Longitudinal spillover effects of conflict resolution styles between adolescent-parent relationships and adolescent friendships.

This study longitudinally investigated spillover effects of conflict resolution styles in adolescent-parent relationships and adolescent friendships. Questionnaires about conflict resolution styles with parents and best friends were completed by adolescents from two age cohorts: 559 early adolescents (mean age 13.4) and 327 middle adolescents (mean age 17.7). Path analyses on two waves, with a three-year interval, indicated that in the early-to-middle adolescent group positive problem solving and conflict engagement spilled over from adolescent-parent relationships to adolescent friendships and not from adolescent friendships to adolescent-parent relationships. In the middle-to-late adolescent group, we found bidirectional spillover effects for these two conflict resolution styles. For withdrawal, we found bidirectional spillover effects in both cohorts. This study showed that both parents and friends set the stage for exercising and learning conflict resolution styles and thereby shape adolescents' future conflict behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Functional and molecular properties of calcium precipitated soy glycinin and the effect of glycation with κ-carrageenan

This study describes an extraction process for the preparation of highly purified calcium precipitated glycinin (11S). Initial extraction of soy proteins using isoelectric precipitation at pH 6.8 followed by cryo-precipitation yielded 4.2% product (11S) recovery with 98% protein purity for the control extracted with NaOH. Addition of calcium chloride (CaCl₂) doubled the extraction yield (9%) compared to the control and when two other salts were used (i.e., sodium (Na₂SO₄) and ammonium (NH₄)₂SO₄ sulfate, average yields of 4.4% and 5.17%, respectively). Thermal and molecular stability under varying conditions (pH, salts, SDS as a protein structure perturbing agent), and effect of glycation on functional and structural properties were investigated. Size exclusion chromatography and electrophoresis confirmed the predominance of a major band with MW of ～342 kDa with 98.4% purity. Differential scanning calorimetry (DSC) yielded one endothermic transition peak at 95.5 °C. Denaturation temperatures were >100 °C for all salt concentrations studied. The pH had a dominant influence on the structural properties of glycinin. In the presence of NaCl and CaCl₂ (0.2–1 M), the protein structure showed very little denaturation and no aggregation bands were observed even on heating to 95 °C. Lower SDS concentrations (0.5–1%) resulted in denaturation and aggregation, while at 2% SDS only denaturation was observed. Glycation did not alter the conformational structure of protein. Improvements in surface properties were observed with moderate degree of glycation (6–24 h).     

Improvement of the manufacturing process of abrasive stones for honing

In the present work, the mixing process of different components of abrasive stones of cubic boron nitride used for rough honing was studied. Stones are made by the sintering process of abrasive grains, a metallic bond, and a humectant that favors covering of each abrasive grain by the bond. Incorrect mixing of abrasive grains with the bond and humectant can result in stones with nonuniform abrasive grain distribution. As the abrasive stone wears out, grain distribution will vary and modify efficiency of the honing operation. Tin is the metal having the lowest melting point among metals in the bond. By means of a scanning electron microscope and energy-dispersive X-ray microanalysis, tin segregation was discarded, which could have led to abrasive grain segregation. Later, mixing tests of the different components of the stones were performed at different mixing times. Both homogeneity degree of the abrasive content of different samples in a mix and covering degree of abrasive grains by bond were determined through two new parameters introduced in the present study. It was noted that use of a chain to accelerate the mixing process excessively reduces covering degree of abrasive grains even at initial mixing times. The highest quantity of humectant is recommended in order to get better covering degree. Mixing time should be high enough to assure homogeneity degree of the mix but low enough to avoid excessive reduction of covering degree.     

Applicability assessment of a real-time PCR assay for the specific detection of bovine,ovine and caprine material in feedstuffs

A TaqMan real-time polymerase chain reaction (PCR) method was developed for specific detection of bovine, ovine and caprine processed animal protein (PAP) in industrial feedstuffs. The method uses species-specific primers and probes targeting short mitochondrial D-loop sequences, and a positive amplification control based on 18S rRNA gene. The applicability of the real-time PCR protocol was assessed through analysis of 126 industrial feed samples that were manufactured to reproduce rendering processes of commercial feeds destined for farmed animals. The assay successfully classified samples as positive or negative according to the ruminant composition, enabling qualitative detection of banned material in feeds at levels as low as 0.1%. Although the method provides quantitative potential, results suggest that the real quantitative capability of the assay is limited by the existing variability in terms of composition and processing treatments of the feeds, which affect the amount and quality of amplifiable DNA.     

Effect of Aging on the Fracture Behavior of Lean Duplex Stainless Steels

The influence of aging in the range of 550 °C to 850 °C for 5 to 120 minutes on the impact fracture behavior of 2101 and 2304 lean duplex stainless steels (DSS) was investigated in the present study. The 2304 steel displayed ductile behavior irrespective of aging conditions. In contrast, the 2101 steel displayed a ductile behavior only in the case of aging for 5 minutes at 550 °C and 650 °C, whereas in all other cases, it fractured in a brittle manner. The brittle fracture behavior of the 2101 steel has been attributed to the precipitation of small black particles at the α/α and α/γ grain boundaries (nitrides), which form paths for easy crack propagation. In the 2304 steel, such particles precipitated at 750 °C and 850 °C, but they were located inside the austenitic grains because of the formation of secondary austenite. They therefore did not embrittle the steel. The larger Ni content of the 2304 steel favored the formation of the secondary austenite that is absent in the 2101 steel.     

Identifying Shared Environmental Contributions to Early Substance Use: The Respective Roles of Peers and Parents.

Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c2 = .51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Increased globotriaosylceramide in familial dysautonomia

Familial Dysautonomia (FD) is an autosomal recessive disease of unknown etiology, occurring primarily in Ashkenazi Jews. Patients are neurologically impaired, with deficits primarily in autonomic and sensory functions. The biochemical and genetic defects have remained elusive, precluding carrier detection and prenatal diagnosis. High-performance liquid chromatography data indicated up to a threefold increase in the neutral glycosphingolipid globotriaosylceramide in Dysautonomic fibroblasts and lymphoblasts. Total ganglioside values, measured by colorimetric, fluorometric or specific sodium borohydride incorporation, were decreased. Affected fibroblasts exhibited a range of pleomorphic phenotypes, such that the usual swirl-like confluent growth pattern of normal fibroblasts was distorted to varying degrees, suggesting abnormalities in the FD plasma membrane, possibly affecting cell-cell contacts. The glycosphingolipid increase could not be accounted for on the basis of markedly decreased α-galactosidase activity, as in Fabry's disease, where patients also display decreased autonomic function.     

Parenting Behaviors and the Occurrence and Co-Occurrence of Depressive Symptoms and Conduct Problems Among African American Children.

The occurrence and co-occurrence of depressive symptoms and conduct problems were examined in the context of parenting behaviors in a community-based sample of 897 African American children and their primary caregivers using a multi-informant, longitudinal design. Parenting behaviors and clinical symptoms were assessed in 2 waves, when the children averaged 10.5 and 12.3 years of age. Parenting behaviors differed significantly according to a child's symptomatology; (a) that is, when a child exhibited no depressive or conduct problems, (b) depressive problems only, (c) conduct problems only, or (d) co-occurring depressive and conduct problems. When parenting behaviors were examined according to changes in children's symptom levels, children whose symptoms increased over time reported increases in hostility and harsh-inconsistent parenting and decreases in warmth and nurturant-involved parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)