Fixed parameter tractability of crossing minimization of almost-trees

We investigate exact crossing minimization for graphs that differ from trees by a small number of additional edges, for several variants of the crossing minimization problem. In particular, we provide fixed parameter tractable algorithms for the 1-page book crossing number, the 2-page book crossing number, and the minimum number of crossed edges in 1-page and 2-page book drawings.Comment: Graph Drawing 201

Political Instability and Growth in Dictatorships

We model growth in dictatorships facing each period an endogenous probability of ``political catastrophe'' that would extinguish the regime's wealth extraction ability. Domestic capital exhibits a bifurcation point determining economic growth or shrinkage. With low initial domestic capital the dictator plunders the country's resources and the economy shrinks. With high initial domestic capital the economy eventually grows faster than is socially optimal.dictatorship, growth, political economy, bifurcation

A summary of research relating to reading in the intermediate grades

Purpose: To develop and evaluate a method of quick perception with geography vocabulary to see if; (a) quick perception accelerates growth in comprehension, (b) effects speed of reading, and (c) improves reading ability. Materials used: (1) Vocabulary selected from: a) Atwood, The Americas, b) McConnel, Living in the Americas, c) Smith, World Folk. (2) Durrell-Sullivan Achievement Tests, Intermediate Forms A and B. (3) Oral Reading Tests for Speed from the "Durrell Analysis of Reading Difficulty". (4) Silent Reading and Vocabulary Inventory Tests constructed by the writer. (5) Lantern slide projector; screen; words and phrases typed on amber cellphone, faced with red carbon paper, enclosed in glass slides, hinged with tape at the top [TRUNCATED

Full-field hard x-ray microscopy with interdigitated silicon lenses

Full-field x-ray microscopy using x-ray objectives has become a mainstay of the biological and materials sciences. However, the inefficiency of existing objectives at x-ray energies above 15 keV has limited the technique to weakly absorbing or two-dimensional (2D) samples. Here, we show that significant gains in numerical aperture and spatial resolution may be possible at hard x-ray energies by using silicon-based optics comprising 'interdigitated' refractive silicon lenslets that alternate their focus between the horizontal and vertical directions. By capitalizing on the nano-manufacturing processes available to silicon, we show that it is possible to overcome the inherent inefficiencies of silicon-based optics and interdigitated geometries. As a proof-of-concept of Si-based interdigitated objectives, we demonstrate a prototype interdigitated lens with a resolution of ~255 nm at 17 keV.Comment: 10 pages, 5 figure. Submitted to Applied Physics Letters 31st March 2015, rejected 17th June 201

Toward a Broader – But Still Rigorous – Definition of Leader Integrity: Commentary

[Excerpt] The impetus for this special issue of The Leadership Quarterly grew out of the desire of a small but enthusiastic group of leadership scholars who were interested in the concepts of integrity in general and behavioral integrity (the consistency between words and actions) in particular. Guest Editor Tony Simons\u27 (2002) theoretical article in Organization Science had sparked a great deal of interest in behavioral integrity, including the interest of a then-doctoral student at Binghamton University, Guest Editor Mike Palanski. Palanski was seeking advice for his dissertation, and Simons wished to build a cadre of scholars with an interest in leader behavioral integrity. A year or so later, Palanski had the “misfortune” of presenting a paper on integrity as the final presenter in the final session on the final day of the 2006 Academy of Management conference in Atlanta. To his surprise, the room was packed, and it quickly became clear that others also wished to study leader integrity in more depth

Auralization of novel aircraft configurations

A joint initiative of NLR, DLR, and TU Delft has been initiated to streamline the process of generating audible impressions of novel aircraft configurations. The integrated approach adds to the value of the individual tools and allows predicting the sound of future aircraft before they actually fly. Hence, an existing process for the aircraft design and system noise prediction at DLR has been upgraded to generate the required input data for an aircraft auralization framework developed by NLR and TU Delft. This paper presents the new process and an initial application towards the fully automated auralization of novel aircraft configurations within the conceptual aircraft design phase. Such an early auralization of the new designs enables the aircraft designer to assess the success of selected low-noise measures in an intuitive way in addition to the conventional measures, e.g. noise isocontour areas. The auralization result is able to capture all the predicted noise shielding measures used in the current application and indicates that, for an approach condition, drastically reduced ground noise exposure can be achieved

Flow-regulated lymphatic vasculature development and signaling

The role of blood flow in regulating signaling pathways and gene expression in the blood vasculature is well known. Recent studies have identified equally important roles of flow-mediated signaling in the lymphatic circulation including control of lymphatic vascular growth, remodeling, regeneration and maintenance of the lymphatic fate. In this review, we summarize these advances focusing on the role of fluid dynamics in control of lymphatic vasculature formation