Low-speed aerodynamic characteristics of a 13-percent-thick airfoil section designed for general aviation applications

Wind-tunnel tests were conducted to determine the low-speed section characteristics of a 13 percent-thick airfoil designed for general aviation applications. The results were compared with NACA 12 percent-thick sections and with the 17 percent-thick NASA airfoil. The tests were conducted ovar a Mach number range from 0.10 to 0.35. Chord Reynolds numbers varied from about 2,000,000 to 9,000,000

Animal cell division: a fellowship of the double ring?

Despite a century of research into the nature of animal cell division, a molecular explanation for the positioning of the actomyosin contractile ring has remained elusive. The discovery of a novel interaction between regulators of Rho family small GTPases has revealed a link between the mitotic microtubules and the contractile ring during the later stages of mitosis. The properties of the interacting Rho regulators suggest a molecular model for the positioning and initiation of contractile ring furrowing in animal cells. In this ‘double ring’ model, centralspindlin complexes, localized by the action of their kinesin-like protein component, position and activate a cortical equatorial ring of Rho GTPase exchange factors. The resulting ring of activated Rho would then trigger a cascade of events leading to formation and constriction of the contractile ring

The Place of Population Control in U.S. Foreign Policy

The purpose of this paper is to de­termine the propriety of incorporating an active program of birth control into U.S. foreign policy toward friendly, neutral, or uncommitted nations re­ceiving U.S. aid for economic develop­ment

Controversial and Contradictory: Historical and Contemporary Apologies for (a Lack of) Faculty Academic Freedom

Although academic freedom is considered a pillar of the academy in the United States, little legal precedent has been established to legitimize faculty academic freedom. Moreover, no legislation or case law outlines a hierarchy of academic freedom whereby institutional academic freedom may be positioned as authoritative over faculty academic freedom or vice versa. As a result, many institutions of higher education have violated academic freedom and then subsequently apologized for overstepping legal boundaries, stemming from infringing upon individuals’ rights that have not been codified through law. These apologies include a very recent one, where a university president’s remorseful remark regarding faculty academic freedom contradicted the university system’s own definition of faculty academic freedom, further blurring the concept. In this instance, the Texas Attorney General filed a brief stating faculty academic freedom did not exist, provoking an apologetic statement from the state flagship’s president. This case, along with others surveyed in this paper, illustrate a perennial struggle to outline freedoms and protections for individuals working within institutions of higher learning. These cases highlight an unresolved tension between institutional and faculty academic freedom which continue to blur the concept of academic freedom. Ultimately, balancing institutional and faculty academic freedom may require neither freedom positioned as authoritative over another. However, it is important for faculty to be aware of the specifics of their academic freedom at their institution. In this paper, we outline how one institutional system (The University of Texas) grants faculty certain freedoms but does not explicitly guarantee academic freedom, forcing apologetic institutional rhetoric

Drosophila neuroblast asymmetric divisions: cell cycle regulators, asymmetric protein localization, and tumorigenesis

Over the past decade, many of the key components of the genetic machinery that regulate the asymmetric division of Drosophila melanogaster neural progenitors, neuroblasts, have been identified and their functions elucidated. Studies over the past two years have shown that many of these identified components act to regulate the self-renewal versus differentiation decision and appear to function as tumor suppressors during larval nervous system development. In this paper, we highlight the growing number of molecules that are normally considered to be key regulators of cell cycle events/progression that have recently been shown to impinge on the neuroblast asymmetric division machinery to control asymmetric protein localization and/or the decision to self-renew or differentiate