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Ryan, Christopher J.

Overview
Works: 32 works in 43 publications in 1 language and 120 library holdings
Genres: Maps  Topographic maps  Guidebooks  Academic theses 
Roles: Author
Classifications: GV199.42.M42, 551.554
Publication Timeline
Key
Publications about Christopher J Ryan
Publications by Christopher J Ryan
Most widely held works by Christopher J Ryan
Dynamical classification of Australian thunderstorms by Christopher J Ryan( Book )
4 editions published between 1990 and 1992 in English and Undetermined and held by 20 libraries worldwide
Guide to the Taconic Trail System : in Berkshire County, Massachusetts by Christopher J Ryan( Book )
1 edition published in 1989 in English and held by 9 libraries worldwide
Leominster State Forest ; Wachusett Mtn. & Leominster S.F. map by Christopher J Ryan( Map )
3 editions published between 1986 and 1998 in English and held by 9 libraries worldwide
Quabbin Reservation guide by Christopher J Ryan( Map )
1 edition published in 1986 in English and held by 8 libraries worldwide
Holyoke Range State Park, western section : includes Skinner S.P. & town conservation land trails by Christopher J Ryan( Map )
3 editions published between 1987 and 2001 in English and held by 8 libraries worldwide
Mt. Greylock map : 1986 by Christopher J Ryan( Map )
1 edition published in 1986 in English and held by 7 libraries worldwide
Holyoke Range State Park, eastern section by Christopher J Ryan( Map )
1 edition published in 1985 in English and held by 7 libraries worldwide
Mt. Tom State Reservation : recreation map of Mount Tom and the surrounding region (for hikers, skiers, boaters) by Christopher J Ryan( Map )
1 edition published in 1985 in English and held by 6 libraries worldwide
Quabbin Reservoir guide by Christopher J Ryan( Map )
1 edition published in 1985 in English and held by 4 libraries worldwide
Mt. Toby trail map : for hiking, ski touring, and other outdoors pursuits near the Mt. Toby Reservation by Christopher J Ryan( Map )
2 editions published between 1988 and 1993 in English and held by 4 libraries worldwide
Holyoke Range State Park, eastern section : includes trails on town conservation lands by Christopher J Ryan( Map )
2 editions published between 1989 and 1996 in English and held by 4 libraries worldwide
Trail map of the Holyoke Range, western section : includes Skinner State Park, Hadley, Mass. by Christopher J Ryan( Map )
1 edition published in 1984 in English and held by 3 libraries worldwide
Mt. Toby trail map : for hiking, ski touring, and other outdoor pursuits near the Mt. Toby Reservation by Christopher J Ryan( Map )
1 edition published in 1999 in English and held by 3 libraries worldwide
Connecticut River guide in Massachusetts : a two-sided map for boating, canoeing, fishing, bicycling, and river camping, etc. by Doug Greenfield( Map )
1 edition published in 1991 in English and held by 3 libraries worldwide
Mt Toby trail map for runners, hikers, skiers by Christopher J Ryan( Map )
1 edition published in 1984 in English and held by 3 libraries worldwide
Emergent material properties and shape transformations of fluctuating membranes with adhered proteins by Christopher J Ryan( file )
1 edition published in 2013 in English and held by 3 libraries worldwide
Many processes that occur at biological membranes have been shown to be remarkable displays of molecular coordination and shape transformation. Despite the apparent complexity of these processes, investigations of simplified systems have successfully characterized many ways that these materials can self-organize. Such studies established that proteins may either bend membranes by binding to them along curved structural domains or by inserting into them asymmetrically. One recent study, however, showed that generic clusters of small membrane-adhered proteins that lack these features can nevertheless remodel membranes into highly curved shapes. In this manuscript we use theoretical and computational methods of statistical mechanics to elucidate how a driving force for membrane curvature emerges from the steric effects among such adhered proteins. First, we develop a basic thermodynamic model of the experimental system referenced above, considering the energetic penalty of membrane bending for simple shapes while also introducing the 2-dimensional pressure of the adhered protein layer. We show that increasing the curvature of the underlying membrane effectively increases the area of the adhered protein layer, lowering the associated pressure and entropically stabilizing the composite system at nonzero curvatures. To generate quantitative predictions of curvature as a function of adhered protein concentration, we model the protein layer as a hard disk fluid and compare these results to experimental data. We also use overdamped Langevin dynamics simulations, again considering only volume excluding interactions among proteins, to observe shape transformations and fluctuations of such systems in more complex morphologies. We extend our thermodynamic model to show that cylindrical curvature becomes more stable than spherical curvature at protein densities higher than some critical value. This critical value becomes smaller as membrane area increases, which supports experimental observations and explains why tubules are unstable in simulated systems, which are much smaller. The development of a molecular simulation model for this research was a significant effort, and we discuss this implementation in some detail. We build upon a coarse-grained model previously developed in our research group, however we modify its original functional forms to be smoothly varying and thus stable for dynamical integrators. We also develop consistent coarse-grained models for adhered proteins and for a second lipid type. We then discuss extensions developed for future studies, methods of analysis, and relaxation time scaling for cylindrical configurations. Finally, we show how the adhered protein layer effectively renormalizes the original material properties of the underlying membrane. We begin by theoretically analyzing our composite membrane-protein system in the regime of small but nonzero curvature fluctuations. This analysis yields a form identical to the standard free energy of a bare membrane but with effective expressions for the bending rigidity, surface tension, and spontaneous curvature that are dependent on the density of adhered proteins. As protein density increases, the effective bending rigidity and spontaneous curvature reduces until the system can become unstable. We support these predictions with molecular simulation calculations of the type discussed earlier. These results exemplify the ideas discussed at the start of this manuscript, demonstrating how the emergent characteristics of seemingly complex membranes can sometimes be remarkably folded back into the basic physics of these soft materials. Moreover, since a membrane attachment region alone is sufficient for protein clusters to produce the results presented throughout this work, these results could characterize a new and general way that proteins modify and sculpt membranes during various essential cellular processes
Galaxy interactions and active galactic nuclei in the local universe by Christopher J Ryan( Book )
2 editions published between 2009 and 2010 in English and held by 2 libraries worldwide
Mt. Greylock map : 1993 by Christopher J Ryan( Map )
1 edition published in 1993 in English and held by 2 libraries worldwide
Mt. Greylock map : 2002 by Christopher J Ryan( Map )
1 edition published in 2002 in English and held by 2 libraries worldwide
Mt. Tom Reservation : recreation trail map for hikers, bicyclists, etc. by Christopher J Ryan( Map )
2 editions published between 1990 and 2002 in English and held by 2 libraries worldwide
 
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Alternative Names
Ryan, Chris (Christopher J.)
Languages
English (30)
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