A History and Evaluation of a Small District’s Elementary School Camping Program

The purposes of this study were (1) to enable the writer to gain a knowledge of school camping programs; (2) to develop criteria for the establishment of successful school camping programs; and (3) to outline a definite program of procedures for the establishment of a school camping program for seventh grade pupils

Analysis and simulation of small scale microwave interferometer experiments on non-ideal explosives

Small scale experiments for non-ideal and homemade explosives (HMEs) were investigated, analyzed, and subsequently modeled in an attempt to develop more predictive capabilities for the threat assessment of improvised explosive devices (IEDs), as well as to provide new analysis capabilities for other investigators in the field. Non-ideal explosives and HMEs are challenging to characterize because of the nearly limitless parameter space (e.g. sample composition, density, particle morphology, etc.) which gives rise to a broad range of explosive sensitivity and performance. Large scale tests, such as rate stick and gap tests, are not feasible for characterizing every HME of interest due to limitations in time and cost. These small scale experiments utilize a 35 GHz microwave interferometer to measure the instantaneous shock and failing detonation wave velocities in explosives. Only those explosives which are transparent to the microwave radiation are evaluated, including ammonium nitrate plus fuel oil (ANFO). It is shown here for the first time that the small scale measurements may be related to large scale sensitivity and performance for a large enough sample size and level of confinement. Specifically, four different experimental configurations were explored that require only 1-5 g of material. By varying the charge diameter, as well as the thickness and sound speed of the confining material, the failure rate and shock front curvature of an overdriven failing detonation may be tailored. The detailed experimental data is also highly repeatable, provided that the initial sample density is uniform and consistent from test to test. Results from the MI data also reveal the existence of an inflexion point in velocity, which is thought to be related to the measurements obtained from larger rate sticks. The different MI experiments were subsequently modeled in 2d as well as 3d using the shock physics hydrocode CTH. An ignition and growth reactive burn (IGRB) model was developed for non-ideal explosives, and shown to be relevant to capturing the behavior of some of the overdriven failing detonation waves. Many simplifying assumptions were made, so that the MI data might possibly be used for model calibration and validation. It was determined that an intermediate level of confinement utilizing low sound speed polyvinyl chloride (PVC) is most relevant for fitting the IGRB model constants, which were then used to predict the other MI experiments with partial success. Overall, the CTH simulations provide much more information than what is available from the MI measurements alone. These simulations were used to investigate pressure waves in the explosive and confiner materials, and to show that the reactive waves are likely transitioning from supersonic to subsonic deflagration, where thermal effects, compaction behavior, and material strength are important. Consequently, these simulations are not able to match the weaker confinement and smaller diameter experiments over the full duration of the tests. The calibrated IGRB model was then used to make several predictions for shock sensitivity, changes to the initial density, and other large scale tests. Future work is suggested to validate these predictions and to improve the model development. Overall, the high level of integration between experimental and modeling efforts shown in this work is critical to better understand HMEs and to design new small scale experiments

The Morgan Group of Bestiaries: An Analysis

Trying to figure out where and when a medieval manuscript was made is one of the most contentious topics in book scholarship. Instead of limiting scholarship to textual contents, new work looks at manuscripts, including bestiaries, with a multifaceted and interdisciplinary approach, which leads to exciting new ideas. Bestiaries were among the most popular texts in medieval England and have consistently been viewed as only their textual contents. Starting in the 1980’s, bestiary scholarship expanded beyond text, but a textually and iconographically similar group of bestiaries had not yet received the same holistic treatment. The Morgan Group is the British Library Royal C XIX, the Worksop Bestiary (Pierpont Morgan Library, M.81), the Northumberland Bestiary (J. Getty Museum and Library, MS.100) and the St. Petersburg Bestiary (National Library of Russia, Q.v.V.1). There has been no in-depth investigation of the group together and with image analysis privileged over textual recension.I will look at the Morgan Group as a whole, then, after finding the differences and similarities, I will add to the conversation about dating and locating their production, I will discuss the textual traditions for context, and finally look at the manuscripts through analysis of individual style, composition, color, and mise-en-page. This research will provide evidence for why the bestiaries were so popular and how they were utilized in medieval English society

Experimental Evidence for a Metallohydrolase Mechanism in Which the Nucleophile Is Not Delivered by a Metal Ion: EPR Spectrokinetic and Structural Studies of Aminopeptidase from \u3cem\u3eVibrio proteolyticus\u3c/em\u3e

Metallohydrolases catalyse some of the most important reactions in biology and are targets for numerous chemotherapeutic agents designed to combat bacterial infectivity, antibiotic resistance, HIV infectivity, tumour growth, angiogenesis and immune disorders. Rational design of inhibitors of these enzymes with chemotherapeutic potential relies on detailed knowledge of the catalytic mechanism. The roles of the catalytic transition ions in these enzymes have long been assumed to include the activation and delivery of a nucleophilic hydroxy moiety. In the present study, catalytic intermediates in the hydrolysis of L-leucyl-L-leucyl-L-leucine by Vibrio proteolyticus aminopeptidase were characterized in spectrokinetic and structural studies. Rapid-freeze-quench EPR studies of reaction products of L-leucyl-L-leucyl-L-leucine and Co(II)-substituted aminopeptidase, and comparison of the EPR data with those from structurally characterized complexes of aminopeptidase with inhibitors, indicated the formation of a catalytically competent post-Michaelis pre-transition state intermediate with a structure analogous to that of the inhibited complex with bestatin. The X-ray crystal structure of an aminopeptidase–L-leucyl-L-leucyl-L-leucine complex was also analogous to that of the bestatin complex. In these structures, no water/hydroxy group was observed bound to the essential metal ion. However, a water/hydroxy group was clearly identified that was bound to the metal-ligating oxygen atom of Glu152. This water/hydroxy group is proposed as a candidate for the active nucleophile in a novel metallohydrolase mechanism that shares features of the catalytic mechanisms of aspartic proteases and of B2 metallo-b-lactamases. Preliminary studies on site-directed variants are consistent with the proposal. Other features of the structure suggest roles for the dinuclear centre in geometrically and electrophilically activating the substrate

Moving Difference (MDIFF) Non-adiabatic Rapid Sweep (NARS) EPR of Copper(II)

Non-adiabatic rapid sweep (NARS) EPR spectroscopy has been introduced for application to nitroxide-labeled biological samples (Kittell et al., 2011). Displays are pure absorption, and are built up by acquiring data in spectral segments that are concatenated. In this paper we extend the method to frozen solutions of copper-imidazole, a square planar copper complex with four in-plane nitrogen ligands. Pure absorption spectra are created from concatenation of 170 5-gauss segments spanning 850 G at 1.9 GHz. These spectra, however, are not directly useful since nitrogen superhyperfine couplings are barely visible. Application of the moving difference (MDIFF) algorithm to the digitized NARS pure absorption spectrum is used to produce spectra that are analogous to the first harmonic EPR. The signal intensity is about four times higher than when using conventional 100 kHz field modulation, depending on line shape. MDIFF not only filters the spectrum, but also the noise, resulting in further improvement of the SNR for the same signal acquisition time. The MDIFF amplitude can be optimized retrospectively, different spectral regions can be examined at different amplitudes, and an amplitude can be used that is substantially greater than the upper limit of the field modulation amplitude of a conventional EPR spectrometer, which improves the signal-to-noise ratio of broad lines

Formal Education of the Hospital Department Supervisors and the Need for an Undergraduate Degree Program in Health Services Management

No Abstract Avaliable