6,153 research outputs found
Field Theory Entropy, the -theorem and the Renormalization Group
We consider entropy and relative entropy in Field theory and establish
relevant monotonicity properties with respect to the couplings. The relative
entropy in a field theory with a hierarchy of renormalization group fixed
points ranks the fixed points, the lowest relative entropy being assigned to
the highest multicritical point. We argue that as a consequence of a
generalized theorem Wilsonian RG flows induce an increase in entropy and
propose the relative entropy as the natural quantity which increases from one
fixed point to another in more than two dimensions.Comment: 25 pages, plain TeX (macros included), 6 ps figures. Addition in
title. Entropy of cutoff Gaussian model modified in section 4 to avoid a
divergence. Therefore, last figure modified. Other minor changes to improve
readability. Version to appear in Phys. Rev.
Dimensional Crossover in the Large N Limit
We consider dimensional crossover for an Landau-Ginzburg-Wilson model
on a -dimensional film geometry of thickness in the large -limit. We
calculate the full universal crossover scaling forms for the free energy and
the equation of state. We compare the results obtained using ``environmentally
friendly'' renormalization with those found using a direct, non-renormalization
group approach. A set of effective critical exponents are calculated and
scaling laws for these exponents are shown to hold exactly, thereby yielding
non-trivial relations between the various thermodynamic scaling functions.Comment: 25 pages of PlainTe
Chromogranin A in uremia: Progressive retention of immunoreactive fragments
Chromogranin A in uremia: Progressive retention of immunoreactive fragments. Chromogranin A is a soluble protein that is stored and released with catecholamines from their secretory vesicles. Its measurement is a probe of exocytotic sympathoadrenal activity, and in plasma it may also be a useful tool in the diagnosis of peptide producing endocrine neoplasms. Because we have found that chromogranin A is elevated in secondary (uremic) hyperparathyroidism, we systematically investigated the influence of renal dysfunction and its attendant hyperparathyroidism on chromogranin A in several subject groups: normal controls (serum creatinine≤1.2 mg/dl), nonazotemic renal transplant recipients, nonazotemic subjects with glomerular disease (serum creatinine between 1.2 and 2 mg/dl), mid-range renal disease subjects (serum creatinine between 2 and 7.5 mg/dl), and end-stage renal disease subjects (serum creatinine <7.5 mg/dl). Plasma chromogranin A rose with deterioration of renal function, and the rise was independent of etiologic diagnosis, blood pressure, or indices of sympathoadrenal activity or hyperparathyroidism. Size fractionation of uremic plasma by gel filtration, and immunoextraction by region-specific anti-chromo-granin A (anti-N-terminal, anti-C-terminal, and antimid-molecule) antibodies suggested that chromogranin A immunoreactivity circulates in uremia as lower molecular weight fragments of the parent chromogranin A molecule, with mid-molecule fragments the major constituent. This immunoreactivity is only minimally removed by peritoneal dialysis and is not at all hemodialyzable. The uremia-dose-dependent accumulation of chromogranin A immunoreactive fragments in renal failure suggests that the kidney is a major site of disposition or removal of the immunoreactivity. Furthermore, lack of detectable chromogranin A immunoreactivity in normal subjects' urine suggests that the immunoreactivity is destroyed as it is removed by the kidney. We conclude that plasma chromogranin A increases in proportion to degree of renal insufficiency and that renal function must therefore be controlled when using plasma chromogranin A in the investigation of amine or peptide hormone storage and release
The Specific Heat of a Ferromagnetic Film.
We analyze the specific heat for the vector model on a -dimensional
film geometry of thickness using ``environmentally friendly''
renormalization. We consider periodic, Dirichlet and antiperiodic boundary
conditions, deriving expressions for the specific heat and an effective
specific heat exponent, \alpha\ef. In the case of , for , by
matching to the exact exponent of the two dimensional Ising model we capture
the crossover for \xi_L\ra\infty between power law behaviour in the limit
{L\over\xi_L}\ra\infty and logarithmic behaviour in the limit
{L\over\xi_L}\ra0 for fixed , where is the correlation length in
the transverse dimensions.Comment: 21 pages of Plain TeX. Postscript figures available upon request from
[email protected]
Dallas with balls: televized sport, soap opera and male and female pleasures
Two of the most popular of television genres, soap opera and sports coverage have been very much differentiated along gender lines in terms of their audiences. Soap opera has been regarded very much as a 'gynocentric' genre with a large female viewing audience while the audiences for television sport have been predominantly male. Gender differentiation between the genres has had implications for the popular image of each. Soap opera has been perceived as inferior; as mere fantasy and escapism for women while television sports has been perceived as a legitimate, even edifying experience for men.
In this article the authors challenge the view that soap opera and television sport are radically different and argue that they are, in fact, very similar in a number of significant ways. They suggest that both genres invoke similar structures of feeling and sensibility in their respective audiences and that television sport is a 'male soap opera'. They consider the ways in which the viewing context of each genre is related to domestic life and leisure, the ways in which the textual structure and conventions of each genre invoke emotional identification, and finally, the ways in which both genres re-affirm gender identities
Simulational Study on Dimensionality-Dependence of Heat Conduction
Heat conduction phenomena are studied theoretically using computer
simulation. The systems are crystal with nonlinear interaction, and fluid of
hard-core particles. Quasi-one-dimensional system of the size of is simulated. Heat baths are put in both end:
one has higher temperature than the other. In the crystal case, the interaction
potential has fourth-order non-linear term in addition to the harmonic
term, and Nose-Hoover method is used for the heat baths. In the fluid case,
stochastic boundary condition is charged, which works as the heat baths.
Fourier-type heat conduction is reproduced both in crystal and fluid models in
three-dimensional system, but it is not observed in lower dimensional system.
Autocorrelation function of heat flux is also observed and long-time tails of
the form of , where denotes the dimensionality of the
system, are confirmed.Comment: 4 pages including 3 figure
Disease prevention strategies for QX disease (Marteilia sydneyi) of Sydney rock oysters (Saccostrea glomerata)
The Sydney rock oyster (Saccostrea glomerata) forms the basis of an important aquaculture industry on the east coast of Australia. During the 1970s, production of S. glomerata began to decline, in part as a result of mortalities arising from Queensland unknown (QX) disease. Histological studies implicated the paramyxean parasite Marteilia sydneyi in the disease outbreaks. Disease zoning was implemented to prevent the spread of M. sydneyi-infected oysters. This control measure hindered rock oyster farming, which historically has relied on transferring wild-caught spat between estuaries for on-growing to market size and has not prevented the subsequent occurrence of QX disease in the Georges and Hawkesbury rivers in central New South Wales. Management of QX disease has been hampered by the complicated life cycle of M. sydneyi, with outbreaks of QX disease likely to be regulated by a combination of the abundance of intermediate host of M. sydneyi, environmental stressors, and the immunocompetence of S. glomerata. The future of the Sydney rock oyster industry relies on understanding these factors and progressing the industry from relying on farming wild-caught seed to the successful commercialization of hatchery-produced QX-resistant S. glomerata
Response of a mixed grass prairie to an extreme precipitation event
Citation: Concilio, A. L., Prevey, J. S., Omasta, P., O'Connor, J., Nippert, J. B., & Seastedt, T. R. (2015). Response of a mixed grass prairie to an extreme precipitation event. Ecosphere, 6(10), 12. doi:10.1890/es15-00073.1Although much research has been conducted to measure vegetation response to directional shifts in climate change drivers, we know less about how plant communities will respond to extreme events. Here, we evaluate the response of a grassland community to an unprecedented 43 cm rainfall event that occurred in the Front Range of Colorado in September, 2013 using vegetation plots that had been monitored for response to simulated precipitation changes since 2011. This rain caused soils to stay at or above field capacity for multiple days, and much of the seed bank germinated following the early autumn event. Annual introduced grasses, especially cheatgrass (Bromus tectorum), and several introduced forbs demonstrated strong positive increases in cover the following growing season. Native cool season grasses and native forbs showed limited changes in absolute cover despite continued high soil water availability, while native warm season grasses increased in cover the following summer. Treatments that previously altered the amounts and seasonality of rainfall during the 2011-2013 interval showed legacy effects impacting cover responses of introduced species and warm-season native grasses. Resin bag estimates of inorganic nitrogen flux resulting from the event indicated twice as much nitrogen movement compared to any previous collections during the 2011-2013 interval. Nitrogen additions to a subset of plots made in spring of 2014 demonstrated that the relative cover of introduced species could be further increased with additional soil nitrogen. Collectively, these results support the contention that extreme precipitation events can favor species already benefiting from other environmental change drivers
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