Cross-validation of the ability of the Luria-Nebraska Neuropsychological Battery to differentiate chronic schizophrenics with and without ventricular enlargement.

33 of 43 chronic schizophrenic patients (aged 20–39 yrs) were correctly classified by the Luria-Nebraska Neuropsychological Battery for the presence or absence of ventricular enlargement, as assessed by computer tomography (CT) scan. Results are comparable to those of an earlier study by C. G. Golden et al (see record 1981-29339-001). Differences between the studies and the implications of objective CT scan measurement for detecting cerebral atrophy are discussed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The dynamics of the imprinted H19 gene expression in the mouse model of bladder carcinoma induced by N-butyl-N-(4-hydroxybutyl)nitrosamine

The imprinted H19 gene product is an oncofetal RNA molecule in humans. It is expressed in fetal bladder, down-regulated postnatally and is re-expressed in human bladder carcinoma. This study was designed to investigate the dynamics of the expression of H19 in the mouse bladder carcinoma induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) and its relation to stages of neoplastic transformation. BBN was administered to mice in the drinking water for 26-28 weeks. The bladders were removed at 5-10 week intervals for histopathological examination and for in situ hybridization for H19 RNA, using a 35S-labeled probe. Following BBN administration expression of H19 first appeared after 5 weeks in the lamina propria adjacent to the basement membrane, concomitant with mucosal hyperplasia. At 11 weeks focal expression was noted in epithelial cells. Invasive carcinomas, of the transitional and squamous sub-types, were seen after 20 weeks and more of BBN administration. At this stage H19 expression was observed in scattered tumor cells, in the connective tissue stroma of the tumor and in the lamina propria underlying the remaining hyperplastic/dysplastic mucosa. Abundant expression of H19 was evident in fetal bladder but was absent in normal adult bladder. We conclude that, similar to humans, the H19 gene product is an oncofetal RNA molecule in the experimental mouse model of bladder carcinoma. In this model H19 is expressed in the connective tissue of the lamina propria prior to its expression in epithelial cells, concurrent with preneoplastic changes in the transitional epithelium of the bladder.     

Specifying and analyzing early requirements in Tropos

We present a framework that supports the formal verification of early requirements specifications. The framework is based on Formal Tropos, a specification language that adopts primitive concepts for modeling early requirements (such as actor, goal, and strategic dependency), along with a rich temporal specification language. We show how existing formal analysis techniques, and in particular model checking, can be adapted for the automatic verification of Formal Tropos specifications. These techniques have been implemented in a tool, called the T-Tool, that maps Formal Tropos specifications into a language that can be handled by the NuSMV model checker. Finally, we evaluate our methodology on a course-exam management case study. Our experiments show that formal analysis reveals gaps and inconsistencies in early requirements specifications that are by no means trivial to discover without the help of formal analysis tools.

Nucleosome conformational flexibility and implications for chromatin dynamics

The active role of chromatin in the regulation of gene activity seems to imply a conformational flexibility of the basic chromatin structural unit, the nucleosome. This review is devoted to our recent results pertaining to this subject, using an original approach based on the topology of single particles reconstituted on DNA minicircles, combined with their theoretical simulation. Three types of chromatin particles have been studied so far: a subnucleosome, that is, the (H3-H4)(2) histone tetramer-containing particle, now known as the tetrasome; the nucleosome; and the linker histone H5/H1-bearing nucleosome (the chromatosome). All the particles were found to exist in two to three conformational states, which differ by their topological and mechanical properties. Our approach unveiled the molecular mechanisms of nucleosome conformational dynamics and will help to understand its functional relevance. A most surprising conclusion of the work was perhaps that DNA overall flexibility increases considerably upon particle formation, which might indeed be a requirement of genome function.     

The flow of an elastico-viscous fluid past a stretching sheet with partial slip

Summary An analysis is carried out to study the flow characteristics in an elastico-viscous fluid (Walters' liquid-B model) over a stretching sheet with partial slip. The flow is generated due to linear stretching of the sheet. Using suitable similarity transformations on the highly non-linear partial differential equations we derive exact analytical solution with appropriate boundary conditions. The important finding in this communication is the effect of partial slip on the velocity and skin friction coefficient.     

Abilities, motives, and personal styles: Reply.

Responds to the comments of P. L. Ackerman (see record 2006-12925-012), D. Y. Dai (see record 2006-12925-013), and M. C. Gridley (see record 2006-12925-014) on E. S. Spelke's original article "Sex differences in intrinsic aptitude for mathematics and science? A critical review" (see record 2005-15840-001). Here, the current authors first consider Ackerman's criticism of IQ measures of cognitive sex differences, as well as his suggestion that Advanced Placement tests be used as a second measure. Next, the authors discuss Dai's suggestion that cognition and motivation, abilities and strategies, are inseparably bound in any meaningful measure of aptitude for mathematics and science. Finally, the authors address Gridley's suggestion that differences in men's and women's thinking styles and preferences explain gender disparities in math and science fields. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Silane‐modified PVC pervaporation membranes for bromoform/water separation

The transport properties of a unique family of silane‐modified poly(vinyl chloride) (PVC) pervaporation membranes for the separation of halogenated hydrocarbons from water were investigated. The PVC was modified by using a vinyl silane to improve its resistance to attack by halogenated hydrocarbons and to increase the flux. Two preparation routes were used: Route i included an initiator to promote the vinyl reaction before the hydrolysis and condensation of the methoxy silane group, whereas Route ni did not. The structures of the membranes were characterized and related to the transport properties, as derived from batch pervaporation experiments. The permeability of unmodified PVC membranes increases with exposure to haloorganics at low concentrations. Initially, the modified membranes exhibited a higher permeability than PVC and a lower selectivity. At long pervaporation times, the silane‐modified membranes exhibited a higher selectivity than PVC. The different preparation routes led to different morphologies, which affected the performance of the membranes; Route ni membranes exhibited higher permeabilities and selectivity than Route i membranes. Rubbery polydimethylsiloxane membranes were resistant to haloorganics but their high water permeability and low selectivity make them unsuitable for this pervaporative separation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1429–1438, 2001     

Development and validation of a simple analytical method for the determination of 2,4,6-trichloroanisole in wine by GC–MS

A novel method for the residue analysis of wine spoilage compound 2,4,6-trichloroanisole is reported. Wine (60 ml) was extracted with 2 ml toluene in presence of 24 g MgSO₄ and 6 g NaCl. Cleanup of the toluene phase by dispersive solid phase extraction with mixture of 100 mg CaCl₂, 25 mg primary secondary amine and 50 mg MgSO₄ was effective in minimising co-extractives and matrix effects. Time-of-flight and tandem mass spectrometric parameters were optimised to achieve linearity over 0.25–500 ng ml⁻¹ and method detection limit 0.0083 ng ml⁻¹ which is well below the odour threshold of 0.04 ng ml⁻¹. Recoveries at 0.04, 0.2 and 0.8 ng ml⁻¹ were within 80–110% (±8%). The method was reproducible when tested for Argentinean wines with intra-laboratory Horwitz ratios being <0.20 in white and red wines at both the laboratories of India and Argentina. The method could be successfully applied for incurred wine samples.     

Effect of roasting conditions on the antioxidant compounds of quinoa seeds

The effect of different roasting conditions on the antioxidant properties and the phenolic content of quinoa seeds was studied. Advanced and final products of the Maillard reaction were also quantified in order to evaluate the contribution to DPPH radical scavenging capacity and reducing power of samples. In general, response surface analysis showed significant increases in the phenolic content, the antioxidant activity and the level of Maillard reaction products (MRPs), mainly as processing temperature increased, while roasting time had a minor impact on these response variables. The highest antioxidant activity was achieved in extracts of quinoa seeds roasted at 190 °C for 30 min. Principal component analysis applied to the data suggested that MRPs had a greater contribution to antioxidant properties than phenolic compounds in the processed samples. These results demonstrated that roasted quinoa seeds/flour may be considered as a nontraditional ingredient with enhanced antioxidant capacity for the production of functional foods.