A geometric and structural approach to the analysis and design of biological circuit dynamics: a theory tailored for synthetic biology

Much of the progress in developing our ability to successfully design genetic circuits with predictable dynamics has followed the strategy of molding biological systems to fit into conceptual frameworks used in other disciplines, most notably the engineering sciences. Because biological systems have fundamental differences from systems in these other disciplines, this approach is challenging and the insights obtained from such analyses are often not framed in a biologically-intuitive way. Here, we present a new theoretical framework for analyzing the dynamics of genetic circuits that is tailored towards the unique properties associated with biological systems and experiments. Our framework approximates a complex circuit as a set of simpler circuits, which the system can transition between by saturating its various internal components. These approximations are connected to the intrinsic structure of the system, so this representation allows the analysis of dynamics which emerge solely from the system's structure. Using our framework, we analyze the presence of structural bistability in a leaky autoactivation motif and the presence of structural oscillations in the Repressilator

Development of Charter School Teacher Development Inventory

The aim of the present study was to develop and examine the initial psychometrics of an instrument, the Charter School Teacher Development Inventory (CSTDI), designed to measure the professional learning opportunities available in U.S. charter schools. Items on the CSTDI were derived from a review of relevant literature and were intended to gather information on how frequently U.S. charter schools employ traditional professional development methods and the five areas of more effective professional development (content focus, active learning, collaboration, coherence, and duration). The final form of the CSTDI was sent electronically to 6322 charter school administrators and 2428 returned completed surveys. Exploratory factor analysis performed on a randomly assigned half of the sample (n =1214) suggested that the CSTDI was comprised of five factors: traditional, content, coherence, duration, and active learning/collaboration. Confirmatory factor analysis was performed on the second half of the sample and provided additional support for a five factor structure of the CSTDI. Reliability coefficients for each of the five factors were above .90. This study provides promising support for a five-factor instrument that assesses professional development practices in charter schools. While the CSTDI was developed for use with charter school administrators, further research is warranted to determine if it may be relevant for use with teachers and administrators in both traditional public schools and charter schools

Nonlinear controllers for non-integrable systems: the Acrobot example

Recent developments in the theory of geometric nonlinear control provide powerful methods for controller design for a large class of nonlinear systems. Many systems, however, do not satisfy the restrictive conditions necessary for either full state linearization [6, 5] or input-output linearization with internal stability [2]. In this paper, we present an approach to controller design based on finding a linearizable nonlinear system that well approximates the true system over a desirable region. We outline an engineering procedure for constructing the approximating nonlinear system given the true system. We demonstrate this approach by designing a nonlinear controller for a simple mechanical system patterned after a gymnast performing on a single parallel bar

Asynchronous Distributed Averaging on Communication Networks

Distributed algorithms for averaging have attracted interest in the control and sensing literature. However, previous works have not addressed some practical concerns that will arise in actual implementations on packet-switched communication networks such as the Internet. In this paper, we present several implementable algorithms that are robust to asynchronism and dynamic topology changes. The algorithms are completely distributed and do not require any global coordination. In addition, they can be proven to converge under very general asynchronous timing assumptions. Our results are verified by both simulation and experiments on Planetlab, a real-world TCP/IP network. We also present some extensions that are likely to be useful in applications

Defining the Costs of an Outbreak of Karnal Bunt of Wheat

In determining the economic impact of a possible outbreak of the quarantinable wheat disease Karnal Bunt, an examination was made of the detailed components of the costs involved. The costs were classified as: (a) Direct costs (yield and quality losses); (b) Reaction costs (export bans, quality down-grading, seed industry costs); and (c) Control costs (quarantine zones, fungicides, spore destruction). The relative importance of each of these cost components is measured for a hypothetical outbreak of Karnal Bunt in the European Union, as a means of ensuring that the policy responses to such an outbreak are appropriate considering the costs involved.disease, quarantine, cost, wheat, Agricultural and Food Policy, Crop Production/Industries,

Lightweight Aggregate Potentialities of Some Indiana Shales

Indiana Geological Survey Report of Progress 12Laboratory tests show that some Indiana shales are potential sources of manufactured lightweight aggregate. Bloating, the process by which lightweight aggregates are manufactured, is caused by various constituents acting singly or in combination. Chemical composition and mineral composition of the shales and particle-size distribution of the mineral constituents are interrelated, and all of these factors contribute to the bloating of shales. This study was made to test the potential use of some Indiana, shales as raw materials for manufacturing lightweight aggregate. Such aggregate was produced in Ohio, Illinois, and Kentucky before any interest was shown in Indiana. A new plant is now producing lightweight aggregate from shale of the Borden group near Brooklyn, Ind., but other plants are needed to meet the increasing demand for lightweight concrete in the State. It is hoped that this report will stimulate interest in developing lightweight aggregate from shale and will enable future producers of lightweight aggregate in Indiana to evaluate better the location, thickness, extent, and physical properties of various shale formations.Indiana Department of Conservatio

Journal Article – Psychiatry in the Army Air Forces & The Services of the Military Mental Hygiene Unit

Two articles published in the July 1943 issue of the American Journal of Psychiatry that discuss the Special Training Unit Program. The titles are, Psychiatry in the Army Air Forces and The Services of the Military Mental Hygiene Unit.https://scholarworks.moreheadstate.edu/stu_1210th_fort_ontario/1056/thumbnail.jp