412 research outputs found
Application of ovariovit to improve diary cows conception rate
This article presents the results of a study on the efficiency of fertilization by treatment with ovariovit and liarsin. The study was conducted on the facility of “Kamyshinskoe” farm in Shemonaikhinskiy region of Vostochno-Khazakhstanskaya oblast in the Republic of Kazakhstan. Animals of different ages and with the same productivity were selected for the experiment. Treatment of animals was carried out after gynecological clinical examination. The examination of animals was performed by rectal and biophysical methods. The efficiency of homeopathic and hormonal treatments of the dairy cows to increase fertility were studied. The performed study enabled evaluation of various schemes for increasing the fertility of dairy cows. The results of the study showed a higher efficiency with the treatment of homeopathic drugs
Particle Dark Energy
We explore the physics of a gas of particles interacting with a condensate
that spontaneously breaks Lorentz invariance. The equation of state of this gas
varies from 1/3 to less than -1 and can lead to the observed cosmic
acceleration. The particles are always stable. In our particular class of
models these particles are fermions with a chiral coupling to the condensate.
They may behave as relativistic matter at early times, produce a brief period
where they dominate the expansion with w<0 today, and behave as matter at late
time. There are no small parameters in our models, which generically lead to
dark energy clustering and, depending on the choice of parameters, smoothing of
small scale power.Comment: 8 pages, 5 figures; minor update with added refs; version appearing
in Phys. Rev.
Line Broadening in Field Metal-poor Red Giant and Red Horizontal Branch Stars
We report 349 radial velocities for 45 metal-poor field red giant and red
horizontal branch stars. We have have identified one new spectroscopic binary,
HD 4306, and one possible such system, HD 184711. We also report 57 radial
velocities for 11 of the 91 stars reported on previously by Carney et al.
(2003). As was found in the previous study, radial velocity "jitter" is present
in many of the most luminous stars. Excluding stars showing spectroscopic
binary orbital motion, all 7 of the red giants with M(V) <= -2.0 display
jitter, as well as 3 of the 14 stars with -2.0 <= M(V) <= -1.4. We have also
measured line broadening in all of the new spectra, using synthetic spectra as
templates. The most luminous red giants show significant line broadening, as do
many of the red horizontal branch stars, and we discuss briefly possible
causes.Comment: To appear in the Astronomical Journa
Disparate Osteogenic Response of Mandible and Iliac Crest Bone Marrow Stromal Cells to Pamidronate
OBJECTIVE Long-term administration of intravenous bisphosphonates like pamidronate is associated with jaw osteonecrosis but axial and appendicular bones are unaffected. Pathogenesis of bisphosphonate-associated jaw osteonecrosis may relate to skeletal-site specific effects of bisphosphonates on osteogenic differentiation of bone marrow stromal cells (BMSCs) of orofacial and axial/appendicular bones. This study evaluated and compared skeletal site-specific osteogenic response of mandible (orofacial bone) and iliac crest (axial bone) human BMSCs to pamidronate. MATERIALS AND METHODS Mandible and iliac crest BMSCs from six normal healthy volunteers were established in culture and tested with pamidronate to evaluate and compare cell survival, osteogenic marker alkaline phosphatase, osteoclast differentiation in co-cultures with CD34+ hematopoietic stem cells, gene expression of receptor activator of NFκB ligand (RANKL) and osteoprotegerin, and in vivo bone regeneration. BRESULTS Mandible BMSCs were more susceptible to pamidronate than iliac crest BMSCs based on decreased cell survival, lower alkaline phosphatase production and structurally less organized in vivo bone regeneration. Pamidronate promoted higher RANKL gene expression and osteoclast recruitment by mandible BMSCs. CONCLUSION Mandible and iliac crest BMSC survival and osteogenic differentiation are disparately affected by pamidronate to favor dysregulated mandible bone homeostasis
HAT-P-3b: A heavy-element rich planet transiting a K dwarf star
We report the discovery of a Jupiter-size planet transiting a relatively
bright (V = 11.56) and metal-rich early K dwarf star with a period of about 2.9
days. On the basis of follow-up photometry and spectroscopy we determine the
mass and radius of the planet, HAT-P-3b, to be M_p = 0.599 +/- 0.026 M_Jup and
R_p = 0.890 +/- 0.046 R_Jup. The relatively small size of the object for its
mass implies the presence of about 75 Earth masses worth of heavy elements (1/3
of the total mass) based on current theories of irradiated extrasolar giant
planets, similar to the mass of the core inferred for the transiting planet HD
149026b. The bulk density of HAT-P-3b is found to be rho_p = 1.06 +/- 0.17
g/cm^3, and the planet orbits the star at a distance of 0.03894 AU. Ephemerides
for the transit centers are T_c = 2,454,218.7594 +/- 0.0029 + N (2.899703 +/-
0.000054) (HJD).Comment: To appear in ApJ
HAT-P-4b: A metal-rich low-density transiting hot Jupiter
We describe the discovery of HAT-P-4b, a low-density extrasolar planet
transiting BD+36 2593, a V = 11.2 mag slightly evolved metal-rich late F star.
The planet's orbital period is 3.056536+/-0.000057 d with a mid-transit epoch
of 2,454,245.8154 +/- 0.0003 (HJD). Based on high-precision photometric and
spectroscopic data, and by using transit light curve modeling, spectrum
analysis and evolutionary models, we derive the following planet parameters:
Mp= 0.68 +/- 0.04 MJ, Rp= 1.27 +/- 0.05 RJ, rho = 0.41 +/- 0.06 g cm-3 and a =
0.0446 +/- 0.0012 AU. Because of its relatively large radius, together with its
assumed high metallicity of that of its parent star, this planet adds to the
theoretical challenges to explain inflated extrasolar planets.Comment: 5 pages, accepted for publication in ApJ
HAT-P-5b: A Jupiter-like hot Jupiter Transiting a Bright Star
We report the discovery of a planet transiting a moderately bright (V =
12.00) G star, with an orbital period of 2.788491 +/-0.000025 days. From the
transit light curve we determine that the radius of the planet is Rp = 1.257
+/- 0.053 RJup. HAT-P-5b has a mass of Mp = 1.06 +/- 0.11 MJup, similar to the
average mass of previously-known transiting exoplanets, and a density of rho =
0.66 +/- 0.11 g cm^-3 . We find that the center of transit is Tc =
2,454,241.77663 +/- 0.00022 (HJD), and the total transit duration is 0.1217 +/-
0.0012 days.Comment: 5 pages, submitted to APJ
HAT-P-18b and HAT-P-19b: Two Low-Density Saturn-Mass Planets Transiting Metal-Rich K Stars
We report the discovery of two new transiting extrasolar planets. HAT-P-18b
orbits the V=12.759 K2 dwarf star GSC 2594-00646, with a period
P=5.508023+-0.000006 d, transit epoch Tc=2454715.02174+-0.00020 (BJD), and
transit duration 0.1131+-0.0009 d. The host star has a mass of 0.77+-0.03 Msun,
radius of 0.75+-0.04 Rsun, effective temperature 4803+-80 K, and metallicity
[Fe/H]=+0.10+-0.08. The planetary companion has a mass of 0.197+-0.013 Mjup,
and radius of 0.995+-0.052 Rjup yielding a mean density of 0.25+-0.04 g cm-3.
HAT-P-19b orbits the V=12.901 K1 dwarf star GSC 2283-00589, with a period
P=4.008778+-0.000006 d, transit epoch Tc=2455091.53417+-0.00034 (BJD), and
transit duration 0.1182+-0.0014 d. The host star has a mass of 0.84+-0.04 Msun,
radius of 0.82+-0.05 Rsun, effective temperature 4990+-130 K, and metallicity
[Fe/H]=+0.23+-0.08. The planetary companion has a mass of 0.292+-0.018 Mjup,
and radius of 1.132+-0.072 Rjup yielding a mean density of 0.25+-0.04 g cm-3.
The radial velocity residuals for HAT-P-19 exhibit a linear trend in time,
which indicates the presence of a third body in the system. Comparing these
observations with theoretical models, we find that HAT-P-18b and HAT-P-19b are
each consistent with a hydrogen-helium dominated gas giant planet with
negligible core mass. HAT-P-18b and HAT-P-19b join HAT-P-12b and WASP-21b in an
emerging group of low-density Saturn-mass planets, with negligible inferred
core masses. However, unlike HAT-P-12b and WASP-21b, both HAT-P-18b and
HAT-P-19b orbit stars with super-solar metallicity. This calls into question
the heretofore suggestive correlation between the inferred core mass and host
star metallicity for Saturn-mass planets.Comment: 18 pages, 11 figures, 9 tables. Replaced with version accepted for
publication in Ap
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