The \u3cem\u3edapE\u3c/em\u3e-encoded \u3cem\u3eN\u3c/em\u3e-Succinyl-l,l-Diaminopimelic Acid Desuccinylase from \u3cem\u3eHaemophilus influenzae\u3c/em\u3e Is a Dinuclear Metallohydrolase

The Zn K-edge extended X-ray absorption fine structure (EXAFS) spectra, of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae have been recorded in the presence of one or two equivalents of Zn(II) (i.e. [Zn_(DapE)] and [ZnZn(DapE)]). The Fourier transforms of the Zn EXAFS are dominated by a peak at ca. 2.0 Å, which can be fit for both [Zn_(DapE)] and [ZnZn(DapE)], assuming ca. 5 (N,O) scatterers at 1.96 and 1.98 Å, respectively. A second-shell feature at ca. 3.34 Å appears in the [ZnZn(DapE)] EXAFS spectrum but is significantly diminished in [Zn_(DapE)]. These data show that DapE contains a dinuclear Zn(II) active site. Since no X-ray crystallographic data are available for any DapE enzyme, these data provide the first glimpse at the active site of DapE enzymes. In addition, the EXAFS data for DapE incubated with two competitive inhibitors, 2-carboxyethylphosphonic acid and 5-mercaptopentanoic acid, are also presented

Writing-in-Action: Teaching Technical Writing through the Lens of the Reflective Practitioner

Technical writing is a critical component of technical education. Many professors who teach environmental building systems, structures, or other technical courses realize the value of assigning technical reports, which require students to gather data, to analyze that data, and to draw conclusions in a cogent manner. Those of us who teach technical courses and read our students’ reports also know how poorly written those reports typically are. Gerald Grow argued in The Writing Problems of Visual Thinkers that architects think—and therefore write—differently than the general population. If Grow is right, should we not develop a unique pedagogy for teaching architects how to communicate through technical writing? And if so, which pedagogy is correct? In The Reflective Practitioner and Educating the Reflective Practitioner, Donald Schön investigated the way that architects and other professionals work through a problem using a process of testing potential solutions, what Schön called “knowing-in-action,” “reflection-in-action,” and “reflecting on reflection-in- action” (his term for meta-thinking). Because the writing process mirrors the design process in many ways, Schön’s ideas for educating the reflective practitioner should be appropriate for teaching architecture students to write more effectively, specifically when they are assigned technical reports. This paper is the first step in a planned investigation of applying Schön’s theory of the “reflective practitioner” to the discipline of technical writing. As a first step, this paper begins with a literature review that examines writing manuals created for architects and other design professionals, identifying the way those manuals apply techniques compatible with Schön’s theories. Next, this paper offers a brief review of writing programs at several architecture schools. Following that discussion, this paper introduces some of Donald Schön’s major concepts. Finally, this paper concludes with a next steps section that outlines a proposed, long-term research project built around the proposed concept of “writing-in-action.

From Informational Barrier to Ethical Obligation: Evolving Perceptions of Teaching Energy in Architecture

In 1973, the OPEAC oil embargo shocked America out of its energy complacency—the era of cheap, seemingly limitless energy had come to an abrupt, disruptive halt. The Association of Collegiate Schools of Architecture (ACSA) responded, publishing Architecture, Energy & Education in 1984, a mere 11 years after the energy crisis began. Architecture, Energy & Education identified four barriers to teaching energy in architecture: methodological, structural, attitudinal, and informational. Of the four barriers, the informational barrier was arguably the most formidable, because energy modeling was slow and inaccessible during the 1980s. However, this situation rapidly changed in the 1990s and early 2000s during what has been called the “digital turn in architecture.” With more computing power and accessible, graphic-based interfaces, energy modeling left the realm of the programming specialist and joined the realm of the practitioner. Flash forward to today, when architects have access to nearly real-time energy modeling. This paper argues that the accessibility of such modeling mandates that architects use it for the benefit of society. In other words, the digital turn has resulted in an ethical obligation

Entropy locking

We prove that in certain one-parameter families of piecewise continuous piecewise linear interval maps with two laps, topological entropy stays constant as the parameter varies. The proof is simple and applies to a large set of families

Beyond Human RIghts

The concept of Human Rights today holds the same sanctity as the divine right of kings. Underpinning Human Rights is a concept of a Human as an enduring metaphysical entity, a concept that has been inscribed onto bodies throughout history. Human Rights, as we think of them, say, in the context of international politics, operate through an ethics of equivalence, which is to say that underpinning these rights is an assumption of equality of all Humans universally. This ethic abstracts from the very Human beings it claims to represent, and it rests on the claim that there is an essence embedded within them that is inalienable, eternal, and equivalent in every Human. The problem is that these doctrines do not actually make people equal; they instead allow Humans to be viewed in abstraction from everything that makes them the persons that they are. My task is to challenge this concept

An Analysis of Sex Differences in Teacher-Student Interaction as Manifest in Verbal and Nonverbal Behavior Cues

Purpose The purpose of this investigation was to analyze sex differences in teacher-student interaction as manifest in verbal and nonverbal behavior cues. Procedure Four female fifth and sixth-grade teachers and 105 gifted students (53 males and 52 females) were the subjects whose verbal and nonverbal behavior was recorded on 16 videotapes during 16 forty-minute class sessions. Following randomization, 8,648 behavior cues were coded on a matrix designed to accommodate a modified version of the French and Galloway IDER system of behavior analysis. Special reference was made to the sex differential as identified in the two categories of the system which specify teacher-initiated and student-initiated student talk. Thirteen null hypotheses were subjected to chi square tests for significance of difference. Findings Ten of the 13 null hypotheses were rejected. Although the percentages and ratios of the three exceptions indicated a tendency to differentiate, the differences were not statistically significant. In summary, the results were as follows: The female teachers of the fifth and sixth-grade gifted students initiated significantly more talk with male students than with female students; discriminated significantly between male and female students in favor of the male; tended to exhibit more restricting behavior toward female than toward male students; and exhibited more indirectness than directness and encouraging than restricting behavior toward both male and female students. Male students initiated talk with the female teacher significantly, more often than did female students. Conclusions Within its scope and limitations, the analysis derived the following conclusions: 1. There were manifest sex differences in teacher-student interaction in the classroom. 2. There was an apparent relationship between teacher-student sex differential and student docility. 3. There was an apparent relationship between sex differential in teacher-student interaction and teacher effectiveness. 4. There was an apparent relationship between sex differential in teacher-student interaction and student participation. 5. Students of the same sex as the teacher demonstrated more passivity in teacher-student verbal and nonverbal interaction than students of the opposite sex. 6. Opposite sex teachers manifested greater flexibility in teacher-student verbal and nonverbal behavior than teachers of the same sex as the student. 7. Opposite sex students responded more often to the teacher than students of the same sex as the teacher. 8. Opposite sex students initiated responses with the teacher more often than did same sex students. 9. Teachers tended to exhibit restricting behavior more often toward same sex students than toward opposite sex students