Intelligent decision support systems for optimised diabetes

Computers now pervade the field of medicine extensively; one recent innovation is the development of intelligent decision support systems for inexperienced or non-specialist pbysicians, or in some cases for use by patients. In this thesis a critical review of computer systems in medicine, with special reference to decision support systems, is followed by a detailed description of the development and evaluation of two new, interacting, intelligent decision support systems in the domain of diabetes. Since the discovery of insulin in 1922, insulin replacement therapy for the treatment of diabetes mellitus bas evolved into a complex process; there are many different formulations of insulin and much more information about the factors which affect patient management (e.g. diet, exercise and progression of complications) are recognised. Physicians have to decide on the most appropriate anti-diabetic therapy to prescribe to their patients. Insulin-treated patients also have to monitor their blood glucose and decide how much insulin to inject and when to inject it. In order to help patients determine the most appropriate dose of insulin to take, a simple-to-use, hand-held decision support system has been developed. Algorithms for insulin adjustment have been elicited and combined with general rules of therapy to offer advice for every dose. The utility of the system has been evaluated by clinical trials and simulation studies. In order to aid physician management, a clinic-based decision support system has also been developed. The system provides wide-ranging advice on all aspects of diabetes care and advises an appropriate therapy regimen according to individual patient circumstances. Decisions advised by the pbysician-related system have been evaluated by a panel of expert physicians and the system has undergone informal primary evaluation within the clinic setting. An interesting aspect of both systems is their ability to provide advice even in cases where information is lacking or uncertain

Probing open- and closed-channel p-wave resonances

We study the near-threshold molecular and collisional physics of a strong $^{40}$K p-wave Feshbach resonance through a combination of measurements, numerical calculations, and modeling. Dimer spectroscopy employs both radio-frequency spin-flip association in the MHz band and resonant association in the kHz band. Systematic uncertainty in the measured binding energy is reduced by a model that includes both the Franck-Condon overlap amplitude and inhomogeneous broadening. Coupled-channels calculations based on mass-scaled $^{39}$K potentials compare well to the observed binding energies and also reveal a low-energy p-wave shape resonance in the open channel. Contrary to conventional expectation, we observe a nonlinear variation of the binding energy with magnetic field, and explain how this arises from the interplay of the closed-channel ramping state with the near-threshold shape resonance in the open channel. We develop an analytic two-channel model that includes both resonances as well as the dipole-dipole interactions which, we show, become important at low energy. Using this parameterization of the energy dependence of the scattering phase, we can classify the studied $^{40}$K resonance as broad. Throughout the paper, we compare to the well understood s-wave case, and discuss the significant role played by van der Waals physics. The resulting understanding of the dimer physics of p-wave resonances provides a solid foundation for future exploration of few- and many-body orbital physics.Comment: v4: new appendi

Post-critical set and non existence of preserved meromorphic two-forms

We present a family of birational transformations in $CP_2$ depending on two, or three, parameters which does not, generically, preserve meromorphic two-forms. With the introduction of the orbit of the critical set (vanishing condition of the Jacobian), also called ``post-critical set'', we get some new structures, some "non-analytic" two-form which reduce to meromorphic two-forms for particular subvarieties in the parameter space. On these subvarieties, the iterates of the critical set have a polynomial growth in the \emph{degrees of the parameters}, while one has an exponential growth out of these subspaces. The analysis of our birational transformation in $CP_2$ is first carried out using Diller-Favre criterion in order to find the complexity reduction of the mapping. The integrable cases are found. The identification between the complexity growth and the topological entropy is, one more time, verified. We perform plots of the post-critical set, as well as calculations of Lyapunov exponents for many orbits, confirming that generically no meromorphic two-form can be preserved for this mapping. These birational transformations in $CP_2$, which, generically, do not preserve any meromorphic two-form, are extremely similar to other birational transformations we previously studied, which do preserve meromorphic two-forms. We note that these two sets of birational transformations exhibit totally similar results as far as topological complexity is concerned, but drastically different results as far as a more ``probabilistic'' approach of dynamical systems is concerned (Lyapunov exponents). With these examples we see that the existence of a preserved meromorphic two-form explains most of the (numerical) discrepancy between the topological and probabilistic approach of dynamical systems.Comment: 34 pages, 7 figure

Global Diversity of Ascidiacea

The class Ascidiacea presents fundamental opportunities for research in the fields of development, evolution, ecology, natural products and more. This review provides a comprehensive overview of the current knowledge regarding the global biodiversity of the class Ascidiacea, focusing in their taxonomy, main regions of biodiversity, and distribution patterns. Based on analysis of the literature and the species registered in the online World Register of Marine Species, we assembled a list of 2815 described species. The highest number of species and families is found in the order Aplousobranchia. Didemnidae and Styelidae families have the highest number of species with more than 500 within each group. Sixty percent of described species are colonial. Species richness is highest in tropical regions, where colonial species predominate. In higher latitudes solitary species gradually contribute more to the total species richness. We emphasize the strong association between species richness and sampling efforts, and discuss the risks of invasive species. Our inventory is certainly incomplete as the ascidian fauna in many areas around the world is relatively poorly known, and many new species continue to be discovered and described each year

Causal effect of plasminogen activator inhibitor type 1 on coronary heart disease

Background--Plasminogen activator inhibitor type 1 (PAI-1) plays an essential role in the fibrinolysis system and thrombosis. Population studies have reported that blood PAI-1 levels are associated with increased risk of coronary heart disease (CHD). However, it is unclear whether the association reflects a causal influence of PAI-1 on CHD risk. Methods and Results--To evaluate the association between PAI-1 and CHD, we applied a 3-step strategy. First, we investigated the observational association between PAI-1 and CHD incidence using a systematic review based on a literature search for PAI-1 and CHD studies. Second, we explored the causal association between PAI-1 and CHD using a Mendelian randomization approach using summary statistics from large genome-wide association studies. Finally, we explored the causal effect of PAI-1 on cardiovascular risk factors including metabolic and subclinical atherosclerosis measures. In the systematic meta-analysis, the highest quantile of blood PAI-1 level was associated with higher CHD risk comparing with the lowest quantile (odds ratio=2.17; 95% CI: 1.53, 3.07) in an age- and sex-adjusted model. The effect size was reduced in studies using a multivariable-adjusted model (odds ratio=1.46; 95% CI: 1.13, 1.88). The Mendelian randomization analyses suggested a causal effect of increased PAI-1 level on CHD risk (odds ratio=1.22 per unit increase of log-transformed PAI-1; 95% CI: 1.01, 1.47). In addition, we also detected a causal effect of PAI-1 on elevating blood glucose and high-density lipoprotein cholesterol. Conclusions--Our study indicates a causal effect of elevated PAI-1 level on CHD risk, which may be mediated by glucose dysfunction

Spatial variability in the structure of fish assemblages associated with Laminaria hyperborea forests in the NE Atlantic

Understanding fish-habitat associations is critical for ecosystem-based approaches to management and conservation. Kelp species, which are estimated to inhabit around 25% of the world's coastline and underpin highly productive and biodiverse ecosystems, are widely recognised as important nursery and foraging habitats for coastal fish species. However, quantitative assessments of fish assemblages within kelp forests are lacking for many regions. Here, we used Baited Remote Underwater Video (BRUV) and Underwater Visual Census (UVC) to quantify fish assemblages in Laminaria hyperborea forests at eight shallow subtidal rocky reefs that spanned 9° of latitude in the United Kingdom (UK). Fish assemblages were a ubiquitous and conspicuous component of kelp forest communities at all sites. BRUV surveys recorded marked regional-scale variability, with latitudinal shifts in assemblage structure and particularly distinct assemblages recorded in southwest England. These patterns were largely due to greater abundances of Pollachius spp. (i.e. saithe and pollock) in northern regions and higher numbers of Gobiusculus flavescens (two-spotted goby) and labrid species (i.e. rock cook, goldsinny and ballan wrasses) in southern regions. Unlike BRUVs, UVC surveys did not detect significant regional-scale variation in assemblage structure but did detect significant site-level differences, highlighting differences between the two techniques. BRUV surveys also recorded clear latitudinal trends in richness, with more taxa recorded at lower latitudes. Fish assemblages in the NE Atlantic have been, and will continue to be, impacted by ocean warming and fishing activities. Greater spatiotemporal coverage of kelp forest surveys and ongoing robust monitoring is needed to better understand and manage future ecological changes

Climate‐driven substitution of foundation species causes breakdown of a facilitation cascade with potential implications for higher trophic levels

1. Climate change can alter ecological communities both directly, by driving shifts in species distributions and abundances, and indirectly by influencing the strength and direction of species interactions. Within benthic marine ecosystems, foundation species such as canopy -forming macro-algae often underpin important cascades of facilitative interactions. 2. We examined the wider impacts of climate-driven shifts in the relative abundances of foundation species within a temperate reef system, with particular focus on a habitat cascade whereby kelp facilitate epiphytic algae that in turn facilitate mobile invertebrates. Specifically we tested whether the warm water kelp Laminaria ochroleuca, which has proliferated in response to recent warming trends, facilitated a secondary habitat-former (epiphytic algae on stipes) and associated mobile invertebrates, to the same degree as the cold water kelp Laminaria hyperborea. 3. The facilitative interaction between kelp and stipe-associated epiphytic algae was dramatically weaker for the warm water foundation species, leading to breakdown of a habitat cascade and impoverished associated faunal assemblages. On average, the warm water kelp supported >250 times less epiphytic algae (by biomass) and >50 times fewer mobile invertebrates (by abundance) than the cold water kelp. Moreover, by comparing regions of pre and post range expansion by L. ochroleuca, we found that warming-impacted kelp forests supported around half the biomass of epiphytic algae and one-fifth of the abundance of mobile invertebrates, per unit area, compared with unimpacted forests. We suggest that disruption to this facilitation cascade has the potential to impact upon higher trophic levels, specifically kelp forest fishes, through lower prey availability. 5. Synthesis. Climate-driven shifts in species’ distributions and the relative abundances of foundation organisms will restructure communities and alter ecological interactions, with consequences for ecosystem functioning. We show that climate-driven substitutions of seemingly similar foundation species can alter local biodiversity and trophic processes in temperate marine ecosystems

P-wave interactions in a spin-polarized Fermi gas with and without confinement

Spin-polarized Fermi gases can only interact with exchange anti-symmetric pair wave functions. The resulting p-wave interactions are less well studied than the s-wave case. We improve our understanding and measure Feshbach resonance-enhanced p-wave interactions in fermionic Potassium (40K) with and without low-dimensional confinement. We first parameterize the three-dimensional (3D) resonance through a combination of coupled-channels calculations, a two-channel model, and dimer binding energies measured through resonant and spin-flip association. This benchmarks 3D interactions, which underlie lower-dimensional scattering. We attain confinement by loading atoms into two orthogonal standing waves to produce an ensemble of quasi-one-dimensional (q1D) tubes. We measure correlation strength through a connection between the power-law tail of radio-frequency transfer spectra and the 1D p-wave contact. Tuning of the magnetic field from the 3D resonance shows not only a confinement-induced resonance shift, but also additional features in a broader regime that arise due to collisions in transverse excited bands. Our studies build a foundation for further exploration of few- and many- body states in spin-polarized Fermi gases. AFOSR FA9550-19-1-0365, NSERC