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To study the behavioral role of neurons containing the D1 dopamine receptor (D1ϩ), we have used a genetic neurostimulatory approach. We generated transgenic mice that express an intracellular form of cholera toxin (CT), a neuropotentiating enzyme that chronically activates stimulatory G-protein (G s ) signal transduction and cAMP synthesis, under the control of the D1 promoter. Because the D1 promoter, like other CNSexpressed promoters, confers transgene expression that is regionally restricted to different D1ϩ CNS subsets in different transgenic lines, we observed distinct but related psychomotor disorders in different D1CT-expressing founders. In a D1CT line in which transgene expression was restricted to the following D1ϩ CNS regions-the piriform cortex layer II, layers II-III of somatosensory cortical areas, and the intercalated nucleus of the amygdala-D1CT mice showed normal CNS and D1ϩ neural architecture but increased cAMP content in whole extracts of the piriform and somatosensory cortex. These mice also exhibited a constellation of compulsive behavioral abnormalities that strongly resembled human cortical-limbic-induced compulsive disorders such as obsessive-compulsive disorder (OCD). These compulsive behaviors included episodes of perseverance or repetition of any and all normal behaviors, repetitive nonaggressive biting of siblings during grooming, and repetitive leaping. These results suggest that chronic potentiation of cortical and limbic D1ϩ neurons thought to induce glutamatergic output to the striatum causes behaviors reminiscent of those in human cortical-limbic-induced compulsive disorders.

We derive closed form expressions and limiting formulae for a variety of functions of a permutation resulting from repeated riffle shuffles. The results allow new formulae and approximations for the number of permutations in Sn with given cycle type and number of descents. The theorems are derived from a bijection discovered by Gessel. A self-contained proof of Gessel's result is given.

A cyclic electrochemical technique was developed which enables rapid, high-throughput extraction of important kinetic parameters from one-dimensional artificial pit (lead-in-pencil) electrode experiments. This approach combined methods for pit initiation and propagation with kinetic measurements at a series of pit depths to measure two key kinetic parameters -the pit stability product under a salt film (i·x) saltfilm and the repassivation potential E rp -from a single experiment. The entire sequence was cycled and automated for efficient, high-volume data collection and analysis for the case of stainless steel in neutral chloride solution. This method offered advantages in the extraction and interpretation of data from a wide range of pit depths, permitting statistical analysis of the kinetic parameters required for determining the critical conditions for pit stability and repassivation.

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Our results support the hypothesis that FHR responses to strenuous exercise are altered by advancing gestational age and a brief progressive exercise test terminated at a maternal heart rate of 170 beats x min(-1) does not induce fetal distress during a healthy pregnancy.

1993. Responses of woodland caribou (Rangifer tarandus caribou) to clear-cutting in east-central Newfoundland. Can. J. Zool. 71: 487-493. Movements, sex and age structure, and habitat selection of adult woodland caribou (Rangifer tarandus caribou) were examined in relation to clear-cutting on summer range in east-central Newfoundland during [1987][1988][1989][1990]. We obtained 2473 locations of 35 radio-collared caribou during at least two consecutive summers. Locations relative to clearcuts were determined for eight males and 27 females. Distances to existing clearcuts were compared with distances to those same geographic points prior to and following the summer in which clear-cutting occurred. Four males and 10 females maintained similar mean distances from clearcuts, 3 males and 12 females were farther away, and 2 females were closer. Three other females and one male were assumed to be too distant to be affected by clear-cutting. Of those found farther away from clearcuts, females were 2 -3 times farther away than males. Among female caribou that maintained similar mean distances to clearcuts, habitat use during clear-cutting was similar to that before and afterwards. Females displaced by clear-cutting avo.ided open burns and hardwoods and selected mature black-spruce forest, whereas prior to cutting they used habitats in proportion to their availability. Sex and age ratios indicated that significantly fewer females and calves were present near clearcuts than elsewhere in the study area. Our results demonstrate that clear-cutting mature forests on summer range may affect the movements and distribution of woodland caribou. CHUBBS, T. E., KEITH, L. B., MAHONEY, S. P., et MCGRATH, M. J. 1993. Responses of woodland caribou (Rangifer tarandus caribou) to clear-cutting in east-central Newfoundland. Can. J. Zool. 71 : 487-493. Les dkplacements, la rkpartition des sexes, la distribution des ages et le choix des habitats chez des adultes du Caribou des bois (Rangifer tarandus caribou) ont Ct C mis en relation avec la coupe B blanc sur leur aire d'CtC dans le centre-est de Terre-Neuve en 1987 -1990. Trente-cinq caribous, 8 miles et 27 femelles, porteurs d'kmetteurs-radio B collier ont Ct C repCrCs B 2473 reprises sur au moins deux CtCs consCcutifs. Les distances entre la position des animaux et les zones de coupe B blanc ont Ct C mesurCes. Les positions des animaux par rapport aux sites de coupe ont pu Ctre comparCes un an avant et un an aprks la coupe. Quatre males et 10 femelles n'ont pas changC leur position vis-B-vis les zones de coupe, 3 males et 12 femelles s'en sont CloignCs et 2 femelles s'en sont rapprochCes. Les 3 autres femelles et I'autre male Ctaient probablement trop loin pour Ctre affect& par la coupe. Parmi les animaux qui s'Ctaient distanciCs de la zone de coupe, les femelles s'en CtaientCloignCes de 2 B 3 fois plus que les males. Les femelles qui n'avaient pas changC de position continuaient B exploiter les mCmes habitats qu'avant la coupe. Cependant les femelles, qui avai~nt modifiC leur position, Cv...

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