A Comparison of Genetic Segregation in Traditional and Microspore-Derived Populations of Brassica juncea L. Czern and Coss.

An isolated microspore culture procedure was used to produce doubled haploid lines of Brassica juncea from F¹ plants of reciprocal crosses between the cultivar‘RLM514’and a canola quality breeding line. The inheritance of two qualitative markers, seed color and leaf hairiness, was compared using traditional and microspore-derived populations from these crosses. Chi-square tests indicated that each trait is controlled by different sets of duplicate pairs of genes. Brown seeds or hairy leaves can result from the presence of either of two dominant alleles, whereas yellow seed or glabrous leaves are produced when alleles at both loci are recessive. The segregation of genes controlling seed color and leaf hairs in doubled haploid progeny did not differ significantly from that expected under random assortment, indicating that doubled haploids can be used in this species for genetic studies, and probably cultivar development as well.     

Yarn setting and hairiness reduction with a steam jet during winding

This paper examines the use of pressurized steam for wrapping and setting the yarn hairs concurrently via a new steam-jet process during winding. Yarn torque can also be stabilized as an added advantage. The results obtained with two batches of pure wool yarns suggest that there is potential to achieve yarn hairiness reduction of up to 60 % with minimum deterioration in hairiness even after subsequent rewinding.     

Air pollution removal through deposition on urban vegetation: The importance of vegetation characteristics

Urban vegetation has the potential to improve air quality as it promotes pollutant deposition and retention. Urban air quality models often include the effect vegetation have on pollution dispersion, however, processes involved in pollution removal by vegetation are often excluded or simplified and does not consider different vegetation characteristics. In this systematic review, we analyze the influence of the large interspecies variation in vegetation characteristics to identify the key factors affecting the removal of the major urban pollutants, particulate matter (PM) and nitrogen dioxide (NO₂) from the air through vegetation deposition. The aim is to identify key processes needed to represent vegetation characteristics in urban air quality modelling assessments.We show that PM is mainly deposited to the leaf surface, and thus representation of characteristics affecting the aerodynamics from canopy down to leaf surface are important, such as branch/shoot complexity and leaf size, leaf surface roughness and hairiness. In addition, characteristics affecting PM retention capacity, resuspension and wash-off, include leaf surface roughness, hairiness and wax content. NO₂ is mainly deposited through stomatal uptake, and thus stomatal conductance and its responses to environmental conditions are key factors. These include response to solar radiation, vapour pressure deficit and soil moisture.Representation of these vegetation characteristics in urban air quality models could greatly improve our ability to optimize the type and species of urban vegetation from an air quality perspective.     

An experimental investigation of yarn tension in simulated ring spinning

Yarn tension is a key factor that affects the efficiency of a ring spinning system. In this paper, a specially constructed rig, which can rotate a yarn at a high speed without inserting any real twist into the yarn, was used to simulate a ring spinning process. Yarn tension was measured at the guide-eye during the simulated spinning of different yarns at various balloon heights and with varying yarn length in the balloon. The effect of balloon shape, yarn hairiness and thickness, and yarn rotating speed, on the measured yarn tension, was examined. The results indicate that the collapse of balloon shape from single loop to double loop, or from double loop to triple etc, lead to sudden reduction in yarn tension. Under otherwise identical conditions, a longer length of yarn in the balloon gives a lower yarn tension at the guide-eye. In addition, thicker yarns and/or more hairy yarns generate a higher tension in the yarn, due to the increased air drag acting on the thicker or more hairy yarns.