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The neuroanatomical correlates of attentive listening were investigated with functional magnetic resonance imaging and an attention task in which listeners responded only to words that combined two specific attributes of voice and semantic content. This task was performed under two different attentive listening conditions: (i) diotically, with words presented sequentially, and (ii) dichotically, with male and female voices presented simultaneously but segregated to different ears. For both conditions, functional magnetic resonance imaging revealed bihemispheric but right-lateralized activity patterns in mid-prefrontal, anterior cingulate, and inferior parietal areas, as well as significant anterior insular and subcortical activation. Manipulating attentional demands under different listening conditions revealed an important role for right anterior insula, striatum, and thalamus in the regulation of attentive listening to spoken language.

Exotic species invasions create almost ideal conditions for promoting evolutionary diversification: establishment of allopatric populations in new environmental conditions; altered ecological opportunities for native species; and new opportunities for hybridization between previously allopatric taxa. Here, we review recent studies of the evolutionary consequences of species invasions, revealing abundant and widespread examples of exotic species promoting evolutionary diversification via increased genetic differentiation among populations of both exotic and native species and the creation of new hybrid lineages. Our review indicates that, although the well-documented reductions to biodiversity caused by exotic species might outweigh the increases resulting from diversification, a complete understanding of the net effects of exotic species on biodiversity in the long term will require consideration of both.

Human-mediated species invasions are a significant component of current global environmental change. There is every indication that the rate at which locations are accumulating non-native species is accelerating as free trade and globalization advance. Thus, the need to incorporate predictive models in the assessment of invasion risk has become acute. However, finding elements of the invasion process that provide consistent explanatory power has proved elusive. Here, we propose propagule pressure as a key element to understanding why some introduced populations fail to establish whereas others succeed. In the process, we illustrate how the study of propagule pressure can provide an opportunity to tie together disparate research agendas within invasion ecology.

Theory suggests that introduction effort (propagule size or number) should be a key determinant of establishment success for exotic species. Unfortunately, however, propagule pressure is not recorded for most introductions. Studies must therefore either use proxies whose efficacy must be largely assumed, or ignore effort altogether. The results of such studies will be flawed if effort is not distributed at random with respect to other characteristics that are predicted to influence success. We use global data for more than 600 introduction events for birds to show that introduction effort is both the strongest correlate of introduction success, and correlated with a large number of variables previously thought to influence success. Apart from effort, only habitat generalism relates to establishment success in birds.

Objectives: To evaluate the effects of MK-0677, an orally active growth hormone (GH) secretagogue, on functional recovery from hip fracture in previously mobile older individuals., Design: Placebo-controlled, randomized, double-blind trial., Setting: Thirteen medical centers in England, Sweden, Denmark, Belgium, Switzerland, Canada, and the United States. Patients were recruited between 3 and 14 days postoperatively, or no more than 18 days postfracture, at acute care hospitals and rehabilitation centers., Participants: One hundred sixty-one hip-fracture patients were enrolled. Entry criteria included consenting hip-fracture patients who were aged 65 and older and who were ambulatory before their fracture, medically stable postoperatively, and mentally competent. Patients were excluded if they had multiple fractures or severe trauma, diabetes mellitus, cancer, uncontrolled hypertension, congestive heart failure, or total hip replacement in the involved extremity., Intervention: Random assignment to 6 months of daily treatment with MK-0677 or placebo. Patients were followed for an additional 6 months after completion of therapy., Measurements: Change from Week 6 to Week 26 in a panel of functional performance measures. Additional outcome measures included change in the Sickness Impact Profile for Nursing Homes (SIP-NH), the ability to live independently, and insulin-like growth factor I (IGF-I) levels., Results: MK-0677 treatment increased serum IGF-I levels by 84% (95% confidence interval (CI)=63-107), compared with an increase of 17% (95% CI=8-28) on placebo. There were no significant differences between MK-0677 and placebo in improvement in functional performance measures or in the overall SIP-NH score. Although MK-0677 patients showed greater improvement relative to placebo in three of four lower extremity functional performance measures, in the physical domain of the SIP, and in the ability to live independently, these differences were not statistically significant., Conclusion: Although MK-0677 treatment increased serum IGF-I, it is uncertain whether clinically significant effects on physical function were achieved. Measuring function in clinical trials in hip-fracture patients is difficult because of the lack of validated outcome measures, high variability, and the lack of a baseline assessment. Present functional performance measures may not be sufficiently responsive for use as the primary endpoint of small intervention studies; alternatively, stimulation of GH may not result in significant functional improvement.

Human activities are not random in their negative and positive impacts on biotas. Emerging evidence shows that most species are declining as a result of human activities ('losers') and are being replaced by a much smaller number of expanding species that thrive in human-altered environments ('winners'). The result will be a more homogenized biosphere with lower diversity at regional and global scales. Recent data also indicate that the many losers and few winners tend to be non-randomly distributed among higher taxa and ecological groups, enhancing homogenization.

Ecologists have long attempted to predict the success of species that are introduced into foreign environments. Some have emphasized qualities intrinsic to the species themselves, whereas others have argued that extrinsic forces such as competition may be more important. We test some of the predictions made by both the extrinsic and intrinsic hypotheses using passeriform birds introduced onto the island of Saint Helena. We found direct evidence that extrinsic forces are more important predictors of successful invasion. Species introduced when fewer other species were present were more likely to be successful. In a direct test of the alternative hypothesis that intrinsic forces play a more prominent role in success or failure, we found a tendency for species which successfully established on Saint Helena to be also successful when introduced elsewhere. However, the vast majority of species unsuccessful at establishing on Saint Helena had probabilities of success outside Saint Helena of 50% or greater, making this result somewhat equivocal. Finally, we found no evidence to support the hypothesis that species that are successful early are those that are intrinsically superior invaders. These results are consistent with similar analyses of the introduced avian communities on Oahu, Tahiti, and Bermuda.

Contrary to the view taken by some, individual species matter: they are valuable for their contribution to the stability of the ecosystems they inhabit.

A loam soil treated with atrazine at rates of 10, 30, and 100 microgram/g soil resulted in increased populations of actinomycetes, bacteria, and fungi over those in non-treated soil. The increases were in proportion to the amount of atrazine and persisted for at least 2 months. Living actinomycete amd fungal mycelia were incubated for 48 h in distilled water, nutrient broth, or soil containing 5 microgram/ml (g) of the herbicide. Actinomycete and fungal mycelia accumulated atrazine from water to concentrations up to 87-fold and 132-fold, respectively, over that in the ambient medium. The maximum accumulation from soil by actinomycete mycelia was 26-fold and by fungal mycelia 13-fold. Fungi accumulated little or no atrazine from a nutrient medium whereas actinomycetes accumulated up to 13-fold. Dead mycelia usually did not accumulate atrazine in excess of the ambient concentration. Mycelium of Sclerotium rolfsii growing in a nutrient medium containing 20 microgram atrazine/ml accumulated 157 microgram/g wet weight after 8 days. Sclerotia subsequently produced after transfer of similar mats to soil contained 550 microgram/g wet weight.

The Holtzman Ink Blot Test was administered to 5- to 6-year-old children and analyzed for movement response. The range and frequency of movement response in both an original and replication study are significantly greater than would have been anticipated for this age group based upon available normative data. NO significant differences were found in the frequency of Human Movement and Animal Movement responses. No sex difference among subjects was found in the range and frequency of movement responses produced. These new findings call into question previously reported data as well as some of the theoretical presumptions underlying the production of movement responses by young children.

Agar media made with 0.4% colloidal chitin plus mineral salts and adjusted to pH 8.0 was superior to four other commonly used media for the isolation and enumeration of actinomycetes from water samples. More actinomycetes developed on chitin agar, and the development of bacteria and fungi was suppressed. Frozen and vacuum-dried chitin from aqueous colloidal suspensions was finely divided and gave results comparable to those obtained with media prepared from colloidal suspensions.

The effect of fantasy behavior, fantasy predisposition, age, and sex upon direction of aggression in children was assessed in 57 kindergarten boys and girls. Ss from low to high levels of assessed fantasy predisposition were randomly designated as experimental or control. All Ss were exposed to an imposed frustrating condition. The experimental group was then exposed to a condition designed to elicit spontaneous fantasy behavior; the control group was exposed to a condition designed to be incompatible with fantasy. All Ss were then assessed for direction of aggression. Children who engaged in fantasy behavior following frustration were significantly more extrapunitive than control Ss (p less than .05); the findings did not support either the premise that fantasy results in drive-reduction or that fantasy results in the turning inward upon the self of hostile drive manifested by increased intropunitiveness. Age was found to be significantly but negatively correlated with extrapunitiveness (p less than .05).

Movement responses by 5 1/2- to 6 1/2-year-old children on the Holtzman Inkblot Test were reported on by Lockwood et al. in volume 45 of this Journal. Criticism of the findings discussed in that article by J. Swartz, Reinehr, and C. Swartz was published in the December, 1981, volume of the Journal. The present article rebuts their criticism and emphasizes the significance of the original findings which reflect new and highly discrepant normative M response data from that previously available.

Sensitivity of conidia of Cochliobolus victoriae to fungistasis decreased markedly following incubation on moist sand for at least 1 h. Germination was greater on Conover loam or on sand being leached with water than on an alkaline clay loam soil known to produce a volatile fungistatic substance. Evolution of 14CO2 began within 3 min after [14C]glucose was applied to the soils; the rate of 14CO2 evolution was faster with Conover loam. Germination of Thielaviopsis basicola conidia per unit of glucose remaining in agar discs initially containing 0-1% glucose, was lower for discs incubated on the clay loam soil than on Conover loam, and was greatest on a bed of sand undergoing aqueous leaching. Germination of ascospores of Neurospora tetrasperma and conidia of C. victoriae was suppressed on discs of washed, Purified Agar or polyacrylamide gel incubated on or over the clay loam soil, but no suppression resulted when discs were incubated on Conover loam. Extensive aeration of either soil did not remove its fungistatic effect. Fungistasis in Conover loam appears to be caused primarily by nutrient deprivation, whereas volatile fungistatic substances may play a major role in the clay loam soil.

In culture, most of the actinomycetes and filamentous fungi tested degraded PCNB; several actinomycetes dechlorinated DDT to DDD, but no microorganism degraded dieldrin. Streptomyces aureofaciens degraded PCNB to pentachloroaniline.