730 research outputs found
The Wage Effects of Offshoring: Evidence from Danish Matched Worker-Firm Data
We estimate how offshoring and exporting affect wages by skill type. Our data match the population of Danish workers to the universe of private-sector Danish firms, whose trade flows are broken down by product and origin and destination countries. Our data reveal new stylized facts about offshoring activities at the firm level, and allow us to both condition our identification on within-job-spell changes and construct instruments for offshoring and exporting that are time varying and uncorrelated with the wage setting of the firm. We find that within job spells, (1) offshoring tends to increase the high-skilled wage and decrease the low-skilled wage; (2) exporting tends to increase the wages of all skill types; (3) the net wage effect of trade varies substantially across workers of the same skill type; and (4) conditional on skill, the wage effect of offshoring exhibits additional variation depending on task characteristics. We then track the outcomes for workers after a job spell and find that those displaced from offshoring firms suffer greater earnings losses than other displaced workers, and that low-skilled workers suffer greater and more persistent earnings losses than high-skilled workers.
Happiness, environmental protection and market economy
The manufacturing sector is leaving the West for Asiaās low wages and good working culture. Europe would be better off keeping these manufacturing activities, slowing down wage inflation and what is more, letting a young, cheaper workforce from the East settle down within their borders. This would aid in preserving the diverse economic structure which has been characteristic for Europe.Beside the economic growth there are two more concepts which have turned into the āholy cowsā of economics during the last fifty years. One is the need to constantly improve labor productivity and the other is increasing competitiveness of nations. The high labor productivity of some countries, induces severe unemployment in the globalized world. In the other hand it is high time we understood that it is not competition, but cooperation that brings more happiness to humanity.Should we still opt for āhappinessā and āsanityā, it is quite obvious that we all should, in economistsā terms, define our individual welfare functions corresponding to our own set of values, staying free from the influence of media, advertisements and fashion. The cornerstone to all this is the intelligent citizen who prefers local goods and services
Vertical Turbulent Cooling of the Mixed Layer in the Atlantic ITCZ and Trade Wind Regions
The causes of the seasonal cycle of vertical turbulent cooling at the base of the mixed layer are assessed using observations from moored buoys in the tropical Atlantic Intertropical Convergence Zone (ITCZ) (4Ā°N, 23Ā°W) and trade wind (15Ā°N, 38Ā°W) regions together with mixing parameterizations and a one-dimensional model. At 4Ā°N the parameterized turbulent cooling rates during 2017ā2018 and 2019 agree with indirect estimates from the climatological mooring heat budget residual: both show mean cooling of 25ā30 W m (Formula presented.) during NovemberāJuly, when winds are weakest and the mixed layer is thinnest, and 0ā10 W m (Formula presented.) during AugustāOctober. Mixing during NovemberāJuly is driven by variability on multiple time scales, including subdiurnal, near-inertial, and intraseasonal. Shear associated with tropical instability waves (TIWs) is found to generate mixing and monthly mean cooling of 15ā30 W m (Formula presented.) during MayāJuly in 2017 and 2019. At 15Ā°N the seasonal cycle of turbulent cooling is out of phase compared to 4Ā°N, with largest cooling of up to 60 W m (Formula presented.) during boreal fall. However, the relationships between wind speed, mixed layer depth, and turbulent mixing are similar: weaker mean winds and a thinner mixed layer in the fall are associated with stronger mixing and turbulent cooling of SST. These results emphasize the importance of seasonal modulations of mixed layer depth at both locations and shear from TIWs at 4Ā°N
CloudFlex: A Flexible Parametric Model for the Small-Scale Structure of the Circumgalactic Medium
We present CloudFlex, a new open-source tool for predicting the
absorption-line signatures of cool gas in galaxy halos with complex small-scale
structure. Motivated by analyses of cool material in hydrodynamical simulations
of turbulent, multiphase media, we model individual cool gas structures as
assemblies of cloudlets with a power-law distribution of cloudlet mass and relative velocities drawn from a turbulent velocity
field. The user may specify , the lower limit of the cloudlet mass
distribution (), and several other parameters that set the
total mass, size, and velocity distribution of the complex. We then calculate
the MgII 2796 absorption profiles induced by the cloudlets along pencil-beam
lines of sight. We demonstrate that at fixed metallicity, the covering fraction
of sightlines with equivalent widths Ang increases
significantly with decreasing , cool cloudlet number density
(), and cloudlet complex size. We then present a first application,
using this framework to predict the projected distribution around
galaxies. We show that the observed incidences of
Ang sightlines within 10 kpc < < 50 kpc are consistent with our
model over much of parameter space. However, they are underpredicted by models
with and , in
keeping with a picture in which the inner cool circumgalactic medium (CGM) is
dominated by numerous low-mass cloudlets ()
with a volume filling factor . When used to simultaneously model
absorption-line datasets built from multi-sightline and/or spatially-extended
background probes, CloudFlex will enable detailed constraints on the size and
velocity distributions of structures comprising the photoionized CGM.Comment: 22 pages, 7 figures. Submitted to AAS Journals, with minor
modifications. Comments welcome. (1) Co-first authors who made equal
contributions to this wor
A Two Micron All-Sky Survey View of the Sagittarius Dwarf Galaxy: II. Swope Telescope Spectroscopy of M Giant Stars in the Dynamically Cold Sagittarius Tidal Stream
We present moderate resolution (~6 km/s) spectroscopy of 284 M giant
candidates selected from the Two Micron All Sky Survey photometry. Radial
velocities (RVs) are presented for stars mainly in the south, with a number
having positions consistent with association to the trailing tidal tail of the
Sagittarius (Sgr) dwarf galaxy. The latter show a clear RV trend with orbital
longitude, as expected from models of the orbit and destruction of Sgr. A
minimum 8 kpc width of the trailing stream about the Sgr orbital midplane is
implied by verified RV members. The coldness of this stream (dispersion ~10
km/s) provides upper limits on the combined contributions of stream heating by
a lumpy Galactic halo and the intrinsic dispersion of released stars, which is
a function of the Sgr core mass. The Sgr trailing arm is consistent with a
Galactic halo containing one dominant, LMC-like lump, however some lumpier
halos are not ruled out. An upper limit to the total M/L of the Sgr core is 21
in solar units. A second structure that roughly mimics expectations for
wrapped, leading Sgr arm debris crosses the trailing arm in the Southern
Hemisphere; however, this may also be an unrelated tidal feature. Among the <13
kpc M giants toward the South Galactic Pole are some with large RVs that
identify them as halo stars, perhaps part of the Sgr leading arm near the Sun.
The positions and RVs of Southern Hemisphere M giants are compared with those
of southern globular clusters potentially stripped from the Sgr system and
support for association of Pal 2 and Pal 12 with Sgr debris is found. Our
discussion includes description of a masked-filtered cross-correlation
methodology that achieves better than 1/20 of a resolution element RVs in
moderate resolution spectra.Comment: 41 pages, 6 figures, Astronomical Journal, in press (submitted Nov.
24, 2003; tentatively scheduled for July 2004 issue
Impact of Cosmic Rays on Thermal Instability in the Circumgalactic Medium
Large reservoirs of cold (~10ā“ K) gas exist out to and beyond the virial radius in the circumgalactic medium (CGM) of all types of galaxies. Photoionization modeling suggests that cold CGM gas has significantly lower densities than expected by theoretical predictions based on thermal pressure equilibrium with hot CGM gas. In this work, we investigate the impact of cosmic-ray physics on the formation of cold gas via thermal instability. We use idealized three-dimensional magnetohydrodynamic simulations to follow the evolution of thermally unstable gas in a gravitationally stratified medium. We find that cosmic-ray pressure lowers the density and increases the size of cold gas clouds formed through thermal instability. We develop a simple model for how the cold cloud sizes and the relative densities of cold and hot gas depend on cosmic-ray pressure. Cosmic-ray pressure can help counteract gravity to keep cold gas in the CGM for longer, thereby increasing the predicted cold mass fraction and decreasing the predicted cold gas inflow rates. Efficient cosmic-ray transport, by streaming or diffusion, redistributes cosmic-ray pressure from the cold gas to the background medium, resulting in cold gas properties that are in between those predicted by simulations with inefficient transport and simulations without cosmic rays. We show that cosmic rays can significantly reduce galactic accretion rates and resolve the tension between theoretical models and observational constraints on the properties of cold CGM gas
Carbonyl Reduction by YmfI Completes the Modification of EF-P in \u3cem\u3eBacillus subtilis\u3c/em\u3e to Prevent Accumulation of an Inhibitory Modification State
Translation elongation factor P (EFāP) in Bacillus subtilis is required for a form of surface migration called swarming motility. Furthermore, B. subtilis EFāP is postātranslationally modified with a 5āaminopentanol group but the pathway necessary for the synthesis and ligation of the modification is unknown. Here we determine that the protein YmfI catalyzes the reduction of EFāPā5 aminopentanone to EFāPā5 aminopentanol. In the absence of YmfI, accumulation of 5āaminopentanonated EFāP is inhibitory to swarming motility. Suppressor mutations that enhanced swarming in the absence of YmfI were found at two positions on EFāP, including one that changed the conserved modification site (Lys 32) and abolished postātranslational modification. Thus, while modification of EFāP is thought to be essential for EFāP activity, here we show that in some cases it can be dispensable. YmfI is the first protein identified in the pathway leading to EFāP modification in B. subtilis, and B. subtilis encodes the first EFāP ortholog that retains function in the absence of modification
Exploring Halo Substructure with Giant Stars III: First Results from the Grid Giant Star Survey and Discovery of a Possible Nearby Sagittarius Tidal Structure in Virgo
We describe first results of a spectroscopic probe of selected fields from
the Grid Giant Star Survey. Multifiber spectroscopy of several hundred stars in
a strip of eleven fields along delta approximately -17^{circ}, in the range 12
<~ alpha <~ 17 hours, reveals a group of 8 giants that have kinematical
characteristics differing from the main field population, but that as a group
maintain coherent, smoothly varying distances and radial velocities with
position across the fields. Moreover, these stars have roughly the same
abundance, according to their MgH+Mgb absorption line strengths. Photometric
parallaxes place these stars in a semi-loop structure, arcing in a contiguous
distribution between 5.7 and 7.9 kpc from the Galactic center. The spatial,
kinematical, and abundance coherence of these stars suggests that they are part
of a diffuse stream of tidal debris, and one roughly consistent with a wrapped,
leading tidal arm of the Sagittarius dwarf spheroidal galaxy.Comment: 8 pages including 4 figures. Accepted for publication in ApJ
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