Solutions to linear problems in aberrated optical systems

Linear problems are possibly the kindest problems in physics and mathematics. Given sufficient information, the linear equations describing such problems are intrinsically solvable. The solution can be written as a vector having undergone a linear transformation in a vector space; extracting the solution is simply a matter of inverting the transformation. In an ideal optical system, the problem of extracting the object under investigation would be well defined, and the solution trivial to implement. However, real optical systems are all aberrated in some way, and these aberrations obfuscate the information, scrambling it and rendering it inextricable. The process of detangling the object from the aberrated system is no longer a trivial problem or even a uniquely solvable one, and represents one of the great challenges in optics today. This thesis provides a review of the theory behind optical microscopy in the presence of absent information, an architecture for the modern physical and computational methods used to solve the linear inversion problem, and three distinct application spaces of relevance. I hope you find it useful

Complex impedance spectroscopy for monitoring tissue responses to inserted neural implants

A series of animal experiments was conducted to characterize changes in the complex impedance of chronically implanted electrodes in neural tissue. Consistent trends in impedance changes were observed across all animals, characterized as a general increase in the measured impedance magnitude at 1 kHz. Impedance changes reach a peak approximately 7 days post-implant. Reactive responses around individual electrodes were described using immuno- and histo-chemistry and confocal microscopy. These observations were compared to measured impedance changes. Several features of impedance changes were able to differentiate between confined and extensive histological reactions. In general, impedance magnitude at 1 kHz was significantly increased in extensive reactions, starting about 4 days post-implant. Electrodes with extensive reactions also displayed impedance spectra with a characteristic change at high frequencies. This change was manifested in the formation of a semi-circular arc in the Nyquist space, suggestive of increased cellular density in close proximity to the electrode site. These results suggest that changes in impedance spectra are directly influenced by cellular distributions around implanted electrodes over time and that impedance measurements may provide an online assessment of cellular reactions to implanted devices.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58178/2/jne7_4_007.pd

Fabrication and Imaging of Protein Crossover Structures

ABSTRACT Proteins often deform, dehydrate or otherwise denature when adsorbed or patterned directly onto an inorganic substrate, thus losing specificity and biofunctionality. One method used to maintain function is to pattern the protein of interest directly onto another underlying protein or polypeptide that acts as a buffer layer between the substrate and the desired protein. We have used microcontact printing (µcp) to cross-stamp orthogonal linear arrays of two different proteins (e.g., IgG, poly-lysine, protein A) onto glass substrates. This created three separate types of protein-substrate microenvironments, including crossover structures of protein one on protein two. We report preliminary fluorescent microscopy and scanning force microscopy characterization of these structures, including commonly encountered structural defects

Magna Carta, the Rule of Law and the Limits on Government

This paper surveys the legal tradition that links Magna Carta with the modern concepts of the rule of law and the limits on government. It documents that the original understanding of the rule of law included substantive commitments to individual freedom and limited government. Then, it attempts at explaining how and why such commitments were lost to a formalist interpretation of the rule of law from 1848 to 1939. The paper concludes by arguing how a revival of the substantive commitments of the rule of law is central in a project of reshaping modern states

Genome-wide identification and phenotypic characterization of seizure-associated copy number variations in 741,075 individuals

Copy number variants (CNV) are established risk factors for neurodevelopmental disorders with seizures or epilepsy. With the hypothesis that seizure disorders share genetic risk factors, we pooled CNV data from 10,590 individuals with seizure disorders, 16,109 individuals with clinically validated epilepsy, and 492,324 population controls and identified 25 genome-wide significant loci, 22 of which are novel for seizure disorders, such as deletions at 1p36.33, 1q44, 2p21-p16.3, 3q29, 8p23.3-p23.2, 9p24.3, 10q26.3, 15q11.2, 15q12-q13.1, 16p12.2, 17q21.31, duplications at 2q13, 9q34.3, 16p13.3, 17q12, 19p13.3, 20q13.33, and reciprocal CNVs at 16p11.2, and 22q11.21. Using genetic data from additional 248,751 individuals with 23 neuropsychiatric phenotypes, we explored the pleiotropy of these 25 loci. Finally, in a subset of individuals with epilepsy and detailed clinical data available, we performed phenome-wide association analyses between individual CNVs and clinical annotations categorized through the Human Phenotype Ontology (HPO). For six CNVs, we identified 19 significant associations with specific HPO terms and generated, for all CNVs, phenotype signatures across 17 clinical categories relevant for epileptologists. This is the most comprehensive investigation of CNVs in epilepsy and related seizure disorders, with potential implications for clinical practice