The basic components of any speciication language include: constructs for specifying the properties of individual program components such as types and functions; structuring mechanisms for building large speciications in a modular fashion; a description of the semantics of the language; mechanisms for performing proofs of properties of speciications; a notion of reenement of speciications; and ...

A speci cation slice is a projection of a formal speci cation, which is simpler and potentially more comprehensible than the original speci cation. A static speci cation slice contains speci cations that might restrict the value of a variable. A dynamic speci cation slice consists of speci cations that actually a ect the value of a variable along the sequence of operations performed. Dynamic sp...

The purifi cation of a valuable product or product library after a long and complex synthesis is a very important process. The Agilent Automated Purifi cation Software introduces an Open-Access-based solution for isolating substances, with automated focused gradient to simplify the preand post-purifi cation steps. This Technical Overview describes the easy steps to follow, from crude sample ana...

A novel fluorescent chemodosimeter based on 1,8-naphthyridine exhibits high selectivity to Zn(2+) and Cu(2+). When 1-(7-acetamino-1,8-naphthyridyl)-2-(6-diacetaminopyridyl)ethene was mixed with CuCl2, hydrolysis of the acetamino group catalyzed by Cu(2+) complex was first observed. Resulting from coordination and hydrolysis catalyzed by the corresponding complex of Zn(2+) or Cu(2+), the highly ...

Five Pt(II) complexes were tested for their ability to interfere in Cu(II) or Zn(II) coordination to the Aβ peptide. Two of them induce modifications of the Cu(II) sphere but not the associated Cu(Aβ) ROS production. In contrast, they do completely preclude Zn induced Aβ aggregation.

Cation exchange capacity (CEC) is one of the most important soil attributes which control some basic properties of soil such as acidity, water and nutrient retaining capacity. However, the measurement of cation exchange capacity in large areas is time consuming and requires high expenses. One way to save time and expenses is to use simple soil covariates and geostatistical methods in mapping CE...

The aim of this study was to develop an extended-release tablet formulation using a new in situ cross-linking method. The effects of polyvalent cations on theophylline release from tablets made with the polyanionic polymers sodium alginate and sodium carboxymethylcellulose, were investigated. Different miliequivalents of the di and tri-valent cation, Ca2+ and Al3+, were added to tablet form...

Introduction: Previous studies and our works have indicated several cation channels in the rat brain mitochondrial inner membrane. In this work, we report the single-channel characterization of a cation channel from the rat brain mitochondrial inner membrane incorporated into a planar lipid bilayer. Methods: After removing and homogenizing the adult rat brain, its supernatant was centrifuged...

The mechanism by which bi-and trivalent cations affect human liver phosphatidatephosphohydrolase (PAP) activity was investigated. Bivalent cations up to 1 mM increased PAP activity whereas at higher concentrations the activity of the enzyme decreased. The stimulatory concentration for trivalent cations such as Al3+ and Cr3+, however, was much lower being 2 m M and 1 m M, respectively. All catio...

We study the classi cation of recursive predicates and languages. In particular, we compare the classi cation of predicates and languages with the classi cation of arbitrary recursive functions and with learning. Moreover, we re ne our investigations by introducing classi cation with a bounded number of mind changes and establish a new hierarchy. Furthermore, we introduce multi{classi cation an...