Evaluation of sesamum gum as an excipient in matrix tablets

In developing countries modern medicines are often beyond the affordability of the majority of the population. This is due to the reliance on expensive imported raw materials despite the abundance of natural resources which could provide an equivalent or even an improved function. The aim of this study was to investigate the potential of sesamum gum (SG) extracted from the leaves of Sesamum radiatum (readily cultivated in sub-Saharan Africa) as a matrix former. Directly compressed matrix tablets were prepared from the extract and compared with similar matrices of HPMC (K4M) using theophylline as a model water soluble drug. The compaction, swelling, erosion and drug release from the matrices were studied in deionized water, 0.1 N HCl (pH 1.2) and phosphate buffer (pH 6.8) using USP apparatus II. The data from the swelling, erosion and drug release studies were also fitted into the respective mathematical models. Results showed that the matrices underwent a combination of swelling and erosion, with the swelling action being controlled by the rate of hydration in the medium. SG also controlled the release of theophylline similar to the HPMC and therefore may have use as an alternative excipient in regions where Sesamum radiatum can be easily cultivated

Traditions west of the Euphrates at the beginning of the Late Chalcolithic. Characteristics, definitions, and supra-regional correlations

This paper discusses the relationships between the Turkish Upper Euphrates and regions located to the southwest, near the Syro-Turkish border, during the early stages of the Late Chalcolithic period. This period is best represented in these regions by the sites of Arslantepe and Oylum Höyük. While a detailed presentation of the early Late Chalcolithic occupation levels of Arslantepe and Oylum Höyük is provided elsewhere in this volume, their pottery assemblages are here compared in order to identify common characteristics, together with interregional connections with contemporary sites located to the north, the west and the east.This paper discusses the relationships between the Turkish Upper Euphrates and regions located to the southwest, near the Syro-Turkish border, during the early stages of the Late Chalcolithic period. This period is best represented in these regions by the sites of Arslantepe and Oylum Höyük. While a detailed presentation of the early Late Chalcolithic occupation levels of Arslantepe and Oylum Höyük is provided elsewhere in this volume, their pottery assemblages are here compared in order to identify common characteristics, together with interregional connections with contemporary sites located to the north, the west and the east

Archaeometallurgical Investigations in Nakhchivan, Azerbaijan: What Does the Evidence from Late Chalcolithic Ovçular Tepesi Tell Us about the Beginning of Extractive Metallurgy?

International audienceThe Late Chalcolithic (4400–3950 b.c.) occupation levels from Ovçular Tepesi have yielded a significant assemblage of copper objects and remains of copper production. Together with ore finds, two fragments of nozzle, crucible remains, and a number of small metal artifacts, this assemblage includes the unexpected discovery of three copper axes in an infant burial jar. These axes are the earliest examples of large copper tools known to date in southwestern Asia, whether it is in the Caucasus, Iran, or the Anatolian highlands. More importantly, the fact that these objects were locally produced suggests that significant metallurgical activities were being carried out at Ovçular as early as the second half of the 5th millennium b.c. After presenting the evidence from Ovçular Tepesi, this paper will proceed to a reassessment of the available archaeological and geochemical data concerning the emergence of extractive metallurgy in the southern Caucasus. © 2017, © Trustees of Boston University 2017