Gene duplications are prevalent in plants, and functional divergence subsequent to duplication may be linked with the occurrence of novel phenotypes in plant evolution. Here, we examine the functional divergence of Arabidopsis thaliana APETALA1 (AP1) and FRUITFULL (FUL), which arose via a duplication correlated with the origin of the core eudicots. Both AP1 and FUL play a role in floral meristem identity, but AP1 is required for the formation of sepals and petals whereas FUL is involved in cauline leaf and fruit development. AP1 and FUL are expressed in mutually exclusive domains but also differ in sequence, with unique conserved motifs in the C-terminal domains of the proteins that suggest functional differentiation. To determine whether the functional divergence of AP1 and FUL is due to changes in regulation or changes in coding sequence, we performed promoter swap experiments, in which FUL was expressed in the AP1 domain in the ap1 mutant and vice versa. Our results show that FUL can partially substitute for AP1, and AP1 can partially substitute for FUL; thus, the functional divergence between AP1 and FUL is due to changes in both regulation and coding sequence. We also mutated AP1 and FUL conserved motifs to determine if they are required for protein function and tested the ability of these mutated proteins to interact in yeast with known partners. We found that these motifs appear to play at best a minor role in protein function and dimerization capability, despite being strongly conserved. Our results suggest that the functional differentiation of these two paralogous key transcriptional regulators involves both differences in regulation and in sequence; however, sequence changes in the form of unique conserved motifs do not explain the differences observed.

ABSTRACT:The amount of ply twist required to bring the surface fibers of the strand parallel to ply yarn axis is half the single yarn twist and, is experimentally verified by viewing the multifilament yarns longitudinally under Scanning Electron Microscope. The effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of two-ply cotton yarn have been studied. As the single yarn twist increases the tensile strength of the ply yarns with different levels of ply to single yarn twist ratio increases and at 130 -140% of normal single yarn twist level, the ply yarns attain almost the same strength. Rate of improvement in tensile strength of cotton two-ply yarn with respect to single yarn twist is more than that with respect to ply twist. The effect of ply to single yarn and cable to ply yarn twist ratio on strength and elongation of ply and cable multifilament yarns have been studied. Tensile strength of ply and cable multifilament yarns do not vary with the change in ratio of ply to single yarn twist and cable to ply twist respectively, particularly when the resultant yarn is finer. The cosine of average filament inclination to the ply yarn axis and that to the cable yarn axis do not vary much with different levels of ply to single yarn twist ratio and cable to ply yarn twist ratio respectively.

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2D fabrics are used widely and to good effect as a reinforcement for many planer composites and simple curved structures, i.e. a cylindrical arc. There are, however, manufacturing difficulties in the formation of composite structures which are curved across two axes, i.e. a bowl shape. This can be addressed by manufacturing “3D” fabric preforms; however, this requires complex machinery and is slow and expensive. It is, therefore, desirable to form complex curved shapes from planer textile structures; this is either done by cutting a net shape from the textile and placing it on a mold or by using force to stretch the fabric to the mold. These methods, however, result in discontinuous reinforcement or poor distribution of phases, respectively. Wrinkling of the fabric during formation will increase the possibility of composite failure under loading because of the presence of rich fiber or resin areas. A new method was suggested to manufacture 3D shapes from 2D fabric through the application of cyclic loading on the 2D fabric under a continuous hot air till the final fabric prepreg bagging form is reached. The composite fabrication process was completed in two steps: imposing dynamic bagging of the chemically treated 2D Jute fabric with 16% sodium hydroxide in slack form to fit the die final shape prior to the infusing of the resin accompanied by pressing two halves of the mold. A proto-type setup was designed to study the two-step fabrication method for various shapes of 3D fabric reinforcement.

This paper is concerned with the optimization of a double-rove spinning process in the short staple spinning system, using Box and Hunter's technique of a central compound rotatable design. The influences of strand spacing, twist, and spindle speed on yarn tensile and regularity properties are discussed.Double-rove spinning is becoming more popular because of tremendous cost savings [5,9]. Although there is a considerable amount of work on the properties of double-rove yam produced on the short staple spinning system [ 3,4,8 ], the optimization of doublerove spinning parameters using a factorial analysis has not been so far reported in the literature. Our work concerns the optimization of the three most important double-rove spinning parameters: strand spacing, twist multiplier, and spindle speed. We have used the design developed by Box and Hunter [ 2 ] , which was used by Barella et al. [ I ] in optimizing the rotor spinning process. The yam quality is assessed in terms of its tensile and regularity properties. ExperimentalIn this paper, the zero spaced double-rove yam is considered as a control yam and the others are spaced double-rove (SDR) yarns. The experiments to produce SDR yams were planned according to the rotatable design of Box and Hunter [2] ] for three variables: strand at UNIV OF PITTSBURGH on June 19, 2015 trj.sagepub.com Downloaded from