The Origin of Life: Models and Data.

A general framework for conventional models of the origin of life (OOL) is the specification of a 'privileged function.' A privileged function is an extant biological function that is excised from its biological context, elevated in importance over other functions, and transported back in time to a primitive chemical or geological environment. In RNA or Clay Worlds, the privileged function is replication. In Metabolism-First Worlds, the privileged function is metabolism. In Thermal Vent Worlds, the privileged function is energy harvesting from chemical gradients. In Membrane Worlds, the privileged function is compartmentalization. In evaluating these models, we consider the contents and properties of the Universal Gene Set of life, which is the set of orthologous genes conserved throughout the tree of life and found in every living system. We also consider the components and properties of the Molecular Toolbox of Life, which contains twenty amino acids, eight nucleotides, glucose, polypeptide, polynucleotide, and several other components. OOL models based on privileged functions necessarily depend on "takeovers" to transition from previous genetic and catalytic systems to the extant DNA/RNA/protein system, requiring replacement of one Molecular Toolbox with another and of one Universal Gene Set with another. The observed robustness and contents of the Toolbox of Life and the Universal Gene Set over the last 3.7 billion years are thought to be post hoc phenomena. Once the takeover processes are acknowledged and are reasonably considered, the privileged function models are seen to be extremely complex with low predictive power. These models require indeterminacy and plasticity of biological and chemical processes

Leading in Complex Political Environments: What We Are Learning from Superintendents of Education

This working paper examines some of the key issues and challenges confronting some of the most significant actors in American political affairs—superintendents of education—and explores how they can drive meaningful educational reform through exercising capable leadership to implement bold new actions in the face of overwhelming demands. Over the past two years, my colleagues and I at the Center for Public Leadership, in collaboration with the Harvard Graduate School of Education, have been working with twelve superintendents from large urban districts across the country in attending to these leadership challenges. We have learned a lot from this process about the demands of leadership in complex political environments, particularly as it pertains to educational reform. This paper touches on some of these insights and also raises some important research questions that need further investigation. In 2000 the Wallace–Reader’s Digest Funds asked the Center for Public Leadership to design a program that enhances the capacity of superintendents to exercise leadership in this complex political setting. They felt strongly that a new kind of educational leadership program was called for—one that addressed how to operate effectively in highly uncertain and ambiguous political environments and could truly have a significant impact on school reform as manifest in the learning outcomes of children. After interviewing more than a hundred superintendents, academics, and principals we designed the leadership program. The program would focus on how to facilitate adaptive problem solving; how to make effective interventions into school systems and the community; the design of the strategies needed to muster support and protection from the political system; how to establish a profound sense of purpose and mission that can keep people focused on and committed to what really matters—namely the education of children, and the skills and techniques of being an outstanding agent of change who operates with wisdom, prowess, and fortitude

The Central Symbiosis of Molecular Biology: Molecules in Mutualism.

As illustrated by the mitochondrion and the eukaryotic cell, little in biology makes sense except in light of mutualism. Mutualisms are persistent, intimate, and reciprocal exchanges; an organism proficient in obtaining certain benefits confers those on a partner, which reciprocates by conferring different benefits. Mutualisms (i) increase fitness, (ii) inspire robustness, (iii) are resilient and resistant to change, (iv) sponsor co-evolution, (v) foster innovation, and (vi) involve partners that are distantly related with contrasting yet complementary proficiencies. Previous to this work, mutualisms were understood to operate on levels of cells, organisms, ecosystems, and even societies and economies. Here, the concepts of mutualism are extended to molecules and are seen to apply to the relationship between RNA and protein. Polynucleotide and polypeptide are Molecules in Mutualism. RNA synthesizes protein in the ribosome and protein synthesizes RNA in polymerases. RNA and protein are codependent, and trade proficiencies. Protein has proficiency in folding into complex three-dimensional states, contributing enzymes, fibers, adhesives, pumps, pores, switches, and receptors. RNA has proficiency in direct molecular recognition, achieved by complementary base pairing interactions, which allow it to maintain, record, and transduce information. The large phylogenetic distance that characterizes partnerships in organismal mutualism has close analogy with large distance in chemical space between RNA and protein. The RNA backbone is anionic and self-repulsive and cannot form hydrophobic structural cores. The protein backbone is neutral and cohesive and commonly forms hydrophobic cores. Molecules in Mutualism extends beyond RNA and protein. A cell is a consortium of molecules in which nucleic acids, proteins, polysaccharides, phospholipids, and other molecules form a mutualism consortium that drives metabolism and replication. Analogies are found in systems such as stromatolites, which are large consortia of symbiotic organisms. It seems reasonable to suggest that 'polymers in mutualism relationships' is a useful and predictive definition of life

Visualization and Analysis Tools for Ultrascale Climate Data

Increasingly large climate model simulations are enhancing our understanding of the processes and causes of anthropogenic climate change, thanks to very large public investments in high-performance computing at national and international institutions. Various climate models implement mathematical approximations of nature in different ways, which are often based on differing computational grids. These complex, parallelized coupled system codes combine numerous complex submodels (ocean, atmosphere, land, biosphere, sea ice, land ice, etc.) that represent components of the larger complex climate system

Better Tools to Build Better Climate Models

A Department of Energy collaboration aims to make climate model development faster and more efficient by creating a prototype of a system for testing model components

Biological implications of chemical and radiological warfare

Thesis (M.A.)--Boston UniversityThis thesis is a major review of the acute biological effects of chemical and radiological weapons. These agents of modern warfare have a broader spectrum of biological effects than the weapons of past wars and also present more profound biological sequelae. In order to cope with the threat that these weapons pose, it is necessary to be familiar with the types of agents which might be used, the symptomatology, the modes of physiological effect, and the basic mechanisms of cellular action. The acute radiation syndrome is covered in detail along with hypotheses of the cellular action of ionizing radiation and a review of methods for protection against radiation [TRUNCATED

An investigation of the deformation textures of titanium

With the increase in production of titanium in recent years has come a great interest in the mechanical properties and in the possible uses of this metal. Due to the affinity of titanium for oxygen, nitrogen, carbon, and hydrogen, and the market effect of these elements on the mechanical properties, much of the work previously reported is unreliable. As purer commercial grades of titanium and high purity iodide titanium have become available for examination, research has been undertaken to correct and expand the knowledge of the properties of titanium. Although the uses of titanium are limited at the present time, a considerable amount of time and money is being spent to thoroughly exploit its possibilities and it is expected that titanium will soon hold an established position as one of the more important light metals. A. The problem. Statement of the problem. This study was undertaken (1) to determine the textures developed in titanium during cold rolling, (2) to determine why the observed textures of titanium differ from those of other hexagonal metals, and (3) to develop a satisfactory explanation of the deformation textures of titanium --Introduction, pages 1-2

An examination of DMO network identity using Exponential Random Graph Models

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