Towards an Information Theoretic Framework for Evolutionary Learning

The vital essence of evolutionary learning consists of information flows between the environment and the entities differentially surviving and reproducing therein. Gain or loss of information in individuals and populations due to evolutionary steps should be considered in evolutionary algorithm theory and practice. Information theory has rarely been applied to evolutionary computation - a lacuna that this dissertation addresses, with an emphasis on objectively and explicitly evaluating the ensemble models implicit in evolutionary learning. Information theoretic functionals can provide objective, justifiable, general, computable, commensurate measures of fitness and diversity. We identify information transmission channels implicit in evolutionary learning. We define information distance metrics and indices for ensembles. We extend Price\u27s Theorem to non-random mating, give it an effective fitness interpretation and decompose it to show the key factors influencing heritability and evolvability. We argue that heritability and evolvability of our information theoretic indicators are high. We illustrate use of our indices for reproductive and survival selection. We develop algorithms to estimate information theoretic quantities on mixed continuous and discrete data via the empirical copula and information dimension. We extend statistical resampling. We present experimental and real world application results: chaotic time series prediction; parity; complex continuous functions; industrial process control; and small sample social science data. We formalize conjectures regarding evolutionary learning and information geometry

Towards laser driven table-top coherent diffractive X-ray microscopy of cultured hippocampal neurons

Neurodegenerative diseases such as Alzheimer’s disease have a huge impact on the world population; over 44 million people worldwide and 850,000 in the UK were recorded as living with dementia in 2013. There are numerous theories attempting to explain the cause of Alzheimer’s disease. Histology from the brains of people who had Alzheimer’s disease shows neurofibilliary tangles and amyloid plaques. Their role in the mechanism of disease is not yet completely understood but we envisage that novel imaging techniques may aid understanding. We present initial data collected using confocal fluorescence microscopy and hard X-ray scanning diffractive microscopy (ptychography) on cultured neuron samples plus high resolution large field of view imaging of test samples from a soft X-ray lab based high harmonic generation (HHG) source

Ptychographic coherent diffractive imaging with orthogonal probe relaxation

Ptychography is a scanning coherent diffractive imaging (CDI) technique that relies upon a high level of stability of the illumination during the course of an experiment. This is particularly an issue for coherent short wavelength sources, where the beam intensity is usually tightly focused on the sample in order to maximize the photon flux density on the illuminated region of the sample and thus a small change in the beam position results in a significant change in illumination of the sample. We present an improved ptychographic method that allows for limited stability of the illumination wavefront and thus significantly improve the reconstruction quality without additional prior knowledge. We have tested our reconstruction method in a proof of concept experiment, where the beam instability of a visible light source was emulated using a piezo driven mirror, and also in a short wavelength microscopy CDI setup using a high harmonic generation source in the extreme ultraviolet range. Our work shows a natural extension of the ptychography method that paves the way to use ptychographic imaging with any limited pointing stability coherent source such as free electron or soft X-ray lasers and improve reconstruction quality of long duration synchrotron experiments

High resolution, wide field of view, ptychographic imaging of a biological sample using a high harmonic generation source

We present coherent diffractive imaging with broadband radiation generated from a high harmonic source around 29nm wavelength to image neuron tissue from the mouse hypothalamus to 80nm resolution over a 40nm field of view

An Effective Diabetic Ketoacidosis Prevention Intervention in Children With Type 1 Diabetes

The objective of this study was to evaluate the effectiveness of a brief, office-based educational intervention to increase parent or patient recognition of the early warning signs and symptoms of diabetic ketoacidosis (DKA). Forty-two patients aged > 13 years and 34 parents of children aged ≤ 13 years were given a pretest questionnaire about their knowledge of signs and symptoms of DKA and sick day management practices. They received a brief refresher course on sick day management specific to their treatment modality (pump vs. injection) and were given a take-home flow sheet of guidelines for diabetes sick day management. Subjects were retested with the same knowledge questionnaire after 6 to 12 months. Patients or parents scored higher on the posttest than the pretest and called the emergency line for assistance more frequently ( p  = .032) following the intervention. Emergency department visits were significantly reduced in adolescents ( p  = .024). A short educational intervention and printed management tool is effective in improving sick day and DKA knowledge and appears to be effective in reducing emergency department visits by increasing utilization of a diabetes emergency line for early outpatient intervention