On Interpretation of ESCA Spectra with Application to Thymine and Other Molecules

1s binding energies are calculated for nitrogen atoms in thymine, pyrrole, adenine, and pyridine and for carbon atoms in thymine, adenine, pyrrole, and furan, and compared with experimental values. Calculations are performed in the framework of a perturbational model using CNDO molecular wave functions. Interactions of the 1s electron with its own atom are calculated exactly whereas interactions with neighbor atoms are calculated according to two levels of approximation: (1) Point charge approximation. (2) Rigorous calculations of integrals. Magnitudes of the different interactions and integrals are analysed. The questions of assignments of ESCA shifts and the errors inherent in the calculations are discussed.     

Synergistic activity between a spinach-derived natural antioxidant (NAO) and commercial antioxidants in a variety of oxidation systems

Recently, there has been great interest in the potential health benefits of foods containing polyphenols, especially from plants, due to their antioxidant content. Natural antioxidant (NAO) is a unique, powerful antioxidant which was isolated in our lab from spinach leaves. The main goal of this study was to examine potential synergistic activity in combinations of NAO and commercial antioxidants. The antioxidant activity was tested in several in vitro systems including fatty acid and fat oxidation and also in cancer cell lines. We used the unique optical live cell array (LCA) technology to monitor the generation of reactive oxygen species (ROS) in single cells over time. NAO was combined with selected commercial antioxidants, and synergistic activity that reduced ROS generation was found with three polyphenols – ferulic acid, caffeic acid, and epigallocatechin-3-gallate (EGCG). These findings demonstrate the importance of using antioxidant ‘cocktails’ which may enhance medical effects in many kinds of diseases, including cardiovascular diseases and cancer.     

New evidence for phonological processing during visual word recognition: The case of Arabic.

Lexical decision and naming were examined with words and pseudowords in literary Arabic and with transliterations of words in a Palestinian dialect that has no written form. Although the transliterations were visually unfamiliar, they were not easily rejected in lexical decision, and they were more slowly accepted in phonologically based lexical decision. Naming transliterations of spoken words was slower than naming of literary words and pseudowords. Apparently, phonological computation is mandatory for both lexical decision and naming. A large frequency effect in both lexical decision and naming suggests that addressed phonology is an option for familiar orthographic patterns. The frequency effect on processing transliterations indicated that lexical phonology is involved with prelexical phonological computation even if addressed phonology is not possible. These data support a combination between a cascade-type process, in which partial products of the grapheme-to-phoneme translation activate phonological units in the lexicon, and an interactive model, in which the activated lexical units feed back, shaping the prelexical phonological computation process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention mechanisms mediate the syntactic priming effect in auditory word identification.

Investigated the syntactic priming effect and the involvement of attention in that process by testing identification of white noise-masked Hebrew words. Targets were either syntactically congruent or syntactically incongruent with the structure of the sentence. Relative to a neutral condition, similar facilitation and inhibition was found for congruent and incongruent targets, respectively. When syntactic congruency was blocked, the inhibition was attenuated, whereas the facilitation remained the same. A 350-msec silent interstimulus interval between context and target increased inhibition without affecting facilitation. It is suggested that both the facilitation and the inhibition effects of syntactic priming are based on a veiled controlled process of generating expectations. The inhibition results from a controlled process of reevaluation that requires additional attention resources. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The structure of attitudes toward persons with disabilities: An Israeli validation of Siller's Disability Factor Scales—General (DFS—G).

Investigated the transcultural generalizability of the Disability Factor Scales—General (DFS—G) of J. Siller et al (1967) in 658 Jewish Israeli 11th and 12th graders and undergraduates. All Ss filled out a Hebrew translation of the 69-item DFS—G. Factor analysis of the Ss' responses provided support for the replicability of a major part of the DFS—G's structure. Also, a subsample of 114 Ss was administered the Edwards Social Desirability Scale while a subsample of 197 Ss was administered the Marlowe-Crowne Social Desirability Scale. Correlations between some scales of the DFS—G and these 2 measures are discussed as possible evidence that attitudes toward disability may reflect defenses against intra- and interpersonal pressures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Antioxidant activity of 1,3-dicaffeoylquinic acid isolated from Inula viscosa

Inula viscosa is a perennial herbaceous plant used topically in folk medicine as an anti-scabies, anti-inflammatory, and wound-healing agent. We examined the antioxidant activity of the methanolic extract of I. viscosa. We isolated and identified several polyphenolic antioxidants from I. viscosa leaves and focused on 1,3-dicaffeoylquinic acid (1,3-diCQA). Antioxidant activity was measured using ABTS and DPPH assays, which measure antioxidant activity. The concentrations of 1,3-diCQA required for the inhibition of oxidation were lower than those required by other known antioxidants. 1,3-diCQA inhibited oxidative damage caused by various factors, including FeSO₄ and AAPH (2,2′-azobis(2-amidinopropane) dehydrochloride). Antioxidant activity can also be detected by the ability of a compound to scavenge reactive oxygen species (ROS). 1,3-diCQA was found to scavenge hydroxyl radical and superoxide radicals, as measured by electron spin resonance (ESR). These data demonstrate that 1,3-diCQA exhibits antioxidant properties, probably through the involvement of a direct scavenging effect on several free radicals.     

Sorption of propylene oxide by various commodities

Sorption of propylene oxide (PPO) by various commodities was studied at different concentrations during a 4-h exposure at 30 °C. A gas chromatograph was used to determine sorption of PPO applied at concentrations of 24, 49, 82 and 112 mg/l by 1±0.01 kg of narcissus bulbs, wheat, corn and cocoa beans in 2.64-l fumigation chambers. Results showed that for corn and cocoa beans the decrease in concentration during the first hour, that ranged from 40% to 76% of the initial concentration applied, was much greater than that for narcissus bulbs and wheat, which ranged from 25% to 41% of the initial concentration applied. PPO was initially taken up faster by corn and cocoa beans than by narcissus bulbs and wheat. The average sorption rate for each commodity increased with increasing initial concentration. The average sorption rate of PPO by corn and cocoa beans ranged from 14.9 to 48.6 ((mg/kg)/h) which was higher at each concentration than sorption by narcissus bulbs and wheat. In spite of the relatively high rates of sorption, the PPO residues among wheat, corn and cocoa beans immediately following a 4-h fumigation were well below the 300 ppm tolerance. These data show that PPO rapidly desorbed from the commodities under fumigation at 30 °C and at ambient atmospheric pressure.