Positional analysis and determination of triacylglycerol structure ofArgania spinosa seed oil

The distribution of fatty acids between the sn-1, sn-2 and sn-3 positions of triacylglycerols fromArgania spinosa seed oil of Morocco has been determined. Saturated fatty acids showed a preference for external positions. The sn-1 position contained slightly more palmitic acid than the sn-3 position, whereas stearic acid was preferentially esterified at the sn-3 position. Linoleic acid occurred predominantly in the sn-2 position with lesser amount evenly distributed between the sn-1 and the sn-3 positions, as generally found in vegetable oils. Oleic acid was distributed with a slight preference shown for the internal position, whereas the distribution between the external positions revealed a slight preference for the sn-1 position. The distribution of the triacylglycerols determined from high-performance liquid chromatography (HPLC) is at variance with that calculated from the 1-random 2-random 3-random distribution theory. This is particularly true for trioleoyl and trilinoleoylglycerols. In contrast, the agreement between theory and experiment is good for triacylglycerols containing two oleoyl and one linoleoyl chains, one oleoyl, one linoleoyl and one palmitoyl chains or one oleoyl, one palmitoyl, and one stearoyl chains.     

Comments, with reply, on `2-dimensionalconsecutive-k-out-of-n:F models' by A.A. Salvia andW.C. Lasher

The commenter corrects an error in the upper bound calculated in the above-titled paper (see ibid., vol.9, p. 382-5, Aug. 1990) for the reliability of the system considered. The authors acknowledge the correction and point out that it does not affect the validity of the results shown in figures 2-6     

LSD and d-amphetamine effects on fixed interval responding in the rat

A sixty-eight-year-old male was found to have renal carcinoma after seven months of constitutional symptoms. Initial study of the patient showed a puzzling array of laboratory abnormalities. These led initially to a search for gastrointestinal malignancy and then later to consideration of multiple myeloma. This case serves as a reminder of the propensity of early renal carcinoma to produce striking constitutional symptoms and marked hematologic and serum protein abnormalities. These may occur in the absence of metastases and are frequently reversible as shown in this case with resection of the primary lesion.     

Chronic voluntary nicotine drinking enhances nicotine palatability in rats.

Examined the response of rats to nicotine (NI) solutions with the brief-exposure, taste reactivity (TR) test, and a 2-bottle, 24-hr preference test. Naive nondeprived Ss were administered intraoral infusions of distilled water and 1 μg/ml, 5 μg/ml, 10 μg/ml, 25 μg/ml, 50 μg/ml, and 100 μg/ml NI. NI solutions up to a concentration of 50 μg/ml elicited a number of ingestive TR responses similar to that by water. Ingestive responses significantly decreased and aversive TR responses significantly increased in response to 100 μg/ml nicotine. On the basis of these results, 2-bottle preferences for water vs 1 μg/ml, 5 μg/ml, and 0 μg/ml (water control group) NI were measured in 3 groups of naive Ss. Ss initially showed an equal preference for 0 μg/ml and 1 μg/ml NI. After 16 days of exposure, however, Ss developed a significant preference for 1 μg/ml NI. The preference ratio for 5 μg/ml NI significantly increased during the experiment, but the preference ratio remained significantly less than that for 1 μg/ml and 0 μg/ml NI solutions. Last, TR responses elicited by intraoral infusions of 1 μg/ml and 5 μg/ml NI were then measured in these Ss having had the 2-bottle experience. Ss showing a 2-bottle preference for the 1 μg/ml NI solution displayed significantly more ingestive TR responses to 1 μg/ml and 5 μg/ml NI than did the control Ss. Data indicate that prolonged voluntary access to NI results in an increased preference for NI and modifies the immediate oral/gustatory reactivity of the Ss to NI. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nicotine effects on dopamine clearance in rat nucleus accumbens

In vivo voltammetry was used to measure the clearance to exogenously applied dopamine (DA) in the nucleus accumbens following acute systemic nicotine administration in urethane-anesthetized rats. The IVEC-5 system was used for continuous in vivo electrochemical measurements. A finite amount of DA was pressure-ejected (25-100 nl, 200 microM barrel concentration) at 5-min intervals from micropipettes (tip diameter, 10-15 microns) positioned 250 +/- 50 microns from the recording electrode. The peak DA concentration after each DA ejection was significantly decreased in rats following nicotine, but not in rats given saline. In addition, when mecamylamine was administered 20 min before nicotine it clearly antagonized nicotine effects. These results suggest that nicotine may actually facilitate DA transporter systems within the nucleus accumbens.     

Reliability bounds and direct computation of the reliability of a consecutive k-out-of-n:F system with Markov dependence

We propose bounds and direct computation of the reliability of a consecutive k-out-of-n:F system, in the case where each component can have only two states (good or failed) and the sequence of the states of the components forms a Markovian chain. Some interesting deterministic properties are also given.