Nanoscale Optical and Correlative Microscopies for Quantitative Characterization of DNA Nanostructures

Methods to engineer nanomaterials and devices with uniquely tailored properties are highly sought after in fields such as manufacturing, medicine, energy, and the environment. The macromolecule deoxyribonucleic acid (DNA) enables programmable self-assembly of nanostructures with near arbitrary shape and size and with unprecedented precision and accuracy. Additionally, DNA can be chemically modified to attach molecules and nanoparticles, providing a means to organize active materials into devices with unique or enhanced properties. One particularly powerful form of DNA-based self-assembly, DNA origami, provides robust structures with the potential for nanometer-scale resolution of addressable sites. DNA origami are assembled from one large DNA scaffold strand and many unique, short staple strands; each staple programmatically binds the scaffold at several distant domains, and the coordinated interactions of many staples with the scaffold act to fold the scaffold into a desired shape. The utility of DNA origami has been demonstrated through multiple applications, such as plasmonic and photonic devices, electronic device patterning, information storage, drug delivery, and biosensors. Despite the promise of DNA nanotechnology, few products have successfully translated from the laboratory to industry. Achieving high yield and high-precision synthesis of stable DNA nanostructures is one of the biggest challenges to applications of DNA nanostructures. For adoption in manufacturing, methods to measure and inspect assembled structures (i.e. metrology) are essential. Common high-resolution imaging techniques used to characterize DNA nanostructures, such as atomic force microscopy and transmission electron microscopy, cannot facilitate high-throughput characterization, and few studies have been directed towards the development of improved methods for nanoscale metrology. DNA-PAINT super-resolution microscopy enables high-resolution, multiplexed imaging of reactive sites on DNA nanostructures and offers the potential for inline optical metrology. In this work, nanoscale metrologies utilizing DNA-PAINT were developed for DNA nanostructures and applied to characterize DNA origami arrays and single site defects on DNA origami. For metrology of DNA origami arrays, an embedded, multiplexed optical super-resolution methodology was developed to characterize the periodic structure and defects of two-dimensional arrays. Images revealed the spatial arrangement of structures within the arrays, internal array defects, and grain boundaries between arrays, enabling the reconstruction of arrays from the images. The nature of the imaging technique is also highly compatible with statistical methods, enabling rapid statistical analysis of synthesis conditions. To obtain a greater understanding of DNA origami defects at the scale of individual strands, correlative super-resolution and atomic force microscopies were enabled through the development of a simple and flexible method to bind DNA origami directly to cover glass, simultaneously passivating the surface to single-stranded DNA. High-resolution, correlative microscopy was performed to characterize DNA origami, and spatial correlation in super-resolution optical and topographic images of 5 nm was achieved, validating correlative microscopy for single strand defect metrology. Investigations of single strand defects showed little correlation to structural defects on DNA origami, revealing that most site defects occur on strands that are present in the structure, contrary to prior reports. In addition, the results suggest that the structural stability of DNA origami was decreased by DNA-PAINT imaging. The presented work demonstrated the development and application of advanced characterization techniques for DNA nanostructures, which will accelerate fundamental research and applications of DNA nanotechnology

Operating room first case start times: a metric to assess systems-based practice milestones?

BACKGROUND: Resident competence in peri-operative care is a reflection on education and cost-efficiency. Inspecting pre-existing operating room metrics for performance outliers may be a potential solution for assessing competence. Statistical correlation of problematic benchmarks may reveal future opportunities for educational intervention. METHODS: Case-log database review yielded 3071 surgical cases involving residents over the course of 5 years. Surgery anticipated and actual start times were evaluated for delays and residents were assessed using the days of resident training performed at the time of each corresponding case. Other variables recorded included day of week, attending anesthesiologist name, attending surgeon name, patient age, sex, American Society of Anesthesiologists physical status classification (ASA PS), and in-patient versus day surgery status. Mixed-effect, multi-variable, linear regression determined independent determinants of delay time. RESULTS: The analysis identified day of the week (F = 25.65, P \u3c 0.0001), days of training (F = 8.39, P = 0.0038), attending surgeon (F = 2.67, P \u3c 0.0001), and anesthesiology resident (F = 1.67, P = 0.0012) as independent predictors of delay time for first-start cases, with an overall regression model F = 3.09, r2 = 0.186, and P \u3c 0.0001. CONCLUSIONS: The day of the week and attending surgeon demonstrated significant impact of case delay compared to resident days trained. If a learning curve for first-case start punctuality exists for anesthesiology residents, it is subtle and irrelevant to operating room efficiency. The regression model accounted for only 19% of the variability in the outcome of delay time, indicating a multitude of additional unidentified factors contributing to operating room efficiency

Spatial Database For Intersections

Deciding which intersections in the state of Kentucky warrant safety improvements requires a comprehensive inventory with information on every intersection in the public roadway network. The Kentucky Transportation Cabinet (KYTC) had previously catalogued only those intersections where state-maintained roadways met. However, this inventory did not account for intersections between state- and locally-maintained routes, nor was it designed to accommodate regular updates. As such, the Kentucky Transportation Center (KTC) at the University of Kentucky developed a methodology to create and maintain a full inventory of every intersection in the state. The database contains precise location information as well as several safety and operational attributes for each point of an intersection. By replicating the topology factors used in the Highway Safety Manual (HSM), the research team categorized every intersection type, and developed. Safety Performance Functions (SPF) for each intersection type. The SPFs were used to rank each intersection. It is anticipated that this project’s deliverables will be used to increase KYTC’s ability to effectively allocate funds to maintain and improve intersection safety. Making the database available to expert users will allow continuous improvements. In the future, AADT data and traffic control information could be included

Showcase Panel III: The States and Administrative Law

2018 National Lawyers Convention Transcripts “We live in a system where regulators make the rules, investigate alleged violations of the rules, and then adjudicate those violations before Administrative Law Judges. If the matter ever gets to court, courts generally defer to the agency on questions of law “and fact.” As a result, agencies know that their regulations are unlikely to face challenge and, if they are challenged, will likely be upheld. In this system, critics argue, the predictable result is more and more irrational regulations and enforcement actions. Arizona has first-of-its-kind legislation to “reverse” Chevron and to instruct courts to give no deference to agency decisions on questions of law. On a related note, Arizona also passed the Right to Earn a Living Act, creating a cause of action to challenge occupational licensing decisions under a heightened standard of review. Some contend that the result of this new law has been significant in that regulators are reviewing and improving rules, or repealing them outright, rather than face litigation. Could these measures serve as a model other states and the federal government in reducing the size and scope of, and otherwise improving, the Administrative State?” Speakers:Prof. Nestor Davidson, Albert A. Walsh Chair in Real Estate, Land Use, and Property Law; Faculty Director, Urban Law Center, Fordham University School of Law Prof. Chris Green, Associate Professor of Law and H.L.A. Hart Scholar in Law and Philosophy, University of Mississippi School of Law Prof. Miriam Seifter, Professor of Law, University of Wisconsin Law School Hon. Jeffrey Sutton, United States Court of Appeals, Sixth Circuit Moderator: Hon. Michael Scudder, United States Court of Appeals, Seventh Circuit Credit: The Federalist Society, https://fedsoc.org/conferences/2018-national-lawyers-convention#agenda-item-showcase-panel-iii-the-states-administrative-la

Kentucky Traffic Collision Facts 2020

KENTUCKY’S TRAFFIC COLLISION FACTS report is based on collision reports submitted to the Kentucky State Police Records Branch. As required by Kentucky Revised Statutes 189.635: “Every law enforcement agency whose officers investigate a vehicle accident of which a report must be made...shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau.” The stated purpose of this requirement is to utilize data on traffic collisions for such purposes as will improve the traffic safety program in the Commonwealth

D-brane Wess--Zumino actions, T-duality and the cosmological constant

A geometrical formulation of the T-duality rules for type II superstring Ramond--Ramond fields is presented. This is used to derive the Wess-Zumino terms in superstring D-brane actions, including terms proportional to the mass parameter of the IIA theory, thereby completing partial results in the literature. For non-abelian world-volume gauge groups the massive type IIA D-brane actions contain non-abelian Chern--Simons terms for the Born--Infeld gauge potential, implying a quantization of the IIA cosmological constant.Comment: Version to be published in Physics Letters (minor corrections

Kentucky Traffic Collision Facts 2021 Report

Each year the Kentucky Transportation Center publishes the Traffic Collision Facts report in collaboration with the Commonwealth of Kentucky, Kentucky State Police, and Kentucky Transportation Cabinet. This is the fiscal year 2022 report, which covers collisions reported during calendar year 2021. For the year, 734 fatal crashes, 20,117 nonfatal crashes, and 88,440 property damage only crashes occurred on the state’s roadways. Overall, 109,291 crashes were reported in calendar year 2021, a 8.4 percent increase over calendar year 2020

Climate change, crops and commodity traders : subnational trade analysis highlights differentiated risk exposure

The global food system is increasingly interconnected and under pressure to support growing demand. At the same time, crop production is facing new and uncertain impacts from climate change. To date, understanding how downstream supply chain actors, such as commodity traders, are exposed to climate change risks has been difficult due to a lack of high-resolution climate and trade data. However, the recent availability of supply chain data linking subnational production to downstream actors, and gridded projections of crop yield under climate change, allows us to assess individual commodity trader exposure to long-term climate change risk. We apply such an analysis to soy production in Brazil, the world’s largest soy exporter. Whilst uncertainty across crop models’ yield projections means it remains difficult to accurately predict how production across the region will be affected by climate change, we demonstrate that the risk exposure of trading actors differs substantially due to the heterogeneity in their sourcing. Our study offers a first attempt to analyze subnational climate risk to individual trading actors operating across an entire production landscape, leading to more precise risk exposure analysis. With sufficient subnational data, this method can be applied to any crop and country combination, and in the context of wider food security issues, it will be pertinent to apply these methods across other production systems and downstream actors in the food system. Introductio

Automatic Error Detection in Integrated Circuits Image Segmentation: A Data-driven Approach

Due to the complicated nanoscale structures of current integrated circuits(IC) builds and low error tolerance of IC image segmentation tasks, most existing automated IC image segmentation approaches require human experts for visual inspection to ensure correctness, which is one of the major bottlenecks in large-scale industrial applications. In this paper, we present the first data-driven automatic error detection approach targeting two types of IC segmentation errors: wire errors and via errors. On an IC image dataset collected from real industry, we demonstrate that, by adapting existing CNN-based approaches of image classification and image translation with additional pre-processing and post-processing techniques, we are able to achieve recall/precision of 0.92/0.93 in wire error detection and 0.96/0.90 in via error detection, respectively