Equivalence of the filament and overlap graphs of subtrees of limited trees

The overlap graphs of subtrees of a tree are equivalent to subtree filament graphs, the overlap graphs of subtrees of a star are cocomparability graphs, and the overlap graphs of subtrees of a caterpillar are interval filament graphs. In this paper, we show the equivalence of many more classes of subtree overlap and subtree filament graphs, and equate them to classes of complements of cochordal-mixed graphs. Our results generalize the previously known results mentioned above

Pathways to Grow Impact: Philanthropy's Role in the Journey

Since 2010, through the "Scaling What Works" initiative, GEO has fostered a conversation about scale that considers a variety of ways nonprofits are creating more value for communities and how funders are supporting their work. GEO's newest publication, "Pathways to Grow Impact", shares new learning about the role grantmakers should play. The publication is the result of a collaborative project with Ashoka, Social Impact Exchange, Taproot Foundation and TCC Group that sought to answer the question: How can grantmakers best support high-performing nonprofits in their efforts to grow their impact? "Pathways to Grow Impact" is for any grantmaker who wants his or her grant dollars to have a greater effect. The publication offers a framework for understanding different approaches to scaling impact, stories from nonprofit leaders who have successfully grown their organizations' impact, and practical recommendations for grantmakers seeking more effective ways to achieve better results

When the beachhopper looks at the moon: The moon compass hypothesis

The function of moon position for shoreline orientation by talitrids is investigated. Three major results were found: (1) Observed cases of compensation for changes in the direction of the moon are based on physiological rhythm with a period of about 25 hours which can persist for at least several days under constant conditions. (2) The zeitgeber for physiological rhythm may be either moonlight or some other factor associated with the tides. (3) If talitrids are long removed from environmental entrainment, either artifically or naturally, the internal rhythm no longer exerts an appreciable influence on the angle of lunar orientation; in such cases the system deteriorates into constant angle orientation, with an angle which is determined by the beach orgin, but may be modified by lighting conditions

Paradoxical monocular stereopsis and perspective vergence

The question of how to most effectively convey depth in a picture is a multifaceted problem, both because of potential limitations of the chosen medium (stereopsis, image motion), and because effectiveness can be defined in various ways. Practical applications usually focus on information transfer, i.e., effective techniques for evoking recognition of implied depth relationships, but this issue depends on subjective judgements which are difficult to scale when stimuli are above threshold. Two new approaches to this question are proposed here which are based on alternative criteria for effectiveness. Paradoxical monocular stereopsis is a remarkably compelling impression of depth which is evoked during one-eyed viewing of only certain illustrations; it can be unequivocally recognized because the feeling of depth collapses when one shifts to binocular viewing. An exploration of the stimulus properties which are effective for this phenomenon may contribute useful answers for the more general perceptual problem. Positive vergence is an eye-movement response associated with changes of fixation point within a picture which implies depth; it also arises only during monocular viewing. The response is directionally appropriate (i.e., apparently nearer objects evoke convergence, and vice versa), but the magnitude of the response can be altered consistently by making relatively minor changes in the illustration. The cross-subject agreement in changes of response magnitude would permit systematic exploration to determine which stimulus configurations are most effective in evoking perspective vergence, with quantitative answers based upon this involuntary reflex. It may well be that most effective pictures in this context will embody features which would increase effectiveness of pictures in a more general sense

Periodicity in wide-band time series

Summary: To test the hypotheses that (i) electroencephalograms (EEGs) are largely made up of oscillations at many frequencies and (ii) that the peaks in the power spectra represent oscillations, we applied a new method, called the Period Specific Average (PSA) to a wide sample of EEGs. Both hypotheses can be rejected

The Eight: An Art Movement

In lieu of an abstract, below is the essay\u27s first paragraph.The movement of the early 1900s known as the Eight was an important cultural movement for the world of art, exhibitions, and individual artists alike. Although the Eight weren\u27t as massively revolutionary as they would have liked to be, they were a very effective tool to spark change in the art scene at the time. They were nonconformist painters who helped to pave the way for the rise of private art exhibitions and the power of the artist as an individual