1,227 research outputs found
Introduction
Cambridge Studies in Nineteenth-Century Literature and Culture No. 45Copyright © 2004 Cambridge University PressFor the Victorian reading public, periodicals played a far greater role than books in shaping their understanding of new discoveries and theories in science, technology and medicine. Such understandings were formed not merely by serious scientific articles, but also by glancing asides in political reports, fictional representations, or humorous attacks in comic magazines. Ranging across diverse forms of periodicals, from top-selling religious and juvenile magazines through to popular fiction-based periodicals, and from the campaigning 'new journalism' of the late century to the comic satire of Punch, this book explores the ways in which scientific ideas and developments were presented to a variety of Victorian audiences. In addition, it offers three case studies of the representation of particular areas of science: 'baby science', scientific biography, and electricity. This intriguing collaborative volume sheds light on issues relating to history and history of science, literature, book history, and cultural and media studies
Characterizing Multi-planet Systems with Classical Secular Theory
Classical secular theory can be a powerful tool to describe the qualitative
character of multi-planet systems and offer insight into their histories. The
eigenmodes of the secular behavior, rather than current orbital elements, can
help identify tidal effects, early planet-planet scattering, and dynamical
coupling among the planets, for systems in which mean-motion resonances do not
play a role. Although tidal damping can result in aligned major axes after all
but one eigenmode have damped away, such alignment may simply be fortuitous. An
example of this is 55 Cancri (orbital solution of Fischer et al., 2008) where
multiple eigenmodes remain undamped. Various solutions for 55 Cancri are
compared, showing differing dynamical groupings, with implications for the
coupling of eccentricities and for the partitioning of damping among the
planets. Solutions for orbits that include expectations of past tidal evolution
with observational data, must take into account which eigenmodes should be
damped, rather than expecting particular eccentricities to be near zero.
Classical secular theory is only accurate for low eccentricity values, but
comparison with other results suggests that it can yield useful qualitative
descriptions of behavior even for moderately large eccentricity values, and may
have advantages for revealing underlying physical processes and, as large
numbers of new systems are discovered, for triage to identify where more
comprehensive dynamical studies should have priority.Comment: Published in Celestial Mechanics and Dynamical Astronomy, 25 pages,
10 figure
Climate change and the kidney
The worldwide increase in temperature has resulted in a marked increase in heat waves (heat extremes) that carries a markedly increased risk for morbidity and mortality. The kidney has a unique role not only in protecting the host from heat and dehydration but also is an important site of heat-associated disease. Here we review the potential impact of global warming and heat extremes on kidney diseases. High temperatures can result in increased core temperatures, dehydration, and blood hyperosmolality. Heatstroke (both clinical and subclinical whole-body hyperthermia) may have a major role in causing both acute kidney disease, leading to increased risk of acute kidney injury from rhabdomyolysis, or heat-induced inflammatory injury to the kidney. Recurrent heat and dehydration can result in chronic kidney disease (CKD) in animals and theoretically plays a role in epidemics of CKD developing in hot regions of the world where workers are exposed to extreme heat. Heat stress and dehydration also has a role in kidney stone formation, and poor hydration habits may increase the risk for recurrent urinary tract infections. The resultant social and economic consequences include disability and loss of productivity and employment. Given the rise in world temperatures, there is a major need to better understand how heat stress can induce kidney disease, how best to provide adequate hydration, and ways to reduce the negative effects of chronic heat exposure.Published versio
Supersymmetry with R-Parity Breaking: Contact Interactions and Resonance Formation in Leptonic Processes at LEP2
In supersymmetric theories with R-parity breaking, trilinear couplings of two
leptons to scalar sleptons are possible. In electron-positron collisions such
interactions would manifest themselves through contact terms in Bhabha
scattering and in annihilation to mu or tau pair Interpreting the high x, high
Q2 DIS HERA events as charm squark production with squark masses of order 200
GeV, the formation of tau sneutrinos with a mass in the range close to the LEP2
energy or even in reach, is an exciting speculation which can be investigated
in the coming LEP2 runs with energies close to 200 GeV.Comment: 13 pages, LaTex file with 3 figures, uses axodraw.sty (included).
References updated / limits from rare B decays on Yukawa couplings updated,
favoring tau-sneutrinos over mu-sneutrinos/ numerical results unchange
Complete Genome Sequence of Curtobacterium sp. Strain MR_MD2014, Isolated from Topsoil in Woods Hole, Massachusetts
Here, we present the 3,443,800-bp complete genome sequence of Curtobacterium sp. strain MR_MD2014 (phylum Actinobacteria). This strain was isolated from soil in Woods Hole, MA, as part of the 2014 Microbial Diversity Summer Program at the Marine Biological Laboratory in Woods Hole, MA
Near-IR search for lensed supernovae behind galaxy clusters: III. Implications for cluster modeling and cosmology
Massive galaxy clusters at intermediate redshifts act as gravitational lenses
that can magnify supernovae (SNe) occurring in background galaxies. We assess
the possibility to use lensed SNe to put constraints on the mass models of
galaxy clusters and the Hubble parameter at high redshift. Due to the standard
candle nature of Type Ia supernovae (SNe Ia), observational information on the
lensing magnification from an intervening galaxy cluster can be used to
constrain the model for the cluster mass distribution. A statistical analysis
using parametric cluster models was performed to investigate the possible
improvements from lensed SNe Ia for the accurately modeled galaxy cluster A1689
and the less well constrained cluster A2204. Time delay measurements obtained
from SNe lensed by accurately modeled galaxy clusters can be used to measure
the Hubble parameter. For a survey of A1689 we estimate the expected rate of
detectable SNe Ia and of multiply imaged SNe. The velocity dispersion and core
radius of the main cluster potential show strong correlations with the
predicted magnifications and can therefore be constrained by observations of
SNe Ia in background galaxies. This technique proves especially powerful for
galaxy clusters with only few known multiple image systems. The main
uncertainty for measurements of the Hubble parameter from the time delay of
strongly lensed SNe is due to cluster model uncertainties. For the extremely
well modeled cluster A1689, a single time delay measurement could be used to
determine the Hubble parameter with a precision of ~ 10%. We conclude that
observations of SNe Ia behind galaxy clusters can be used to improve the mass
modeling of the large scale component of galaxy clusters and thus the
distribution of dark matter. Time delays from SNe strongly lensed by accurately
modeled galaxy clusters can be used to measure the Hubble constant at high
redshifts.Comment: 10 pages, 8 figures, 3 tables. Accepted for publication in A&
Parkinson's disease biomarkers: perspective from the NINDS Parkinson's Disease Biomarkers Program
Biomarkers for Parkinson's disease (PD) diagnosis, prognostication and clinical trial cohort selection are an urgent need. While many promising markers have been discovered through the National Institute of Neurological Disorders and Stroke Parkinson's Disease Biomarker Program (PDBP) and other mechanisms, no single PD marker or set of markers are ready for clinical use. Here we discuss the current state of biomarker discovery for platforms relevant to PDBP. We discuss the role of the PDBP in PD biomarker identification and present guidelines to facilitate their development. These guidelines include: harmonizing procedures for biofluid acquisition and clinical assessments, replication of the most promising biomarkers, support and encouragement of publications that report negative findings, longitudinal follow-up of current cohorts including the PDBP, testing of wearable technologies to capture readouts between study visits and development of recently diagnosed (de novo) cohorts to foster identification of the earliest markers of disease onset
Chandra Detection of a TypeII Quasar at z=3.288
We report on observations of a TypeII quasar at redshift z=3.288, identified
as a hard X-ray source in a 185 ks observation with the Chandra X-ray
Observatory and as a high-redshift photometric candidate from deep, multiband
optical imaging. CXOJ084837.9+445352 (hereinafter CXO52) shows an unusually
hard X-ray spectrum from which we infer an absorbing column density N(H) =
(4.8+/-2.1)e23 / cm2 (90% confidence) and an implied unabsorbed 2-10 keV
rest-frame luminosity of L(2-10) = 3.3e44 ergs/s, well within the quasar
regime. Hubble Space Telescope imaging shows CXO52 to be elongated with slight
morphological differences between the WFPC2 F814W and NICMOS F160W bands.
Optical and near-infrared spectroscopy of CXO52 show high-ionization emission
lines with velocity widths ~1000 km/s and flux ratios similar to a Seyfert2
galaxy or radio galaxy. The latter are the only class of high-redshift TypeII
luminous AGN which have been extensively studied to date. Unlike radio
galaxies, however, CXO52 is radio quiet, remaining undetected at radio
wavelengths to fairly deep limits, f(4.8GHz) < 40 microJy. High-redshift TypeII
quasars, expected from unification models of active galaxies and long-thought
necessary to explain the X-ray background, are poorly constrained
observationally with few such systems known. We discuss recent observations of
similar TypeII quasars and detail search techniques for such systems: namely
(1) X-ray selection, (2) radio selection, (3) multi-color imaging selection,
and (4) narrow-band imaging selection. Such studies are likely to begin
identifying luminous, high-redshift TypeII systems in large numbers. We discuss
the prospects for these studies and their implications to our understanding of
the X-ray background.Comment: 28 pages, 5 figures; to appear in The Astrophysical Journa
- …