The assay of plasma very long chain fatty acids (VLCFAs), developed in our laboratory in 1981, has become the most widely used procedure for the diagnosis of X‐linked adrenoleukodystrophy (X‐ALD) and other peroxisomal disorders. We present here our 17 years' experience with this assay. Three VLCFA parameters, the level of hexacosanoic acid (C26:0), the ratio of C26:0 to tetracosanoic acid (C24:0), and of C26:0 to docosanoic acid (C22:0), were measured in 1,097 males (hemizygotes) with X‐ALD, 1,282 women heterozygous for this disorder, including 379 obligate heterozygotes, 797 patients with other peroxisomal disorders, and 29,600 control subjects. All X‐ALD hemizygotes who had not previously received Lorenzo's oil or a diet with a high erucic acid content had increased VLCFA levels, but the application of a discriminant function based on all three measurements is required to avoid the serious consequences of a false‐negative result. VLCFA levels are increased at day of birth, thus providing the potential for neonatal mass screening, are identical in the childhood and adult forms, and do not change with age. Eighty‐five percent of obligate heterozygotes had abnormally high VLCFA levels, but a normal result does not exclude carrier status. VLCFA levels were increased in all patients homozygous for Zellweger syndrome, neonatal adrenoleukodystrophy, infantile Refsum's disease, and in patients with deficiencies of peroxisomal acyl‐coenzyme A oxidase, bifunctional enzyme, and 3‐oxoacyl‐coenzyme A thiolase. In these patients the degree of VLCFA excess correlated with clinical severity. Ann Neurol 1999;45:100–110

We conducted a food supplementation field experiment to test two hypotheses: (1) fecundity of the fishing spider Dolomedes triton is limited by a shortage of prey, and (2) the increased movement of adult female D. triton exhibited upon maturation is a foraging adaptation to lessen the impact of food limitation on egg production. Free ranging, uniquely marked adult female fishing spiders were assigned either to a food-supplemented group that received crickets in addition to their natural diet, or to a control group. Juvenile female spiders were also marked and their movement patterns were recorded, but juveniles were not offered supplemental food. Food-supplemented adult females gained weight at a faster rate and hatched more than twice as many offspring as control females. Adult females in the control group moved greater distances per day than did juvenile females. Supplemented adult females moved shorter distances per day than control females, and the movement pattern of fed adults did not differ from that of juveniles. These results support the hypotheses that adult female D. triton are food limited, and that the increased movement of adult females is a switch in foraging behavior that occurs during the reproductive period. Our finding that natural prey shortages limit egg production contrasts with laboratory-based studies of food limitation in the genus Dolomedes, and contradicts a basic assumption of a recent hypothesis that sexual cannibalism in Dolomedes is non-adaptive. These discrepancies highlight the importance of insights gained from field experiments with natural populations.

Three methods of analysis were used to determine the effects of the combination of counseling with fluoxetine (20, 40, or 60 mg) and "active" placebo (diphenhydramine, 12.5 mg) randomly assigned. Forty-five cocaine-only dependent subjects were treated as outpatients with "interpersonal" counseling, medication, and drug use monitoring three times per week for up to 12 weeks. Treatment effects were analyzed: first, by comparing the three original assignments and placebo; second, by comparing the placebo group to fluoxetine subjects with detectable fluoxetine/norfluoxetine blood levels and those with no detectable medication blood level; third, by examining relapse prevention versus use cessation through stratifying the subjects into four groups according to fluoxetine or placebo assignment and initial urine cocaine positivity or negativity. All three analyses showed improvement on some measures over time regardless of group assignment. The 60-mg fluoxetine group showed least effectiveness, the group with detectable blood levels had less cravings, and the fluoxetine subjects who were abstinent at the start of treatment were somewhat less likely to avoid relapse than those on placebo.

Previous studies indicate that monkey pure tone frequency discrimination is quantitatively and qualitatively very different from that of humans: Monkey DLs at 1.0 and 2.0 kHz are up to 20 times larger than human DLs, and monkeys DLs increase as sensation level increases, in contrast to human DLs [Sinnott et al., J. Acoust. Soc. Am. 78, 1977-1985 (1985); Sinnott et al., J. Comp. Psychol. 101, 126-131 (1987)]. These results led to an hypothesis that monkey frequency discrimination is more dependent upon "rate" coding than is that of humans. The present study compared monkey and human DLs for formant frequency changes along three synthetic vowel continua /I-i/, /ae-epsilon/, and /a-v/. Here, monkey DLs for formants near 1.0 and 2.0 kHz (32-48 Hz) were only about two to three times larger than human DLs (11-21 Hz), and both monkeys and humans exhibited relatively similar, flat sensation level functions. Taken together, these data indicate that monkey and human frequency discrimination is more similar in the case of a complex vowel stimulus than in the case of a simple pure tone stimulus. Results are discussed in relation to "rate" versus "temporal" coding of tones and vowels in the auditory system.

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In Part 1, we analyzed alarm calls produced by captive vervets (Cercopithecus aethiops) in response to naturally occurring stimuli. Females and juveniles regularly alarm called to airplanes, birds, and barking dogs. Juvenile females accounted for 60% of these alarm calls. In Part 2, we isolated several monkeys from the colony and presented them with life-sized silhouettes of a leopard, snake, eagle, baboon, vervet, and goose. Adult monkeys alarm called more than did juveniles. Alarm calls were elicited by leopard, snake, baboon, and vervet silhouettes, but none were elicited by eagle or goose silhouettes. Some leopard and snake alarm calls matched those recorded in the wild in the context of the vervets' natural predators. Results indicate that silhouette stimuli are a useful technique for eliciting monkey vocalizations in the laboratory.

Three experiments compared the similarities and differences in attacks on crickets by two species of laboratory-raised cricetid mice, Peromyscus maniculatus bairdi and P. leucopus noveboracensis. In Experiment 1 moderately prey-experienced 1.5-year-old mice of both species concentrated attacks on the crickets' dorsal head. P. leucopus also produced considerable damage to the thorax and showed a greater effect of sessions on the location and latency of attack. In Experiment 2 prey-naive .4-to .8-year-old mice of both species initially damaged crickets randomly and were slow to attack, but after two sessions both species attacked rapidly and displayed the same focus on the dorsal head shown in Experiment 1. However, P. leucopus did not display the thoracic focus shown by this species in Experiment 1. In Experiment 3 the P. leucopus from Experiment 2 were retested at 1.5 years of age without further predatory experience and showed the thoracic focus of attack found in Experiment 1. Young adults of both species markedly and similarly increased the speed and focus of predatory attacks on crickets after limited experience. The attack characteristics of older P. maniculatus differed very little from those of experienced young adults, whereas the attack characteristics of P. leucopus changed as a function of both age and subsequent test experience.

Administrators at 400 colleges and universities were surveyed for information regarding their schools' current or proposed policies for the urine drug testing of faculty, nonfaculty employees, and students. Three hundred seven schools (77%) responded regarding their testing policies for employees and applicants for employment, including faculty and nonfaculty; 332 (83%) responded with respect to students. Twenty-five schools reported testing one or more of these groups. None of the schools reported randomly testing applicants for either faculty or nonfaculty positions, and none tested all applicants for all positions. Fewer than 7% of the colleges and universities surveyed reported that they tested urine of employees and applicants for employment to detect drug use. In those institutions that carried out tests, the tests were most often directed toward particular types of workers. Student testing was limited to approximately 2% of the 332 responding institutions.