Functional Brain Networks Develop from a “Local to Distributed” Organization

The mature human brain is organized into a collection of specialized functional networks that flexibly interact to support various cognitive functions. Studies of development often attempt to identify the organizing principles that guide the maturation of these functional networks. In this report, we combine resting state functional connectivity MRI (rs-fcMRI), graph analysis, community detection, and spring-embedding visualization techniques to analyze four separate networks defined in earlier studies. As we have previously reported, we find, across development, a trend toward ‘segregation’ (a general decrease in correlation strength) between regions close in anatomical space and ‘integration’ (an increased correlation strength) between selected regions distant in space. The generalization of these earlier trends across multiple networks suggests that this is a general developmental principle for changes in functional connectivity that would extend to large-scale graph theoretic analyses of large-scale brain networks. Communities in children are predominantly arranged by anatomical proximity, while communities in adults predominantly reflect functional relationships, as defined from adult fMRI studies. In sum, over development, the organization of multiple functional networks shifts from a local anatomical emphasis in children to a more “distributed” architecture in young adults. We argue that this “local to distributed” developmental characterization has important implications for understanding the development of neural systems underlying cognition. Further, graph metrics (e.g., clustering coefficients and average path lengths) are similar in child and adult graphs, with both showing “small-world”-like properties, while community detection by modularity optimization reveals stable communities within the graphs that are clearly different between young children and young adults. These observations suggest that early school age children and adults both have relatively efficient systems that may solve similar information processing problems in divergent ways

Dew as a Source of Plant Moisture

Volume: 6Start Page: 259End Page: 26

A Review of Concepts in Hawaiian Climatology

HAWAII, which is noted for its equable te the lack of great variations between often obscures the importance of day-nd geographic variations in weather. ii owes its relatively uniform climate to ion with respect to the sub-tropical h pressure cell and accompanying ocean cur-The rugged topography causes salient aphic rainfall patterns. The variations in ual rainfall through short horizontal dis-re common knowledge among residents ii. Areas in the mountains immediately d Honolulu receive up to 160 inches an-nually, while at the seashore, 5.5 miles away from the mountains, less than 15 inches is re-corded. On Kauai, the annual mean varies from 450 to 20 inches in a horizontal distance of 12 miles. The changes of greatest economic importance, surprisingly enough, are those that occur be-tween consecutive months and between con-secutive years. The growing of pineapples and of sugar cane represents the two most important industries in the Hawaiian Islands. These in-dustries, which utilize a large proportion of the arable land in the rainfall zone between 20 and 100 inches, have found that the wide variations in rainfall from the mean in consecutive months and consecutive years constitute one of the most critical risks in their operations. ‘Published with the approval of the Director a

Memorandum on Notes on Recent Ground-Water Developments in Arizona

Cover sheet: Memorandum from Luna B. Leopold, to Stewart Udall, "Notes on recent ground-water developments in Arizona," May 7, 196

Memorandum on Notes on Recent Ground-Water Developments in Arizona

Cover sheet: Memorandum from Luna B. Leopold, to Stewart Udall, "Notes on recent ground-water developments in Arizona," May 7, 1962IN REPLY REFER TO: UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY WASHINGTON 25. D. C. May 7, 1962 Memorandum To: Secretary of the Interior Through: Director, Geological Survey(??) Assistant Secretary--Mineral From: Chief Hydraulic Engineer Resources Subject: Notes on recent ground-water developments in Arizona In response to your request of March 21, I am forwarding a manuscript which summarizes recent developments in Arizona relative to ground water. Luna B. Leopold AttachmentEpson Perfection 4870 Photo, 400 dpi, 24 bit, 2,176,652 byte