The influence of cartridge diameter on the effectiveness of dynamite

For many years the manufacturers of explosives have attempted to show the advantages of using dynamite of a cartridge diameter of at least 1-1/8 inches. Tests by the manufacturers and by the United States Bureau of Mines hare definitely shown that the dynamites prepared in larger diameter cartridges have several advantages: They are more sensitive to detonation; they detonate at a higher velocity; they are resistant to water; they are safer to use; and they are more stable than dynamites made in smaller diameter cartridges. In spite of these advantages listed, several large consumers still insist on smaller diameter cartridges. Dynamite is sold by weight and the cost to the consumer for a box of 50 pounds is the same regardless of the cartridge size. The manufacturing cost, however, increases with the smaller diameter cartridge because it takes more cartridges to fill a 50-pound box. The study described in this thesis was suggested to the Mining Department of Missouri School of Mines and Metallurgy by officials of the Explosives Division of E. I. du Pont de Nemours & Company, of Wilmington, Delaware. With their cooperation an attempt has been made to determine the effectiveness of different sized cartridges of dynamite when used under actual mining conditions --Introduction, page 1

In Vitro Simulation of Microgravity Induced Muscle Loss Successfully Increases Expression of Key In Vivo Atrophy Markers

Muscle loss from lack of activity is a serious issue for immobilized patients on Earth and in human spaceflight, where the low gravity environment prevents normal muscle activity. Simulating muscle loss in cultured cells is an important step in understanding how this condition occurs. This work evaluates different means of simulating muscle loss and selects the one that most closely mimics the cellular responses seen in animals and humans. To simulate the microgravity environment of spaceflight, mouse skeletal muscle cells were grown in a rotary cell culture system (RCCS). Growing the cells within a natural gelled substrate was compared against growing them on the surface of small plastic beads. Changes after culture under simulated microgravity were characterized by assessing proteins and genes known to change during muscle loss. The structure of the cells was also evaluated by microscopy. The mouse skeletal muscle cells grown on plastic beads in the RCCS had significant changes in multiple key genes associated with muscle loss and demonstrated physical characteristics expected of mature tissue in live animals. This model is a valuable platform for exploring muscle loss mechanisms and testing new drugs

Muscle Atrophy Marker Expression Differs between Rotary Cell Culture System and Animal Studies

Muscular atrophy, defined as the loss of muscle tissue, is a serious issue for immobilized patients on Earth and for humans during spaceflight, where microgravity prevents normal muscle loading. In vitro modeling is an important step in understanding atrophy mechanisms and testing countermeasures before animal trials. The most ideal environment for modeling must be empirically determined to best mimic known responses in vivo. To simulate microgravity conditions, murine C2C12 myoblasts were cultured in a rotary cell culture system (RCCS). Alginate encapsulation was compared against polystyrene microcarrier beads as a substrate for culturing these adherent muscle cells. Changes after culture under simulated microgravity were characterized by assessing mRNA expression of MuRF1, MAFbx, Caspase 3, Akt2, mTOR, Ankrd1, and Foxo3. Protein concentration of myosin heavy chain 4 (Myh4) was used as a differentiation marker. Cell morphology and substrate structure were evaluated with brightfield and fluorescent imaging. Differentiated C2C12 cells encapsulated in alginate had a significant increase in MuRF1 only following simulated microgravity culture and were morphologically dissimilar to normal cultured muscle tissue. On the other hand, C2C12 cells cultured on polystyrene microcarriers had significantly increased expression of MuRF1, Caspase 3, and Foxo3 and easily identifiable multinucleated myotubes. The extent of differentiation was higher in simulated microgravity and protein synthesis more active with increased Myh4, Akt2, and mTOR. The in vitro microcarrier model described herein significantly increases expression of several of the same atrophy markers as in vivo models. However, unlike animal models, MAFbx and Ankrd1 were not significantly increased and the fold change in MuRF1 and Foxo3 was lower than expected. Using a standard commercially available RCCS, the substrates and culture methods described only partially model changes in mRNAs associated with atrophy in vivo

Diagnostic assessment of reading and listening in a second or foreign language:elaborating on diagnostic principles

Alderson, Brunfaut and Harding (2014) recently investigated how diagnosis is practised across a range of professions in order to develop a tentative framework for a theory of diagnosis in second or foreign language (SFL) assessment. In articulating this framework, a set of five broad principles were proposed, encompassing the entire enterprise of diagnostic assessment. However, there remain questions about how best to implement these principles in practice, particularly in identifying learners’ strengths and weaknesses in the less well-documented areas of SFL reading and listening. In this paper, we elaborate on the set of principles by first outlining the stages of a diagnostic process built on these principles, and then discussing the implications of this process for the diagnostic assessment of reading and listening. In doing so, we will not only elaborate on the theory of diagnosis with respect to its application in the assessment of these skills, but also discuss the ways in which each construct might be defined and operationalized for diagnostic purposes

Bridging assessment and learning:a view from second and foreign language assessment

This paper considers issues around the relationship between assessment and learning, as put forward by Baird, Andrich, Hopfenbeck and Stobart (2017), from the perspective of the field of second and foreign language assessment. In our response, we describe shared observations on the nature of research and practice in general educational assessment and in language assessment (including with respect to linking assessment with theories of learning, managing impact, and enhancing assessment literacy). At the same time, we also identify areas where language assessment seems to diverge from current research and practice in general educational assessment (for example in the areas of assessment purposes, construct definitions, and validation theory and practice). As a consequence, we believe that close monitoring of advances in both fields is likely to be mutually beneficial

Bridging assessment and learning:a view from second and foreign language assessment

This paper considers issues around the relationship between assessment and learning, as put forward by Baird, Andrich, Hopfenbeck and Stobart (2017), from the perspective of the field of second and foreign language assessment. In our response, we describe shared observations on the nature of research and practice in general educational assessment and in language assessment (including with respect to linking assessment with theories of learning, managing impact, and enhancing assessment literacy). At the same time, we also identify areas where language assessment seems to diverge from current research and practice in general educational assessment (for example in the areas of assessment purposes, construct definitions, and validation theory and practice). As a consequence, we believe that close monitoring of advances in both fields is likely to be mutually beneficial

Exploring United States and South Korean National Cultures: Improving Alliance Partnerships

Understanding the effects of national culture differences on cooperation and performance is a problem facing the United States and South Korean Air Component Command Headquarters. Little is known about the dynamics of national cultural differences within the headquarters, and as a result, little attention is given to educating members on how to manage multicultural relationships. Guided by Hofstede\u27s cultural dimension theory and Schein\u27s model of organizational culture, the purpose of this quantitative quasi-experimental study was to understand the factors influencing national cultural differences among the United States and South Korean staff officers (N =178) assigned to the Air Component Command Headquarters, Republic of South Korea. Primary data were collected using the 2013 Values Survey Module. The following 6 dependent variables were examined: power distance, individualism, indulgence, masculinity, uncertainty avoidance, and long-term orientation. These data were analyzed via bivariate correlation, independent-sample t tests, and one-way analysis of variance. Analysis of variance and t-test findings indicated that an increase in cross-cultural experience (military exchanges, foreign language proficiency, and years lived abroad) influenced national cultural scores. Additionally, to a moderate extent, bivariate correlation analysis showed that national cultures could also be affected (positively and negatively) by differences in participant education levels, military seniority and time served, years lived abroad, military exchanges, and foreign language experience. Implications for positive social change include increasing national cultural awareness among Air Component Command members as a method for improving collaboration and military readiness

Characterization of the Effects of Radiation on Skeletal and Smooth Muscle Cells

Muscular atrophy is a serious issue for extended spaceflight. Understanding and preventing the role of ionizing radiation in skeletal muscle loss would preserve the strength and endurance of astronauts and enable longer duration space travel and exploration. Irradiation was performed in the USU material physics group\u27s Space Suvivability Test Chamber. C2C12 and CRL-1999 cells were exposed to dosages ranging from 0.5 - 36.8 Gy. Cell viability and growth rate were measured immediately following irradiation