Central Atlantic Coastal Plain - A Summary of the Geological Evolution of Chesapeake Bay, Eastern United States

The seaward margin of the U.S. Atlantic Coastal Plain has fluctuated through time, from near the Fall Line to near the edge of the present Outer Continental Shelf, owing to changes in relative sea level. The strata that underlie the Coastal Plain were deposited in environments that ranged from fully terrestrial to fully marine. Estuarine environments are critical components of the Coastal Plain; they represent the interface, otherwise known as the shoreline, between the marine and terrestrial depositional systems. The Quaternary evolution of estuaries has important implications for both documenting the history of sea-level changes and interpreting ancient coastal-plain strata. In this paper, we briefly summarize the Quaternary history of the Chesapeake Bay, the largest of the many Coastal Plain estuaries on the Atlantic coast. This summary is based on recent syntheses of a wide variety of data (Colman and others, 1988, 1990; Colman and Mixon, 1988) on the history and evolution of the bay.https://scholarworks.wm.edu/vimsbooks/1114/thumbnail.jp

Quaternary Geology of the Chesapeake Bay

The Chesapeake Bay, which is a classic coastal plain estuary, is located on a trailing edge continental margin. It has a surface area of nearly 6,000 km2 and ranges in width from 8 to 48 km. The morphology of the bay clearly reflects its formation as a response to fluctuating sea level during and following the last major continental glaciation. The shoreline is highly irregular, the tributaries form an intricate dendritic drainage pattern, and a deep axial channel occurs along much of its length (fig. 1). Water depths commonly exceed 30m in this deep channel, which is flanked by broad shallow benches. Overall, the bay is quite shallow and has an average depth _of only 8 m. more....https://scholarworks.wm.edu/vimsbooks/1115/thumbnail.jp

The resistance of randomly grown trees

Copyright @ 2011 IOP Publishing Ltd. This is a preprint version of the published article which can be accessed from the link below.An electrical network with the structure of a random tree is considered: starting from a root vertex, in one iteration each leaf (a vertex with zero or one adjacent edges) of the tree is extended by either a single edge with probability p or two edges with probability 1 − p. With each edge having a resistance equal to 1 omega, the total resistance Rn between the root vertex and a busbar connecting all the vertices at the nth level is considered. A dynamical system is presented which approximates Rn, it is shown that the mean value (Rn) for this system approaches (1 + p)/(1 − p) as n → ∞, the distribution of Rn at large n is also examined. Additionally, a random sequence construction akin to a random Fibonacci sequence is used to approximate Rn; this sequence is shown to be related to the Legendre polynomials and its mean is shown to converge with |(Rn) − (1 + p)/(1 − p)| ∼ n−1/2.Engineering and Physical Sciences Research Council (EPSRC

Comportamento de genótipos de milho safrinha em duas épocas de semeadura em Dourados, MS.

bitstream/item/65362/1/29896.pdfOrganizado por Gessi Ceccon e Luiz Alberto Staut

Biomassa microbiana do solo em cultivo de bananeira consorciada com diferentes espécies de adubos verdes.

JIPE 2013

Social fluidity mobilizes contagion in human and animal populations

International audienceHumans and other group-living animals tend to distribute their social effort disproportionately. Individuals predominantly interact with a small number of close companions while maintaining weaker social bonds with less familiar group members. By incorporating this behavior into a mathematical model, we find that a single parameter, which we refer to as social fluidity, controls the rate of social mixing within the group. Large values of social fluidity correspond to gregarious behavior, whereas small values signify the existence of persistent bonds between individuals. We compare the social fluidity of 13 species by applying the model to empirical human and animal social interaction data. To investigate how social behavior influences the likelihood of an epidemic outbreak, we derive an analytical expression of the relationship between social fluidity and the basic reproductive number of an infectious disease. For species that form more stable social bonds, the model describes frequency-dependent transmission that is sensitive to changes in social fluidity. As social fluidity increases, animal-disease systems become increasingly density-dependent. Finally, we demonstrate that social fluidity is a stronger predictor of disease outcomes than both group size and connectivity, and it provides an integrated framework for both density-dependent and frequency-dependent transmission

Memory and burstiness in dynamic networks

A discrete-time random process is described, which can generate bursty sequences of events. A Bernoulli process, where the probability of an event occurring at time t is given by a fixed probability x, is modified to include a memory effect where the event probability is increased proportionally to the number of events that occurred within a given amount of time preceding t. For small values of x the interevent time distribution follows a power law with exponent −2−x. We consider a dynamic network where each node forms, and breaks connections according to this process. The value of x for each node depends on the fitness distribution, \rho(x), from which it is drawn; we find exact solutions for the expectation of the degree distribution for a variety of possible fitness distributions, and for both cases where the memory effect either is, or is not present. This work can potentially lead to methods to uncover hidden fitness distributions from fast changing, temporal network data, such as online social communications and fMRI scans

Adolescent self-control predicts midlife hallucinatory experiences:40-year follow-up of a national birth cohort

Associations between self-control in adolescence and adult mental health are unclear in the general population; to our knowledge, no study has investigated self-control in relation to psychotic-like symptoms