912 research outputs found
âThe Rise of the Hansâ: A Critique
âRise of the Hans,â by Joel Kotkin, is a troubling article to find published in a high-profile venue such as Foreign Policy. It reinforces misleading ideas about China and is problematic for a variety of specific reasons, the biggest of which has to do with Kotkinâs use of key terms
The Chinese Typewriter
Tom Mullaney, who will be familiar to regular followers of this site thanks to the podcasts heâs done for us (such as this one on the 1989 protests and this one onLast Days of Old Beijing), recently mentioned that he is currently writing a history of the Chinese typewriter, as actual and imagined object.
He sent this piece introducing the subject, which moves between popular culture and the history of technology (how often are rapper MC Hammer, IBM engineers, diplomats from China, and Homer Simpson alluded to in a single story?), while illuminating some of the directions that thinking about the challenges involved in creating machines capable of reproducing Chinese characters have led:
Propelled to international stardom by his multi-platinum single âU Canât Touch This,â MC Hammer is perhaps not the first person one thinks of when studying Western stereotypes about China. Remarkably, however, the music video accompanying his 1990 hit featured one bit of fancy footwork that has helped perpetuate a distorted view of China dating back more than one hundred years. Known as the âChinese typewriter,â the dance features MC Hammer side-stepping in rapid, frenetic movements, choreography that would gain immense popularity to become one of the defining dances of the early nineties.
Why the Chinese Typewriter? Hammerâs dance, the idea went, was supposed to mimic the alien virtuosity of a Chinese typist as he navigates what Hammer assumed must be an absurdly massive keyboard crowded with tens of thousands of characters.
Whereas the Oakland-born artist may be credited with bringing parachute pants into mainstream culture, the same cannot be said of his ideas regarding our Pacific neighbor. The Chinese typewriter has been an object of ridicule in the West since its inception at the turn of the century. For over a hundred years, writers in the United States and Europe have derived a unique sense of cultural and technological superiority by portraying the apparatus as absurdly large, painfully slow, and prohibitively complex
Modeling the connection between ultraviolet and infrared galaxy populations across cosmic times
Using a phenomenological approach, we self-consistently model the redshift evolution of the ultraviolet (UV) and infrared (IR) luminosity functions across cosmic time, as well as a range of observed IR properties of UV-selected galaxy population. This model is an extension of the 2SFM (2 star-formation modes) formalism, which is based on the observed "main-sequence" of star-forming galaxies, i.e. a strong correlation between their stellar mass and their star formation rate (SFR), and a secondary population of starbursts with an excess of star formation. The balance between the UV light from young, massive stars and the dust-reprocessed IR emission is modeled following the empirical relation between the attenuation (IRX for IR excess hereafter) and the stellar mass, assuming a scatter of 0.4\,dex around this relation. We obtain a good overall agreement with the measurements of the IR luminosity function up to z~3 and the UV luminosity functions up to z~6, and show that a scatter on the IRX-M relation is mandatory to reproduce these observables. We also naturally reproduce the observed, flat relation between the mean IRX and the UV luminosity at LUV>109.5 Lâ. Finally, we perform predictions of the UV properties and detectability of IR-selected samples and the vice versa, and discuss the results in the context of the UV-rest-frame and sub-millimeter surveys of the next decade
Revealing the differences in the SMBH accretion rate distributions of starburst and non-starburst galaxies
We infer and compare the specific X-ray luminosity distributions for a sample of massive (i.e. log10(M*/Mâ) > 10.5) galaxies split according to their far-infrared-derived star-forming properties (i.e. starburst and non-starburst) and redshift. We model each distribution as a power law with an upper and lower turnover, and adopt a maximum likelihood method to include information from non-detections in the form of upper limits. When we use our inferred distributions to calculate the ratios of high to low sLX active galactic nuclei (AGNs; corresponding to above and below 0.1λEdd, respectively), we find that starbursts have significantly higher proportions of high sLX AGNs compared to their non-starburst counterparts. These findings help explain the increase in average X-ray luminosity in bins of increasing star formation rates reported by previous studies
Preferences of women for web-based nutritional information in pregnancy
Objectives During pregnancy, women are increasingly turning to web-based resources for information. This study examined the use of web-based nutritional information by women during pregnancy and explored their preferences. Study design Cross-sectional observational study. Methods Women were enrolled at their convenience from a large maternity hospital. Clinical and sociodemographic details were collected and women\u27s use of web-based resources was assessed using a detailed questionnaire. Results Of the 101 women, 41.6% were nulliparous and the mean age was 33.1 years (19â47 years). All women had internet access and only 3% did not own a smartphone. Women derived pregnancy-related nutritional information from a range of online resources, most commonly: What to Expect When You\u27re Expecting (15.1%), Babycenter (12.9%), and Eumom (9.7%). However, 24.7% reported using Google searches. There was minimal use of publically funded or academically supported resources. The features women wanted in a web-based application were recipes (88%), exercise advice (71%), personalized dietary feedback (37%), social features (35%), videos (24%) and cooking demonstrations (23%). Conclusions This survey highlights the risk that pregnant women may get nutritional information from online resources which are not evidence-based. It also identifies features that women want from a web-based nutritional resource
The forbidden high ionisation line region of the type 2 quasar Q1131+16: a clear view of the inner face of the torus?
We present spectroscopic observations of the type 2 quasar SDSS
J11311.05+162739.5 (Q1131+16 hereafter; z=0.1732), which has the richest
spectrum of forbidden high ionisation lines (FHIL, e.g. [Fe \textsc{vii}], [Fe
\textsc{x}], [Fe \textsc{xi}] and [Ne \textsc{v}]) yet reported for an AGN, as
well as unusually strong [O \textsc{iii}]4363 emission. The study of
this object provides a rare opportunity to investigate the physical conditions
and kinematics of the region(s) emitting the FHILs. By comparison with
photoionisation model results, we find that the FHIL region has high densities
(10 cm\textsuperscript{-3}) and ionisation
parameters (-1.5 log[U] 0), yet its kinematics are similar to those of
the low ionisation emission line region detected in the same object (FWHM
36030 km/s), with no evidence for a significant shift between the
velocity centroid of the FHILs and the rest frame of the host galaxy. The
deduced physical conditions lie between those of the Broad-Line (n
cm\textsuperscript{-3}) and Narrow-Line Regions (
cm\textsuperscript{-3}) of active galactic nuclei (AGN), and we demonstrate
that the FHIL regions must be situated relatively close to the illuminating AGN
(0.32 50pc). We suggest that the inner torus wall is the
most likely location for the FHIL region, and that the unusual strength of the
FHILs in this object is due to a specific viewing angle of the far wall of the
torus, coupled with a lack of dust on larger scales that might otherwise
obscure our view of the torus.Comment: Accepted for publication in the Monthly Notices of the Royal
Astronomical Society (3rd of March 2011). 23 Pages (including tables 5 and 6
in the source file), 21 figure
Updating quasar bolometric luminosity corrections. II. Infrared bolometric corrections
We present infrared bolometric luminosity corrections derived from the
detailed spectral energy distributions of 62 bright quasars of low- to
moderate-redshift (z=0.03-1.4). At 1.5, 2, 3, 7, 12, 15, and 24 microns we
provide bolometric corrections of the mathematical forms L_iso=\zeta \lambda
L_\lambda and log(L_iso)=A+B log(\lambda L_\lambda). Bolometric corrections for
radio-loud and radio-quiet objects are consistent within 95% confidence
intervals, so we do not separate them. Bolometric luminosities estimated using
these corrections are typically smaller than those derived from some commonly
used in the literature. We investigate the possibility of a luminosity
dependent bolometric correction and find that, while the data are consistent
with such a correction, the dispersion is too large and the luminosity range
too small to warrant such a detailed interpretation. Bolometric corrections at
1.5 m are appropriate for objects with properties that fall in the range
log(L_bol)=45.4-47.3 and bolometric corrections at all other wavelengths are
appropriate for objects with properties that fall in the range
log(L_bol)=45.1-47.0.Comment: 13 pages, 4 tables, 8 figures, accepted to MNRA
The Spitzer discovery of a galaxy with infrared emission solely due to AGN activity
We present a galaxy (SAGE1CJ053634.78-722658.5) at a redshift of 0.14 of
which the IR is entirely dominated by emission associated with the AGN. We
present the 5-37 um Spitzer/IRS spectrum and broad wavelength SED of
SAGE1CJ053634, an IR point-source detected by Spitzer/SAGE (Meixner et al
2006). The source was observed in the SAGE-Spec program (Kemper et al., 2010)
and was included to determine the nature of sources with deviant IR colours.
The spectrum shows a redshifted (z=0.14+-0.005) silicate emission feature with
an exceptionally high feature-to-continuum ratio and weak polycyclic aromatic
hydrocarbon (PAH) bands. We compare the source with models of emission from
dusty tori around AGNs from Nenkova et al. (2008). We present a diagnostic
diagram that will help to identify similar sources based on Spitzer/MIPS and
Herschel/PACS photometry. The SED of SAGE1CJ053634 is peculiar because it lacks
far-IR emission and a clear stellar counterpart. We find that the SED and the
IR spectrum can be understood as emission originating from the inner ~10 pc
around an accreting black hole. There is no need to invoke emission from the
host galaxy, either from the stars or from the interstellar medium, although a
possible early-type host galaxy cannot be excluded based on the SED analysis.
The hot dust around the accretion disk gives rise to a continuum, which peaks
at 4 um, whereas the strong silicate features may arise from optically thin
emission of dusty clouds within ~10 pc around the black hole. The weak PAH
emission does not appear to be linked to star formation, as star formation
templates strongly over-predict the measured far-IR flux levels. The SED of
SAGE1CJ053634 is rare in the local universe but may be more common in the more
distant universe. The conspicuous absence of host-galaxy IR emission places
limits on the far-IR emission arising from the dusty torus alone.Comment: Accepted for publication in A&A, 7 pages, 6 figure
Jet interactions with a giant molecular cloud in the Galactic centre and ejection of hypervelocity stars
The hypervelocity OB stars in the Milky Way Galaxy were ejected from the
central regions some 10-100 million years ago. We argue that these stars, {as
well as many more abundant bound OB stars in the innermost few parsecs,} were
generated by the interactions of an AGN jet from the central black hole with a
dense molecular cloud. Considerations of the associated energy and momentum
injection have broader implications for the possible origin of the Fermi
bubbles and for the enrichment of the intergalactic medium.Comment: 4 pages, 1 figure. Astronomy and Astrophysics Letters, in pres
Physical activity attitudes, intentions and behaviour among 18-25 year olds: a mixed method study
Peer reviewedPublisher PD
- âŠ