Easy Ontology without Deflationary Metaontology

This is a contribution to a symposium on Amie Thomasson’s Ontology Made Easy (2015). Thomasson defends two deflationary theses: that philosophical questions about the existence of numbers, tables, properties, and other disputed entities can all easily be answered, and that there is something wrong with prolonged debates about whether such objects exist. I argue that the first thesis (properly understood) does not by itself entail the second. Rather, the case for deflationary metaontology rests largely on a controversial doctrine about the possible meanings of ‘object’. I challenge Thomasson's argument for that doctrine, and I make a positive case for the availability of the contested, unrestricted use of ‘object’

Simulations of gas clouds in interacting galaxies

A companion can induce a variety of morphological changes in a galaxy. The author uses N-body simulations to study the effects of different kinds of perturbations on the dynamics of a disk galaxy. The model is two-dimensional, with a disk consisting of about 60,000 particles. Most of the particles (80%) represent the old stellar population with a high velocity dispersion, while the rest (20%) represent gas clouds with a low velocity dispersion. Initially, the velocity dispersion corresponds to Q = 1 for the star particles, and Q = O for the gas particles, where Q is Toomre's (1964) stability parameter. The gas clouds can collide inelastically. The disk is stabilized by a rigid halo potential, and by the random motions of the old star particles. To simulate the effect of an encounter on the disk, a companion galaxy, modelled as a point mass, can move in a co-planar orbit around the disk. A complete description of the N-body code is found in Thomasson (1989). The spiral structures caused by a companion in first a direct and then a retrograde (with respect to the rotation of the disk) parabolic orbit are presented. The associated velocity fields suggest a way to observationally distinguish between leading and trailing spiral arms. The stability of the gas component in a disk in which tidally triggered infall of gas to the center occurs is studied. Finally, the author shows how a ring of gas can form in a disk as a result of a co-planar encounter with another galaxy

The Impact of the Tau Mutation on Reproductive Function in the Golden Hamster

The tau mutation affects the circadian system of the golden hamster primarily by decreasing the period of the activity cycle from 24 to 20 hours. To study the effect of this mutation on reproductive function in the golden hamster, 3 experiments have been designed. In the first experiment, wild-type and tau female hamsters will be maintained in conditions of 14:10 LD and 11.7:8.3 LD, respectively. Blood samples will be taken and analyzed by radioimmunoassay (RIA) to determine the timing of the proestrus LH surge. In the second experiment, wild-type and tau males will be transferred to shortened photoperiods of 10:14 LD and 8.3:11.7 LD, respectively, and testicular length and width will be used as a measure of the onset of testicular regression and subsequent recrudescence. In the final experiment, wild-type and tau females will be transferred to conditions of 10:14 LD and 8.3:11.7 LD, respectively, and the time to the onset of anestrus will be recorded. It is expected that in the tau females, the preovulatory LH surge will occur 8.4 hours after lights-on. The onset of gonadal regression, recrudescence, and anestrus will occur 16.7% [(24 hours - 20 hours)/24 hours] sooner in the mutant hamster when measured in absolute time. When the time to the onset of these processes is measured in light cycles, however, it is probable that these events occur within the same number of light cycles in both the wild-types and the tau hamsters. The basic hypothesis is that the main impact of the tau mutation will be on the timing of these specific reproductive phenomena, but the fundamental physiological characteristics of these events will remain unaffected. These results would suggest that the timing of the preovulatory LH surge and the occurrence of gonadal regression, recrudescence, and anestrus in a shortened photoperiod are driven by the same neural oscillator that regulates the period of the activity cycle in the golden hamster

Journal Staff

Bakgrund: Dysfagi innebär avvikelser i den normala sväljningsfunktionen och är en vanlig funktionsnedsättning till följd av stroke. Tidigare studier har påvisat att incidensen av dysfagi i det akuta skedet efter stroke är 41-68 %. Kliniskt sett upplevs incidensen ha minskat de senaste tio åren.  Syfte: Syftet med denna studie var därför att (1) undersöka den nuvarande incidensen av orofaryngeal dysfagi hos nyinsjuknade strokepatienter, (2) undersöka hur många av deltagarna som upplever svårigheter att äta och svälja samt bedöms lida av dysfagi enligt vårdpersonal.  Metod: Sextiotre patienter inkluderades i studien, av dessa fick 42,9 % diagnosen stroke. Samtliga deltagare genomgick en dysfagibedömning inom tre dygn efter inskrivning på vårdavdelning. Denna bestod av testerna the Standardized Swallowing Assessment – Svensk översättning (SSA-S) och sväljkapacitetstest (SCT). Deltagare som inte klarade kriterierna i dessa bedömdes lida av orofaryngeal dysfagi.  Resultat: Totalt bedömdes 24 deltagare lida av orofaryngeal dysfagi. I diagnosgruppen stroke var incidensen 48,1 %. Det fanns noteringar om dysfagi i patientjournal hos 20,8 % av deltagarna som enligt testledare bedömdes lida av orofaryngeal dysfagi. Vidare upplevde 29,2 % av samtliga deltagare med orofaryngeal dysfagi samt 30,8 % i diagnosgruppen stroke svårigheter att äta eller svälja.  Slutsatser: Studien indikerar på att incidensen av orofaryngeal dysfagi hos nyinsjuknade strokepatienter inte har minskat i jämförelse med tidigare studier. Däremot tycks det finnas en låg medvetenhet om befintliga ät- och sväljningssvårigheter hos såväl patienter som vårdpersonal.Background: Dysphagia involves abnormalities in the normal swallowing function, and is a common impairment following stroke. Previous studies have shown that the incidence of dysphagia in the acute phase after stroke is 41-68 %. Clinically interprets that the incidence has declined over the past decade.  Aim: The purpose of this study was to (1) examine the current incidence of oropharyngeal dysphagia in recent-onset stroke patients, (2) investigate how many of the participants who experience difficulty eating and swallowing, and how many is believed to suffer from dysphagia according to healthcare professionals.  Method: Sixty-three patients were enrolled in the study, of whom 42,9 % were diagnosed with stroke. All participants underwent a bedside assessment of swallowing function within three days after enrollment in the nursing ward. The assessment consisted of the Standardized Swallowing Assessment - Swedish translation (SSA-S) and swallowing capacity test (SCT). Participants who did not pass the criteria of these two tests suffered from oropharyngeal dysphagia.  Results: Totally, 24 participants suffered from oropharyngeal dysphagia. The incidence in the stroke group was 48,1 %. There were notes about dysphagia in medical records in 20,8 % of the participants who were judged to suffer from oropharyngeal dysphagia by the test managers. Furthermore 29,2 % of all participants with oropharyngeal dysphagia and 30,8 % in the stroke group experienced difficulty eating or swallowing.  Conclusions: This study indicates that the incidence of oropharyngeal dysphagia in recent-onset stroke patients has not decreased in comparison with previous studies. In contrast, it appears to be a low awareness of existing eating and swallowing difficulties for both patients and healthcare professionals

Did Blue Cross and Blue Shield Suffer from Adverse Selection? Evidence from the 1950s

This paper uses a unique data set from 1957 to examine whether or not Blue Cross and Blue Shield suffered from an adverse selection death spiral after for-profit commercial insurance companies entered the market for health insurance. Results suggest that moving to experience rating may have helped the Blues counteract adverse selection in the group health insurance market. Adverse selection posed a greater problem for the Blues in the market for individual health insurance, possibly because of differences in the way the Blues screened potential enrollees relative to commercial insurance companies.

The Importance of Group Coverage: How Tax Policy Shaped U.S. Health Insurance

In 1954, the Internal Revenue Service stipulated that employer contributions to the health insurance plans of their employees were to be excluded from employee taxable income. Today, the tax subsidy is major feature of the U.S. health care market. This paper examines the initial effects of the tax subsidy on the demand for health insurance using previously unexamined data from 1953 and 1958. Results suggest that the tax subsidy increased the growth of group insurance, particularly among union members and employed persons. This is a critical effect because group insurance is not only less expensive than individual insurance, but it is also easier to obtain, and households with access to group health insurance are far more likely to purchase health insurance coverage than those without similar access. By increasing access to group insurance, the tax subsidy fostered an increase in the purchase of group health insurance by people who may not have purchased individual coverage, and generated institutional change as it cemented an employment-based system of group health insurance in the United States.

FIRST-based survey of Compact Steep Spectrum sources, IV. Multifrequency VLBA observations of very compact objects

Evidence has been mounting recently that activity in some radio-loud AGNs (RLAGNs) can cease shortly after ignition and that perhaps even a majority of very compact sources may be short-lived phenomena because of a lack of stable fuelling from the black hole. Thus, they can fade out before having evolved to large, extended objects. Re-ignition of the activity in such objects is not ruled out. With the aim of finding more examples of these objects and to investigate if they could be RLAGNs switched off at very early stages of their evolution, multifrequency VLBA observations of six sources with angular sizes significantly less than an arcsecond, yet having steep spectra, have been made. Observations were initially made at 1.65 GHz using the VLBA with the inclusion of Effelsberg telescope. The sources were then re-observed with the VLBA at 5, 8.4 and 15.4 GHz. All the observations were carried out in a snapshot mode with phase referencing. One of the sources studied, 0809+404, is dominated by a compact component but also has diffuse, arcsecond-scale emission visible in VLA images. The VLBI observations of the "core" structure have revealed that this is also diffuse and fading away at higher frequencies. Thus, the inner component of 0809+404 could be a compact fading object. The remaining five sources presented here show either core-jet or edge-brightened double-lobed structures indicating that they are in an active phase. The above result is an indication that the activity of the host galaxy of 0809+404 may be intermittent. Previous observations obtained from the literature and those presented here indicate that activity had ceased once in the past, then restarted, and has recently switched off again.Comment: 15 pages, 7 figures, matches the version printed in Astronomy & Astrophysic

Gas kinematics in massive star-forming regions from the Perseus spiral arm

We present results of a survey of 14 star-forming regions from the Perseus spiral arm in CS(2-1) and 13CO(1-0) lines with the Onsala Space Observatory 20 m telescope. Maps of 10 sources in both lines were obtained. For the remaining sources a map in just one line or a single-point spectrum were obtained. On the basis of newly obtained and published observational data we consider the relation between velocities of the "quasi-thermal" CS(2-1) line and 6.7 GHz methanol maser line in 24 high-mass star-forming regions in the Perseus arm. We show that, surprisingly, velocity ranges of 6.7 GHz methanol maser emission are predominantly red-shifted with respect to corresponding CS(2-1) line velocity ranges in the Perseus arm. We suggest that the predominance of the "red-shifted masers" in the Perseus arm could be related to the alignment of gas flows caused by the large-scale motions in the Galaxy. Large-scale galactic shock related to the spiral structure is supposed to affect the local kinematics of the star-forming regions. Part of the Perseus arm, between galactic longitudes from 85deg to 124deg, does not contain blue-shifted masers at all. Radial velocities of the sources are the greatest in this particular part of the arm, so the velocity difference is clearly pronounced. 13CO(1-0) and CS(2-1) velocity maps of G183.35-0.58 show gas velocity difference between the center and the periphery of the molecular clump up to 1.2 km/s. Similar situation is likely to occur in G85.40-0.00. This can correspond to the case when the large-scale shock wave entrains the outer parts of a molecular clump in motion while the dense central clump is less affected by the shock.Comment: accepted by Astronomy Report

Star-formation in the central kpc of the starburst/LINER galaxy NGC1614

A high angular resolution, multi-wavelength study of the LINER galaxy NGC1614 has been carried out. OVRO CO 1-0 observations are presented together with extensive multi-frequency radio continuum and HI absorption observations with the VLA and MERLIN. Toward the center of NGC1614, we have detected a ring of radio continuum emission with a radius of 300 pc. This ring is coincident with previous radio and Paschen-alpha observations. The dynamical mass of the ring based on HI absorption is 3.1 x 10E9 Msun. The peak of the integrated CO 1-0 emission is shifted by 1" to the north-west of the ring center and a significant fraction of the CO emission is associated with a crossing dust lane. An upper limit to the molecular gas mass in the ring region is 1.7 x 10E9 Msun. Inside the ring, there is a north to south elongated 1.4GHz radio continuum feature with a nuclear peak. This peak is also seen in the 5GHz radio continuum and in the CO. We suggest that the R=300 pc star forming ring represents the radius of a dynamical resonance - as an alternative to the scenario that the starburst is propagating outwards from the center into a molecular ring. The ring-like appearance probably part of a spiral structure. Substantial amounts of molecular gas have passed the radius of the ring and reached the nuclear region. The nuclear peak seen in 5GHz radio continuum and CO is likely related to previous star formation, where all molecular gas was not consumed. The LINER-like optical spectrum observed in NGC1614 may be due to nuclear starburst activity, and not to an Active Galactic Nucleus (AGN). Although the presence of an AGN cannot be excluded.Comment: Accepted by Astronomy and Astrophysics, 12 pages, 10 figure

Exploring the Racial Gap in Infant Mortality Rates, 1920-1970

This paper examines the racial gap in infant mortality rates from 1920 to 1970. Using state-level panel data with information on income, urbanization, women's education, and physicians per capita, we can account for a large portion of the racial gap in infant mortality rates between 1920 and 1945, but a smaller portion thereafter. We re-examine the post-war period in light of trends in birth weight, smoking, air pollution, breast-feeding, insurance, and hospital births.