Particulate organic matter transport in the lower Colorado river,South-Western USA

The lower Colorado River from Laughlin, Nevada, to the border with Mexico is one of the most regulated rivers in North America. An analysis of particulate organic matter (POM) transport through the system was made to determine POM concentrations, composition and point of origin, as well as to determine the effect dams had on this transport. Particulate organic matter concentrations generally increased from upstream to downstream, and were dominated by very fine organic detritus (< 25μm size fraction). Reservoirs released more POM than they received during spring and summer, but less during autumn and winter. Reservoirs recycled POM, taking in organic detritus and discharging small limnoplankton. Backwater complexes functioned as filters during storm events, trapping coarse material and releasing fine material. Agricultural drains made only minor contributions of POM, but provided important nutrients for in-channel production of POM. Water diversions forced POM off-channel, whereas sluicing operations reduced inorganic loads in the canals. Despite the presence of six mainstem dams, the lower reaches support a diverse assemblage of detritivorous fishes, similar to that found in the lowermost reaches of natural, unregulated rivers. The food base for this fishery stems from autochthonous production of POM.     

Review of Neuropsychological validation of learning disability subtypes.

Rourke's present edited work, a welcome sequel or "companion volume" to his 1985 book, focuses primarily on evaluating the internal and external validity of existing learning disabilities (LD) typologies within a "confirmatory hypothesistesting framework" initially described by Skinner (1981). Within this framework, studies examining the internal validity of typologies are concerned with issues relating to their reliability and replicability (i.e., the degree to which the typologies' derivation is independent of specific statistical or sampling techniques). External validation studies, on the other hand, attempt to demonstrate that reliably-derived subtypes differ in a meaningful and predictable manner on variables (i.e., external criteria) not initially used to develop the typology. This edited volume will be of interest to research scientists, both within and outside the realm of neuropsychology, interested in classification theory and methods; to clinicians faced with the dual tasks of assessing disabled learners and facilitating rational and productive instructional decisions; and to academics, especially at the college and university level, entrusted with the education of learning-disabled adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The perception of phoneme sequences by monolingual and bilingual elementary school children.

Compared 121 3rd and 4th grade students, some schooled monolingually in either French or English, and some schooled bilingually in both English and French, for their ability to differentially discriminate initial phoneme sequences. This ability was tested with an ABCX discrimination procedure. A significant interaction between method of instruction and category of stimulus sound indicates that the bilingually taught Ss had developed a sensitivity for the sound system of their 2nd language, but that this training had not resulted in a generalized facility in discriminating sound systems by the 4th grade. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Teaching behavioral science to family medicine residents: integrating training into the family practice unit

INTRODUCTION: Physicians need to be well trained in HIV risk assessment interview skills. Little has been written in the literature concerning training methods for this specialized interview. METHODS: One model to teach the HIV risk assessment interview has been developed and has been used to teach third-year medical students. We compared this interactive model, which uses simulated patients to teach HIV Risk Assessment, to a didactic one. Twelve medical residents were taken through either the interactive session or the didactic session. Pre-post changes from questionnaires were calculated to determine any differences in sessions. Also, Objective Structured Clinical Examinations (OSCEs) were used to grade all residents 2 weeks after their sessions. RESULTS: All pre-post changes were calculated and no statistically significant differences were seen (P > 0.50). OSCE interpersonal skills scores and content scores were calculated. The interactive group had statistically significantly higher scores (P < 0.05). CONCLUSION: The data supports the conclusion that an interactive method is more effective to use to train HIV risk assessment interview skills to medical residents when compared to the didactic method.