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Personalizing the experience : the emergence of yoga therapy
textYoga has recently been a subject of some media attention, both positive and negative. Some people advocate it for its mental and physical benefits, but others are also concerned that it might cause or lead to injury, particularly in the Western world where it's commonly seen primarily as a form of exercise. Yoga therapy emerged in part because of such concerns. Though people have used yoga to aid in health and wellness for as long as the practice has existed, the idea of yoga therapy being its own specialized field is relatively new. Yoga therapists hope to personalize the experience of yoga by working with people with various mental and physical conditions and giving them customized programs. Using quotes from professionals and people with personal yoga experience, this article explores the roots of yoga therapy, yoga itself: its praises, criticisms, science and a small sample of its plentiful history. It also addresses the definition of yoga therapy, specialties in the field, its professional organization and possibilities for the future. The question of whether yoga therapy can gain credibility and become a reliable healthcare resource has not yet been answered, though there are those who say their own personal experiences are enough to convince them one way or the other. In any case, yoga and all its various forms of practice likely won't disappear anytime soon.Journalis
The Radio-to-Submillimeter Flux Density Ratio of Galaxies as a Measure of Redshift
We re-examine the technique of determining the redshifts of galaxies from the
ratio of the submillimeter-to-radio continuum flux densities based on a
recently published catalog of 850~m sources. We derived the expected
variation of this ratio as a function of redshift incorporating the expected
average luminosity and the spectral energy distribution (SED) of dust emission
and the radio continuum. We find that the existing data for most of the high
redshift (z \gtsim 1) sources correspond to our new calculation. Amongst the
well-identified sources, there is none with an index significantly higher than
predicted. Sources which have an index lower than predicted are either within
the error zone or much lower, the latter presumably having AGN-dominated
radio-continuum emission. We find the median redshift to be , which is
consistent with that deduced by previous work () within the error. We
also discuss the various systematic effects that can affect the accuracy of the
redshift estimate. We examine other methods of redshift estimation, like
photometric ratio in the submillimeter and locating the peak of the SED in the
rest system of the objects. We conclude that while the various methods are
helpful in identifying high-redshift objects and making a crude estimate of the
redshift, they are not, at present, accurate enough for a detailed study of
redshift distribution of the submillimeter galaxies.Comment: 6 pages LaTeX, PASJ in pres
Structure of Stationary Photodissociation Fronts
The structure of stationary photodissociation fronts is revisited. H_2 self-
shielding is discussed, including the effects of line overlap. We find that
line overlap is important for N(H_2) > 10^{20} cm^{-2}. We compute multiline UV
pumping models, and compare these with simple analytic approximations for the
effects of self-shielding.
The overall fluorescent efficiency of the photodissociation front is obtained
for different ratios of chi/n_H (where chi characterizes the intensity of the
incident UV) and different dust extinction laws. The dust optical depth
tau_{pdr} to the point where 50% of the H is molecular is found to be a simple
function of a dimensionless quantity phi_0 depending on chi/n_H, the rate
coefficient for H_2 formation on grains, and the UV dust opacity. The
fluorescent efficiency of the PDR also depends primarily on phi_0 for chi<3000
and n_H<10^4 cm^{-3}; for stronger radiation fields and higher densities
radiative and collisional depopulation of vibrationally-excited levels
interferes with the radiative cascade. The emission spectrum from the PDR is
essentially independent of the color temperature of the incident UV
for T_{color}>10^4K, but shows some sensitivity to the v-J distribution of
newly-formed H_2. The 1-0S(1)/2-1S(1) and 2-1S(1)/6-4Q(1) intensity ratios, the
ortho/para ratio, and the rotational temperature in the =1 and =2 levels
are computed as functions of the temperature and density, for different values
of chi and n_H.
We apply our models to the reflection nebula NGC 2023. We are best able to
reproduce the observations with models having chi=5000, n_H=10^5 cm^{-3}.Comment: 50 pages, 24 eps figures, uses aaspp4.sty . To appear in Ap.
Whitham Deformations of Seiberg-Witten Curves for Classical Gauge Groups
Gorsky et al. presented an explicit construction of Whitham deformations of
the Seiberg-Witten curve for the \calN = 2 SUSY Yang-Mills theory.
We extend their result to all classical gauge groups and some other cases such
as the spectral curve of the affine Toda Toda system. Our
construction, too, uses fractional powers of the superpotential that
characterizes the curve. We also consider the -plane integral of
topologically twisted theories on four-dimensional manifolds with
in the language of these explicitly constructed Whitham
deformations and an integrable hierarchy of the KdV type hidden behind.Comment: latex, 39pp, no figure; some more comments and references on
integrable systems are added, and many typos are correcte
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