The construction and validation of a test of the ability of junior-senior high school pupils to understand word meaning through the use of context

Thesis (Ed.D.)--Boston Universit

Comparison of Antimicrobials and Delivery Methods on the Inactivation of Listeria monocytogenes on Apples

Introduction: Due to multi-state outbreaks of listeriosis on apples in 2015, 2017, and 2019, Listeria Monocytogenes (L. monocytogenes) has been deemed an emerging, under researched pathogen by the USDA-NIFA. Therefore, this study evaluated the efficacy of SaniDate 5.0®’s (SD) ability to inactivate L. Monocytogenes on apples when delivered through electrostatic sprayer (ES), garden sprayer (GS), and dip methods. Methods: Organic apples were dip-inoculated with L. monocytogenes for 5 min and then dried for 10 min. Once dried, the inoculated apples were untreated (control), sprayed with water only, or treated with SD, 0.0064, 0.1, 0.25 and 0.50% for 20 s via GS, ES, or dip. Then the apples were drained (2 min) and placed in a sterile sample bag with 100 ml TSB and shaken for 30 sec. Samples were later 10 or 100-fold serially diluted in 0.1% BPW and spread plated on MOX agar plates, followed by incubation for 48 hrs at 37°C and enumeration. The Mixed Model Procedure of SAS (p=0.05) was used to analyze the reduction of L. monocytogenes on cultivars (2 replicates/6 samples/replicate) under different delivery methods, concentrations, and interactions. Results: Results indicated dip was the most effective antimicrobial delivery method compared to GS and ES and reductions of L. monocytogenes were greatest (P \u3c 0.05) when apples were treated with 0.50% SD. Significance: Results suggested that applying 0.5%SD through dipping methods are effective at inactivating pathogens on apples, thus reducing the risk for future listeriosis outbreaks

Magnetic friction in Ising spin systems

A new contribution to friction is predicted to occur in systems with magnetic correlations: Tangential relative motion of two Ising spin systems pumps energy into the magnetic degrees of freedom. This leads to a friction force proportional to the area of contact. The velocity and temperature dependence of this force are investigated. Magnetic friction is strongest near the critical temperature, below which the spin systems order spontaneously. Antiferromagnetic coupling leads to stronger friction than ferromagnetic coupling with the same exchange constant. The basic dissipation mechanism is explained. If the coupling of the spin system to the heat bath is weak, a surprising effect is observed in the ordered phase: The relative motion acts like a heat pump cooling the spins in the vicinity of the friction surface.Comment: 4 pages, 4 figure

Prospect for room temperature tunneling anisotropic magnetoresistance effect: density of states anisotropies in CoPt systems

Tunneling anisotropic magnetoresistance (TAMR) effect, discovered recently in (Ga,Mn)As ferromagnetic semiconductors, arises from spin-orbit coupling and reflects the dependence of the tunneling density of states in a ferromagnetic layer on orientation of the magnetic moment. Based on ab initio relativistic calculations of the anisotropy in the density of states we predict sizable TAMR effects in room-temperature metallic ferromagnets. This opens prospect for new spintronic devices with a simpler geometry as these do not require antiferromagnetically coupled contacts on either side of the tunnel junction. We focus on several model systems ranging from simple hcp-Co to more complex ferromagnetic structures with enhanced spin-orbit coupling, namely bulk and thin film L1$_0$-CoPt ordered alloys and a monatomic-Co chain at a Pt surface step edge. Reliability of the predicted density of states anisotropies is confirmed by comparing quantitatively our ab initio results for the magnetocrystalline anisotropies in these systems with experimental data.Comment: 4 pages, 2 figure

Agency Directors And Network Centrality: An Examination Of Resource Dependencies

A basic tenet of resource dependence theory is organizations must obtain resources from their environments in order to survive (Pfeffer and Salancik, 1978). Ac- cording to the theory, there are several strategic factors that affect how organizations manage inter- organizational resource exchanges. These strategic factors include (1) interlocking of board of director members, (2) joint programs or joint ventures, (3) organization size, and (4) top administrator contacts with other organizations (Pfeffer and Salancik 1978: 143-69). Organizations engage in these activities to reduce uncertainty and to develop favorable linkages in interorganizational network

Electronic structure and effects of dynamical electron correlation in ferromagnetic bcc-Fe, fcc-Ni and antiferromagnetic NiO

LDA+DMFT method in the framework of the iterative perturbation theory (IPT) with full LDA Hamiltonian without mapping onto the effective Wannier orbitals. We then apply this LDA+DMFT method to ferromagnetic bcc-Fe and fcc-Ni as a test of transition metal, and to antiferromagnetic NiO as an example of transition metal oxide. In Fe and Ni, the width of occupied 3d bands is narrower than those in LDA and Ni 6eV satellite appears. In NiO, the resultant electronic structure is of charge-transfer insulator type and the band gap is 4.3eV. These results are in good agreement with the experimental XPS. The configuration mixing and dynamical correlation effects play a crucial role in these results