The effects of periodontal therapy on serum antibody levels to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis (part II)

Levels of IgG and IgM antibodies were estimated against Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were determined by enzyme linked immunosorbent assay (ELISA) in 17 patients with juvenile periodontitis, 15 with adult periodontitis and 24 healthy controls at the beginning of treatment and 3 to 8 months after periodontal therapy. After treatment, antibodies to A. actinomycetemcomitans and P.gingivalis had decreased in patients, but the levels were still significantly higher than in healthy controls. Whether or not an of antibody level against a specific bacteria changes after periodontal treatment is however, still debatable.     

Observed sibling interaction: links with the marital and the mother-child relationship

The study examines whether the link between the marital relationship and sibling interaction is direct or mediated by the mother-child relationship. Seventy-three same-sex siblings pairs aged 3 years 6 months to 8 years 6 months were observed during free play. Mothers completed questionnaires assessing marital functioning and their relationship with their 2 children. Results indicated that older siblings' negative behavior is linked with negative dimensions of the marital and the mother-child relationship, whereas younger siblings' negative behavior is linked with the mother-child and the differential mother-child relationship. Siblings; positive behavior, although linked with spacing, is not linked with positive dimensions of family interaction. Most important, the linkage between negative marital relations and older siblings; negative behavior was found to be mediated by maternal power assertion, thereby supporting the indirect model of negative family interaction.     

Fine grinding of thermoplastics by high speed friction grinding assisted by guar gum

High speed friction grinding has been used to grind plant and food substances in water but never been explored for grinding of thermoplastics like polylactic acid (PLA), low and high density polyethylene and polypropylene. Such grinding was investigated in this work and was made possible by using 0.5% guar gum solution instead of just water because increasing the viscosity of water reduced their settling and the speed of passing through the grinder. Tensile, flexural, and impact strengths of the plastics were studied and higher grinding efficiency of PLA could be explained by its low elongation-at-break compared to low density polyethylene, high density polyethylene, and polypropylene. The microplastics (2000–45 μm) were studied for mass and particle size distributions and by scanning electron microscopy, ¹³C CP/MAS NMR, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In addition, viscosity of guar gum and contact angles was measured. This new technology can produce finely ground microplastics (710–45 μm) for a variety of applications.     

Towards quality requirements via animated formal specifications

Assuring a high quality requirements specification document involves both an early validation process and an increased level of participation. An approach and its supporting environment which combines the benefits of a formal system specification and its subsequent execution via a rapid prototype is reported. The environment assists in the construction, clarification, validation and visualisation of a formal specification. An illustrative case study demonstrates the consequences of assertions about system properties at this early stage of software development. Our approach involves the pragmatic combination of technical benefits of formal systems engineering based techniques with the context‐sensitive notions of increased participation of both developer and user stakeholders to move us closer towards a quality requirements specification document.     

Determination of Myricetin in Medicinal Plants by High-Performance Liquid Chromatography

The concentrations of myricetin in medicinal plants such as Rosa canina L. (rosa hip), Terebinthina chica L. (terebinth), Urtica dioica L. (nettle), and Portuca oleracea L. (purslane) were determined by high-performance liquid chromatography-mass spectrometry (HPLC-MS). The aglycones of myricetin were extracted using methanol–ascorbic acid– hydrochloric acid, methanol–hydrochloric acid, and methanol, separated within 5 min, and individually quantitated in the positive ionization mode using optimized conditions for HPLC-MS. Methanol–ascorbic acid–hydrochloric acid was the optimum extraction solvent. The myricetin concentration in the plants were between 3 and 58 mg kg^?1, with a limit of quantification equal to 0.1 mg L^?1.     

Performance of teetered bed separator for non-coal applications

In the present investigation, the effect of the most important process variables, which are teeter water velocity (TW) and pressure set point (SP), on the classification and beneficiation performance of a laboratory-scale teetered bed separator (TBS) was evaluated and discussed. Pure silica sand, magnetite concentrate and their artificial mixture were used to observe the effect of mineral density. Classification test results revealed that separation cut size linearly increases with increasing TW and SP. From the beneficiation studies and the size-by-size chemical analysis of artificial mixture, it can be concluded that significant removal of silica is possible by employing TBS.