From Development To Evolution: The Re-Establishment Of The Alexander Kowalevsky Medal

The Saint Petersburg Society of Naturalists has reinstated the Alexander O. Kowalevsky Medal. This article announces the winners of the first medals and briefly reviews the achievements of A.O. Kowalevsky,the Russian comparative embryologist whose studies on amphioxus, tunicates and germ layer homologies pioneered evolutionary embryology and confirmed the evolutionary continuity between invertebrates and vertebrates. In re-establishing this international award, the Society is pleased to recognize both the present awardees and the memory of Kowalevsky, whose work pointed to that we now call evolutionary developmental biology

Investigating dark matter substructure with pulsar timing: I. Constraints on ultracompact minihalos

Small-scale dark matter structure within the Milky Way is expected to affect pulsar timing. The change in gravitational potential induced by a dark matter halo passing near the line of sight to a pulsar would produce a varying delay in the light travel time of photons from the pulsar. Individual transits produce an effect that would either be too rare or too weak to be detected in 30-year pulsar observations. However, a population of dark matter subhalos would be expected to produce a detectable effect on the measured properties of pulsars if the subhalos constitute a significant fraction of the total halo mass. The effect is to increase the dispersion of measured period derivatives across the pulsar population. By statistical analysis of the ATNF pulsar catalogue, we place an upper limit on this dispersion of $\log \sigma_{\dot{P}} \leq -17.05$. We use this to place strong upper limits on the number density of ultracompact minihalos within the Milky Way. These limits are completely independent of the particle nature of dark matter.Comment: 9 pages, 5 figues, includes erratum published in MNRA

A Symbiotic View Of Life: We Have Never Been Individuals

The notion of the biological individual is crucial to studies of genetics, immunology, evolution, development, anatomy, and physiology. Each of these biological subdisciplines has a specific conception of individuality, which has historically provided conceptual contexts for integrating newly acquired data. During the past decade, nucleic acid analysis, especially genomic sequencing and high-throughput RNA techniques, has challenged each of these disciplinary definitions by finding significant interactions of animals and plants with symbiotic microorganisms that disrupt the boundaries that heretofore had characterized the biological individual. Animals cannot be considered individuals by anatomical or physiological criteria because a diversity of symbionts are both present and functional in completing metabolic pathways and serving other physiological functions. Similarly, these new studies have shown that animal development is incomplete without symbionts. Symbionts also constitute a second mode of genetic inheritance, providing selectable genetic variation for natural selection. The immune system also develops, in part, in dialogue with symbionts and thereby functions as a mechanism for integrating microbes into the animal-cell community. Recognizing the holobiont -the multicellular eukaryote plus its colonies of persistent symbionts-as a critically important unit of anatomy, development, physiology, immunology, and evolution opens up new investigative avenues and conceptually challenges the ways in which the biological subdisciplines have heretofore characterized living entities

Nonresident Hunters in North Dakota: Characteristics, Expenditures, Harvest

This study was initiated when a need for data on nonresident hunter expenditures and activities was identified in a departmental research effort considering alternative uses of wetlands. Also, nonresident hunting license sales are an important source of revenue for the North Dakota State Game and Fish Department. In 1976, 7.5 percent of the hunters in the state were nonresidents, but nonresident license sales accounted for 27 percent of all state hunting license revenue. The data in this report fill a void that existed in estimating the economic significance of all hunting in North Dakota since a similar study dealing with resident hunters was conducted in the department in 1973.Resource /Energy Economics and Policy,

The Role of Tacit Routines in Coordinating Activity

We explore the influence of tacit routines in obtaining coordination. Our experiment uses simple laboratory "firms," in which we interfere with one kind of firm's ability to develop tacit routines. Thus, our firms vary in the degree to which they rely on this kind of knowledge – instead of other, explicit, mechanisms – for obtaining coordination. We find that interfering with the development of tacit routines harms firms’ ability to coordinate. We then explore the extent to which firms are able to transfer their ability to coordinate activity, either to a new domain or to new members. Our results indicate that tacit routines transfer more easily than other mechanisms to a new, but closely related, domain. However, routine-based firms perform slightly worse in their ability to incorporate new members

Economic Impact of Flooding on Agricultural Production in Northeast Central North Dakota

The Devils Lake Basin is a closed basin in which a number of damaging floods have been recorded in recent decades. Flooding occurs in the spring as a result of snowmelt and in the summer as a result of severe summer rainstorms. The main flood problem in the Basin is damage to agricultural land and crops. This report presents a procedure for estimating flood damages in the Basin and preliminary flood damage estimates are given. Also included are selected statistics on wetland and drainage in the Devils Lake Basin.Production Economics, Resource /Energy Economics and Policy,

Strong-field tidal distortions of rotating black holes: III. Embeddings in hyperbolic 3-space

In previous work, we developed tools for quantifying the tidal distortion of a black hole's event horizon due to an orbiting companion. These tools use techniques which require large mass ratios (companion mass $\mu$ much smaller than black hole mass $M$), but can be used for arbitrary bound orbits, and for any black hole spin. We also showed how to visualize these distorted black holes by embedding their horizons in a global Euclidean 3-space, ${\mathbb{E}}^3$. Such visualizations illustrate interesting and important information about horizon dynamics. Unfortunately, we could not visualize black holes with spin parameter $a_* > \sqrt{3}/2 \approx 0.866$: such holes cannot be globally embedded into ${\mathbb{E}}^3$. In this paper, we overcome this difficulty by showing how to embed the horizons of tidally distorted Kerr black holes in a hyperbolic 3-space, ${\mathbb{H}}^3$. We use black hole perturbation theory to compute the Gaussian curvatures of tidally distorted event horizons, from which we build a two-dimensional metric of their distorted horizons. We develop a numerical method for embedding the tidally distorted horizons in ${\mathbb{H}}^3$. As an application, we give a sequence of embeddings into ${\mathbb{H}}^3$ of a tidally interacting black hole with spin $a_*=0.9999$. A small amplitude, high frequency oscillation seen in previous work shows up particularly clearly in these embeddings.Comment: 10 pages, 6 figure

Burrowing apparatus

A soil burrowing mole is described in which a housing has an auger blade wound around a front portion. This portion is rotatable about a housing longitudinal axis relative to an externally finned housing rear portion upon operation of driving means to cause an advance through soil and the like. The housing carries a sensor sensitive to deviation from a predetermined path and to which is coupled means for steering the housing to maintain the path

Precision Electro-Weak and Hadronic Luminosity Calculations

We have used YFS Monte Carlo techniques to obtain per-mil level accuracy for the Bhabha scattering cross section used in the luminosity monitor in electro-weak scattering experiments. We will describe techniques for extending these methods for use in the W production luminosity cross section for hadron colliders.Comment: 8 pages (LaTex) with 5 figures (EPS). Presented by S.A. Yost at the Third International Symposium on Quantum Theory and Symmetries, Cincinnati, Sept. 10 - 14, 200