This research is an exploratory study of role conflict and role ambiguity and their relationships to effectiveness in the substitute teaching services. In many public school systems, large numbers of substitute teachers are assigned to a classroom on a daily basis when the regular teacher is absent. The assignment is usually done through a central administrative office. Substitutes are assigned with very short notice; and since their assignment is based on availability, they may be asked to teach a subject outside their certified field. In addition, the lesson plans left for the substitutes by regular teachers may be incomplete or too complex. These situations prevent the school district's goal of instructional continuity from materializing. Thus, some studies have shown substitute teachers to be ineffective in the classroom because they were unable to effect the continuity principle. These studies, however, do not show the relationship between role clarity and effectiveness. This research uses role theory as a framework in which to examine the performance of substitute teachers. The literature suggests that role conflict/ambiguity may be related to certain personal and behavioral outcomes. Conceptual models have also shown other indirect factors that may influence the final performance outcome. The primary question of this research was what needs to be done to improve the substitute teaching services. Specific questions include: (1) To what extent, if any, is there an inter-sender role conflict? Do regular teachers and administrators have a common view regarding the role of the substitute teacher? (2) According to administrators, regular teachers, and substitute teachers, is there role ambiguity regarding the work of substitute teachers? (3) According to administrators, regular teachers and substitute teachers, how effective are substitute teachers at specified tasks? Hypotheses were also tested to determine the relationship between role ambiguity and effectiveness, and the relationship between the socio-economic status of the work-place and the perceived performance. Data on the perceived role, and effectiveness of substitute teachers were collected by random sampling from three groups of educators in two socio-economic areas in the city. ANOVA was used to compare role ambiguity and role conflict. A constructed effectiveness scale gave a reliability coefficient alpha of .82. Pearson correlations were also used to test hypotheses. The results show a negative relationship between role ambiguity and substitute teacher effectiveness. However, there was no role conflict among the three groups of educators tested, nor did the socio-econanic status of the work-place make any difference in their perception of the substitute teaching services.

In-situ EBSD on profuse {10ˉ12} twinning in magnesium revealed that the twinning stress for nucleation is not totally rate-insensitive but highly dependent on grain boundary misorientation ranging between 10° and 15°. A new regime in the theta-strain curve; Regime-D, before Regime II, was identified for axisymmetric textures and corresponded to mitigation of twin propagation which was markedly rate-sensitive, such when the strain-rate fell below 10-5/s, twin propagation, but not twin nucleation, was completely halted and this fact substantiates the predominant effect of transmutation on Regime II hardening over that of Hall and Petch by twin segmentation. This technique revealed that twin nucleation dominates twin growth rate over twin propagation in grains undergoing multi-variant twinning under high-Schmid factors. Pseudo-elasticity in Mg was revealed to originate from an unusual detwinning phenomenon of residual twins. This effect was attributed to incomplete accommodation slip necessary for the shape change by twin to take place.

A model of the chemostat involving two populations of microorganisms competing for two perfectly substitutable, growth limiting nutrients is developed. To describe nutrient uptake, a general class of functions is used which allows for the effects that the consumption of one resource may have on the consumption of the other. It includes as a special case the model studied by Waltman, Hubbell and HSu [21] in which they generalize Michaelis-Menten functional response for a single resource to two perfectly substitutable resources. It also generalizes the model studied by Leon and Tumpson [12] where the consumption of each resource is unaffected by the consumption of the other. Analytical methods are used to obtain information about the qualitative behaviour of the model. Interesting similarities are found between both the local and global behaviour in this model and in the model for perfectly complementary resources. / Thesis / Master of Science (MS)

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Design and characterization of tissue engineered substitutes rely on robust monitoring techniques that provide information regarding viability and function when exposed to various environmental conditions. In vitro studies permit the direct monitoring of cellular and construct changes because these substitutes remain accessible. However, upon in vivo implantation, changes in cell viability and function are often detected using indirect or invasive methods that make assessing temporal changes challenging. . Thus, the development of non-invasive monitoring modalities may facilitate improved tissue substitute design and, ultimately, clinical outcome. The overall objective of this thesis was to establish a method to monitor and track cells and the cellular environment within a tissue engineered substitute in vitro and in vivo. This was accomplished via 31P NMR spectroscopy and through the incorporation of perfluorocarbon (PFC) emulsions for the monitoring of DO concentration by 19F NMR spectroscopy. The first aim of this thesis was to develop a method that tracked the state of cells and of the cellular environment within alginate constructs during perfusion studies in which the perfusing medium DO concentrations were changed over time or cells were exposed to a cytotoxic antibiotic. Due to challenges in acquiring DO concentration gradient information within beads, a second aim was to develop a mathematical model that would calculate gradients from experimentally acquired volume averaged DO concentrations; thus, significantly enhancing the robustness of tracking the alginate beads. Lastly, since the PFC emulsions used in the study may affect cell viability and function, a third aim was to characterize, experimentally and via modeling, the effect of several PFC emulsion concentrations on the encapsulated and #946;TC-tet cells.

A total of 259 educators participated in a survey to assess whether substitute teachers in Southern Alberta enjoy the same professional regard and the same wages, benefits, and professional development opportunites as regular classroom teachers. The finding indicated that: substitute teachers are professional in that they are certificated teachers with Education Degrees; substitute teachers are not in accordance with other educators in their assessmentd of the reality of equal professional status of substitute teachers in matters of professional regard; principals and teachers do not agree that substitute teachers should be given equal wages, benefits, and paid professional development opportunities; the defintion of equal professional status as it pertains to substitute teachers needs to be redefined; and substitute teacher must understand their professional responsibilites so they can take control of their own professionalism. Within the framework of the sociology of professionalism the results of the study help to explain why stubstitute teachers should be taking control of the work they do in order to define their professional role. Workshops for educators on substitue issues and concerns will help alleviate the contradiction of the concept of the professional status of substitute teachers. Substitute teacher involvement in their professional associations may ease the conflict between substitutes and other educators in matters of professionalism and economic parity. A follow-up study on student perception of substitute authority in the classroom is needed. / ix, 231 leaves ; 28 cm.

Thesis (M.A.)--Bristol University, 2002. / Title from PDF title screen. Also available to download as a zipped file in Microsoft Word format.

Two thallium scorpionate complexes: dihydrobis (3-phenyl-4-cyanopyrazolyl) boratothallium(I) (TlBp Ph,4CN), C 20H 14BN 6Tl and dihydrobis(3-tert-butyl-4-cyanopyrazolyl) boratothallium(I) (TlBp t-Bu,4CN), C 16H 22BN 6Tl have been prepared and characterized by X-ray diffraction. Both compounds crystallize in monoclinic space groups, TlBp Ph,4CN in P2 1/n with a = 4.2039(3) Å, b = 26.2211(17) Å, c = 16.611(1) Å, β = 90.199(3)°, and TlBp t-Bu,4CN in P2 1/c with a = 13.8578(5) Å, b = 9.6741(4) Å, c = 14.2790(5) Å, β 95.141(2)°. The two complexes show similar structures with elongated metal-ligand bonds and intermolecular interactions between the metal ion and cyano substituents, allowing the potential construction of cyanobridged coordination polymers.

Effective substitute teachers are needed in classrooms across the United States; however, little attention is given to the policies and practices that school districts use to recruit, train, and evaluate them. The challenge of finding quality substitute teachers, despite the absence of definitive policies and practices to guide them, continues to be a problem nationwide. The purpose of this study was to identify, using a three-round Delphi technique (Linstone & Turoff, 1975), policies and practices school districts could use to recruit, train, and evaluate substitute teachers. Data were gathered from a panel of experts who represent a variety of independent thinking on school district policies and practices for recruiting, training, and evaluating substitute teachers. The Delphi had three rounds of questions. During each round the panel members did not meet as a group (Tam & Mills, 2006). Data were collected in 2008-2009. The nationwide panel of experts included writers and researchers, human resources directors, developers of programs for training substitute teachers, and participants at a national conference who managed programs for substitute teachers. The panel represented all six regions of the American Association of School Personnel Administrators, even though all were not active members of the association. The findings provided information about substitute teachers on policies and practices to assist school districts in providing high-quality substitute teachers in classrooms when the regular teachers are absent and intended to affect policies and practices regarding the manner in which substitute teachers are recruited, trained, and evaluated. By the end of the third round of the Delphi, the panel identified 27 policies and 51 practices school boards could enact and employ, respectively, to recruit, train, and evaluate substitute teachers. The panelists recommended policies on compensation, district support, strategies and processes, and performance expectations. They recommended specific performance criteria and evaluation practices, content and methods of training, and procedures for recruitment of high-quality substitutes. An instrument for evaluating the policies and practices covering substitute teachers is a product of the study. / Ed. D.