In English the NP1 V NP2 construction typically involves arguments that are construed as Agent and Patient, or Subject Object. It is associated with notion of transitivity analyzed accordingly, even when it exhibits only syntactic properties but not its semantic characteristics. This phenomenon well-known has been accounted for by linguists (Lakoff 1977; Hopper Thompson 1980, among others) a re...

We consider variations on the classic video game Tetris where pieces are k-ominoes instead of the usual tetrominoes (k = 4), as popularized by the video games ntris and Pentris. We prove that it is NP-complete to survive or clear a given initial board with a given sequence of pieces for each k ≥ 5, complementing the previous NP-completeness result for k = 4. More surprisingly, we show that boar...

The dimension of a partial order P is the minimum number of linear orders whose intersection is P . There are efficient algorithms to test if a partial order has dimension at most 2. In 1982 Yannakakis [24] showed that for k ≥ 3 to test if a partial order has dimension ≤ k is NP-complete. The height of a partial order P is the maximum size of a chain in P . Yannakakis also showed that for k ≥ 4...

The question of whether the complexity class P is equal to the complexity class NP has been a seemingly intractable problem for over 4 decades. It has been clear that if an algorithm existed that would solve the problems in the NP class in polynomial time then P would equal NP. However, no one has yet been able to create that algorithm or to successfully prove that such an algorithm cannot exis...

The human immunodeficiency virus (HIV)-Tat protein has been implicated in the neuropathogenesis of HIV infection. However, its role in modulating astroglial function is poorly understood. Astrocyte infection with HIV has been associated with rapid progression of dementia. Intracellularly expressed Tat is not toxic to astrocytes. In fact, intracellularly expressed Tat offers protection against o...

OBJECTIVES 3-Nitropropionic acid (3-NP), an irreversible inhibitor of succinate dehydrogenase, has been shown to protect against ischemic injury in the brain and in the heart via a preconditioning-like effect; however, the cellular mechanism is not known. The aim of the present study was to investigate if 3-NP pretreatment reduces infarct size and if altered metabolism of nitric oxide and react...

It is a well-known result of Fagin that the complexity class NP coincides with the class of problems expressible in existential second-order logic (1 ;). Monadic NP is the class of problems expressible in monadic Z;, i.e., 1: with the restriction that the second-order quantifiers range only over sets (as opposed to ranging over, say, binary relations). We prove that connectivity of finite graph...

PURPOSE The integrin αvβ3 is differentially expressed on neovascular endothelial cells. We investigated whether a novel intravenously injectable αvβ3 integrin-ligand coupled nanoparticle (NP) can target choroidal neovascular membranes (CNV) for imaging and targeted gene therapy. METHODS CNV lesions were induced in rats using laser photocoagulation. The utility of NP for in vivo imaging and ge...