Evolution of the bilaterian body plan: What have we learned from annelids?

Annelids, unlike their vertebrate or fruit fly cousins, are a bilaterian taxon often overlooked when addressing the question of body plan evolution. However, recent data suggest that annelids offer unique insights on the early evolution of spiral cleavage, anteroposterior axis formation, body axis segmentation, and head versus trunk distinction.

Inversion of the chordate body axis: Are there alternatives?

One major morphological difference between chordates and annelids or arthropods is the opposite orientation of the nerve cord and heart. A long-standing proposal is that the chordate axis evolved by inverting the body of an ancestor with the annelid/arthropod orientation. However, the data can also be explained by a common ancestor with diffuse dorsoventral organization, followed by oppositely directed condensation of the nerve cord and relocation of the heart in the two lines.

SPO21 Is Required for Meiosis-specific Modification of the Spindle Pole Body in Yeast

During meiosis II in the yeast Saccharomyces cerevisiae, the cytoplasmic face of the spindle pole body changes from a site of microtubule initiation to a site of de novo membrane formation. These membranes are required to package the haploid meiotic products into spores. This functional change in the spindle pole body involves the expansion and modification of its cytoplasmic face, termed the outer plaque. We report here that SPO21 is required for this modification. The Spo21 protein localizes to the spindle pole in meiotic cells. In the absence of SPO21 the structure of the outer plaque is abnormal, and prospore membranes do not form. Further, decreased dosage of SPO21 leaves only two of the four spindle pole bodies competent to generate membranes. Mutation of CNM67, encoding a known component of the mitotic outer plaque, also results in a meiotic outer plaque defect but does not block membrane formation, suggesting that Spo21p may play a direct role in initiating membrane formation.

Expression of Drosophila mushroom body mutations in alternative genetic backgrounds: a case study of the mushroom body miniature gene (mbm).

Mutations in 12 genes regulating Drosophila melanogaster mushroom body (MB) development were each studied in two genetic backgrounds. In all cases, brain structure was qualitatively or quantitatively different after replacement of the "original" genetic background with that of the Canton Special wild-type strain. The mushroom body miniature gene (mbm) was investigated in detail. mbm supports the maintenance of MB Kenyon cell fibers in third instar larvae and their regrowth during metamorphosis. Adult mbm1 mutant females are lacking many or most Kenyon cell fibers and are impaired in MB-mediated associative odor learning. We show here that structural defects in mbm1 are apparent only in combination with an X-linked, dosage-dependent modifier (or modifiers). In the Canton Special genetic background, the mbm1 anatomical phenotype is suppressed, and MBs develop to a normal size. However, the olfactory learning phenotype is not fully restored, suggesting that submicroscopic defects persist in the MBs. Mutant mbm1 flies with full-sized MBs have normal retention but show a specific acquisition deficit that cannot be attributed to reductions in odor avoidance, shock reactivity, or locomotor behavior. We propose that polymorphic gene interactions (in addition to ontogenetic factors) determine MB size and, concomitantly, the ability to recognize and learn odors.

The Mos/mitogen-activated protein kinase (MAPK) pathway regulates the size and degradation of the first polar body in maturing mouse oocytes.

Mos is an upstream activator of mitogen-activated protein kinase (MAPK) and, in mouse oocytes, is responsible for metaphase II arrest. This activity has been likened to its function in Xenopus oocytes as a component of cytostatic factor. Thus, Mos-deficient female mice (MOS-/-) are less fertile and oocytes derived from these animals fail to arrest at metaphase II and undergo parthenogenetic activation [Colledge, W. H., Carlton, M. B. L., Udy, C. B. & Evans, M. J. (1994) Nature (London) 370, 65-68 and Hashimoto, N., Watanabe, N., Furuta. Y., Tamemoto, B., Sagata, N., Yokoyama, M., Okazaki, K., Nagayoshi, M., Takeda, N., Ikawa, Y. & Aizawa, S. (1994) Nature (London) 370, 68-71]. Here we show that maturing MOS-/- oocytes fail to activate MAPK throughout meiosis, while p34cdc2 kinase activity is normal until late in metaphase II when it decreases prematurely. Phenotypically, the first meiotic division of MOS-/- oocytes frequently resembles mitotic cleavage or produces an abnormally large polar body. In these oocytes, the spindle shape is altered and the spindle fails to translocate to the cortex, leading to the establishment of an altered cleavage plane. Moreover, the first polar body persists instead of degrading and sometimes undergoes an additional cleavage, thereby providing conditions for parthenogenesis. These studies identify meiotic spindle formation and programmed degradation of the first polar body as new and important roles for the Mos/MAPK pathway.

The social evil in Chicago: a study of existing conditions with recommendations by the Vice Commission of Chicago, a municipal body appointed by the Mayor and the City Council of the City of Chicago, and submitted as its report to the Mayor and City Council of Chicago

Preface -- Outline of study -- Resolution of appreciation -- Introduction and summary -- Proposed ordinance -- Recommendations -- Existing conditions in Chicago -- The social evil and the saloon -- The social evil and the police -- Sources of supply -- Child protection and education -- Rescue and reform -- The social evil and its medical aspects -- Appendices: Text of revised statutes of Illinois and ordinances of the City of Chicago ; Tables ; Exhibits.

The Extensive (but Fragile) Authority of the WTO Appellate Body

The authority of an international court (IC) is not necessarily evolutionary and its development unidirectional. This article addresses the authority of the Appellate Body (AB) of the World Trade Organization (WTO) and shows how it rapidly and almost immediately became extensive, but has since exhibited signs of becoming more fragile. The article applies a typology of IC authority developed by Alter, Helfer and Madsen (2014) and explains the transformation from narrow authority (a dispute resolution venue under the GATT based on political negotiations) to extensive authority (a judicialized WTO dispute settlement system with a sophisticated case law) and presents empirical indicators of the rise of the AB’s authority. Such rapid development of extensive authority is arguably a unique case in international politics at the multilateral level. That authority nonetheless remains fragile, and shows signs that it could decline significantly for reasons we explain.

Mass distribution of the human body using biostereometrics. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

The American vegetable practice, or, A new and improved guide to health. : Designed for the use of families. : In six parts. Part I. Concise view of the human body, with engraved and wood-cut illustrations. Part II. Glance at the old school practice of physic. Part III. Vegetable materia medica, with colored illustrations. Part IV. Compounds. Part V. Practice of medicine, based upon what are deemed correct physiological and pathological principles. Part VI. Guide for women, containing a simplified treatise on childbirth, with a description of the diseases peculiar to females and infants. /

Errata and advertisement for "New England Depot. D.L. Hale" at end of v. 2.

Experimental evaluation of the deployment of an air bag restraint using human subjects (stationary body buck). Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Lipogenesis in the animal body, with special reference to the physiology of the goose,

Bibliographical foot-notes.