Effectiveness of different pre-treatments in recovering pre-burial isotopic ratios of charred plants

Rationale: Isotopic analysis of archaeological charred plant remains offers useful archaeological information. However, adequate sample pre-treatment protocols may be necessary to provide a contamination-free isotopic signal while limiting sample loss and achieving a high throughput. Under these constraints research was undertaken to compare the performance of different pre-treatment protocols. Methods: Charred archaeological plant material was selected for isotopic analysis (δ13C and δ15N values) by Isotope Ratio Mass Spectrometry (IRMS) from a variety of plant species, time periods, and soil conditions. Preservation conditions and the effectiveness of cleaning protocols were assessed through Fourier transform infrared spectroscopy (FTIR) and X-Ray fluorescence (XRF) spectrometry. An acid-base-acid protocol, successfully employed in radiocarbon dating, was used to define a contamination-free isotopic reference. Acid-base-acid isotopic measurements were compared with those obtained from untreated material and an acid-only protocol. Results: The isotopic signals of untreated material and an acid-only protocol typically did not differ more than 1‰ from those of the acid-base-acid reference. There were no significant isotopic offsets between acid-base-acid and acid-only or untreated samples. Samples losses in an acid-base-acid protocol were on average 50±17% (maximum = 98.4%). Elemental XRF measurements showed promising results in the detection of more contaminated samples albeit with a high rate of false positives. Conclusions: For the large range of preservation conditions described in the study, untreated charred plant samples, water cleaned of sediments, provide reliable stable isotope ratios of carbon and nitrogen. The use of pre-treatments may be necessary under different preservation conditions or more conservative measurement uncertainties should be reported

Marketing Practices and Distribution System of Rice in Punjab, India

The study focuses on the marketing practices, market structures, and firms’ motives for vertical co-ordination of the paddyrice distribution system during the post green revolution period in the Punjab state of India. The study is based upon secondary data taken from several published sources and intensive interviews with the market agents in the entire distribution chain from growers to the retailers. Study highlighted the emergence of public sector as a giant player in the paddy (non-basmati) wholesale markets, unscrupulous practices for paddy/rice supplies, wide disparities in the issue prices for the below and above poverty line families, reduced off take from the public distribution system, launching of several schemes to off load excessive stocks, and improve market efficiency. Open market segment of the industry is highly fragmentedwherein a large majority of themarket agents have confined at the levels they can be best managed, vertical co-ordination plays a pivotal role to cope up with market imperfections and supply agents constitute a strategic link for rice sales. However, private milling gains momen-tum particularly during the downward phase of the industry due to increased profitabilit

Financially sustainable investments in developing countries water sectors: what conditions could promote private sector involvement?

Water, Public–private partnership, Investments,