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Work Suggesting (work + suggesting)
Selected AbstractsInhibitory functioning across ADHD subtypes: Recent findings, clinical implications, and future directionsDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 4 2008Zachary W. Adams Abstract Although growing consensus supports the role of deficient behavioral inhibition as a central feature of the combined subtype of ADHD (ADHD/C; Barkley 1997 Psychol Bull 121:65,94; Nigg 2001 Psychol Bull 127:571,598), little research has focused on how this finding generalizes to the primarily inattentive subtype (ADHD/I). This question holds particular relevance in light of recent work suggesting that ADHD/I might be better characterized as a disorder separate from ADHD/C (Diamond 2005 Dev Psychopathol 17:807,825; Milich et al. 2001 Clin Psychol Sci Pract 8:463,488). This article describes major findings in the area of inhibitory performance in ADHD and highlights recent research suggesting important areas of divergence between the subtypes. In particular, preliminary findings point to potential differences between the subtypes with respect to how children process important contextual information from the environment, such as preparatory cues that precede responses and rewarding or punishing feedback following behavior. These suggestive findings are discussed in the context of treatment implications, which could involve differential intervention approaches for each subtype targeted to the specific deficit profiles that characterize each group of children. Future research avenues aimed toward building a sound theoretical model of ADHD/I and a better understanding of its relation to ADHD/C are also presented. Specifically, investigators are encouraged to continue studying the complex interplay between inhibitory and attentional processes, as this area seems particularly promising in its ability to improve our understanding of the potentially distinct pathologies underlying the ADHD subtypes. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:268,275. [source] PHYLOGEOGRAPHIC STRUCTURE AND CRYPTIC SPECIATION IN THE TRANS-ANTARCTIC MOSS PYRRHOBRYUM MNIOIDESEVOLUTION, Issue 2 2003Stuart F. McDaniel Abstract Many bryophyte species have distributions that span multiple continents. The hypotheses historically advanced to explain such distributions rely on either long-distance spore dispersal or slow rates of morphological evolution following ancient continental vicariance events. We use phylogenetic analyses of DNA sequence variation at three chloroplast loci (atpB-rbcL spacer, rps4 gene, and trnL intron and 3,spacer) to examine these two hypotheses in the trans-Antarctic moss Pyrrhobryum mnioides. We find: (1) reciprocal monophyly of Australasian and South American populations, indicating a lack of intercontinental dispersal; (2) shared haplotypes between Australia and New Zealand, suggesting recent or ongoing migration across the Tasman Sea; and (3) reciprocal monophyly among Patagonian and neotropical populations, suggesting no recent migration along the Andes. These results corroborate experimental work suggesting that spore features may be critical determinants of species range. We use the mid-Miocene development of the Atacama Desert, 14 million years ago, to calibrate a molecular clock for the tree. The age of the trans-Antarctic disjunction is estimated to be 80 million years ago, consistent with Gondwanan vicariance, making it among the most ancient documented cases of cryptic speciation. These data are in accord with niche conservatism, but whether the morphological stasis is a product of stabilizing selection or phylogenetic constraint is unknown. [source] The role of food supply in the dispersal behaviour of juvenile Tawny Owls Strix alucoIBIS, Issue 2 2003C. F. Coles We investigated the effects of food supply on decisions made by dispersing juvenile Tawny Owls Strix aluco in Kielder Forest, Northumberland, in 1996 and 1997. Field Voles Microtus agrestis were the main food of the owls and clear-cuts the main habitat for voles. A vole sign index was used to estimate vole abundance. In areas near to roosting owls, mean vole densities were 83 and 115 ha,1 in 1996 and 1997, respectively. The prediction that birds would perform area-restricted searches when prey was more abundant was not confirmed. Moreover, we found no evidence that juveniles avoided conspecifics. Owls appeared to have an imperfect knowledge of the environment as they responded to variability in Field Vole densities by altering the time spent in different areas rather than by moving to areas with successively greater vole densities. Vole abundance explained 25.7% of the variation in the time spent in different areas. Movements did not decrease with time after dispersal, although the detection of such movements was prone to error. This study supports recent work suggesting that although dispersal may be initiated by a variety of proximate and ultimate factors, individual decisions made during dispersal may depend partly on environmental conditions encountered during the process itself. [source] Forest elephant (Loxodonta africana cyclotis) stature in the Réserve de Faune du Petit Loango, GabonJOURNAL OF ZOOLOGY, Issue 4 2003Bethan J. Morgan Abstract The stature of forest elephants Loxodonta africana cyclotis was determined at the Petit Loango Reserve over 14 months from January to December 1998 and May to June 1999 using three measures: shoulder height, hind footprint length and boli diameter. The shoulder height of 53 identified elephants was measured using photogrammetric methods. The minimum estimated shoulder height was 69 cm from a young calf, and the tallest animal was 216 cm. Hind footprint length and boli diameter data were collected from unidentified individuals. The minimum footprint size was 12.5 cm and the largest 35.3 cm. Boli diameter ranged from 4.0 to 16.0 cm. A comparison of the size categories with those of savanna elephants in Amboseli National Park, Kenya, suggested a similar distribution of size, age and population structure, despite a marked difference in overall stature. These are the first data for measures of African forest elephant size compared to African savanna elephant size. Such data may add morphological evidence supporting recent genetic work suggesting that African forest elephants be re-classified as a distinct species from the African savanna elephant. [source] Fatal Passenger Vehicle Crashes With At Least 1 Driver Younger Than 15 Years: A Fatality Analysis Reporting System StudyTHE JOURNAL OF RURAL HEALTH, Issue 2 2007Larry Frisch MD ABSTRACT:,Context: A small number of fatalities continue to occur due to motor vehicle crashes on highways in which at least 1 passenger vehicle (automobile, van, or small truck) is driven by a child younger than 15 years. Purpose: The purpose of this study was to extend previous work suggesting that such crashes occur frequently in the Southern states and have relatively high rates in rural areas in the South and Great Plains. Methods: This study utilizes data for the 5-year period 1999-2003 from the National Highway Transportation Safety Administration's online Fatality Analysis Reporting System. All cases were identified in which at least 1 conventional passenger vehicle in a fatal crash was being driven by a child younger than 15 years. Findings: During the 5-year period, 350 fatal crashes occurred with at least 1 driver younger than 15 years involved. Twenty-one of these drivers were licensed (11) or driving with a learner's permit (10). A total of 987 individuals in 419 vehicles were involved in these crashes, and 402 deaths resulted (1.16 deaths/crash). These crashes occurred primarily in Texas, Florida, Arkansas, and Arizona, but the highest rates per 100,000 children were found in North and South Dakota and predominantly in a band of Intermountain and Plains states. There was a strong correlation between crash rates and several measures of rurality. Conclusions: Crashes involving young, largely unlicensed, drivers account for about 70 deaths yearly. [source] | ||||||||||