An efficient and convenient synthesis of novel tetrahydrobenzo[c]acridin-8(7H)-one derivatives is described using the electrogenerated anion of acetonitriles as the base in the presence of tetrabutylammonium fluoride as an effective supporting electrolyte in a one-pot, three-component condensation of aromatic aldehyde, dimedone and 1-naphthyl amine. The reaction is carried out in an undivided c...

There are formal proof systems other than Hilbert-style for classical logic, whether propositional, first-order, or higher-order. Among these alternatives are tableaux, Gentzen, and natural deduction systems. None of these are discussed in Enderton’s book. In a Hilbert system, finding a derivation for a wff may be a tricky business, as one has to guess which axiom and which inference rule to us...

The present study was an attempt to investigate the washback effect of the TEFL MA University Entrance Exam on the teaching and learning behaviors of students and professors. The TEFL MA UEE consists of three sub-components that deal with particular aspects of applied linguistics; each of these parts measures the participants’ knowledge in linguistics, language testing, and teaching methodology...

The ball milling of powders is a non-equilibrium technique (similar to rapid solidification processes) that can be used for production and structural modification of materials. Carbon nanotubes (CNTs) are relatively new materials with excellent combination of properties. They are one of the advanced reinforcement materials for engineering composites. Besides the polymer and ceramic matrices, in...

Gnetales comprise three unusual genera of seed plants, Ephedra, Gnetum, and Welwitschia. Their extraordinary morphological diversity suggests that they are survivors of an ancient, more diverse group. Gnetalean antiquity is also supported by fossil data. Dispersed "ephedroid" (polyplicate) pollen first appeared in the Permian >250 million years ago (Myr), and a few megafossils document the pres...

This study examined trends in stimulant use and attitudes toward use among American collegiate hockey athletes. All 139 players in one college hockey conference completed a comprehensive questionnaire. Over half of the athletes (51.8%) confirmed stimulant use before a hockey game or practice. About half of the respondents (48.5%) reported having used ephedra at least one time to improve athleti...

Ephedra-containing dietary supplements are consumed to improve sports performace, but may carry risks of cardiac and neurological adverse events. Little is known of their use by young athletes. Our aim was to determine the prevalence and patterns of ephedra use among high school athletes. An anonymous survey was performed in Rochester, Minnesota on high school athletes who participated in fall ...

We investigate how information leakage reduces computational entropy of a random variable X. Recall that HILL and metric computational entropy are parameterized by quality (how distinguishable is X from a variable Z that has true entropy) and quantity (how much true entropy is there in Z). We prove an intuitively natural result: conditioning on an event of probability p reduces the quality of m...

In this study, calcium-phosphate (Ca-P) and graphene oxide (GO)/ calcium-phosphate (Ca-P) coatings were electrodeposited with different pulsed current densities on TiO2 nanotubes. Results showed that the co-electrodeposition rate in the presence of GO, especially at low current densities of 2 and 5 mA/cm2, significantly decreased. This might be due to the large size of GO sheets as compared to ...