To know one's own: estate surveying and the representation of the land in early modern England.

Published as 'To Know One's Own: Estate Surveying and the Representation of the Land in Early Modern England', Huntington Library Quarterly, 56 (4), Autumn 1993, pp 333-357. © 1993 by the Regents of the University of California. Copying and permissions notice: Authorization to copy this content beyond fair use (as specified in Sections 107 and 108 of the U. S. Copyright Law) for internal or personal use, or the internal or personal use of specific clients, is granted by the Regents of the University of California for libraries and other users, provided that they are registered with and pay the specified fee via Rightslink® on Caliber (http://caliber.ucpress.net/) or directly with the Copyright Clearance Center, http://www.copyright.com. Images reproduced with permission of the Huntington Library

The literary culture of early Stuart libeling.

Reproduced with permission of the publisher. © 2000 the University of Chicago Press.Australian Research Council; University of Sydney U2000 postdoctoral fellowship

Researchers’ Views on Ethical Challenges in Healthcare Cluster-randomized Trials

• Cluster-randomized trials (CRTs) commonly used in education, public health, healthcare and social sciences • Groups of individuals randomly assigned to receive one of 2 (or more) comparator interventions • Effect of interventions evaluated after collecting data from individual group members • Ethics guidelines developed for oversight of research enrolling individual subjects • Little specific guidance for ethical conduct of CRTs • Lack of guidance may lead to variability in ethics reviews between jurisdictions and over tim

Ethical Challenges in Cluster Randomized Trials

Research Questions: This dissertation examines how ethical challenges in CRTs are addressed in practice. This dissertation also provides guidance as to who must be considered a research subject in a CRT, and when consent must be sought from research subjects. Methods: The association between consent practices in healthcare CRTs and particular trial features were examined using multivariable logistic regression modelling. Information on ethical challenges encountered by CRT researchers in practice was obtained by analyzing semi-structured interviews with experienced CRT investigators. Two normative questions, “Who is the research subject in CRTs?” and “When is consent required in CRTs?” were also addressed. Results: Consent in CRTs is associated with smaller cluster sizes, and the use of individual-level experimental and data collection interventions. CRT researchers are most concerned with issues around informed consent, and less concerned with issues related to the analysis of harms and benefits in CRTs. Research subjects are individuals who are intervened upon by investigators; who interact with investigators; or who contribute identifiable private information. Consent must be sought for CRT participation from research subjects. Consent is not required from cluster members who are not research subjects. Consent after randomization of clusters is permissible if necessary. Some CRTs may meet criteria for a waiver of informed consent. Conclusions: This dissertation describes the state of the art of ethics practices in CRTs, and presents guidance around consent issues in CRTs that will inform the development of international ethics guidelines for CRTs

The relationship between cell size and cell fate in Volvox carteri

In Volvox carteri development, visibly asymmetric cleavage divisions set apart large embryonic cells that will become asexual reproductive cells (gonidia) from smaller cells that will produce terminally differentiated somatic cells. Three mechanisms have been proposed to explain how asymmetric division leads to cell specification in Volvox: (a) by a direct effect of cell size (or a property derived from it) on cell specification, (b) by segregation of a cytoplasmic factor resembling germ plasm into large cells, and (c) by a combined effect of differences in cytoplasmic quality and cytoplasmic quantity. In this study a variety of V. carteri embryos with genetically and experimentally altered patterns of development were examined in an attempt to distinguish among these hypotheses. No evidence was found for regionally specialized cytoplasm that is essential for gonidial specification. In all cases studied, cells with a diameter > approximately 8 microns at the end of cleavage--no matter where or how these cells had been produced in the embryo--developed as gonidia. Instructive observations in this regard were obtained by three different experimental interventions. (a) When heat shock was used to interrupt cleavage prematurely, so that presumptive somatic cells were left much larger than they normally would be at the end of cleavage, most cells differentiated as gonidia. This result was obtained both with wild-type embryos that had already divided asymmetrically (and should have segregated any cytoplasmic determinants involved in cell specification) and with embryos of a mutant that normally produces only somatic cells. (b) When individual wild-type blastomeres were isolated at the 16-cell stage, both the anterior blastomeres that normally produce two gonidia each and the posterior blastomeres that normally produce no gonidia underwent modified cleavage patterns and each produced an average of one large cell that developed as a gonidium. (c) When large cells were created microsurgically in a region of the embryo that normally makes only somatic cells, these large cells became gonidia. These data argue strongly for a central role of cell size in germ/soma specification in Volvox carteri, but leave open the question of how differences in cell size are actually transduced into differences in gene expression