Lagoutte¹ S, M Divo de Sesar², F V ilella³

Phyton-International Journal of Experimental Botany, Vol.78, pp. 31-36, 2009, DOI:10.32604/phyton.2009.78.031

Abstract Annual floral plant crops are produced in cells or pots of various sizes. Varying container size alters the volume which plant roots can explore, which in turn affect plant growth. This work assesed the effect of the initial container size on growth of Petunia x híbrida cv Dream Mix, supplemented with cytokinins after potting. Seedlings obtained in trays of 90 or 288 cells, were transplanted to 1l pots. They were then supplemented with 6-bencyladenine (BA). The assay consisted of 4 treatments: two container sizes by two BA conditions (with and without). Cell size conditioned growth above… More >

Ochoa-Fuentes YM¹, E Cerna², J Landeros², O Vazquez¹, V Olalde³, A Flores²

Phyton-International Journal of Experimental Botany, Vol.78, pp. 25-30, 2009, DOI:10.32604/phyton.2009.78.025

Abstract Forty two Mexican isolates of Phytophthora cinnamomi Rands were examined for genetic diversity by the random amplified polymorphic DNA assay. The amount of genetic variation was evaluated by polymerase chain reaction amplification with a set of twenty one random 10-mer primers. All amplifications revealed scorable polymorphisms among the isolates, and a total of 23 band positions were scored for the 21 primers tested. Genetic distances among the isolates were calculated, and cluster analysis was used to generate a dendogram which showed relationships between them. These results suggest that the geographic groups were strong. More >

Peláez¹ DV, RM Bóo², MD Mayor³, OR Elia⁴, SA Martínez⁵

Phyton-International Journal of Experimental Botany, Vol.78, pp. 17-24, 2009, DOI:10.32604/phyton.2009.78.017

Abstract Plant growth in semiarid rangelands may be affected by time grazing is excluded during the post-fire regeneration period. The objective of this field work was to study the effect of post-fire defoliation at different phenological stages [vegetative (early-season defoliation) and internode elongation (late-season defoliation)] on growth of Piptochaetium napostaense and Poa ligularis, two very important perennial native grasses in the temperate semi-arid region of central Argentina (Caldenal). In general, the post-fire defoliation treatments did not affect the number of green leaves on tillers of P. napostaense. Early-season post-fire defoliation generally reduced the number of green leaves on tillers… More >

Sánchez E¹, G Ávila-Quezada¹, AA Gardea¹, E Muñoz¹, JM Ruiz², L Romero²

Phyton-International Journal of Experimental Botany, Vol.78, pp. 11-16, 2009, DOI:10.32604/phyton.2009.78.011

Abstract The objective of this work was to determine the effect of different P doses on nitrogen assimilation in roots and leaves of green beans plants (Phaseolus vulgaris L. cv. Strike). Phosphorus was applied in the nutrient solution as H₃PO₄, at the nutrient doses of: P1 = 0.40 mM; P2 = 0.80 mM; P3 = 1.60 mM; P4 = 3.20 mM; P5 = 4.80 mM, and P6 = 6.40 mM P. Our results indicate that both P toxicity and deficiency gave similar responses to N assimilation. Phosphorus and NO3 - interacted on the absorption and translocation processes affecting More >

Chan RL

Phyton-International Journal of Experimental Botany, Vol.78, pp. 5-10, 2009, DOI:10.32604/phyton.2009.78.005

Abstract Transcription factors (TFs) are proteins able to specifically recognize DNA sequences in the regulatory regions of their target genes. They bind these specific sequences, an event that leads to the activation or repression of whole signal transduction pathways. In plants about 1500 TFs were informatically identified; identification was mainly based in the presence of DNA-binding domains in the translated sequences. They were classified in families and subfamilies according to several features, including the conservation of the DNA binding domain, the genes structures and the functions they exert. Among transcription factors, several seem to be potential… More >

Ugo Galvanetto, Paul Robinson, Agostino Cerioni, Carlos Lopez Armas

Structural Durability & Health Monitoring, Vol.5, No.2, pp. 161-190, 2009, DOI:10.3970/sdhm.2009.005.161

Abstract This paper presents a simple mathematical model to investigate various formulations of interface elements which are used to simulate fatigue driven delamination in composite materials. To illustrate the effectiveness of the model it is used to evaluate the performance of several different static constitutive laws and damage definitions coupled with a particular fatigue degradation strategy. It is shown that the model can be used to readily assess the robustness and reliability of the different formulations by examining hundreds of thousands of sets of parameter values in a rational and efficient manner. More >

M. Lavella¹, T. Berruti¹

Structural Durability & Health Monitoring, Vol.5, No.4, pp. 337-350, 2009, DOI:10.3970/sdhm.2009.005.337

Abstract Results of residual stress measurements on Inconel 718 turbine components after machining are here presented. The work is focused on the experimental detection of the residual stress state produced after turning (orthogonal cutting and standard) and milling. The aim of the experimental activity was to supply an experimental data base of proved reliability for milling and turning model validation. This activity was performed inside the EU STREP project VERDI. The residual stresses were detected by means of X-ray diffraction technique. The experimental plan of measurements was performed on components worked with different working parameters (cutting More >

Smitha Gopinath¹, J. Rajasankar^1,2, Nagesh R. Iyer¹, T. S. Krishnamoorthy¹, B.H.Bharatkumar¹, N. Lakshmanan¹

Structural Durability & Health Monitoring, Vol.5, No.4, pp. 311-336, 2009, DOI:10.3970/sdhm.2009.005.311

Abstract In this paper, a two-phase strain-based constitutive model is proposed for concrete under tension. First phase deals with modelling uncracked concrete while the behaviour of concrete in cracked condition is modelled in second phase with appropriate theoretical support. A bilinear tension softening curve of concrete defined in crack width-stress space is taken as the basis to propose the model. Smeared representation of reinforcement and cracks along with multi-layered geometry definition of reinforced concrete (RC) structures is used to implement the model. Through this, it is shown that change in the orientation of tensile cracks with… More >

Ramana M. Pidaparti¹, Ashwin Belle², Ju Wang³

Structural Durability & Health Monitoring, Vol.5, No.4, pp. 295-310, 2009, DOI:10.3970/sdhm.2009.005.295

Abstract This paper presents the development of a portable integrated wireless sensor module with video camera and ultrasound capabilities to monitor and investigate corrosion damage "in" structures. There are many studies in the literature on structural health monitoring with various sensors systems. However, very few of them utilize low power devices with reliable wireless communication capability to support data-intensive sensing which is a critical issue for practical applications. In this study, we developed a wireless sensor module with video camera capabilities and integrated it with a damage analysis module to investigate the damage of a structure. More >

I.S. Yoon¹, E.A.B. Koenders²

Structural Durability & Health Monitoring, Vol.5, No.4, pp. 275-294, 2009, DOI:10.3970/sdhm.2009.005.275

Abstract The critical chloride content for corrosion initiation is a crucial parameter in determining the durability and integrity of reinforced concrete structures, however, the value is still ambiguous. Most studies reporting the critical threshold of the chloride content have involved experimental measurements of the average amount of the total chloride content at an arbitrary time. Although carbonation can significantly impact on critical threshold chloride content, the majority of the researches have not dealt with this issue in combination with carbonation of concrete. Furthermore, many studies have tried to define the critical chloride content within the scope… More >