14 research outputs found
Tackling the salinity-pollution nexus in coastal aquifers from arid regions using nitrate and boron isotopes
Salinization and nitrate pollution are generally ascertained as the main issues affecting coastal aquifers worldwide. In arid zones, where agricultural activities also result in soil salinization, both phenomena tend to co-exist and synergically contribute to alter groundwater quality, with severe negative impacts on human populations and natural ecosystems’ wellbeing. It becomes therefore necessary to understand if and to what extent integrated hydrogeochemical tools can help in distinguishing among possible different salinization and nitrate contamination origins, in order to provide adequate science-based support to local development and environmental protection. The alluvial plain of Bou-Areg (North Morocco) extends over about 190 km2 and is separated from the Mediterranean Sea by the coastal Lagoon of Nador. Its surface is covered for more than 60% by agricultural activities, although the region has been recently concerned by urban population increase and tourism expansion. All these activities mainly rely on groundwater exploitation and at the same time are the main causes of both aquifer and lagoon water quality degradation. For this reason, it was chosen as a case study representative of the typical situation of coastal aquifers in arid zones worldwide, where a clear identification of salinization and pollution sources is fundamental for the implementation of locally oriented remedies and long-term management strategies. Results of a hydrogeochemical investigation performed between 2009 and 2011 show that the Bou-Areg aquifer presents high salinity (often exceeding 100 mg/L in TDS) due to both natural and anthropogenic processes. The area is also impacted by nitrate contamination, with concentrations generally exceeding the WHO statutory limits for drinking water (50 mg/L) and reaching up to about 300 mg/L, in both the rural and urban/peri-urban areas. The isotopic composition of dissolved nitrates (δ15NNO3 and δ18ONO) was used to constrain pollution drivers. The results indicate two main origins for human-induced pollution: (i) manure and septic effluents, especially in urban areas, and (ii) synthetic fertilizers in agricultural areas. In the latter, δ15N-enriched values highlight a mixture of those sources, possibly related to unbalanced fertilization and agricultural return flow. Boron isotopes (δ11B) were hence studied to further distinguish the nitrate origin in the presence of multiple sources and mixing processes. The results indicate that in the study area, the high geochemical background for B and Cl, associated to the complex water-rock interaction processes, limit the application of the coupled δ11B and δ15N isotopic systematics to the detection of sources of groundwater pollution. In fact, despite the exceedingly high nitrate contents, the depleted δ11B values that characterize synthetic fertilizers and sewage leakages could not be detected. Therefore, even if in saline groundwater the anthropogenic contribution has a negligible effect in terms of salinity input, with both sewage and irrigation water not very charged, the associated nitrate content fuels up water-rock interaction processes, eventually leading to a mineralization increase
Decomposing productivity patterns in a conditional convergence framework
Conditional convergence, Shift-share decomposition, SUR estimation, C13, C21, C23, O18, O47,
Garlic Oil and Vitamin E Prevent the Adverse Effects of Lead Acetate and Ethanol Separately as well as in Combination in the Drinking Water of Rats
Daily feeding of drinking water containing lead acetate (160 mg/l) or 10% alcohol by volume or a combination of both to rats for a month produced certain deleterious effects through oxidative stress. Both heavy metal lead and alcohol are capable of doing such damages. The deleterious alterations observed were in the parameters of blood, serum and tissues, viz; Hb, Pb, proteins, lipids, lipid per oxidation, Vitamins C and E levels and enzyme activities of AST, ALT, and catalase. Simultaneous feeding of either of the two antioxidants garlic oil (GO) and vitamin E at equal doses of 100 mg/kg/day, to the rats counteracted the deleterious effects of the above two chemicals significantly. The maximum damage was brought about by feeding of drinking water containing both lead acetate and alcohol. The protective effects of GO and Vitamin E were not significantly different. The mechanism of actions of the Vitamin E and GO is probably due to their efficiency as detoxifying agents and antioxidants, to scavenging free radicals as well as an independent action of GO on the removal of lead salt as lead sulfide
INTRODUCTIONOffshoring administrative and technical work: New fields for understanding the global enterprise
In this paper, we introduce the Journal of International Business Studies Special Issue on Offshoring Administrative and Technical Services (ATS). In doing so, we have attempted to locate the topic within the international business research tradition, as well as suggest challenges and opportunities that the phenomenon offers to theoretical and empirical research in the field. We examine the interplay of costs, knowledge, and innovation in the evolution of ATS offshoring from modest beginnings to its current stature as an accepted business practice. We suggest that understanding the continuing evolution of ATS offshoring requires researchers to take into account not only the business imperative of cost-saving, but also a more complex set of underlying factors and potential outcomes. We argue that the rapid growth of ATS offshoring has brought about an accumulation of resources, including financial flows, knowledge, infrastructure and human capital to create new platforms for knowledge creation and innovation. Low costs may characterize the initial conditions for offshoring, but they also provide the basis for up-market moves as firms increasingly pursue innovation-based strategies. We introduce the papers in the Special Issue as integral elements in our discussion, contributing new ideas that stimulated our thinking and, hopefully, will do the same for others seeking to understand this emerging area of globalization and international managerial practice. Journal of International Business Studies (2009) 40, 887–900. doi:10.1057/jibs.2009.22