Biological remodelling: Stationary energy, configurational change, internal variables and dissipation

Remodelling is defined as an evolution of microstructure or variations in the configuration of the underlying manifold. The manner in which a biological tissue and its subsystems remodel their structure is treated in a continuum mechanical setting. While some examples of remodelling are conveniently modelled as evolution of the reference configuration (Case I), others are more suited to an internal variable description (Case II). In this paper we explore the applicability of stationary energy states to remodelled systems. A variational treatment is introduced by assuming that stationary energy states are attained by changes in microstructure via one of the two mechanisms--Cases I and II. An example is presented to illustrate each case. The example illustrating Case II is further studied in the context of the thermodynamic dissipation inequality.Comment: 24 pages, 4 figures. Replaced version has corrections to typos in equations, and the corresponding correct plot of the solution--all in Section

Spatial Dynamics Of Vertical And Horizontal Intergovernmental Collaboration

Although researchers have made progress in understanding motivations behind local government collaboration, there is little research that explores the spatial dynamics of such interactions. Does the idea of collaboration travel horizontally, passed from neighbor to neighbor, or is vertical leadership from state, county, or regional actors more important in influencing local governments’ decisions to share resources and functions? What factors influence local governments’ choices to collaborate with their neighbors versus a regional entity, county, or state government? In this article, we investigate the importance of vertical and horizontal influences when local governments decide to collaborate around land use planning. Using data from a survey of Michigan local government officials, we take a spatial statistical approach to answering this question. We find widespread evidence of collaboration at multiple scales, and observe patterns of both horizontal and vertical influence. We also find that contextual factors help to explain these patterns of collaboration.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112248/1/juaf12139.pd

Perspectives on biological growth and remodeling.

The continuum mechanical treatment of biological growth and remodeling has attracted considerable attention over the past fifteen years. Many aspects of these problems are now well-understood, yet there remain areas in need of significant development from the standpoint of experiments, theory, and computation. In this perspective paper we review the state of the field and highlight open questions, challenges, and avenues for further development

Spring and latch dynamics can act as control pathways in ultrafast systems

Ultrafast movements propelled by springs and released by latches are thought limited to energetic adjustments prior to movement and seemingly cannot adjust once movement begins. Even so, across the tree of life, ultrafast organisms navigate dynamic environments and generate a range of movements, suggesting unrecognized capabilities for control. We develop a framework of control pathways leveraging the non-linear dynamics of spring-propelled, latch-released systems. We analytically model spring dynamics and develop reduced-parameter models of latch dynamics to quantify how they can be tuned internally or through changing external environments. Using Lagrangian mechanics, we test feedforward and feedback control implementation via spring and latch dynamics. We establish through empirically-informed modeling that ultrafast movement can be controllably varied during latch release and spring propulsion. A deeper understanding of the interconnection between multiple control pathways, and the tunability of each control pathway, in ultrafast biomechanical systems presented here has the potential to expand the capabilities of synthetic ultra-fast systems and provides a new framework to understand the behaviors of fast organisms subject to perturbations and environmental non-idealities

Writing Philosophy from the Periphery: Lixing as Foundational Empty Signifier in Tang Junyi’s Cultural Consciousness and Moral Reason

This article adopts Ernesto Laclau’s notion of empty signifier to discuss Tang Junyi’s uses of the concept of lixing (‘reason’ or ‘rationality’) in his seminal work Cultural Consciousness and Moral Reason (文化意識與道德理性; 1958). My dual goal, in doing so, is to bring to light the relations of power constitutive of the text’s discourse on lixing and relate them to the problematic of writing philosophy from the periphery. I argue that in this work, lixing’s dual referents—as a translation of ‘reason’ and as denoting a Neo-Confucian faculty to intuit moral truths—allow Tang to inscribe himself in a philosophical field designed to exclude non-Western philosophies, while at the same time enabling him to symbolically relegate Euro-American philosophy to a peripheral position by filling in the notion of lixing with a content that legitimizes his own agenda. Tang could thus authorize his Confucian metaphysics by presenting it as the true content of lixing, understood not only as a universal faculty enabling humanity’s access to all that is universal, but also as a condition sine qua non of for one’s inclusion in the philosophical game. By attempting to co-opt the empty signifier (lixing/reason) for his own purposes, I argue Tang employs one of two possible strategies that can be adopted by those situated at the periphery in order to oppose the hegemon; one that leaves the structure of power relations intact but working in favor of the periphery

Monoclonal antibodies against the structural proteins of viral haemorrhagic septicaemia virus isolates

Abstract. Five VHSV isolates from different host species and Spanish geographical locations and three viral haemorrhagic septicaemia virus (VHSV) international reference serotypes (F1, F2 and 23˙75) were studied by several characterized monoclonal antibodies (MAbs) including a neutralizing MAb to four structural proteins of VHSV. We report here the lack of reaction between anti‐M1 and some of the isolates of VHSV and the homogeneity of most of the isolates with respect to the MAbs tested. The reagents obtained will improve diagnostic tests which currently use polyclonal antibodies. Copyright © 1993, Wiley Blackwell. All rights reserve