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We developed a process-based model of forest growth, carbon cycling and land-cover dynamics named CARLUC (for CARbon and Land-Use Change) to estimate the size of terrestrial carbon pools in terra firme (nonflooded) forests across the Brazilian Legal Amazon and the net flux of carbon resulting from forest disturbance and forest recovery from disturbance. Our goal in building the model was to construct a relatively simple ecosystem model that would respond to soil and climatic heterogeneity that allows us to study the impact of Amazonian deforestation, selective logging and accidental fire on the global carbon cycle. This paper focuses on the net flux caused by deforestation and forest re-growth over the period from 1970 to 1998. We calculate that the net flux to the atmosphere during this period reached a maximum of � 0.35PgCyr � 1 (1PgC 5 1 � 10 15 gC) in 1990, with a cumulative release of � 7PgC from 1970 to 1998. The net flux is higher than predicted by an earlier study (Houghton et al., 2000) by a total of 1PgC over the period 1989‐1998 mainly because CARLUC predicts relatively high mature forest carbon storage compared with the datasets used in the earlier study. Incorporating the dynamics of litter and soil carbon pools into the model increases the cumulative net flux by � 1PgC from 1970 to 1998, while different assumptions about land-cover dynamics only caused small changes. The uncertainty of the net flux, calculated with a Monte-Carlo approach, is roughly 35% of the mean value (1SD).

Funding was provided by the National Science Foundation under Grant Nos. OCE-9806381, OCE-9940880, and OCE-0095069.

In learning motor skills, different types of information can be utilized to reinforce correct execution of the skill. Over the years, augmented information after the movement (i.e., knowledge of results) has been the most widely studied and has received attention as the most important variable for learning. Recently, however, researchers have begun to focus on modeling or providing information prior to movement as another important aspect of skill learning. The present experiment compared a KR 100% condition with a KR 33% condition, with a final modeling plus KR condition on the acquisition and immediate transfer retention of a timing task. The results showed that all groups reached the same performance level by the end of acquisition. However, over the immediate transfer phase, subjects who had received modeling plus KR during acquisition, increased their errors. Delayed retention produced no significant group effects.

Military courts have had to face the issue of compulsive gambling in criminal court-martial proceedings. The military recently switched from the liberal ALI definition of insanity to the much more stringent standards of the federal Insanity Defense Reform Act. However, military courts have not even allowed in expert testimony, holding the relevance of compulsive gambling has not been generally accepted in the scientific community. The rules involving extenuation or mitigation in sentencing allow much more leeway. Although compulsive gambling cannot be used as the basis for a defense of insanity in military courts, defense lawyers will continue to raise the issue in attempting to obtain lesser punishments for their military clients.

The present study examined the potential interaction effects of using different instructional strategies with intrinsically and extrinsically motivated youths. Subjects whose motivation to participate in sports was either one of intrinsic mastery or extrinsic mastery were randomly placed in one of two instructional groups: knowledge of results (KR) or knowledge of performance (KP). All four groups received a videotaped, modeled demonstration of the skill to be learned, the tennis forehand. Subjects participated in a 3-day acquisition period and a 1-day testing phase, during which both form and outcome scores were recorded. Analysis of acquisition outcome scores yielded no significant differences between motivational orientation or instructional groups. Multivariate analysis of the test phase outcome and form scores revealed significant group differences, as well as significant group-by-motivation and group-by-blocks interactions. Subsequent discriminant analyses indicated that form scores were more affected than outcome scores by the instructional and motivational group manipulations. The interaction results of the test phase supported the prediction of different performance effects as a function of motivational orientation and instructional strategy.

In recent years, researchers have begun to focus attention on how skills are learned from modeling or demonstrations. One point that has received limited interest is the modalities that are presented during demonstrations. Doody, Bird, and Ross (1985) investigated the potency of various modalities for enhancing the cognitive representation for a timing task. During an immediate transfer test, subjects who received either an auditory or auditory plus visual presentation performed better than subjects who received visual demonstrations or physical practice with knowledge of results. Doody et al. interpreted these findings as support for the effectiveness of modeling over physical practice with knowledge of results (KR). Our experiment attempted to extend these findings and determine the potency of modeling independent of KR. Because all subjects in the Doody et al. experiment received KR, it is not known whether subjects can develop an accurate representation from modeling alone. The findings produced the o...

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Read in Section on Ophthalmology, Otology and Laryngology of the American Medical Association, May, 1884, The influences of optical defects are three-fold; first, productive of vision less than normal; second, are productive of certain ocular diseases or render acute attacks of eye disease chronic by their presence; third, there are produced by their presence, headache, nervous symptoms, gastric disturbance, many cases of so-called biliousness and a chain of reflex symptoms due to the accommodative effort. Cases presenting a manifest defect of vision, seek relief by glasses, and are satisfied either partially or fully, as the manifest or total defect is corrected. In cases where ocular disease, or the form of trouble described under the third classification exists, accommodative effort may conceal the defect, which any of the mydriatics will expose and relieve the symptoms if they are the result of the optical condition of the eye; glasses are required to