34 research outputs found
On Second-Order Monadic Monoidal and Groupoidal Quantifiers
We study logics defined in terms of second-order monadic monoidal and
groupoidal quantifiers. These are generalized quantifiers defined by monoid and
groupoid word-problems, equivalently, by regular and context-free languages. We
give a computational classification of the expressive power of these logics
over strings with varying built-in predicates. In particular, we show that
ATIME(n) can be logically characterized in terms of second-order monadic
monoidal quantifiers
Pine cone scale-inspired motile origami
Stimuli-sensitive hydrogels have received attention because of their potential applications in various fields. Stimuli-directed motion offers many practical applications, such as in drug delivery systems and actuators. Directed motion of asymmetric hydrogels has long been designed; however, few studies have investigated the motion control of symmetric hydrogels. We designed a pine cone scale-inspired movable temperature-sensitive symmetric hydrogel that contains Fe3O4. Alignment of Fe3O4 along the magnetic force is key in motion control in which Fe3O4 acts like fibers in a pine cone scale. Although a homogeneous temperature-sensitive hydrogel cannot respond to a temperature gradient, the Fe3O4-containing hydrogel demonstrates considerable bending motion. Varying degrees and directions of motion are easily facilitated by controlling the amount and alignment angle of the Fe3O4. The shape of the hydrogel layer also influences the morphological structure. This study introduced facile and low-cost methods to control various bending motions. These results can be applied to many fields of engineering, including industrial engineering.111Ysciescopu
Interaction of milk proteins and Binder of Sperm (BSP) proteins from boar, stallion and ram semen
Interaction of Fibronectin Type II Proteins with Membranes: The Stallion Seminal Plasma Protein SP-1/2
Block Products and Nesting Negations in FO2
The alternation hierarchy in two-variable first-order logic FO 2 [â < â] over words was recently shown to be decidable by Kufleitner and Weil, and independently by Krebs and Straubing. In this paper we consider a similar hierarchy, reminiscent of the half levels of the dot-depth hierarchy or the Straubing-ThĂ©rien hierarchy. The fragment of FO 2 is defined by disallowing universal quantifiers and having at most mâ-â1 nested negations. One can view as the formulas in FO 2 which have at most m blocks of quantifiers on every path of their parse tree, and the first block is existential. Thus, the m th level of the FO 2 -alternation hierarchy is the Boolean closure of. We give an effective characterization of, i.e., for every integer m one can decide whether a given regular language is definable by a two-variable first-order formula with negation nesting depth at most m. More precisely, for every m we give Ï-terms U m and V m such that an FO 2 -definable language is in if and only if its ordered syntactic monoid satisfies the identity U m âV m. Among other techniques, the proof relies on an extension of block products to ordered monoids. © 2014 Springer International Publishing Switzerland