3,236 research outputs found
Postabortion contraception
The European Society of Contraception Expert Group on Abor
tion identified as one of its priorities to disseminate up-to-date evidence-based information on postabortion contraception to healthcare providers. A concise communication was produced which summarises the latest research in an easy-to-read format suitable for busy clinicians. Information about individual methods is presented in boxes for ease of reference
Transplanckian energy production and slow roll inflation
In this paper we investigate how the energy density due to a non-standard
choice of initial vacuum affects the expansion of the universe during
inflation. To do this we introduce source terms in the Friedmann equations
making sure that we respect the relation between gravity and thermodynamics. We
find that the energy production automatically implies a slow rolling
cosmological constant. Hence we also conclude that there is no well defined
value for the cosmological constant in the presence of sources. We speculate
that a non-standard vacuum can provide slow roll inflation on its own.Comment: 16 pages, 2 figures, version 2: minor corrections to section 4 and
references adde
On Thermalization in de Sitter Space
We discuss thermalization in de Sitter space and argue, from two different
points of view, that the typical time needed for thermalization is of order
, where is the radius of the de Sitter space in question.
This time scale gives plenty of room for non-thermal deviations to survive
during long periods of inflation. We also speculate in more general terms on
the meaning of the time scale for finite quantum systems inside isolated boxes,
and comment on the relation to the Poincar\'{e} recurrence time.Comment: 14 pages, 2 figures, latex, references added. Improved discussion in
section 3 adde
Contents of α-tocopherol and β-carotene in grasses and legumes harvested at different maturities
Concentrations of α-tocopherol and β-carotene in forage species at various maturities were studied in Scandinavia. Red clover (RC)/timothy (TI), RC/meadow fescue (MF), and
birdsfoot trefoil (BT)/TI mixtures were grown in Skara and Umeå, Sweden. RC/TI,RC/perennial ryegrass (PR), white clover/PR and BT/TI were grown in Foulum, Denmark. Forages in Sweden were cut one week before heading (BH), at heading and one week after heading of TI. The regrowth was cut six and eight weeks after each harvest in the spring growth cycle. In Denmark, one first harvest and three regrowths were taken. Results from Skara and Foulum are presented. Highest concentrations of α-tocopherol and β-carotene (mg
kg-1 DM) in legumes were found in BT grown in Skara (49.8 and 69.6 in spring growth cycle,48.1 and 79.8 in regrowth) and in Foulum (81.3 and 89.2). MF had more α-tocopherol and β-carotene than TI in the spring growth cycle (73.5 and 54.2 vs. 46.9 and 43.0 mg kg-1 DM). Highest concentrations of vitamins in the regrowth were found six weeks after BH with 71.8 and 104.8 mg α-tocopherol and 99.6 and 73.1 mg β-carotene kg-1 DM in legumes and grasses,respectively
Effects of Nonlinear Dispersion Relations on Non-Gaussianities
We investigate the effect of non-linear dispersion relations on the
bispectrum. In particular, we study the case were the modified relations do not
violate the WKB condition at early times, focusing on a particular example
which is exactly solvable: the Jacobson-Corley dispersion relation with quartic
correction with positive coefficient to the squared linear relation. We find
that the corrections to the standard result for the bispectrum are suppressed
by a factor where is the scale where the modification
to the dispersion relation becomes relevant. The modification is {\it mildly}
configuration-dependent and equilateral configurations are more suppressed with
respect to the local ones, by a factor of one percent. There is no
configuration leading to enhancements. We then analyze the results in the
framework of particle creation using the approximate gluing method of
Brandenberger and Martin, which relates more directly to the modeling of the
trans-Planckian physics via modifications of the vacuum at a certain cutoff
scale. We show that the gluing method overestimates the leading order
correction to the spectrum and bispectrum by one and two orders, respectively,
in . We discuss the various approximation and conclude that for
dispersion relations not violating WKB at early times the particle creation is
small and does not lead to enhanced contributions to the bispectrum. We also
show that in many cases enhancements do not occur when modeling the
trans-Planckian physics via modifications of the vacuum at a certain cutoff
scale. Most notably they are only of order O(1) when the Bogolyubov
coefficients accounting for particle creation are determined by the Wronskian
condition and the minimization of the uncertainty between the field and its
conjugate momentum.Comment: v1: 11 pages, 2 figures; v2: references update
Self-assessment of success of early medical abortion using a self-performed urine pregnancy test.
Purpose: The European Society of Contraception Expert Group on Abortion identified as one of its priorities the need to disseminate up-to-date evidence-based information on the use of urine pregnancy tests by women for the self assessment of the success of early medical abortion (EMA). Methods and materials: A concise communication was produced which summarises the latest research in an easy-to-read format suitable for busy clinicians. Information about individual urinary pregnancy tests is presented in boxes for ease of reference. Results: Urinary pregnancy tests (low sensitivity, high sensitivity and multilevel) can be used in combination with signs and symptoms of pregnancy to exclude an ongoing pregnancy after EMA. Conclusion: Women are able to determine the success of early medical abortion (EMA) themselves using a combination of signs, symptoms and a urine pregnancy test. This simplifies EMA, expands the range of professionals able to provide EMA and most importantly gives women greater control over their bodies and treatment
Structure of the Electric Flux in N=4 Supersymmetric Yang-Mills Theory
Correlators of Wilson loop operators with O_4=Tr(F_{\mu\nu}^2+...) are
computed in N=4 super-Yang-Mills theory using the AdS/CFT correspondence. The
results are compared with the leading order perturbative computations. As a
consequence of conformal invariance, these correlators have identical forms in
the weak and strong coupling limits for circular loops. They are essentially
different for contours not protected by conformal symmetry.Comment: 7 pages, 1 postscript figure, minor corrections and clarifying
argument
On the Monodromies of N=2 Supersymmetric Yang-Mills Theory with Gauge Group SO(2n)
We present families of algebraic curves describing the moduli-space of
supersymmetric Yang-Mills theory with gauge group . We test
our curves by computing the weak coupling monodromies and the number of
vacua.Comment: 14 pages, 5 Postscript figures, LaTeX file, uses epsf.st
Type 0A 2D Black Hole Thermodynamics and the Deformed Matrix Model
Recently, it has been proposed that the deformed matrix model describes a
two-dimensional type 0A extremal black hole. In this paper, the thermodynamics
of 0A charged non-extremal black holes is investigated. We observe that the
free energy of the deformed matrix model to leading order in 1/q can be seen to
agree to that of the extremal black hole. We also speculate on how the deformed
matrix model is able to describe the thermodynamics of non-extremal black
holes.Comment: 12 page
Erfarenheter av kontrollerad miljö i försöksdjurslokaler
It is important for many animal model studies, particularly with rodents, to be performed in a well standardized and controlled physical environment. Otherwise the observations and measurements done might create difficulties in interpretation, or the results might even be impossible to reproduce or verify in another laboratory. In the animal department of BISAM at Umea university the ventilation system was modernized in 1983-84 in the rodent facilities, with supply of air through new devices in the ceiling and exhaust of air through perforated walls on two sides of the rooms. The supply air comes from a climat chamber where the incoming air should be properly heated and humidified, as controlled by thermo- and hygrostats in the chamber outlet. The animal rooms are also equipped with a sprinkler system for additional humidification as necessary.This report presents results on controls made on temperature and humidity stability in these rebuilt rodent facilities during summer (1984) as well as winter (early 1985) conditions. The capacity of the air supply system was also controlled.In summary, the temperature in the animal rooms tended to be high during summer, and increased in periods of high out of door temperature so that in the animal cages the temperature could exceed 31 °C. The relative humidity was above accepted levels most of the time. On the other hand, during winter it seemed to be possible to keep the temperature within the desired levels, but the relative humidity was unacceptably low.With these results at hand, the air supply system was controlled for its ability mainly to humidify the air. This control was done during autumn and showed that at that time of the year the capacity was just at limit to give the desired humidity in the animal rooms. The main >>function<< of the room sprinkler system was in fact to decrease room temperature and to give unstable temperature and humidity. During winter when very cold, dry air should be heated and humidified the capacity of the climat chamber is far from sufficient. The high temperature in the rooms during summer depend upon the lack of cooling possibilities in the chamber
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