1,783 research outputs found
Residualism and Rural America: A Decade Later
Rural residents, more so than their urban counterparts are popularly believed to view the use of social welfare programs as appropriate only as last (residual) means of obtaining help. The extent to which this belief reflected reality was assessed by Camasso and Moore (1985) a decade ago using data from a 1980 survey of Pennsylvania residents. Congruent with the residualist hypotheses they found that rural residents were less supportive than urban people of social welfare programming, even when the effects of various personal sociodemographic characteristics were controlled. This paper replicates the workof Camasso and Moore by reporting findings from a similar study carried out a decade later. Although the relative economic and social capital disadvantage of rural people has increased across time, they persist in being more likely than urban residents to express residualist views toward social welfare programming, Implications of these results are discussed
Long photoperiods sustain high pH in Arctic kelp forests
Concern on the impacts of ocean acidification on calcifiers, such as bivalves, sea urchins, and foraminifers, has led to efforts to understand the controls on pH in their habitats, which include kelp forests and seagrass meadows. The metabolism of these habitats can lead to diel fluctuation in pH with increases during the day and declines at night, suggesting no net effect on pH at time scales longer than daily. We examined the capacity of subarctic and Arctic kelps to up-regulate pH in situ and experimentally tested the role of photoperiod in determining the capacity of Arctic macrophytes to up-regulate pH. Field observations at photoperiods of 15 and 24 hours in Greenland combined with experimental manipulations of photoperiod show that photoperiods longer than 21 hours, characteristic of Arctic summers, are conducive to sustained up-regulation of pH by kelp photosynthesis. We report a gradual increase in pH of 0.15 units and a parallel decline in pCO2 of 100 parts per million over a 10-day period in an Arctic kelp forest over midsummer, with ample scope for continued pH increase during the months of continuous daylight. Experimental increase in CO2 concentration further stimulated the capacity of macrophytes to deplete CO2 and increase pH. We conclude that long photoperiods in Arctic summers support sustained up-regulation of pH in kelp forests, with potential benefits for calcifiers, and propose that this mechanism may increase with the projected expansion of Arctic vegetation in response to warming and loss of sea ice.The study was funded by the Danish Environmental Protection Agency within the Danish Cooperation for Environment in the Arctic. It is also a contribution to the Greenland Ecosystem Monitoring program (www.G-E-M.dk) and the Arctic Science Partnership (www.asp-net.org). M.S.-M. was supported by a Fundación “La Caixa” fellowship (Spain). We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe
Screening current effects in Josephson junction arrays
The purpose of this work is to compare the dynamics of arrays of Josephson
junctions in presence of magnetic field in two different frameworks: the so
called XY frustrated model with no self inductance and an approach that takes
into account the screening currents (considering self inductances only). We
show that while for a range of parameters the simpler model is sufficiently
accurate, in a region of the parameter space solutions arise that are not
contained in the XY model equations.Comment: Figures available from the author
The variational quantum eigensolver self-consistent field method within a polarizable embedded framework
We formulate and implement the Variational Quantum Eigensolver Self
Consistent Field (VQE-SCF) algorithm in combination with polarizable embedding
(PE), thereby extending PE to the regime of quantum computing. We test the
resulting algorithm, PE-VQE-SCF, on quantum simulators and demonstrate that the
computational stress on the quantum device is only slightly increased in terms
of gate counts compared to regular VQE-SCF. On the other hand, no increase in
shot noise was observed. We illustrate how PE-VQE-SCF may lead to the modeling
of real chemical systems using a simulation of the reaction barrier of the
Diels-Alder reaction between furan and ethene as an example.Comment: 19 pages, 5 figures, submitted to Journal of Chemical Physic
Morphological Instabilities in a growing Yeast Colony: Experiment and Theory
We study the growth of colonies of the yeast Pichia membranaefaciens on
agarose film. The growth conditions are controlled in a setup where nutrients
are supplied through an agarose film suspended over a solution of nutrients. As
the thickness of the agarose film is varied, the morphology of the front of the
colony changes. The growth of the front is modeled by coupling it to a
diffusive field of inhibitory metabolites. Qualitative agreement with
experiments suggests that such a coupling is responsible for the observed
instability of the front.Comment: RevTex, 4 pages and 3 figure
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