Calibration standard for dynamic evaluation of a profile-plotter

Template is used for evaluation of the dynamic characteristics and accuracy of the plotter. It has a profile composed of surfaces parallel to and at known distances from a reference plane, plane, the diverse surfaces being connected by slopes of known angles and blended by cylindrical developments of known radii

European Springtails Orchesella cincta (L.) and O. villosa (L.) (Collembola: Entomobryidae): Vagabond Species of the Nearctic Region

North American specimens of the European invasive springtail Orchesella cincta (L.) were compared to several published European haplotypes in a phylogenetic framework using likelihood methods based on a portion of cytochrome oxidase II (cox2). Our analyses provide direct evidence of at least two distinct introductions of this invasive to North America from different regions of Europe. Additional introduction events cannot be ruled out because detection is limited by extremely low sequence divergence among populations inhabiting different regions of the continent. Orchesella villosa (L.), another invasive from Europe, is another candidate for multiple introductions. Herein we include the cox2 sequence from single specimens of O. villosa from Maine and Oregon. Although these two specimens are identical in sequence, they differ from a published sequence from a European specimen by 15%, indicating significant undocumented genetic variation in the natal range of O. villosa. Additional sampling of Nearctic populations of O. villosa might reveal the same situation reported herein for O. cincta

Novice Teachers\u27 Sensemaking in an Era of Accountability: Implications for School Leaders

The purpose of this research study was to examine how novice teachers make sense of the realities of their chosen profession, given their initial motivations for entering the profession. My research into teacher motivation and retention provided evidence that teachers did enter the field for altruistic reasons and that as many as 50% of all new teachers in urban schools did not last beyond five years. When they begin teaching, they find a field that is heavily impacted by strict accountability standards and required mandated testing. I used Sensemaking Theory and Self-Determination Theory to examine how beginning teachers make sense of their chosen profession, how the principles of Self-Determination Theory interact with sensemaking to influence teachers’ decisions to stay or leave teaching, and whether teachers would indicate points of influence that school leaders had used to help them decide to keep teaching. I used narrative inquiry to interview 21 teachers who were in their 3rd to 6th year of teaching from public schools at different grade levels and specializations. My interviews suggest that teachers who decide early in their lives to become teachers were more likely to have trouble making sense of the urban school classroom compared to teachers who decided to become teachers as adults, especially after working in a different field. This suggests that school leaders should consider teachers’ motivation to enter teaching as they design professional development opportunities and assign teachers to teams. This dissertation is available in open access at Antioch University Repository and Archive (AURA), https://aura.antioch.edu/ and OhioLINK ETD Center, http://etd.ohiolink.edu/

Characterizing Block Graphs in Terms of their Vertex-Induced Partitions

Given a finite connected simple graph $G=(V,E)$ with vertex set $V$ and edge set $E\subseteq \binom{V}{2}$, we will show that $1.$ the (necessarily unique) smallest block graph with vertex set $V$ whose edge set contains $E$ is uniquely determined by the $V$-indexed family ${\bf P}_G:=\big(\pi_0(G^{(v)})\big)_{v \in V}$ of the various partitions $\pi_0(G^{(v)})$ of the set $V$ into the set of connected components of the graph $G^{(v)}:=(V,\{e\in E: v\notin e\})$, $2.$ the edge set of this block graph coincides with set of all $2$-subsets $\{u,v\}$ of $V$ for which $u$ and $v$ are, for all $w\in V-\{u,v\}$, contained in the same connected component of $G^{(w)}$, $3.$ and an arbitrary $V$-indexed family ${\bf P}p=({\bf p}_v)_{v \in V}$ of partitions $\pi_v$ of the set $V$ is of the form ${\bf P}p={\bf P}p_G$ for some connected simple graph $G=(V,E)$ with vertex set $V$ as above if and only if, for any two distinct elements $u,v\in V$, the union of the set in ${\bf p}_v$ that contains $u$ and the set in ${\bf p}_u$ that contains $v$ coincides with the set $V$, and $\{v\}\in {\bf p}_v$ holds for all $v \in V$. As well as being of inherent interest to the theory of block graphs, these facts are also useful in the analysis of compatible decompositions and block realizations of finite metric spaces