Alternative Paradigms for Structuring Collegiate Flight Programs

Collegiate aviation programs traditionally have been modeled on industry flight training programs, as exemplified by the U. S. Military and the airlines industry. Recently university administrators have been urging a shift in such programs to a more conventional academic paradigm where faculty are required hold doctoral degrees and to publish regularly. Such a transition may not succeed for a number of reasons, including the fact that faculty in aviation programs with extensive experience flying heavy aircraft typically do not hold the PhD degree and often have little or no interest in publishing scholarly papers. At the same time, the need to conduct funded research in aviation universities cannot be ignored. A possible solution to these contradictions lies in allowing some faculty in collegiate programs to teach and provide service to the university, which encouraging others so inclined to accept reduced teaching and service loads in exchange for pursuing funded research grants

Dynamic Institutionalization of the Terms of Presentation in Information Technology Management

This report of research in progress describes a study of how senior executives incorporate statements concerning information technology innovation into their public representations of firm performance, activities, and direction. Drawing on institutional theory and using longitudinal content analysis, we consider how discourse in the wider business milieu potentially shapes and constrains executives\u27 representations

MS 030 Guide to L. Rodney Rodgers, MD Papers (1940-1994)

The L. Rodney Rodgers, MD papers consists of announcements, correspondence, articles, handbooks, ethics papers, Harris County Medical society meeting records, reprints and other printed material related to L. Rodney Rodgers career in internal medicine. See more at MS 030

A Population Study of Euglena Gracilis Var. Urophora As Affected By Certain Carcinogenic Agents

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Finding Paths in the Rotation Graph of Binary Trees

A binary tree coding scheme is a bijection mapping a set of binary trees to a set of integer tuples called codewords. One problem considered in the literature is that of listing the codewords for n-node binary trees, such that successive codewords represent trees differing by a single rotation, a standard operation for rebalancing binary search trees. Then, the codeword sequence corresponds to an Hamiltonian path in the rotation graph Rn of binary trees, where each node is labelled with an n-node binary tree, and an edge connects two nodes when their trees differ by a single rotation. A related problem is finding a shortest path between two nodes in Rn, which reduces to the problem of transforming one binary tree into another using a minimum number of rotations. Yet a third problem is determining properties of the rotation graph. Our work addresses these three problems. A correspondence between n-node binary trees and triangulations of (n+2)-gons allows labelling nodes of Rn, with triangulations, where adjacent triangulations differ by a single diagonal flip. It has been proven, using properties of triangulations, that Rn is Hamiltonian, and that its diameter is bounded above by 2n-6 for n ≥ 11. In Chapter Three we use triangulations to show that the radius of Rn, is n-1; to characterize the n+2 nodes in the center; to show that Rn is the union of n+2 copies of Rn-1; and to prove that Rn is (n-1)-connected. We also introduce the skeleton graph RSn of Rn, and give additional properties of both graphs. In Chapter Four, we give an algorithm, OzLex, which, for each of many different coding schemes, generates 2n-1 different sequences of codewords for n-node binary trees. We also show that, for every n ≥ 4, all such sequences combined represent 2n Hamiltonian paths in Rn. In Appendix Two, we modify OzLex to create TransOx, an algorithm which generates (n+2)2n sequences of codewords from a single coding scheme, and prove that, for n ≥ 5, the sequences represent (n+2)2n-1 Hamiltonian paths. The distance between extreme nodes in Rn is the diameter of the graph. In Chapter Five, we give properties of extreme nodes in terms of their corresponding triangulations; Appendix One contains additional related information. We present two heuristics, based on flipping diagonals, that find a path between two nodes in Rn: Findpath-1, in O(n log n) time; and FindPath-2, in 0(n2 log n) time. Each computes paths with less than twice the minimum length. We also identify a class of triangulation pairs where Findpath-2 significantly outperforms FindPath-1

A Procedure for Determining the Relative Volume of Mitochondria in Hepatic Cells

About forty years ago Cowdry\u27s monograph on mitochondria appeared evaluating the work of previous investigators, indicating synonymy and, in a sense, bringing the first exploratory phase of the study of these cellular constituents to a close (1). Reasonably specific methods for their demonstration had been devised, and it was possible to have some confidence in the conclusions that the so-called mitochondria of different kinds of cells, despite dissimilarities in size or shape, were comparable cellular parts

Incorporating comorbidity within risk adjustment for UK pediatric cardiac surgery

INTRODUCTION: When considering early survival rates after pediatric cardiac surgery it is essential to adjust for risk linked to case complexity. An important but previously less well understood component of case mix complexity is comorbidity. METHODS: National congenital heart diseases audit (NCHDA) data representing all pediatric cardiac surgery procedures undertaken in the United Kingdom and Ireland between 2009 and 2014 was used to develop and test groupings for comorbidity and additional non procedure based risk factors within a risk adjustment model for 30-day mortality. A mixture of expert consensus based opinion and empiric statistical analyses were used to define and test the new comorbidity groups. RESULTS: The study dataset consisted of 21,838 pediatric cardiac surgical procedure episodes in 18,834 patients with 539 deaths (raw 30-day mortality rate 2.5%). In addition to surgical procedure type, primary cardiac diagnosis, univentricular status, age, weight, procedure type (bypass, non-bypass or hybrid) and era, the new risk factor groups of: non Downs congenital anomalies, acquired comorbidities, increased severity of illness indicators (such as pre-operative mechanical ventilation or circulatory support) and additional cardiac risk factors (such as heart muscle conditions and raised pulmonary arterial pressure) all independently increased the risk of operative mortality. DISCUSSION: In an era of low mortality rates across a wide range of operations, non-procedure based risk factors form a vital element of risk adjustment and their presence leads to wide variations in the predicted risk of a given operation

Supersymmetry and a Time-Dependent Landau System

A general technique is outlined for investigating supersymmetry properties of a charged spin-\half quantum particle in time-varying electromagnetic fields. The case of a time-varying uniform magnetic induction is examined and shown to provide a physical realization of a supersymmetric quantum-mechanical system. Group-theoretic methods are used to factorize the relevant Schr\"odinger equations and obtain eigensolutions. The supercoherent states for this system are constructed.Comment: 47 pages, submitted to Phys. Rev. A, LaTeX, IUHET 243 and LA-UR-93-20

Depths and Thermal Habitat Used by Large versus Small Northern Pike in Three Minnesota Lakes

We monitored depths and temperatures used by large (>71‐cm) versus small Northern Pike Esox lucius in three north‐central Minnesota lakes with either acoustic telemetry or archival tags. Individual Northern Pike demonstrated flexibility in depths used within a season and between years. The fish had some tolerance for low levels of dissolved oxygen (<3 mg/L), but depth selection was generally constrained by low dissolved oxygen in summer and winter. The fish more fully exploited all available depths during winter and thermal turnover periods. During July and August, large Northern Pike tended to follow the thermocline into cooler water as upper water layers warmed. Selection ratios indicated that large Northern Pike preferred water temperatures of 16–21°C during August when temperatures up to 28°C were available. In two lakes providing dense overhead cover from water lilies in shallow water, small Northern Pike used warmer, shallower water compared with large fish during summer. In a third lake providing no such cover, small fish were more often in deeper, cooler water. For small Northern Pike, temperature seemed to be a secondary habitat consideration behind the presence of shallow vegetated cover. This study provided detailed temperature selection information that will be useful when considering temperature as an ecological resource for different sizes of Northern Pike.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141595/1/tafs1629.pd