Arguments in a Sartorial Mode, or the Asymmetries of History and Philosophy of Science

History of science and philosophy of science are not perfectly complementary disciplines. Several important asymmetries govern their relationship. These asymmetries, concerning levels of analysis, evidence, theories, writing, and training show that to be a decent philosopher of science is more difficult than being a decent historian. But to be a good historian-well, the degree of difficulty is reversed

Target shape dependence in a simple model of receptor-mediated endocytosis and phagocytosis

Phagocytosis and receptor-mediated endocytosis are vitally important particle uptake mechanisms in many cell types, ranging from single-cell organisms to immune cells. In both processes, engulfment by the cell depends critically on both particle shape and orientation. However, most previous theoretical work has focused only on spherical particles and hence disregards the wide-ranging particle shapes occurring in nature, such as those of bacteria. Here, by implementing a simple model in one and two dimensions, we compare and contrast receptor-mediated endocytosis and phagocytosis for a range of biologically relevant shapes, including spheres, ellipsoids, capped cylinders, and hourglasses. We find a whole range of different engulfment behaviors with some ellipsoids engulfing faster than spheres, and that phagocytosis is able to engulf a greater range of target shapes than other types of endocytosis. Further, the 2D model can explain why some nonspherical particles engulf fastest (not at all) when presented to the membrane tip-first (lying flat). Our work reveals how some bacteria may avoid being internalized simply because of their shape, and suggests shapes for optimal drug delivery.Comment: 18 pages, 5 figure

SS433's jet trace from ALMA imaging and Global Jet Watch spectroscopy: evidence for post-launch particle acceleration

We present a comparison of Doppler-shifted H-alpha line emission observed by the Global Jet Watch from freshly-launched jet ejecta at the nucleus of the Galactic microquasar SS433 with subsequent ALMA imaging at mm-wavelengths of the same jet ejecta. There is a remarkable similarity between the transversely-resolved synchrotron emission and the prediction of the jet trace from optical spectroscopy: this is an a priori prediction not an a posteriori fit, confirming the ballistic nature of the jet propagation. The mm-wavelength of the ALMA polarimetry is sufficiently short that the Faraday rotation is negligible and therefore that the observed E-vector directions are accurately orthogonal to the projected local magnetic field. Close to the nucleus the B-field vectors are perpendicular to the direction of propagation. Further out from the nucleus, the B-field vectors that are coincident with the jet instead become parallel to the ridge line; this occurs at a distance where the jet bolides are expected to expand into one another. X-ray variability has also been observed at this location; this has a natural explanation if shocks from the expanding and colliding bolides cause particle acceleration. In regions distinctly separate from the jet ridge line, the fractional polarisation approaches the theoretical maximum for synchrotron emission.Comment: To appear in ApJ Letter

The Relationship of Reading and Spelling Ability At Various School Levels

Current emphasis in spelling and reading appears to be on the unitary nature of the child\u27s development especially in relation to the language arts. While the writer is interested in the analysis of reading abilities and spelling ability in order to determine the fundamental language abilities common to both skills, the specific problem of this investigation is to, discover the consistency of the relationship of spelling and reading abilities of pupils from the fifth grade through the ninth grade inclusive . This relationship refers to the linear correlation relationship derived from the use of standardized tests. The particular phases of the general problem to which special attention is directed are: (1) Is the development in reading ability and spelling ability parallel throughout these various grade levels? ( 2) How does this relationship on one level compare with the relationship on the next higher level? (3) Does the relationship change with children of different mental ages? (4) Is this relationship a constant or a variable as between different school systems

Resurrecting the Fairness Doctrine: The Quandary of Enforcement Continues

Despite its repeal in 1987, the fairness doctrine remains one of the most controversial issues in broadcast regulation today. Since the doctrine\u27s demise, Congress has tried twice unsuccessfully to revive this content-specific regulation which required broadcasters to actively search for controversial issues of importance and present a balance of viewpoints in programming exploring those issues. This article suggests a new standard of reviewing fairness complaints at renewal time which creates a strong presumption in favor of the broadcaster. Part I of the article focuses on the development of the fairness doctrine throughout its short history. In particular, it traces the historical underpinnings of broadcast regulation examining the intent and purpose of the fairness provision. Part II analyzes the judicial and quasi-judicial enforcement of this regulation, particularly with respect to political broadcasting. Part III traces the demise of the Doctrine and the attempts to revive it. Part IV outlines the presumption in favor of the broadcaster at license renewal time and concludes that this alternative essentially frees broadcasters from defending their records, yet still provides a window of opportunity for groups validly claiming biased broadcasting