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Cuscuta reflexa Roxb. belonging to family Cuscutaceae was explored for its pollen morphology and its pollen characters examined with light and scanning electron microscope were compared with six species belonging to family Convolvulaceae. Pollen samples were collected from Districts; Kotli, Bhimber and Mirpur, Azad Jammu & Kashmir, Pakistan. Flowers of Cuscuta reflexa Roxb., five species of Ipomoea including Ipomoea carnea Jacq., Ipomoea cairica (L.) Sweet, Ipomoea hederacia Jacq., Ipomoea pes-tigridi sL., Ipomoea eriocarpa R.Br., Ipomoea arachnosperma Welw. and Convolvulus arvensis L. were collected. Pollen shape of these selected species are generally prolate, subprolate, prolate-spheroidal, oblate spheroidal and perpolate. The apertures of the pollens of these taxa were found scabrate, scabrate-perforate, reticulate and echinate-reticulate. Among the examined taxa, C. reflexa Roxb. has smallest size of pollen (2-5×2.5-5pm) while the largest pollen (28.5-37.6 × 24.7-28.9pm) belongs to the Ipomoe acarnea. It has been founded that pollen of Cuscuta reflexa Roxb. is prolate in shape and was similar to I. carnea Jacq, I. pes-tigridis L, I. eriocarpa R.Br pollens. Hierarchical cluster analysis based on pollens observations grouped I. arachnosperma and Cuscuta refelexa together at maximum similarity 99.86 at a distance level of 0.003. It has been concluded from this study that Cuscuta refelexa pollen are exactly similar to Ipomea arachnosperma on the bases of pollen morphology and exine appearance. [ABSTRACT FROM AUTHOR]

This paper characterizes the sugarcane bagasse ash as a pozzolan and investigates its influence on the hardened properties of concrete. In Pakistan, the sugar industry recycles raw bagasse for power generation, and as a result, tonnes of bagasse ash are produced every year. For this study, the bagasse ash sample was obtained from one of the local sugar mills of Pakistan. The physical, chemical and mineralogical of bagasse ash were investigated by employing X-ray diffraction (XRD), X-ray fluorescence and laser particle size techniques, while the microstructure was studied through scanning electron microscope. In addition, the evaluation of hardened properties like compressive strength, tensile strength, flexural strength and thermal conductivity was also carried out. Here, the concrete mixtures were prepared by replacing the cement with bagasse ash in the ratio of 5 to 30% (by weight). The chemical, physical and mineral results reveal that this local bagasse ash has all pozzolanic properties. The evidence of amorphous and crystalline phases was found in the XRD pattern, along with silicon dioxide (SiO2) which was recorded more than 70% in the ash. It was observed that the workability for bagasse ash-blended concrete mixtures increases with ash content. Furthermore, the bagasse ash mixtures with 10% substitution were found optimal for achieving higher compressive, flexural and tensile strength, while the thermal conductivity showed a consistent drop with higher ash content percentage. [ABSTRACT FROM AUTHOR]