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The Magellanic Stream (MS) is a massive and extended tail of multi-phase gas stripped out of the Magellanic Clouds and interacting with the Galactic halo. In this first paper of an ongoing program to study the Stream in absorption, we present a chemical abundance analysis based on HST/COS and VLT/UVES spectra of four AGN (RBS 144, NGC 7714, PHL 2525, and HE 0056-3622) lying behind the MS. Two of these sightlines yield good MS metallicity measurements: toward RBS 144 we measure a low MS metallicity of [S/H]=[S II/H I]=-1.13+/-0.16 while toward NGC 7714 we measure [O/H]=[O I/H I]=-1.24+/-0.20. Taken together with the published MS metallicity toward NGC 7469, these measurements indicate a uniform abundance of ~0.1 solar along the main body of the Stream. This provides strong support to a scenario in which most of the Stream was tidally stripped from the SMC ~1.5--2.5 Gyr ago (a time at which the SMC had a metallicity of ~0.1 solar), as predicted by several N-body simulations. However, in Paper II of this series (Richter et al. 2013), we report a much higher metallicity (S/H=0.5 solar) in the inner Stream toward Fairall 9, a direction sampling a filament of the MS that Nidever et al. (2008) claim can be traced kinematically to the LMC, not the SMC. This shows that the bifurcation of the Stream is evident in its metal enrichment. Finally we measure a similar low metallicity [O/H]=[O I/H I]=-1.03+/-0.18 in the v_LSR=150 km/s cloud toward HE 0056--3622, which belongs to a population of anomalous velocity clouds near the South Galactic Pole. This suggests these clouds are associated with the Stream or more distant structures (possibly the Sculptor Group, which lies in this direction at the same velocity), rather than tracing foreground Galactic material., Comment: Accepted by ApJ; 17 pages, 11 figures

Calculations of the number of equivalence classes of Sudoku boards has to this point been done only with the aid of a computer, in part because of the unnecessarily large symmetry group used to form the classes. In particular, the relationship between relabeling symmetries and positional symmetries such as row/column swaps is complicated. In this paper we focus first on the smaller Shidoku case and show first by computation and then by using connectivity properties of simple graphs that the usual symmetry group can in fact be reduced to various minimal subgroups that induce the same action. This is the first step in finding a similar reduction in the larger Sudoku case and for other variants of Sudoku., Comment: 20 pages, 20 figures, 1 table

A symmetry group for Sudoku is complete if its action partitions the set of Sudoku boards into all possible orbits, and minimal if no group of smaller size would do the same. Previously, for a 4 x 4 Sudoku variation known as Shidoku, the authors used an analogous symmetry group to partition the set of Shidoku boards into so-called "nests" and then use the interplay between the physical and relabeling symmetries to find certain subgroups that were both complete and minimal. In this paper these same techniques are applied to find a minimal complete symmetry group for the modular magic Sudoku variation, as well as for another Sudoku variation called semi-magic Sudoku. The paper concludes with a simple computation which leads to the non-obvious fact that the full Sudoku symmetry group is, in fact, already minimal and complete.

This paper shares preliminary findings from a study of the development of leadership self-efficacy in the principals of a statewide middle-school network in the Midwest. The study was conceptualized to be carried out in three phases. As this paper was being written, the data collection for the first two phases had been completed, and preliminary analyses were being conducted. This paper is a work in progress that reflects some thinking out loud by the researcher as the study continues. The paper reports some of the preliminary findings and discusses how the findings may shape both the final phase of the study and future inquiry into the nature of principal leadership self-efficacy and the implementation of key reforms in middle-level schools. The study is examining the educational preparation, career path, and professional development of the principals; the leadership self-efficacy of the principals in relation to the major components of effective middle-level schools; the processes by which principals develop leadership self-efficacy specifically related to components of effective middle-level schools; and the process by which middle-school principal leadership self-efficacy engenders implementation of middle-level design components in the network's schools. (Author)

The purpose of this study was to develop an understanding of the relationships among principal transformational leadership, school leadership-team transformational leadership, and school culture. Twelve middle schools composed the sample population. Three surveys were used, each one focusing on collecting data related to principal leadership, team leadership, and school culture. Data were analyzed using correlational and regression statistics. Results show that the principal seems to be the primary source of identifying and articulating a vision and providing an appropriate model. Leadership teams seem to be the primary source of providing intellectual stimulation and holding high expectations. There is a mix of principal and leadership-team influence as sources of fostering commitment to group goals and providing individualized support. School culture factors reveal that the leadership team, rather than the principal, seems to exert the greatest influence upon collaborative leadership and learning partnership. The principal, rather than leadership teams, seems to exert the greatest influence upon teacher collaboration and unity of purpose. These and other findings are supportive of the current movement in education toward collaborative forms of school leadership. This study serves as a start for further exploration of principals, leadership teams, transformational leadership, and school culture. (Contains 65 references.) (RT)

The Interstate Distributive Education Curriculum Consortium (IDECC) completed 500 learning activity packages (LAPs) designed to develop 983 competencies for 69 jobs in distribution in 1974. The research was to determine: the degree to which distributive education (DE) teachers were using the IDECC LAPs, the attitudes of DE students in regard to the LAPs, and why some DE teachers were using the LAPs while others were not (measured by the Russell Scale to determine change orientation for vocational teachers). Of the 11 Consortium States, North Carolina was selected to be surveyed. Approximately 15% of North Carolina's DE teachers (38 subjects) were randomly selected, as well as a representative sample of their students, and asked to complete questionnaires. The teacher questionnaire resulted in a 73.68% response with 42.85% of the responding DE teachers reporting use of the LAPs and 57.15% reporting no use. There were 95 respondents to the student questionnaire. Usable return on the change orientation scale totaled 19. Findings and conclusions are reported according to three categories: the teacher questionnaire, the student questionnaire, and the change orientation scale. Four recommendations are presented and copies of the questionnaires are appended. (Author/MS)