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551.
The estimation of genetic parameters has played an important role in animal selective breeding for growth traits.Recently studies show that molecular markers can be incorporated into genetic evaluations. In order to improve the performance of an incomplete pedigree(i.e, only parents are known) in the genetic evaluations, 12 microsatellite markers have been applied in the estimation of the genetic parameters for body weight in a farmed population(n=1 890) of juvenile turbot(Scophthalmus maximus L.). A new relatedness called parental molecular relatedness(PMR) is estimated based on results of genotyping of 48 parents(31 males, 17 females) with microsatellites markers. The feasibility of PMR in estimation of genetic parameters is verified by comparison with pedigree related(PR) which is obtained from a complete pedigree. The results demonstrate that a high correlation(0.872) between them is found. Heritabilities are estimated using the PMR(0.52±0.13) and PR(0.55±0.22) with the same animal model. A cross-validation shows that the predictive abilities of models using the PMR and the PR are identical(0.81). From that, a conclusion can be made that PMR and PR predicted genetic values equally well in a population of juvenile turbot. Therefore PMR can be applied as an alternative of the PR when only parents are known. However, for a better performance, more markers and more families should be included in a further study.  相似文献   
552.
The objective of this study is to provide insights into the REE and Y behavior during garnet porphyroblast formation in staurolite-bearing schists as a constituent of Late Paleoproterozoic metapelites of the Ladoga Complex. The MnNCKFMASH P–T pseudosection for a single sample and Grt–Bt thermometry indicate that the garnet core grew at 520°C and under 7.0–7.2 kbar in the Grt–Bt–Pl–Chl–Ms–Zo field, whereas the garnet rim was equilibrated at 590–600°C and under 3.5–4.0 kbar. The measured zoning profiles are strongly depleted in REE + Y in the garnet core containing high Mn and Ca concentrations. The intermediate zone of garnet is enriched in La, Ce, Pr, and Nd (inner LREE + Nd annulus), as well as in Dy, Er, Yb, Lu, and Y (outer HREE + Y + Dy annulus). According to pseudosection analysis, these peaks were probably produced owing to breakdown of epidote-group minerals (allanite, REE-rich epidote) at T < 535°C and P > 6.5 kbar. Towards the rim, the HREE + Y contents gradually decrease, whereas MREE (Sm, Eu, Gd) display an inverse trend. The rim also exhibits a negative Eu anomaly. The former tendency reflects an increase in temperature during garnet crystallization and partitioning of elements between garnet and monazite. It is thought that the latter is linked to oppositely directed change in garnet-monazite partition coefficients for HREE and MREE with increasing temperature.  相似文献   
553.
Several types of both magmatic and metamorphic spinels have been found in Archean komatiites of the Sovdozero and Kostomuksha greenstone belts in the eastern part of the Fennoscandian Shield. Scanning electron microscopy and Raman spectroscopy revealed relics of cores of primary magmatic chrome-spinels with high Cr and Al contents. In the Sovdozero structure, the relics are better retained than those in the Kostomuksha structure, which is caused by a different degree of metamorphic transformation. The comparable 100 · Cr/(Al + Cr) values of spinel cores from Sovdozero and Kostomuksha reflect similar conditions of partitional melting in the mantle. These data agree with the fact that both komatiite complexes belong to the Al-undepleted petrogenic type. Wide variations in the Cr and Al contents in primary chrome-spinel cores together with a constant Mg/(Fe2+ + Mg) ratio correspond to low oxygen fugacity during magma crystallization. In general, the composition of these primary chrome-spinels is similar to that of accessory phases in peridotites from suprasubduction zones and agrees with hypothesis of komatiite complex formation in back-arc basins.  相似文献   
554.
The energy spectra and relative abundances of 3He, 4He, C, O, and Fe ions with energies of ~0.04–2 MeV/nucleon are studied using data from the ULEIS instrument on board the ACE spacecraft obtained during quiescent periods in 2006–2012. During the unique, prolonged minimum between cycles 23 and 24, 35 quiescent periods were distnguished, during which solar-wind flows from near-equatorial coronal holes (CHs) were detected. It is shown that the C/O and Fe/O ratios for suprathermal ions correspond to the relative abundances of the corresponding thermal ions in the fast and slow (Maxwellian) solar wind (SWICS/ACE), while the 4He/O ratio exceeds the corresponding ratio in the solar wind by a factor of two. The intensities of the 3He, 4He, C, O, and Fe suprathermal ions in outflows from CHs grow with the speed of the solar wind. This indicates that, in periods ofminimumsolar activity, suprathermal ions from CHs represent a high-temperature “tail” of the solar wind. An additional flux of suprathermal helium ions may also be contributed by other external sources.  相似文献   
555.
Multi-wavelength observations and magnetic-field data for the solar flare of May 10, 2012 (04: 18 UT) are analyzed. A sign change in the line-of-sight magnetic field in the umbra of a small spot has been detected. This is at least partly associated with the emergence of a new magnetic field. A hard X-ray flare was recorded at almost the same time, and a “sunquake” was generated by the impact of the disturbance in the range of energy release on the photosphere. A sigmoid flare was recorded at the beginning of the event, but did not spread, as it usually does, along the polarity inversion (neutral) line. SDO/HMI full vectormagnetic-fieldmeasurements are used to extrapolate the magnetic field of AR 11476 into the corona, and to derive the distribution of vertical currents jz in the photosphere. The relationship between the distribution of currents in the active region and the occurrence of flares is quite complex. The expected “ideal” behavior of the current system before and after the flare (e.g., described by Sharykin and Kosovichev) is observed only in the sigmoid region. The results obtained are compared with observations of two other flares recorded in this active region on the same day, one similar to the discussed flare and the other different. The results confirm that the formation and eruption of large-scale magnetic flux ropes in sigmoid flares is associated with shear motions in the photosphere, the emergence of twisted magnetic tubes, and the subsequent development of the torus instability.  相似文献   
556.
557.
New data on the mineral composition of the Ozernoye meteorite, found in the Kurgan region in 1983, are presented. It has been found that that the meteorite’s matter is composed of olivine (chrysolite), orthopyroxene (bronzite), clinopyroxene (augite), maskelynite, chromite, ilmenite, metals Fe and Ni (kamasite, taenite), sulfides (troilite, pentlandite), chlorapatite, and merrillite. Augite, taenite, pentlandite, and merrillite were identified in the Ozernoye meteorite for the first time. The chemical compositions are given for all these minerals. The meteorite itself is an ordinary chondrite stone belonging to petrological type L5.  相似文献   
558.
The magnetic-field structure in regions of stationary, planar accretion disks around active galactic nuclei where general-relativistic effects can be neglected (from 10 to 200 gravitational radii) is considered. It is assumed that the magnetic field in the outer edges of the disk, which forms in the magnetosphere of the central black hole during the creation of the relativisitic jets, corresponds to the field of a magnetic dipole perpendicular to the plane of the disk. In this case, the azimuthal field component Bφ in the disk arises due to the presence of the radial field Bρ and the azimuthal velocity component Uφ. The value of the magnetic field at the inner radius of the disk is taken to correspond to the solution of the induction equation in a diffusion approximation. Numerical solutions of the induction equation are given for a number of cases.  相似文献   
559.
Analysis of petrochemical and geochemical information of the same levels, which characterize rocks and primary melt inclusions in olivines of heterochronic meimechite–picrite associations in Siberia (Maimecha–Kotui province), Primorye (Sikhote–Alin), and Kamchatka demonstrated that, besides the similar appearance and identical structural patterns, they are considerably discrepant in the concentration and distribution of incompatible and rare earth elements. Those differences are also observed for the compositions and evolutionary trends of parental high-temperature magnesium-rich melts. This, in turn, was assumed to be a consequence of a variable degree of melting of the mantle protoliths in the mentioned regions, which is supported by geochemical modeling.  相似文献   
560.
A new series of yearly-mean relative sunspot numbers SN 2 that has been extrapolated into the past (to 1610) is presented. The Kislovodsk series with the scale factor b = 1.0094 ± 0.0059 represents a reasonable continuation of the mean-monthly and mean-yearly total sunspot areas of the Greenwich series after 1976. The second maximum of the 24th solar-activity cycle was not anomalously low, and was no lower than 6 of the past 13 cycles. A series A 2 of values for the total sunspot area in 1610–2015 has been constructed, and is complementary to new versions of the series of the relative number of sunspots SN 2 and the number of sunspot groups GN 2. When needed, this series can be reduced to yield a quantity having a clear physical meaning—the spot absolute magnetic flux Φ Σ(t)[Mx] = 2.16 × 1019 A(t) [mvh]. The maximum sunspot area during the Maunder minimum is much higher in the new series compared to the previous version. This at least partially supports the validity of arguments that cast doubt on the anomalously low ampltude of the solar cycles during the Maunder minimum that has been assumed by many researchers earlier.  相似文献   
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