Roles of approval motivation and social reinforcement in children's discrimination learning.

144 3rd- and 4th-grade children were given a 2-choice discrimination learning task. The 2 major factors were (a) the 3 levels of social desirability (high, moderate, and low) on the Children's Social Desirability scale; and (b) the 2 types of treatment conditions (monetary-social reinforcement and monetary-no social reinforcement). In opposition to D. P. Crowne and D. Marlowe's (1961) model of the approval-motivated individual, the high-social-desirability group made significantly fewer errors than both the moderate and low groups. It is suggested that for young children, social desirability scores may require a different interpretation than scores for older children and adults. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Factors affecting DNA sequence selectivity of nogalamycin intercalation: the crystal structure of d(TGTACA)2-nogalamycin2

As part of an investigation into the sequence selectivity of the nogalamycin-DNA interaction, the 1.58 A structure of nogalamycin complexed with d5'(TGTACA)2 has been determined by single-crystal X-ray analysis. The complex crystallised in the orthorhombic space group P2(1)2(1)2(1) with cell dimensions a = 26.3 A, b = 52.0 A and c = 67.1 A, incorporating two B-DNA duplexes and four nogalamycin molecules in the asymmetric unit. The final refined structure included 97 water molecules, one spermine molecule, two acetate ions and one sodium ion, yielding an overall R factor of 19.2% (calculated using all 12,358 reflections in the resolution range 10.7 to 1.6 A) and an Rtree of 23.7% (using 1229 test reflections). The d5'(TGTACA)2 sequence was designed to include the d5'(TpG) pyrimidine-purine base step that has been ascertained as a preferential intercalation site. The complexes in the asymmetric unit are globally similar; one nogalamycin molecule intercalates between each d5'(TpG) step in each duplex. The DNA of each complex exists as a distorted B-DNA duplex displaying some Z-DNA character in the form of C3' endo sugars at some residues. Structural comparisons between the d5'(TGTACA)2-nogalamycin2 complex and the complexes of this drug with the sequences d5'(TGATCA)2 and d5'(5MeCGT(pS)A5MeCG)2 highlight differences in binding interactions between nogalamycin and these various triplet DNA binding sites, with regards to the stability of drug intercalation, which in turn is correlated to effective levels of cytotoxicity towards tumour cells. The number of both direct and water-mediated hydrogen bonds and van der Waal's interactions between substituents of nogalamycin and the d5'(TGTACA)2 and d5'(5MeCGT(pS)A5MeCG)2 sequences are significantly greater than those made with the d5'(TGATCA)2 sequence, suggesting that the central d5'(TpA) in the former confers additional stability to the complex once the drug has bound.     

Acceptance Testing?The Critical Problem in Software Acquisition

Contracting for computer software is a novel problem, with complex technical and legal issues. Acceptance testing is. the legal tool used to define satisfactory performance. However, both legal and technical concepts must be substantially improved to allow the contracting process to carry out the intentions of the parties.     

Comparison of tunica albuginea substitutes for the treatment of Peyronie's disease

PURPOSE: Peyronie's disease is a connective tissue disorder resulting in fibrotic plaque formation on the tunica albuginea of the penis. One approach to repair consists of plaque excision and patching with one of many potential patch materials. Because the optimal patch material for covering the resultant defect has not been determined, this study compares histological and cavernosometric changes in the penis as a result of the placement of three different types of patch grafts used in surgery for Peyronie's disease. MATERIALS AND METHODS: Eleven mongrel dogs were divided into three groups, each receiving a different patch material (superficial dorsal penile vein, silicone fabric, and dermabraded preputial flap). Each dog had dynamic infusion cavernosometry (DIC) performed prior to placement of the patch over a 6 x 3 mm. defect surgically created in the tunica albuginea. Three months later, DIC was repeated prior to sacrifice. Histology of the penis was examined using Masson's trichrome, and hematoxylin and eosin stains. RESULTS: The only difference among the cavernosometric parameters (preop versus postop) was a higher initial pressure in the dermabraded preputial flap group postoperatively. The dogs undergoing vein patch had moderate fibrosis with apparent reformation of the tunica albuginea over the patch site. The normal venous architecture of the graft was no longer recognizable. Those dogs receiving a silicone patch had moderate fibrosis with a fibrous sheath of compressed histiocytes and fibroblasts enveloping the graft site. Finally, the dermabraded preputial flap patch group had mild-moderate fibrosis with focal loss of the cavernosal space underlying the flap. CONCLUSIONS: We feel that continued use of the vein patch for repair of Peyronie's disease is warranted.     

The generation of hydrophilic polypeptide-siloxane conjugates via n-carboxyanhydride polymerisation

A novel methodology to create covalently linked polypeptide-siloxane hybrid materials by controlled n-carboxyanhydride ring opening polymerisation is disclosed. Poly-l-glutamic acid and poly-l-lysine conjugated products were formed that possessed excellent surface wettability. In addition, the poly-l-lysine-siloxane hybrids formed demonstrated bactericidal attributes against gram-positive Staphylococcus aureus and gram-negative Escherichia coli. It is anticipated that these materials may be of significance for the generation of hydrophilic siloxane-containing polymers that are commonly employed in contemporary medical devices.     

Ligand-induced conformational change in penicillin acylase

Wild-type and constitutively active mutants of human MAP kinase kinase-1 (MKK1) were analyzed by deuterium exchange mass spectrometry using a protocol that minimized loss of deuterium during analysis due to back exchange. The observed peptides accounted for 335 out of 393 residues. Not counting overlap peptides, three peptides showed decreased exchange in constitutively active compared to wild-type MKK1 and nine showed increased exchange. Backbone amides in which exchange rates decreased upon kinase activation were observed near the regulatory phosphorylation sites Ser218 and Ser222 and the adjacent beta9 strand. These decreases are consistent with electrostriction or reduced solvent access due to domain closure or formation of new hydrogen or salt bonds around the catalytic cleft and within the activation lip. Increased exchange upon activation was observed within six peptides derived from helix C and the five-stranded beta sheet from the N-proximal lobe of the conserved kinase domain and in one peptide located at the interface between the N- and C-proximal lobes. Two amides that underwent increased exchange were specifically localized between residues 68 and 69 in beta1 and 140 and 142 in beta5. These residues probably form contacts with each other on opposite sites of the beta sheet as well as with helix C. These increases appeared to represent localized fluctuations, rather than rigid body rearrangements, suggesting that MKK1 activation requires enhanced flexibility within the N-proximal lobe, perhaps to accommodate ATP binding, phosphotransfer, or ADP release.     

Nine critical elements of promising violence prevention programs

To identify approaches to school-based violence prevention that are most promising and those that may not be effective, a review of the literature was conducted. In addition, telephone interviews were conducted with 15 experts on topics related to school-based violence prevention. Nine critical ingredients of promising approaches to violence prevention were identified. Specifically, the approaches are comprehensive and multifaceted; begin in the primary grades and are reinforced across grade level; are developmentally tailored: and cover appropriate content area. Appropriate content areas include information; anger management; social perspective taking; decision making and social problem solving; peer negotiation and conflict management; social resistance skills; active listening and effective communication; and material on prejudice, sexism, racism and male-female relationship. In addition, promising programs use interactive teaching techniques, are culturally sensitive, and provide teacher training. They promote a positive school climate and foster norms against violence. Six violence prevention activities that appear not to be effective are also discussed. The authors conclude with a discussion of the need for more rigorous evaluation of violence prevention programs.     

Multivariate data modelling by metric approximants

Shepard developed a method for the interpolation of arbitrarily spaced discrete data points of two variables. We extend this scheme to approximate, by a smooth function, discrete sets of multivariate data points. No regularity is assumed for the data distribution, and we allow the dependent variable to contain error. The method presented here can be applied to the statistical analysis of experimental data as well as to the compression of data in computer graphics and computer aided design.     

Novel azobenzothiazole dyes from 2-nitrosobenzothiazoles

Novel azobenzothiazole dyes obtained by condensation of 2-nitrosobenzothiazoles with several substituted anilines were synthesized and characterized. The influence of solvent polarity on absorption spectra was examined, as was the relationship between dye structures and absorption in the UV–visible region. Azobenzothiazole dyes possessing an anilino unit which possessed an o-electron donating group, displayed unique absorption properties as revealed by a second, long wavelength absorption band.