Fatigue testing a plurality of test specimens and method

Described is a fatigue testing apparatus for simultaneously subjecting a plurality of material test specimens to cyclical tension loading to determine the fatigue strength of the material. The fatigue testing apparatus includes a pulling head having cylinders defined therein which carry reciprocating pistons. The reciprocation of the pistons is determined by cyclical supplies of pressurized fluid to the cylinders. Piston rods extend from the pistons through the pulling head and are attachable to one end of the test specimens, the other end of the test specimens being attachable to a fixed base, causing test specimens attached between the piston rods and the base to be subjected to cyclical tension loading. Because all the cylinders share a common pressurized fluid supply, the breaking of a test specimen does not substantially affect the pressure of the fluid supplied to the other cylinders nor the tension applied to the other test specimens

Atomic radius and charge parameter uncertainty in biomolecular solvation energy calculations

Atomic radii and charges are two major parameters used in implicit solvent electrostatics and energy calculations. The optimization problem for charges and radii is under-determined, leading to uncertainty in the values of these parameters and in the results of solvation energy calculations using these parameters. This paper presents a new method for quantifying this uncertainty in implicit solvation calculations of small molecules using surrogate models based on generalized polynomial chaos (gPC) expansions. There are relatively few atom types used to specify radii parameters in implicit solvation calculations; therefore, surrogate models for these low-dimensional spaces could be constructed using least-squares fitting. However, there are many more types of atomic charges; therefore, construction of surrogate models for the charge parameter space requires compressed sensing combined with an iterative rotation method to enhance problem sparsity. We demonstrate the application of the method by presenting results for the uncertainties in small molecule solvation energies based on these approaches. The method presented in this paper is a promising approach for efficiently quantifying uncertainty in a wide range of force field parameterization problems, including those beyond continuum solvation calculations.The intent of this study is to provide a way for developers of implicit solvent model parameter sets to understand the sensitivity of their target properties (solvation energy) on underlying choices for solute radius and charge parameters

B840: Firm Formation, Firm Failure, and Competitiveness: An Overview of Maine\u27s Entrepreneurial Economy

The purpose of this paper is to establish a basic understanding of Maine\u27s entrepreneurial economy. The competitiveness of Maine\u27s small businesses, reflected in rates of firm formation and firm failure, is important to future economic growth and policy development. Previous research has pointed to the high proportion of small businesses operating in Maine, but questions concerning their entrepreneurial dynamism remain unanswered. Developing a useful policy response for future economic growth dictates that the following questions be fully explored: (1) What is the current state of Maine\u27s entrepreneurial base and how does this base compare with other states in the New England region? (2) How is this base changing with respect to firm formation and business failures, and are there sectors of emerging strength and competitiveness? (3) Are there rural/urban differences that form a potential basis for policy differentiation? (4) What are the crucial elements of entrepreneurship and associated policy development for economic growth in Maine?https://digitalcommons.library.umaine.edu/aes_bulletin/1018/thumbnail.jp

B804: The Growth and Change of High Technology Industries in the State of Maine: Implications for State and Local Development Policy

To shed light on Maine’s high-tech industries, employment and production data were gathered for 11O firms including 20 three-digit SIC (Standard Industrial Classification) categories. The time periods covered were 1970, 1976, and 1981. This data base was provided by the Bureau of Employment Security and the Bureau of Labor Standards of the Maine Department of Labor. The research was guided by the following questions: How are firms distributed among specific high technology industries and has this distribution changed over time? What is the geographic distribution of high technology firms within the state and how is this distribution changing? How dynamic have Maine\u27s high technology industries been with respect to plant openings, closings, and acquisitions? How is employment generation distributed by size, age, SIC, and type of firm? Does Maine show a potential comparative advantage for specific high technology SIC\u27s? and What implications can be drawn from the Maine data for rural communities seeking high technology development?https://digitalcommons.library.umaine.edu/aes_bulletin/1057/thumbnail.jp

B845: The Cost of Doing Business and Economic Performance in Maine: A Regional Comparison

This study attempts to address the need for better understanding of those business climate factors that have a direct and measurable impact upon statewide economic performance by comparing several key costs faced by businesses in each of the New England states, and by examining how those costs relate to general economic conditions in each state.https://digitalcommons.library.umaine.edu/aes_bulletin/1007/thumbnail.jp

Humanitarianism's Contested Culture in War Zones

Humanitarians are no longer simply seen as selfless angels. Their motivations and mastery, their principles and products are questioned from within and from without. Understanding the ongoing transformations in contemporary humanitarianism requires examining the nature and evolution of humanitarian culture away from an agreed culture of cooperation to a contested one of competition. The latter reflects militarization, politicization, and marketization. What is required is a learning culture for practitioners and a consequentialist ethics more oriented to responsible reflection than rapid reaction

Short-term studies underestimate 30-generation changes in a butterfly metapopulation

Most studies of rare and endangered species are based on work carried out within one generation, or over one to a few generations of the study organism. We report the results of a study that spans 30 generations (years) of the entire natural range of a butterfly race that is endemic to 35 km2 of north Wales, UK. Short-term studies (surveys in single years and dynamics over 4 years) of this system led to the prediction that the regional distribution would be quite stable, and that colonization and extinction dynamics would be relatively unimportant. However, a longer-term study revealed unexpectedly high levels of population turnover (local extinction and colonization), affecting 18 out of the 20 patches that were occupied at any time during the period. Modelling the system (using the 'incidence function model' (IFM) for metapopulations) also showed higher levels of colonization and extinction with increasing duration of the study. The longer-term dynamics observed in this system can be compared, at a metapopulation level, with the increased levels of variation observed with increasing time that have been observed in single populations. Long-term changes may arise from local changes in the environment that make individual patches more or less suitable for the butterfly, or from unusual colonization or extinction events that take metapopulations into alternative states. One implication is that metapopulation and population viability analyses based on studies that cover only a few animal or plant generations may underestimate extinction threats

Camptothecin Intermediates and Prodrugs and Methods of Preparation Thereof

The present invention relates to novel intermediates and prodrugs of camptothecin and related analogs

Highly Lipophilic Camptothecin Intermediates and Prodrugs and Methods of Preparation Thereof

The present invention relates to novel, highly lipophilic silatecan intermediates and prodrugs of DB-67 and other silatecans