Excessive mobilization of body reserves during the transition from pregnancy to lactation imposes a risk for metabolic diseases on dairy cows. We aimed to establish an experimental model for high v. normal mobilization and herein characterized performance, metabolic and endocrine changes from 7 weeks antepartum (a.p.) to 12 weeks postpartum (p.p.). Fifteen weeks a.p., 38 pregnant multiparous Holstein cows were allocated to two groups that were fed differently to reach either high or normal body condition scores (HBCS: 7.2 NEL MJ/kg dry matter (DM); NBCS: 6.8 NEL MJ/kg DM) at dry-off. Allocation was also based on differences in body condition score (BCS) in the previous and the ongoing lactation that was further promoted by feeding to reach the targeted BCS and back fat thickness (BFT) at dry-off (HBCS: >3.75 and >1.4 cm; NBCS: <3.5 and <1.2 cm). Thereafter, both groups were fed identical diets. Blood samples were drawn weekly from 7 weeks a.p. to 12 weeks p.p. to assess the serum concentrations of metabolites and hormones. The HBCS cows had greater BCS, BFT and BW than the NBCS cows throughout the study and lost more than twice as much BFT during the first 7 weeks p.p. compared with NCBS. Milk yield and composition were not different between groups, except that lactose concentrations were greater in NBSC than in HBCS. Feed intake was also greater in NBCS, and NBCS also reached a positive energy balance earlier than HBCS. The greater reduction in body mass in HBCS was accompanied by greater concentrations of non-esterified fatty acids, and β-hydroxybutyrate in serum after calving than in NBCS, indicating increased lipomobilization and ketogenesis. The mean concentrations of insulin across all time-points were greater in HBCS than in NBCS. In both groups, insulin and IGF-1 concentrations were lower p.p than in a.p. Greater free thyroxine (fT4) concentrations and a lower free 3-3′-5-triiodothyronine (fT3)/fT4 ratio were observed in HBCS than in NBCS a.p., whereas p.p. fT3/fT4 ratio followed a reverse pattern. The variables indicative for oxidative status had characteristic time courses; group differences were limited to greater plasma ferric reducing ability values in NBSC. The results demonstrate that the combination of pre-selection according to BCS and differential feeding before dry-off to promote the difference was successful in obtaining cows that differ in the intensity of mobilizing body reserves. The HBCS cows were metabolically challenged due to intense mobilization of body fat, associated with reduced early lactation dry matter intake and compromised antioxidative capacity.

The various relativistic effects occuring in VLBI measurements are discussed. A concrete example showing the influence of the gravitational delay due to the Sun upon the delay residuals from fit in a Mark III geodetic VLBI experiment is given. It is argued that regular geodetic VLBI observations might provide the best test of Einstein's theory of gravity on the post-Newtonian level in the near future.

Two series of UT1 data determined by VLBI within Project IRIS at 5 day intervals respectively on a daily basis have been subjected to an iterative spectral analysis. Various significant oscillations with periods less than two months could be detected in the IRIS UT1 data. Most of the periods between 18 and 63 days obviously correspond to short-period variations in global atmospheric data. The other significant variations with periods shorter than 35 days can be clearly identified as being due to the influence of zonal tides on the rotation of the earth. The results of the spectral analysis are compared with the theoretical periods and phases and with the amplitudes given by Yoder et al. (1981). The spectral analysis reveals very clearly the monthly (27.6d) and the fortnightly (13.7d) terms and also the smaller variations at 14.77 days and 9.13 days. A similar analysis of 8 subsets, each with two months of the daily UT1 determinations, indicates that the small 7.10 day term can already be extracted from the VLBI observations.

The first high accuracy VLBI measurements with the Hartebeesthoek Radio Astronomy Observatory (HartRAO) at the southern end of the African tectonic plate were made possible at the beginning of 1986 through the loan of a MARK III DAT to HartRAO by the US National Geodetic Survey. Six twenty-four hour experiments spread over thirty-three days were used to precisely determine the HartRAO station position and to measure baseline lengths to Europe and North America. Interleaved between these multi-station experiments, a single baseline from Wettzell to HartRAO was used for two hours on a daily basis in order to measure pole positions. The formal errors of the x and y pole component determinations for each day are about ±2 mas and ±1 mas respectively, but an offset of about 6 mas from the IRIS values remains to be investigated.

The geodetic IRIS-network is a transatlantic 5-station VLBI-array dedicated to monitor variations of the earth's rotation (e.g. Carter et al., 1985). In a 5 day cycle 14 extragalactic radio sources are observed in regular intervals, covering a GST-range of up to 24 hours, using the MkIII-system in Mode C at 3.6cm (X-band) and 13cm (S-band) wavelength. As this database provides a great potential to monitor source structures and their changes with mas-resolution (the sample contains at least 7 “superluminals”), we have initiated a project to obtain radio maps at both frequencies and to determine, how accurate physical parameters like component flux densities and separations can be measured. Early results are published in Schalinski (1985) and Schalinski et al. (1986). In addition to astrophysical applications, we investigate the influence of structure phases on phase- and group-delay corrections (s. Campbell et al., this vol.).

We developed a structure algorithm for the computation of phase- and group delay corrections to geodetic VLBI observations. For some of the sources, i.e. 3C454.3, 3C273B and 3C345 the corrections are in the range of several hundred picosecs of group delay.

Evidence is found that in IRIS experiments the gravitational time delay due to the gravitational field of the Earth can be seen. Influences of this time delay upon baseline determinations are discussed.

In this paper we study a special class of size dependent branching processes. We assume that for some positive integer K as long as the population size does not exceed level K, the process evolves as a discrete-time supercritical branching process, and when the population size exceeds level K, it evolves as a subcritical or critical branching process. It is shown that this process does die out in finite time T. The question of when the mean value E(T) is finite or infinite is also addressed.

Two long time series of polar motion were analysed with respect to a linear drift, decadal variations, Chandler wobble and annual wobble: the C01 series published by the International Earth Rotation Service (IERS) and the pole series which J. Vondrák, obtained by re-analysis of the classical astronomical observations using the HIPPARCOS reference frame (1899.7–1992.0). By a least-squares fit the linear drift of the pole, usually called ‘secular polar motion,’ was determined to 3.31 milliarcseconds/year (mas/yr) toward 76.1° West longitude. For this fit the a priori correlations within each pair of pole coordinates were taken into account, and the weighting function was calculated by estimation of empirical variance components. The decadal variations of the pole path were determined by Fourier analysis. Using a sliding window analysis, the variability of the periods, the amplitudes and the phases of the Chandler wobble and annual wobble was investigated. The variances of the results and the number of iterations needed to get a convergence in the nonlinear approach show that the new time series by Vondrák is more homogeneous and consistent than the IERS C01 series.

Sub-seasonal variations and especially sub-seasonal oscillations with periods of about 120, 60, 50, 40 days in polar motion and of about 120, 60–90, and 50 days in LOD are presented. Variations of amplitudes of these sub-seasonal oscillations of polar motion are shown. Maxima of these amplitudes are of the order of 2–4 mas. These oscillations are elliptical ones. The correlation coefficients between geodetic and atmospheric excitation functions in this range of the spectrum are variable and have annual variations. Maxima of correlation coefficients are of the order of 0.6–0.8.

Modern geodetic VLBI experiments provide very accurate results in polar motion and UT1–UTC with a temporal resolution of 3–7 minutes. Several irregular, quasi-periodic variations were found. In many UT1–UTC data sets, oscillations with periods around 8 hours and between 5 and 7 hours can be seen.

The goal of the division is to address the scientific issues that were developed at the 2009 IAU General Assembly in Rio de Janeiro. These are:

• •Astronomical constants
• —Gaussian gravitational constant, Astronomical Unit, GMSun, geodesic precession-nutation
• •Astronomical software
• •Solar System Ephemerides
• —Pulsar research
• —Comparison of dynamical reference frames
• •Future Optical Reference Frame
• •Future Radio Reference Frame
• •Exoplanets
• —Detection
• —Dynamics
• •Predictions of Earth orientation
• •Units of measurements for astronomical quantities in relativistic context
• •Astronomical units in the relativistic framework
• •Time-dependent ecliptic in the GCRS
• •Asteroid masses
• •Review of space missions
• •Detection of gravitational waves
• •VLBI on the Moon
• •Real time electronic access to UT1-UTC

We have examined the effects of isothermal annealing, at a variety of temperatures, and directional annealing, under a range of conditions, on both primary recrystallization and secondary recrystallization in 90% cold-rolled 99.5% nickel of two different textures. The initial texture is shown to influence the rolling texture and, hence, the results of subsequent annealing. It was found that one alloy showed a cube texture after primary recrystallization, underwent abnormal grain growth upon annealing at high temperatures, and could be directionally (secondary) recrystallized to give large columnar grains. In contrast, the other alloy produce a weak cube texture after primary recrystallization, showed only normal grain growth upon annealing at higher temperatures, and could not be directionally annealed to produce columnar grains. The implications of these results are discussed for producing columnar grains.

Atomistic simulations have provided unprecedented insight into the structural and mechanical properties of nanocrystalline materials, highlighting the role of the non-equilibrium grain boundary structure in both inter- and intra-grains deformation processes. One of the most important results is the capability of the nanosized grain boundary to act as a source and sink for dislocations. However the extrapolation of this knowledge to the experimental regime requires a clear understanding of the temporal and spatial scales of the modelling technique and a detailed structural characterisation of the simulated samples. In this contribution some of the synergies that can be develo ped between atomistic simulations and experiments for this research field are briefly discussed by means of some typical examples.

From the reported experience, primary nanocrystallization in amorphous Al alloys involves transient kinetic behavior that is sensitive to the initial as-quenched structural arrangements. In order to examine the precursor effects, systematic studies outlining the evolving growth kinetics of primary aluminum nanocrystals (nc) during pre-crystallization annealing treatments, and investigations on the microstructure refining effect of specific alloying substitutions represent new approaches for an analysis of primary phase crystallization kinetics. In Al88Ni8Sm4 melt-spun ribbon (MSR), incremental substitutions of Cu for Ni (0 − 1at%) affect the thermal stability of the material (crystallization onset shifts to lower temperature) and refine the size of the primary phase nanocrystals. However, continuous heating calorimetry measurements indicate that the primary crystallization enthalpy remains approximately constant with increased Cu substitution. From a structural analysis standpoint, quantitative microstructure examinations applied in parallel with calorimetry measurements have been employed to characterize the as-quenched volume of MSR samples. The increased primary Al nanocrystal particle density with Cu substitution reflects the modification of local structural arrangements, necessitating an understanding of the local structure of the as-quenched sample in order to develop a description of primary phase nanocrystal growth kinetics.

Mechanical alloying techniques, which use plastic deformation to effect structural changes, are commonly used to prepare nanostructured metals with exemplary mechanical properties. When these nanostructured metals are subjected to further straining fully amorphous alloys can result, but there is little understanding of the atomic-scale mechanisms behind this amorphization. In the present work, we explore the final stages of such a mechanical alloying process via molecular simulations. Initial Cu-Zr nanolaminates are sequentially strained and consolidated, and the amorphization process is followed explicitly. The results are in qualitative agreement with existing experimental data, and provide insight into experimentally inaccessible features of the structural evolution.

In this paper recent results by Weiner [10] on Mn := max{Z 0, · ··, Zn } are strengthened and generalized, where (Zn ) n is a critical Galton–Watson branching process with finite and positive offspring variance and Z 0 ≡ 1. It is shown that Explicit asymptotic bounds are given for with . If (Zn ) n has a linear fractional offspring distribution, it can be embedded in a critical birth and death process (Ẑ t ) t . Using martingale methods one obtains thereof.

These results generalize to the case Z 0 ≡ k.

Let be a supercritical Bellman-Harris process with finite offspring mean. Cohn [17] has shown that there always exist constants Ct such that lim t→∞ Zt /Ct = W almost surely for some non-degenerate random variable W. In this paper we give an alternative proof, based on the study of (Zt ) as a point process. Our methods are to some extent analytical and parallel Seneta's [18] and Heyde's [11] approaches in the case of the Galton–Watson process. We further identify Ct as 1/(–log Ft (–1)(γ)), where Ft (γ) = E(γ z t), i.e. the norming constants found by Seneta [18] for the Galton–Watson process, apply also to the Bellman-Harris process. Finally we derive a weak law of large numbers for W, prove that W is continuous on (0,∞) and show that W has [0,∞) as its support.

We show for a certain class of Galton–Watson branching processes in varying environments (Zn ) n that moments of the maximum random variable sup n Zn/Cn exist if and only if the same moments of lim nZn/Cn exist, where Cn is a sequence of suitable constants.

We show that the Harris-Sevast'yanov transformation for supercritical Galton-Watson processes with positive extinction probability q can be modified in such a way that the extinction probability of the new process takes any value between 0 and q. We give a probabilistic interpretation for the new process. This note is closely related to Athreya and Ney (1972), Chapter 1.12.

We give necessary and sufficient conditions for in terms of , where Sn is the sum of n i.i.d. random variables with values in]0, ∞[, and A ≧ 0. We use these results to give a probabilistic proof of the ‘explosion criterion' for continuous-time Markov branching processes, which is usually shown analytically.