite similar levels of cardiac output (systemic arterial blood flow) in the 2 groups. Femoral artery vascular conductance was 32% lower and femoral vascular resistance was 45% higher in the older men (P<0. 005). Muscle sympathetic nerve activity (peroneal microneurography) was 74% higher in the older men (P<0.001) and correlated with femoral artery blood flow (r=-0.55, P<0.005), vascular conductance (r=-0.65, P<0.001), and vascular resistance (r=0.61, P<0.001). The age-related differences in femoral hemodynamics were no longer significant after correction for the influence of muscle sympathetic nerve activity. There were no significant age-group differences in leg tissue mass (by dual-energy x-ray absorptiometry), but estimated leg oxygen consumption was 15% lower in the older men (P<0.001). Femoral artery blood flow was directly related to estimated leg oxygen consumption (r=0.78, P<0.001). The age-group differences in femoral artery blood flow were no longer significant after correction for estimated leg oxygen consumption by ANCOVA. CONCLUSIONS (1) Basal whole-leg arterial blood flow and vascular conductance are reduced with age in healthy adult men; (2) these changes are associated with elevations in sympathetic vasoconstrictor nerve activity; and (3) the lower whole-limb blood flow is related to a lower oxygen demand that is independent of tissue mass.
Dietary Fat Intake Determines the Effect of a Common Polymorphism in the Hepatic Lipase Gene Promoter on High-Density Lipoprotein Metabolism: Evidence of a Strong Dose Effect in This Gene-Nutrient Interaction in the Framingham Study

Background—Gene-nutrient interactions affecting high-density lipoprotein cholesterol (HDL-C) concentrations may contribute to the interindividual variability of the cardiovascular disease risk associated with dietary fat intake. Hepatic lipase (HL) is a key determinant of HDL metabolism. Four polymorphisms in linkage disequilibrium have been identified in the HL gene (LIPC), defining what is known as the −514T allele. This allele has been associated with decreased HL activity and increased HDL-C concentrations. However, the effect is variable among populations. Methods and Results—We have examined interaction effects between the −514(C/T) LIPC polymorphism, dietary fat, and HDL-related measures in 1020 men and 1110 women participating in the Framingham Study. We found a consistent and highly significant gene-nutrient interaction showing a strong dose-response effect. Thus, the T allele was associated with significantly greater HDL-C concentrations only in subjects consuming <30% of energy from fat (P <0.001). When total fat intake was ≥30% of energy, mean HDL-C concentrations were lowest among those with the TT genotype, and no differences were observed between CC and CT individuals. We found similar gene-nutrient interactions when the outcome variables were HDL2-C (P <0.001), large HDL subfraction (P <0.001), or HDL size (P =0.001). These interactions were seen for saturated and monounsaturated fat intakes (highly correlated with animal fat in this population), but not for polyunsaturated fat. Conclusions—Dietary fat intake modifies the effect of the −514(C/T) polymorphism on HDL-C concentrations and subclasses. Specifically, in the Framingham Study, TT subjects may have an impaired adaptation to higher animal fat diets that could result in higher cardiovascular risk.
A UML-based Approach to Design Parallel and Distributed Applications

Parallel and distributed application design is a major area of interest in the domain of high performance scientific and industrial computing. Over the years, various approaches have been proposed to aid parallel program developers to modeling their applications. In this paper it will be used some concepts from agile development methodologies and Unified Modeling Language (UML) to modeling parallel and distributed applications. The UML-based approach of this paper describes through different artifacts and graphs the main flows of events in the development of parallel and high performance applications. Here, we presented three work flows to describe and to model our parallel program, Domain Model, Design and Modeling and Test. All these phases of the development software allow to programmers convert the requirements of the problem in a good and efficient solution.
Decomposition and Distribution of Humorous Effect in Interactive Systems

We aim to identify and control unintentional humor occurring in human-computer interaction, and recreate it intentionally. In this research we focus on text prediction systems, a type of interactive programs employed in mobile phones, search engines, and word processors. More specifically, we identified two design principles, inspired by humor and emotion theories, and implemented them in a proof-of-concept tool simulating a specific type of text prediction.
Influence of differentiation and cell kinetics on the susceptibility of the rat mammary gland to carcinogenesis.

The susceptibility of the rat mammary gland to carcinogenesis decreases with aging and is nullified by pregnancy and lactation. This work was carried out to determine whether these differences in susceptibility to carcinogenesis are the result of variations in cell kinetics induced by both aging and parity. Cell cycle (Tc) and growth fraction (GF) were studied in the mammary gland epithelium of young virgin, old virgin, and parous Sprague-Dawley rats. For the study of Tc, five young virgin, five old virgin, and five parous rats received while in estrus an i.p. injection of 1.7 muCi [3H] thymidine per g body weight. Mammary gland biopsies were taken at 2-hr intervals for the first 24 hr and every 4 hr thereafter up to 72 hr. GF was determined in two young virgin, two old virgin, and two parous rats in which an osmotic minipump releasing 1 microCi [3H]thymidine per hr was implanted i.p. After 5 days, the animals were killed, and the mammary glands were removed. Mammary gland biopsies and whole glands were fixed in Bouin's fluid and embedded in paraffin. Deparaffinized sections were processed for autoradiography. The labeled mitosis wave, labeling index, and GF were determined. The results indicated that, in young virgin rats, mammary gland Tc was 9.9 hr in the most undifferentiated structures (terminal end buds), lengthening to 17.3 hr in terminal ducts (TD) and to 28.2 hr in alveolar buds (AB). In the mammary gland of old virgin rats, Tc was 18.75 hr in terminal ducts in regression, 20.57 hr in TD, and 30.75 hr in AB. In parous rats, mammary gland Tc was 23.9 hr in TD and 49.63 hr in AB. Lengthening of Tc in all of these structures was due to a lengthening of G1, while the duration of the other phases of the cell cycle remained unchanged. GF was 0.55 in terminal end buds of young virgin rats, decreasing to 0.39 and 0.13 in TD and AB, respectively. In terminal ducts in regression of old virgin rats, GF was 0.19, decreasing to 0.054 and 0.030 in TD and AB, respectively. In TD and AB of parous rat, mammary gland GF was 0.009 and 0.004, respectively. These results suggest that the high susceptibility to carcinogenesis that has been demonstrated in young virgin rats is due to the presence of a large proliferative compartment, mainly in terminal end buds and TD, while the low susceptibility of parous animals is due to the formation of a large compartment of nonproliferating cells, and that those cells still proliferating have a longer G1 than do those of young and old virgin rats.
A new pruning algorithm for Feedforward Neural Networks

The number of neurons in hidden layers of Feedforward Neural Networks is very relative to their learning ability and generalization ability. The Iterative Pruning(IP) algorithm spends much time computing adjusting factors of the remaining weights. So the Improved Iterative Pruning(IIP) algorithm is put forward, which adopts dividing blocks strategy and uses the Generalized Inverse Matrix(GIM) algorithm to replace the Conjugate Gradient Precondition Normal Equation(CGPCNE) algorithm for updating the remaining weights. The IIP algorithm is applied in the hidden layers of Feedforward Neural Networks to simplify their structures in a great extent and preserve a good level of accuracy and generalization ability without retraining after pruning. The simulation results demonstrate the effectiveness and the feasibility of the algorithm.
Fixed-Rate Raptor Code Performance Over Correlated Rayleigh Fading Channels

This work considers fixed-rate Raptor coded transmission over fading channels with memory following the Jakes' model. The effect of the normalized fade rate on the performance of low-to-moderate rate Raptor codes, when decoded with an improved soft-decision decoding algorithm, is investigated. Results show that, over slow fading channels, the performance of Raptor codes degrades from that of memoryless (fast) fading by 1.5-4.3 dB. Despite this degradation, Raptor codes are shown to provide substantial performance gains of 3-4 dB over serial and parallel concatenated turbo codes, demonstrating their effectiveness as high-performance codes over correlated fading channels.
Repensando las prácticas académicas: el diseño colaborativo de un proyecto de investigación a partir de la metodología IAP

ParticiPat es un proyecto de investigación del Plan Nacional que tiene como objetivo analizar la participación y sus instrumentalizaciones en nueve estudios de caso sobre procesos de patrimonialización. A la hora de abordar el proyecto, quisimos cuestionar las jerarquías y lógicas raramente colaborativas que rodean la producción de conocimiento en la antropología. Para ello decidimos seguir los principios de la investigación acción participativa (IAP) para elaborar conjuntamente una guía de campo de mínimos que facilitara la comparabilidad de los casos de estudio. A través de la descripción de este proceso participativo reflexionamos sobre la estructuración de los proyectos de investigación, entendiendo que su arquitectura inicial condiciona la reproducción de lógicas de poder y autoridad entre las personas investigadoras. Asumimos así el reto de investigar sobre participación desde un meta diseño de investigación participativo que nos permite visibilizar algunos presupuestos ideológicos dentro de la práctica académica.
Semantic Layers for Illustrative Volume Rendering

Direct volume rendering techniques map volumetric attributes (e.g., density, gradient magnitude, etc.) to visual styles. Commonly this mapping is specified by a transfer function. The specification of transfer functions is a complex task and requires expert knowledge about the underlying rendering technique. In the case of multiple volumetric attributes and multiple visual styles the specification of the multi-dimensional transfer function becomes more challenging and non-intuitive. We present a novel methodology for the specification of a mapping from several volumetric attributes to multiple illustrative visual styles. We introduce semantic layers that allow a domain expert to specify the mapping in the natural language of the domain. A semantic layer defines the mapping of volumetric attributes to one visual style. Volumetric attributes and visual styles are represented as fuzzy sets. The mapping is specified by rules that are evaluated with fuzzy logic arithmetics. The user specifies the fuzzy sets and the rules without special knowledge about the underlying rendering technique. Semantic layers allow for a linguistic specification of the mapping from attributes to visual styles replacing the traditional transfer function specification.