The populations of light-demanding trees that dominate the canopy of central African forests are now aging. Here, we show that the lack of regeneration of these populations began ca. 165 ya (around 1850) after major anthropogenic disturbances ceased. Since 1885, less itinerancy and disturbance in the forest has occurred because the colonial administrations concentrated people and villages along...

Losing Chess is a chess variant where each player tries to lose all one’s pieces. As the naming of “Giveaway” variants has multiple schools of terminology, we state for definiteness that captures are compulsory (a player with multiple captures chooses which to make), a King can be captured like any other piece, Pawns can promote to Kings, and castling is not legal. There are competing rulesets ...

Path openings and closings are algebraic morphological operators using families of thin and oriented structuring elements that are not necessarily perfectly straight. These operators are naturally translation invariant and can be used in filtering applications instead of operators based on the more standard families of straight line structuring elements. They give similar results to area or att...

Network connectivity is usually addressed for convex domains where a direct line of sight exists between any two transmitting/receiving nodes. Here, we develop a general theory for the network connectivity properties across a small opening, rendering the domain essentially non-convex. Our analytic approach can go only so far as we encounter what is referred to in statistical physics as quenched...

double pylorus (dp) is a rare condition characterized by the presence of two openings from the gastric antrum to the duodenal bulb, which may be congenital or acquired. herein, we describe a case of dp in a cirrhotic patient.

We report a new type of holographic interface, which is able to manipulate the three fundamental properties of light (phase, amplitude, and polarization) over a broad wavelength range. The design strategy relies on replacing the large openings of conventional holograms by arrays of subwavelength apertures, oriented to locally select a particular state of polarization. The resulting optical elem...

‘Openings’ are strategies for playing the beginning of a game, and are often described as sequences of low-level actions (as in chess, for example). This makes it easy to query a database of recorded games for useful information, such as an opening’s success rate, popularity, and more. ‘Tactical shooters’ are video games featuring pseudo-realistic tactical simulations. Here, openings are conven...

AI has had notable success in building highperformance game-playing programs to compete against the best human players. However, the availability of fast and plentiful machines with large memories and disks creates the possibility of a game. This has been done before for simple or relatively small games. In this paper, we present new ideas and algorithms for solving the game of checkers. Checke...

study and characterization of unliganded openings is of central significance for the elucidation of gating mechanisms for allosteric ligand-gated ion channels. Unliganded openings have been reported for many channel types, but their low open probability can make it difficult to study their kinetics in detail. Because the large conductance calcium-activated potassium channel mSlo is sensitive to...