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After 27 years of service, bridge LIC-310, a deteriorated adjacent prestress concrete box beam bridge, was removed and several of its girders were forensically and destructively tested to determine their remaining structural capacity. Based on this information, analytical models were developed to investigate the influence of the deterioration on the individual and collective performance of the girders. Finally, the results of these models were used to rate the bridge according to two different methodologies; Load Factor Rating (LFR) and Load and Resistance Factor Rating (LRFR). For each of these approaches, the bridge was analyzed as a simply and continuous supported structured. For simply supported conditions, the study concluded that based on the experimental capacities and adopting the LRFR methodology, the bridge should have been posted to 21 tons. Moreover, it recommended replacing the pier diaphragms to take full advantage of the continuity system and to strength and repair the girders that exhibited a high deterioration stage.

Rooting performance of two rose species were compared. The effect of sucrose, nitrogen, IBA, presence of leaves and maturity of the cuttings on rooting were examined and the endogenous levels of IAA, GA and cytokinins and rooting co-factor activity were determined in their methanolic extracts. The determination for ABA did not yield results. R. multiflora one-node cuttings rooted better than R. bracteata ‘Mermaid’. Sucrose and IBA treatments improved rooting of R. multiflora while nitrogen inhibited it. Rooting of R. multiflora stem cuttings were influenced by the number of leaves present in the cuttings, maturity and IBA concentration. The presence of leaves improved rooting. Harder stems (8th-19th node) rooted better than very young ones (0-7th node) while 750 ppm IBA significantly induced better rooting than 1500 ppm IBA. Significant interactions were obtained between maturity x hormone concentration and number of leaves x hormone concentration. It appears that more mature stem cuttings will root better if IBA is present while the presence of leaves seems to replace the favourable effect of IBA. Cuttings of R. multiflora are probably characterized by high concentrations of GA and low levels of IAA and cytokinin but greater rooting co-factor activity. Apparently R. bracteata 'Mermaid' has high GA and cytokinin levels and low free IAA plus lack of rooting co-factor activity and presence of inhibitors.