We consider the problem of determining the maximum and the minimum number of upward planar orientations a maximal planar graph can have. We show that n-vertex maximal planar graphs have at least Ω(n · 1.189) and at most O(n · 4) upward planar orientations. Moreover, there exist n-vertex maximal planar graphs having as few as O(n · 2) upward planar orientations and n-vertex maximal planar graphs...

The authors propose that individuals transitioning to a novel environment will prefer upward comparisons, particularly those made with individuals who have experienced a similar transition. Such comparisons help to reduce uncertainty and demonstrate that future success is possible. Study 1 found that individuals facing transitions to unfamiliar situations seek upward comparisons as a result of ...

Context: Glenohumeral and scapular upward rotation are important factors in functional upper extremity motion. Objectives: To determine how different amounts of glenohumeral rotation (internal, external, and neutral) affect scapular upward rotation. Design: Controlled laboratory study. Independent variables were the amounts of internal, external, and neutral glenohumeral rotation. The dependent...

Three studies show that different forms of self-activation have differential influences on the processing of social comparison information. Activating neutral self-conceptions results in defensive processing of threatening social comparison information (Study 1). Participants maintain favorable self-evaluations in the face of upward comparison and rate the upward target of comparison negatively...

In this paper we consider the problem of characterizing the directed graphs that admit an upward straight-line embedding into every point set in convex or in general position. In particular, we show that no biconnected directed graph admits an upward straight-line embedding into every point set in convex position, and we provide a characterization of the Hamiltonian directed graphs that admit u...

PURPOSE We developed an inverse technique for tissue morcellation by modifying the conventional upward technique and then examined its safety and efficiency. MATERIALS AND METHODS From July 2008 to December 2010, a total of 389 consecutive patients treated with holmium laser enucleation of the prostate (HoLEP) were enrolled in this study. For tissue morcellation, we used an upward technique f...

In this paper, we investigate planar upward straight-line grid drawing problems for bounded-degree rooted trees so that a drawing takes up as little area as possible. A planar upward straight-line grid tree drawing satisses the following four constraints: (1) all vertices are placed at distinct grid points (grid), (2) all edges are drawn as straight lines (straight-line), (3) no two edges in th...

Recent increases in the use of hydraulic fracturing (HF) to aid extraction of oil and gas from black shales have raised concerns regarding potential environmental effects associated with predictions of upward migration of HF fluid and brine. Some recent studies have suggested that such upward migration can be large and that timescales for migration can be as short as a few years. In this articl...