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This paper uses time series methods to test the relationship between civic affairs content and audience share for the ABC, CBS, and NBC evening news in the mid-1990s. Because these programs competed in the same market, but varied the amount of their civic affairs coverage, they present an excellent opportunity to analyze this relationship. The study uses hand-coded news abstracts and O.J. Simpson murder trial coverage as separate measures of news content. The study finds that lower levels of civic affairs content and higher levels of O.J. news are associated with greater audience share.  相似文献   
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Abstract: Organic impurity profiling of seized 3,4‐methylenedioxymethamphetamine (MDMA) tablets aims to link tablets to common production sources. Conventionally, organic impurities are extracted from tablets using a liquid–liquid extraction (LLE) procedure prior to analysis by gas chromatography–mass spectrometry (GC‐MS). In this research, the development of an alternative microwave‐assisted extraction/headspace solid‐phase microextraction (MAE/HS‐SPME) procedure is described. The optimal procedure used phosphate buffer (1 M, pH 8), with an HS‐SPME extraction temperature of 70°C for 40 min, using a divinylbenzene/Carboxen?/polydimethylsiloxane (DVB/CAR/PDMS) fiber. Impurities were extracted from seized MDMA exhibits using the MAE/HS‐SPME procedure, as well as HS‐SPME alone, and a conventional LLE procedure. The HS‐SPME procedure was deemed to be the most practical because of the affordability and need for less analyst involvement. Although the LLE was limited in the number of impurities extracted, the procedure is still useful for the extraction of less volatile impurities that are not extracted by HS‐SPME.  相似文献   
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Daily per capita calorie intake in Bangladesh averaged almost 2,100 (kilo)calories in the 1960s but fell to 1,840 in 1972 following the war of independence in 1971, and only by 1987 did it reach 2,000 again. This article examines the long-run relationship between per capita income, food prices and per capita calorie intake using aggregate data for Bangladesh for 1962–97 and the recent cointegration procedure of Johansen et al., which permits structural breaks. Results show that a long-run relationship exists and that the war reduced average calorie intake permanently by 10 per cent. Impulse responses show that income Granger-causes calorie intake but not vice versa.  相似文献   
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