Fishing and Farming at Lake Chad: Responses to Lake-level Fluctuations
摘要:
Lake Chad lies at the southern extreme of the Sahara Desert and is well known for large fluctuations in its surface area this century. Seasonal fluctuations, however, have received much less attention. This paper presents the results of two complimentary research efforts on the south‐west shore of the lake. These illustrate how important both inter and intra‐annual fluctuations in the level of the lake are, both in terms of their impact on the environment and in the response of the communities living on the lake shore. The paper compares a time series of the fluctuations in the level of Lake Chad as monitored by the TOPEX/POSEIDON satellite with findings from participatory research with the communities of the south‐west lake shore. It shows how the communities of the lake have responded to lake‐level fluctuations with their livelihood choices. These results are used to show that although vastly different in scope, a high degree of complimentarity exists between remotely‐sensed information and community‐based research and that they are of potentially great value to development initiatives on the shores of Lake Chad.
Scope of the formal [3+2] cycloaddition for the synthesis of substituted 3-arylindanes and related compounds
作者:Beatriz Lantaño、José Manuel Aguirre、Esteban Ariel Ugliarolo、María Laura Benegas、Graciela Yolanda Moltrasio
DOI:10.1016/j.tet.2008.02.034
日期:2008.4
We report the single step synthesis of several 3-arylindanes and relatedcompounds via a formal [3+2] cycloaddition. A study of the influence of the aromatic ring substitution pattern on the reaction was carried out.
Determination of Major Aroma Impact Compounds in Fermented Cucumbers by Solid-Phase Microextraction--Gas Chromatography--Mass Spectrometry--Olfactometry Detection
作者:R. T. Marsili、N. Miller
DOI:10.1093/chromsci/38.7.307
日期:2000.7.1
Purge-and-trap, solid-phase extraction, and solid-phase microextraction-gas chromatography-mass spectrometry (SPME—GC—MS) sample preparation techniques for the analysis of odor impact chemicals in fermented cucumber brine are compared. SPME—GC—MS is coupled with detection frequency olfactometry experiments to determine key impact odor compounds in the brine. The most potent odorants that define the typical characteristic brine aroma are trans-4-hexenoic acid and cis-4-hexerioic acid. Confirmation of key impact odorants in brine is confirmed by recombination experiments.