VictorJuiz/thesis huggingface dataset:
Martian dust lifting, transport and associated processes
Keywords: Fluid dynamics
Mars
Atmospheric physics

The dust lifting capacity of the UK Mars General Circulation Model has been extended through the development of a new wind stress lifting parameterisation, and the simulation of a finite, variable surface dust layer. This second addition, which was represented by the use of lifting thresholds that were adjusted at each surface gridpoint in response to the removal or deposition of dust, led to enhanced variability in the timing and peak magnitude of major dust storms produced in the model. These dust storms were realistic in many respects, and the observed global dust storm frequency of occurrence of roughly one in every three years was approximately reproduced by the model, but an artificial threshold decrease rate was required to maintain dust lifting on a multiannual timescale - this was believed to be due to inaccuracies in the net cross-equatorial dust flux, which showed a strong bias towards the northern hemisphere. Significant changes were seen in model dust lifting rates when the influence of a heterogeneous surface roughness length was included in the wind stress scheme, and the need for more sophisticated sub-gridscale methods in future dust lifting schemes, to cope with this and other effects, was noted. The inclusion of radiatively active water clouds in model runs also affected dust lifting rates, particularly in the vicinity of the polar caps in autumn, winter and spring. The dynamics behind the formation of small, cap-edge dust storms during these periods were examined in detail, and it was found that a cessation in dust lifting activity that occurs around winter solstice does so due to a combination of the radiative effects of global dust loading and polar hood ice clouds, and zonal variations in midlatitude topography. The direct interaction between dust and ice, in the form of nucleation and scavenging, was investigated. It was found that scavenging by water ice, if it is suitably efficient, could significantly reduce the dust content of the winter polar regions. However, the dust and ice vertical profiles measured in the aphelion cloud belt by Mars Climate Sounder were not reproduced by the model with any of the possible scavenging efficiencies used. It appears that scavenging cannot provide an explanation for the existence of sharply defined, elevated dust layers at low latitudes.
Rethinking money laundering offences: a global comparative analysis
Keywords: money laundering
human rights
financing of terrorism
security
macroeconomics

Since the late 1980s, efforts made by the international community to deal with the complex and global problem of money laundering have stimulated the creation and definition of the so-called 'international crime of money laundering', which is included in various United Nations and Council of Europe international treaties, as well as European Union Directives. The Central purpose of this thesis is to investigate if the main goal of effectiveness in the adaptation of the international crime of money laundering at the domestic level, might undermine other values that international law is seeking to protect, namely the guarantee of due process and the adequate protection of human rights principles. Then, if the adoption of any element of the crime shows to be inconsistent with civil rights and guarantees, to propose how deficiencies could be remedied.
Development and application of an analytical method for radiocarbon dating bones using the amino acid hydroxyproline
Keywords: HPLC
hydroxyproline
archaeological science
anatomically modern humans
radiocarbon dating
accelerator mass spectrometry

Archaeological bones are usually dated by radiocarbon measurement of extracted collagen. However, low collagen content, contamination from the burial environment or museum conservation work have previously lead to inaccurate results, especially for old bones, compromising the ability to reconstruct reliable past chronologies. It is reported, for example, that up to 70% of Palaeolithic radiocarbon dates on bones are likely to be underestimates of the real age, blurring the picture of modern human dispersals and Neanderthal extinction.
In this thesis, a method for isolating and radiocarbon dating the collagen amino acid hydroxyproline is described. Hydroxyproline consists of about 10% of bone collagen but is not found in significant amounts elsewhere in nature. The hydroxyproline dating method uses a mixed-mode (i.e. ion-exchange combined with hydrophobic chemistry), semi preparative HPLC methodology. The amino acids do not require derivatisation, and no organic solvents are used, thereby avoiding addition of carbon. The hypothesis of this thesis is that the hydroxyproline can be used as a bone specific biomarker, improving dating accuracy and making it possible to obtain radiocarbon determinations where previously it has been impossible.
It was calculated that on average 3.3±1.4μg of contaminant carbon are added to each sample in the process of isolating the hydroxyproline, a low level suitable for 14C dating. It was investigated whether a deliberately contaminated bone and 'naturally' contaminated archaeological bones, yielding erroneous dates when dated using the normal pretreatment method, could be dated accurately using this method. In addition, a hydroxyproline date was obtained for a bone with too little surviving collagen to be dateable by the bulk collagen method. Finally, using the hydroxyproline dating method, the earliest direct ages for the presence of anatomically modern humans on the Russian Plain were obtained. The method proved to be a powerful tool that can help resolve longstanding archaeological questions.
Protein complexes in the gas phase: structural insights from ion mobility-mass spectrometry and computational modelling
Keywords: mass spectrometry
ion mobility
protein complexes

Structure determination of macromolecular protein assemblies remains a challenge for well-established experimental methods. In this thesis, an emerging structural technique, ion mobility-mass spectrometry (IM-MS) is explored. An assessment of collision cross section (CCS) measurement accuracy using travelling-wave IM (TWIMS) instrumentation was carried out (Chapter 3). Through the collation of a protein complex CCS database and the development of a calibration framework for TWIMS, significant improvements to CCS measurement accuracy have been achieved. Next, the advantages and limitations of using IM-MS to generate restraints for structure characterisation were explored. Computational tools designed to exploit IM-MS data for structural modelling were developed and tested on a training set of systems (Chapter 4). These include two heteromeric protein complexes, and an oligomeric intermediate involved in beta-2-microglobulin aggregation. Further structural information can be attained by using gas-phase dissociation techniques, such as collision-induced dissociation (CID). The effects of charge state on CCS and the gas-phase dissociation pathway of complexes were investigated (Chapter 5). This highlighted the possibility of using CID in conjunction with supercharging to manipulate dissociation pathways to achieve more useful structural information. Finally, the gas-phase structures of globular and intrinsically disordered protein complexes were probed by IM-MS and molecular dynamics (MD) simulations (Chapter 6). Experimental observations were recapitulated remarkably closely by simulations, including gas-phase structural collapse and the ejection of monomer subunits when the energy of the system was increased sufficiently. Overall, this research has contributed to the IM-MS field by providing the framework for improved CCS measurements of large protein complexes and the use of restraints from IM-MS for structural modelling. Significantly, IM-MS has been used in combination with charge manipulation, CID and MD simulations to reveal further insights into the gas-phase structures, stabilities and dissociation pathways of multimeric protein complexes.
Sparse distance metric learning
Keywords: L1 penalty
sparsity
distance metric learning

A good distance metric can improve the accuracy of a nearest neighbour classifier. Xing et al. (2002) proposed distance metric learning to find a linear transformation of the data so that observations of different classes are better separated. For high-dimensional problems where many un-informative variables are present, it is attractive to select a sparse distance metric, both to increase predictive accuracy but also to aid interpretation of the result. In this thesis, we investigate three different types of sparsity assumption for distance metric learning and show that sparse recovery is possible under each type of sparsity assumption with an appropriate choice of L1-type penalty. We show that a lasso penalty promotes learning a transformation matrix having lots of zero entries, a group lasso penalty recovers a transformation matrix having zero rows/columns and a trace norm penalty allows us to learn a low rank transformation matrix. The regularization allows us to consider a large number of covariates and we apply the technique to an expanded set of basis called rule ensemble to allow for a more flexible fit. Finally, we illustrate an application of the metric learning problem via a document retrieval example and discuss how similarity-based information can be applied to learn a classifier.
Towards a strontium optical lattice clock
Keywords: optical atomic clock
strontium
lattice clock
narrow linewidth laser
quantum frequency metrology

Due to the recent success, in terms of accuracy and precision, of a number of strontium optical lattice optical frequency standards, and the classification of the 5s2 1S0 to 5s5p 3P0 transition in neutral strontium as a secondary definition of the SI unit of the second, many new strontium lattice clocks are under development. The strontium optical lattice clock (Sr OLC) at the National Physical Laboratory (NPL) is one such project. This thesis describes the design and build of the NPL Sr OLC, discussing the considerations behind the design. Details of the first cooling stage are given, which includes the characterisation of a novel permanent-magnet Zeeman slower by measurements of the longitudinal velocity distributions and loading of the MOT at 461 nm. Development of a narrow linewidth laser system at 689 nm is described, which is used for initial spectroscopy of the second-stage cooling transition. In particular, this work describes progress towards two independent ultra-narrow linewidth clock lasers.
The new generation of strontium lattice clock experiments have focused on characterising the systematic frequency shifts and reducing their associated fractional frequency uncertainties, as well as reducing the fractional frequency instability of the measurement. One focus of the Sr OLC at NPL is to help characterise the frequency shift of the clock transition due to black-body radiation (BBR), which is currently the largest contributor to the uncertainty budget of the measured clock frequency. Our approach, discussed here, is to make a direct, differential measurement of the shift with the atoms housed alternately in environments of differing temperatures. Better characterisation and control of the BBR frequency shift of the strontium clock transition is crucial for the future of the Sr OLC as a leading frequency standard.
Finiteness properties of fibre products
Keywords: finiteness properties
homological group theory
geometric group theory
subdirect products

A group Γ is of type Fn for some n ≥ 1 if it has a classifying complex with finite n-skeleton. These properties generalise the classical notions of finite generation and finite presentability.
We investigate the higher finiteness properties for fibre products of groups ... [see pdf file for full abstract].
Searches for CP violation in D+ to K-K+pi+ decays at the LHCb experiment
Keywords: CP violation
flavour physics
charm

This thesis documents searches for direct CP violation in the Cabibbo-suppressed D+ to K-K+pi+ decay at the LHCb experiment. Two complementary analyses are described. Direct CP-violating asymmetries are predicted to exist in singly Cabibbo-suppressed charm decays with magnitudes of up to O(0.001) in the Standard Model, and can be enhanced to the percent level by contributions from new physics. No such asymmetry has yet been observed.
The LHCb detector is a forward spectrometer with a precise vertex detector and powerful particle identification capabilities, designed to collect large, pure samples of charm and B
decays. Data collected at LHCb in 2010 corresponding to an integrated luminosity of 35pb^-1 are used to perform a model-independent search for direct CP violation in the D+ to K-K+pi+ decay. The Dalitz plot is divided into bins and a chi^2 test of the compatibility of the dataset with no CP violation is performed. No evidence of CP violation is found.
A second search for CP violation in the region of the D+ to K-K+pi+ Dalitz plot around the phi resonance is described. The charge asymmetry in this decay is calculated and compared to that in the control channel D+ to Ks(pi+pi-)pi+. The 1.0fb^-1 of data collected at LHCb in 2011 are used. The CP-violating asymmetry is found to be (-0.04+/-0.14+/-0.14)% where the uncertainties are statistical and systematic, respectively. A new observable sensitive to CP violation that varies across the phi resonance is defined and measured, and is consistent with no CP violation at the current level of sensitivity. In addition, the CP-violating asymmetry in the decay Ds+ to Ks pi+ is determined to be (0.61+/-0.83+/-0.14)%. There is no evidence for CP violation in either channel. The prospects for new results using data collected in 2012 are very promising and a significant improvement in our understanding of these decays is anticipated.
Strategies for improving radical cure in P. vivax malaria
Keywords: Plasmodium vivax
radical cure
relapse
Malaria

Plasmodium vivax can no longer be considered a benign cause of malaria with increasing reports of severe vivax malaria emphasising the importance of tackling this neglected parasite globally. Important differences in the lifecycle of P. vivax, in particular, its ability to relapse at varying periods after the primary infection make its control more difficult than P. falciparum. Prevention of relapse is dependent upon effective radical cure of blood and liver stage parasites with primaquine being the only current licensed drug effective against P. vivax hypnozoites.
Despite half a century of its use in malaria treatment, there is still no consensus on how primaquine can be deployed safely and effectively. The aims of this thesis were to review the efficacy of different primaquine regimens in preventing P. vivax relapse, to quantify the risk of recurrence of P. vivax following P. falciparum infection and to determine risk factors for representation with P. vivax. Analyses of primaquine clinical trials conducted till date reveal the inadequacy of data for the recommendation of a uniform high dose regimen across the world. A review of clinical studies using artemether-lumefantrine (AL) for P. falciparum malaria conducted in P. vivax endemic regions demonstrated that P. vivax was paradoxically responsible for the majority of recurrent parasitaemia within 63 days of treatment. AL is highly active against both P. falciparum and P. vivax and hence these recurrences are likely to reflect relapse triggered by activation of dormant liver stages.
To test the hypothesis that febrile illnesses other than malaria may be triggering relapses, risk factors for representation were assessed in Timika, Indonesia, an area endemic to the four main malarial species. The risk of representation with P. vivax was increased in patients initially presenting with non-malarial febrile illnesses (Adjusted Hazards Ratio 1.02-1.14). However, the odds were similar for representation with P. falciparum, suggesting an inherent risk of the patient population to cause representation rather than febrile illnesses. Patients presenting with P. falciparum and severe anaemia were at greatest risk of P. vivax representation. Further clinical studies are needed to ensure more pragmatic treatment regimens and reliable point of care testing for G6PD status to avoid haemolysis due to primaquine. In the interim, the target of primaquine radical cure should be widened to include these high risk groups.
Kelsen and Raz on the continuity of legal systems: applying the accounts in an Australian context
Keywords: Australian Constitutional History
Jurisprudence
Raz
Australian Constitutional Theory
Kelsen
Finnis
Australia
Imperial Law
Legal Systems
Identity
Continuity

This thesis has three objectives. Its primary objective is to examine, and critically evaluate, the theoretical accounts offered by Hans Kelsen and Joseph Raz to explain the temporal continuity and discontinuity of legal systems. In particular, it evaluates the explanatory power of those accounts by combining an abstract analysis of the accounts in principle and an evaluation based on systematically applying them to one concrete, historically circumstanced instance: the legal systems of British derivation in Australia between 1788 and 2001. The thesis thus tests each account’s factual fit: how adequately it corresponds to, accords with, and persuasively makes sense of, the facts – including complex social facts, attitudes and normative standards – for which it purports to offer an account. Second, the thesis aims to demonstrate, more generally, the utility of applying theoretical accounts to a particular historical instance to complement abstract analysis. Third, the thesis aims to advance the understanding of the evolution of Australian legal systems between 1788 and 2001. These three objectives are achieved through the critical exposition and reconstruction of the accounts, their development and enrichment where refinement is appropriate, their application to the specific context of Australia and their evaluation, individually and in comparison.
Improper colourings of graphs
Keywords: telecommunications
random graphs
unit disk graphs
improper colouring
frugal colouring
probabilistic combinatorics
acyclic colouring
graph colouring

We consider a generalisation of proper vertex colouring of graphs, referred to as improper colouring, in which each vertex can only be adjacent to a bounded number t of vertices with the same colour, and we study this type of graph colouring problem in several different settings. The thesis is divided into six chapters. In Chapter 1, we outline previous work in the area of improper colouring. In Chapters 2 and 3, we consider improper colouring of unit disk graphs -- a topic motivated by applications in telecommunications -- and take two approaches, first an algorithmic one and then an average-case analysis. In Chapter 4, we study the asymptotic behaviour of the improper chromatic number for the classical Erdos-Renyi model of random graphs. In Chapter 5, we discuss acyclic improper colourings, a specialisation of improper colouring, for graphs of bounded maximum degree. Finally, in Chapter 6, we consider another type of colouring, frugal colouring, in which no colour appears more than a bounded number of times in any neighbourhood. Throughout the thesis, we will observe a gradient of behaviours: for random unit disk graphs and "large" unit disk graphs, we can greatly reduce the required number of colours relative to proper colouring; in Erdos-Renyi random graphs, we do gain some improvement but only when t is relatively large; for acyclic improper chromatic numbers of bounded degree graphs, we discern an asymptotic difference in only a very narrow range of choices for t.
Amperometric gas sensing
Keywords: gas
ionic liquids
electrochemistry
amperometric sensing
sensors
detection
oxygen

Amperometric gas sensors are widely used for environmental and industrial monitoring. They are sensitive and cheap but suffer from some significant limitations. The aim of the work undertaken in this thesis is the development of ‘intelligent’ gas sensors to overcome some of these limitations. Overall the thesis shows the value of ionic liquids as potential solvents for gas sensors, overcoming issues of solvent volatility and providing a wide potential range for electrochemical measurements. Methods have been developed for sensitive amperometry, the tuning of potentials and especially proof-of-concept (patents Publication numbers: WO2013140140 A3 and WO2014020347 A1) in respect of the intelligent self-monitoring of temperature and humidity by RTIL based sensors. Designs for practical electrodes are also proposed. The specific content is as follows.
Chapter 1 outlines the fundamental principles of electrochemistry which are of importance for the reading of this thesis. Chapter 2 reviews the history and modern amperometric gas sensors. Limitations of present electrochemical approaches are critically established. Micro-electrodes and Room Temperature Ionic Liquids (RTILs) are also introduced in this chapter.
Chapter 4 is focused on the study of analysing chronoamperometry using the Shoup and Szabo equation to simultaneously determine the values of concentration and diffusion coefficient of dissolved analytes in both non-aqueous and RTIL media. A method to optimise the chronoamperometric conditions is demonstrated. This provides an essential experimental basis for IL based gas sensor.
Chapter 5 demonstrates how the oxidation potential of ferrocene can be tuned by changing the anionic component of room temperature ionic liquids. This ability to tune redox potentials has genetic value in gas sensing.
Chapters 6 and 7 describe two novel patented approaches to monitor the local environment for amperometric gas detection. In Chapter 6, an in-situ voltammetric ‘thermometer’ is incorporated into an amperometric oxygen sensing system. The local temperature is measured by the formal potential difference of two redox couples. A simultaneous temperature and humidity sensor is reported in Chapter 7. This sensor shows advantageous features where the temperature sensor is humidity independent and vice versa.
The Shoup and Szabo analysis (Chapter 4) requires ‘simple’ electron transfer and as such the reduction of oxygen in wet RTILs can be complicated by dissolved water.
Chapter 8 proposes a method to stop oxygen reduction at the one electron transfer stage under humid conditions by using phosphonium based RTILs to ‘trap’ the intermediate superoxide ions.
Chapters 9 and 10 report the fabrication of low cost disposable electrodes of various geometries and of different materials. The suitability of these electrode for use as working electrodes for electrochemical experiments in aqueous, non-aqueous and RTIL media is demonstrated. Their capability to be used as working probes for amperometric gas sensing systems is discussed.