1,051 research outputs found
Letters to Power: Public Advocacy without Public Intellectuals
“Some of the smartest thinkers on problems at home and around the world are university professors, but most of them just don’t matter in today’s great debates.” So opens a recent New York Times column headlined, “Professors, We Need You!” (February 2014) Nicholas Kristof’s thoughts on the disappearance of the professoriate elicited heated responses, both irate and enthusiastic. The flap illustrates that the place of intellectuals in American life continues to generate controversy. Samuel McCormick, as assistant professor of communications at Purdue University, joins this on-going dispute with Letters to Power, a wide-ranging and historically informed study of intellectual dissent. His subtitle—Public Advocacy without Public Intellectuals—captures his larger argument. Inasmuch as the classic public intellectuals have declined or disappeared—and here he cites my own 1987 book, The Last Intellectuals—what avenues exist today for the oppositional professor? McCormick wants to find the strategies that an independent academic can employ in an era where direct attacks on established opinion are either not possible or too dangerou
Modeling the distribution of the volcanic aerosol cloud from the 1783–1784 Laki eruption
We conducted simulations of the atmospheric transformation and transport of the emissions of the 1783–1784 Laki basaltic flood lava eruption (64.10°N, 17.15°W) using the NASA Goddard Institute for Space Studies modelE climate model coupled to a sulfur cycle chemistry model. The model simulations successfully reproduced the aerosol clouds of the 1912 Katmai and 1991 Mount Pinatubo eruptions, giving us confidence in the Laki simulations. Simulations of the Laki eruption produce peak zonal mean sulfate (SO4) concentrations of over 70 ppbv during August and into September 1783 in the upper troposphere and lower stratosphere at high latitudes. While the majority of the sulfate aerosol was removed during the fall and early winter, a significant aerosol perturbation remained into 1784. The peak SO2 gas loading was just over 37 megatons (Mt) in late June with the sulfate loading peaking in late August 1783 at 60 Mt over the average of 3 runs. This yielded a peak sulfate aerosol (75% H2SO4, 25% H2O) loading of over 80 Mt with the total aerosol produced during the entire eruption being about 165 Mt. The resulting sulfate deposition compares well with ice cores taken across Greenland. The top of atmosphere net radiative forcing peaks at −27 W/m2 over the high latitudes during late summer 1783 and produces a global mean forcing of −4 W/m2. The model results confirm that Northern Hemisphere high-latitude volcanic eruptions produce aerosols that remain mostly confined north of 30°N latitude
Characterisation of monoclonal antibodies specific for hamster leukocyte differentiation molecules
Flow cytometry was used to identify mAbs that recognize conserved epitopes on hamster leukocyte differentiation molecules (hLDM) and also to characterize mAbs developed against hLDM. Initial screening of mAbs developed against LDMs in other species yielded mAbs specific for the major histocompatibility (MHC) II molecule, CD4 and CD18. Screening of sets of mAbs developed against hLDM yielded 22 new mAbs, including additional mAbs to MHC II molecules and mAbs that recognize LDMs expressed on all leukocytes, granulocytes, all lymphocytes, all T cells, a subset of T cells, or on all B cells. Based on comparison of the pattern of expression of LDMs expressed on all hamster leukocytes with the patterns of expression of known LDMs in other species, as detected by flow cytometry (FC), four mAbs are predicted to recognize CD11a, CD44, and CD45. Cross comparison of mAbs specific for a subset of hamster T cells with a cross reactive mAb known to recognize CD4 in mice and one recognising CD8 revealed they recognize CD4. The characterization of these mAbs expands opportunities to use hamsters as an additional model species to investigate the mechanisms of immunopathogenesis of infectious diseases
An interesting candidate for isolated massive star formation in the Small Magellanic Cloud
The region of the Small Magellanic Cloud (SMC) with which this paper is
concerned contains the highest concentration of IRAS/Spitzer sources, H I
emission, and molecular clouds in this neighboring galaxy. However very few
studies have been devoted to it, despite these signs of star formation. We
present the first detailed study of the compact H II region N33 in the SMC by
placing it in a wider context of massive star formation. Moreover, we show that
N33 is a particularly interesting candidate for isolated massive star
formation. This analysis is based mainly on optical ESO NTT observations, both
imaging and spectroscopy, coupled with other archive data, notably Spitzer
images (IRAC 3.6, 4.5, 5.8, and 8.0 mic) and 2MASS observations. We derive a
number of physical characteristics of the compact H II region N33 for the first
time. This gas and dust formation of 7".4 (2.2 pc) in diameter is powered by a
massive star of spectral type O6.5-O7 V. The compact H II region belongs to a
rare class of H II regions in the Magellanic Clouds, called high-excitation
blobs (HEBs). We show that this H II region is not related to any star cluster.
Specifically, we do not find any traces of clustering around N33 on scales
larger than 10" (~ 3 pc). On smaller scales, there is a marginal stellar
concentration, the low density of which, below the 3 sigma level, does not
classify it as a real cluster. We also verify that N33 is not a member of any
large stellar association. Under these circumstances, N33 is also therefore
attractive because it represents a remarkable case of isolated massive-star
formation in the SMC. Various aspects of the relevance of N33 to the topic of
massive-star formation in isolation are discussed.Comment: 17 pages, 9 figures, 5 tables; Accepted for publication in A&
Supersymmetric Dark Matter
There is almost universal agreement among astronomers that most of the mass
in the Universe and most of the mass in the Galactic halo is dark. Many lines
of reasoning suggest that the dark matter consists of some new, as yet
undiscovered, weakly-interacting massive particle (WIMP). There is now a vast
experimental effort being surmounted to detect WIMPS in the halo. The most
promising techniques involve direct detection in low-background laboratory
detectors and indirect detection through observation of energetic neutrinos
from annihilation of WIMPs that have accumulated in the Sun and/or the Earth.
Of the many WIMP candidates, perhaps the best motivated and certainly the most
theoretically developed is the neutralino, the lightest superpartner in many
supersymmetric theories. We review the minimal supersymmetric extension of the
Standard Model and discuss prospects for detection of neutralino dark matter.
We review in detail how to calculate the cosmological abundance of the
neutralino and the event rates for both direct- and indirect-detection schemes,
and we discuss astrophysical and laboratory constraints on supersymmetric
models. We isolate and clarify the uncertainties from particle physics, nuclear
physics, and astrophysics that enter at each step in the calculation. We
briefly review other related dark-matter candidates and detection techniques.Comment: The complete postscript file is available at
ftp://ftp.npac.syr.edu/pub/users/jungman/susyreview/susyreview.ps.Z The TeX
source and figures (plain TeX; macros included) are at
ftp://ftp.npac.syr.edu/pub/users/jungman/susyreview/susyreview.tar.Z Full
paper NOT submitted to lanl archive: table of contents only. To appear in
Physics Report
Reclaiming heritage: colourization, culture wars and the politics of nostalgia
This article considers the discursive continuities between a specifically liberal defence of cultural patrimony, evident in the debate over film colourization, and the culture war critique associated with neo-conservatism. It examines how a rhetoric of nostalgia, linked to particular ideas of authenticity,canonicity and tradition,has been mobilized by the right and the left in attempts to stabilize the confguration and perceived transmission of American cultural identity. While different in scale, colourization and multiculturalism were seen to create respective (postmodern) barbarisms against which defenders of culture, heritage and good taste could unite. I argue that in its defence of the ‘classic’ work of art, together with principles of aesthetic distinction and the value of cultural inheritance,the anti-colourization lobby helped enrich and legitimize a discourse of tradition that, at the end of the 1980s, was beginning to reverberate powerfully in the conservative challenge to a ‘crisis’ within higher education and the humanities. This article attempts to complicate the contemporary politics of nostalgia, showing how a defence of cultural patrimony has distinguished major and minor culture wars, engaging left and right quite differently but with similar presuppositions
Experimental Design for the Evaluation of Detection Techniques of Hidden Corrosion Beneath the Thermal Protective System of the Space Shuttle Orbiter
The United States Space Operational Space Shuttle Fleet Consists of three shuttles with an average age of 19.7 years. Shuttles are exposed to corrosive conditions while undergoing final closeout for missions at the launch pad and extreme conditions during ascent, orbit, and descent that may accelerate the corrosion process. Structural corrosion under TPS could progress undetected (without tile removal) and eventually result in reduction in structural capability sufficient to create negative margins of . safety and ultimate loss of local structural capability
The role of glucocorticoids in the induction of zinc-α2-glycoprotein expression in adipose tissue in cancer cachexia
Loss of adipose tissue in cancer cachexia in mice bearing the MAC16 tumour arises from an increased lipid mobilisation through increased expression of zinc-α2-glycoprotein (ZAG) in white (WAT) and brown (BAT) adipose tissue. Glucocorticoids have been suggested to increase ZAG expression, and this study examines their role in cachexia and the mechanisms involved. In mice bearing the MAC16 tumour, serum cortisol concentrations increased in parallel with weight loss, and the glucocorticoid receptor antagonist RU38486 (25 mg kg−1) attenuated both the loss of body weight and ZAG expression in WAT. Dexamethasone (66 μg kg−1) administration to normal mice produced a six-fold increase in ZAG expression in both WAT and BAT, which was also attenuated by RU38486. In vitro studies using 3T3-L1 adipocytes showed dexamethasone (1.68 μM) to stimulate lipolysis and increase ZAG expression, and both were attenuated by RU38486 (10 μM), anti-ZAG antibody (1 μgml−1), and the β3-adrenoreceptor (β3-AR) antagonist SR59230A (10 μM). Zinc-α2-glycoprotein also increased its own expression and this was attenuated by SR59230A, suggesting that it was mediated through the β3-AR. This suggests that glucocorticoids stimulate lipolysis through an increase in ZAG expression, and that they are responsible for the increase in ZAG expression seen in adipose tissue of cachectic mice
Are oxygen and neon enriched in PNe and is the current solar Ne/O abundance ratio underestimated?
A thorough critical literature survey has been carried out for reliable
measurements of oxygen and neon abundances of planetary nebulae (PNe) and HII
regions. By contrasting the results of PNe and of HII regions, we aim to
address the issues of the evolution of oxygen and neon in the interstellar
medium (ISM) and in the late evolutionary phases of low- and intermediate-mass
stars (LIMS), as well as the currently hotly disputed solar Ne/O abundance
ratio. Through the comparisons, we find that neon abundance and Ne/O ratio
increase with increasing oxygen abundance in both types of nebulae, with
positive correlation coefficients larger than 0.75. The correlations suggest
different enrichment mechanisms for oxygen and neon in the ISM, in the sense
that the growth of neon is delayed compared to oxygen. The differences of
abundances between PNe and HII regions, are mainly attributed to the results of
nucleosynthesis and dredge-up processes that occurred in the progenitor stars
of PNe. We find that both these alpha-elements are significantly enriched at
low metallicity (initial oxygen abundance <= 8.0) but not at metallicity higher
than the SMC. The fact that Ne/O ratios measured in PNe are almost the same as
those in HII regions, regardless of the metallicity, suggests a very similar
production mechanism of neon and oxygen in intermediate mass stars (IMS) of low
initial metallicities and in more massive stars, a conjecture that requires
verification by further theoretical studies. This result also strongly suggests
that both the solar neon abundance and the Ne/O ratio should be revised upwards
by ~0.22 dex from the Asplund, Grevesse & Sauval values or by ~0.14 dex from
the Grevesse & Sauval values.Comment: 5 pages, 2 figures, to be published in MNRAS Lette
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