bluuebunny/crossref_metadata_2025 huggingface dataset:
Analytical Approximations of Long-Exposure Point Spread Functions and their Use
Authors: Bendinelli O. , Parmeggiani G. , Zavatti F.
Published: June 2019

The observed light distribution in long exposure star images (PSF) may be fitted equally well by a variety of models. But dealing with undersainpled star images, only the use of the multi-Gaussian model allows the correct model parameters estimation, taking into account integration on pixel surface, image off-centering and background behaviour. It is also shown that the convolution of a spherical source with the multi-Gaussian and Moffat’s models gives in practice the same result.
Commissions 10 and 12 Systematic Observations of the Sun
Authors: Pecker Jean-Claude , Wilson Peter
Published: June 2019

This meeting was dedicated to Helen DODSON-PRINCE who has contributed so much to the field. Unfortunately, she was unable to attend the General Assembly, but a telegram has been approved by acclamations and sent to her, expressing to our colleague and friend the deep admiration and the friendly feelings of the solar community, as gathered in Baltimore.
The Microwave Background Radiation: Recent Advances and New Problems
Authors: de Zotti G. , Toffolatti L.
Published: June 2019

The substantially improved intensity measurements at wavelengths longward of the intensity peak of the microwave background are fully consistent with a Planck spectrum. The most precise data disagree with non-relativistic comptonization models for the large submillimeter excess observed by the Nagoya-Berkeley collaboration. The interpretation of such excess as dust emission at high redshifts also faces severe difficulties. Reported anisotropies on scales of several degrees and of tens of arcsec may be contributed, at least in part, by discrete sources. Just because the best experiments at cm wavelengths nave already got close to the source confusion limit, they also provide interesting information on the large scale distribution of radio sources. Polarimetry may be decisive in clarifying the origin of observed fluctuations.
Relativistic Aspects of Reference Systems and Time Scales
Authors: Brumberg V.A.
Published: June 2019

Mindful of the fact that any time and space coordinates of General Relativity Theory (GRT) are not, in general, physically meaningful and measurable quantities, one may choose between three possibilities in applying GRT to ephemeris astronomy:

1)

avoid coordinates completely, i.e., construct coordinate-independent theories of light propagation and solar system body motion involving the removal of all coordinate-dependent quantities from the present system of astronomical constants;

2)

use any coordinate system to describe observational procedures and to solve dynamics problems, provided that one and the same coordinates be used for both the kinematics and dynamics of a specific problem;

3)

adopt IAU recommendations specifying reference systems and time scales to be used in ephemeris astronomy.
X-ray Morphology of Clusters of Galaxies
Authors: Böhringer H. , Schwarz R.A. , Briel U.G. , Ebeling H. , Voges W.
Published: June 2019

The ROSAT observatory with its high spatial resolution X-ray telescope is an ideal instrument for the study of clusters of galaxies. In the first part of the mission an All Sky X-ray Survey was conducted with ROSAT. Here we present first results of observations of Virgo, Perseus and some other clusters of galaxies from the All Sky Survey. These data illustrate the capabilities of the ROSAT observatory for studies of the morphological structure and physical properties of galaxy clusters.
Opening Remarks
Authors: Partridge R. B.
Published: June 2019

The following papers formed a Joint Discussion sponsored by Commissions 40, 44, 47 and 48 of the International Astronomical Union. The topic was Cosmic Backgrounds. The plural “backgrounds” is important. Speakers considered electromagnetic radiation fields ranging from radio wavelengths to X-rays. Because other sessions at this General Assembly treated higher energy backgrounds, in particular the X-ray region, emphasis in this Joint Discussion was on radio and infrared backgrounds. In addition to the wide range of wavelengths covered, the session also dealt with a wide range of models for various backgrounds. For instance, at some wavelengths (e.g., λ ~ 1 cm) the background is truly a background, generated at very high redshifts—in this case a thermal radiation field at ~ 3 K. At other wavelengths (e.g., in the X-ray region) the “background” may consist in whole or in part of the summed emission from many unresolved or subliminal sources.
Observation and Interpretation of the Cosmic Microwave Background Spectrum
Authors: Mather J. C.
Published: June 2019

Recent precise observations of the microwave and submillimeter cosmic background radiation are summarized, including rocket experiments, the FIRAS (Far InfraRed Absolute Spectrophotometer) on the COBE, CN results, and microwave measurements. Theoretical implications are summarized.
Observation of the Cosmic Microwave Background Anisotropy
Authors: Smoot George F.
Published: June 2019

Recent precise observations of the cosmic microwave background (CMB) isotopy and experiments in progress are summarized. The current measurements on all angular scales are approaching sensitivities of the order of ΔT/T ≈ 10-5. Nearly all experiments are observing positive detections. Most assume the detection to be due to galactic emission or other foregrounds or systematics and not due to primordial anisotropies in the CMB. The context and significance of these observations are discussed.
The Microwave Background Radiation: An Alternative View
Authors: Narlikar Jayant V.
Published: June 2019

Why do we need to think about any alternatives when the primordial interpretation of the microwave background radiation (MBR) has been accepted by so many for so long? The answer is that the primordial interpretation, in spite of its successes has manifest shortcomings in spite of attempts to remove them by so many for so long. To mention a few:

a)

Why is the MBR temperature 2.7 K? The value is taken as a parameter in all early universe calculations; it is not predicted by the hot big bang theory with or without inflation.

b)

There are other astrophysical processes of comparable energy density and other radiation backgrounds that have no primordial origin; why should MBR alone stand out as the odd one out just at this epoch?

c)

Why are there no signatures of structure formation on the MBR; why is it so smooth?

d)

The hot big bang model relates to the universe in the first three minutes while the MBR is observed in the more recent past; are we not making too long a jump across from the one to the other?
Diagnostics of Models for Cosmic Structure Formation
Authors: Fukugita Masataka
Published: June 2019

In this talk I shall discuss two topics related to modeling of cosmic structure formation. In the first part I shall briefly review the problem of cosmologica! parameters, which are crucial for any of model calculations. An emphasis is made on whether we need a non-zero cosmologica! constant. In the latter part cosmic microwave background (CMB) anisotropics are discussed as a probe of the models for cosmic structure formation.
From Planetoids to Planets
Authors: Barge P. , Pellat R.
Published: June 2019

A common origin of the sun and the planets from the collapse of interstellar gas is now widely accepted. Regardless of how stars form, which is considered as the previous step of the whole story, the starting point is a flattened rotating cloud containing a mixture of dusts and gas (the so called Kant-Laplace Nebula). On the other hand the observations of young solar-mass stars show with increasing evidence that the gas is dispersed away on a time scale less than 107 years and this provides us with a clear time constraint for model building since the formation of the giant gaseous planets have to take place on a shorter time scale.
Circumstellar Disks and Star Formation
Authors: Hartmann L. , Gomez M. , Kenyon S.J.
Published: June 2019

Results from the IRAS satellite showed that many pre-main sequence stars exhibited unexpectedly large fluxes in the infrared spectral region. Several studies have shown that the simplest and most satisfying explanation of this excess emission is that it arises in optically-thick, dusty, circumstellar disks (Rucinski 1985; Adams, Lada, and Shu 1987, 1988; Kenyon and Hartmann 1987; Bertout, Basri, and Bouvier 1988; Basri and Bertout 1989). The masses of these disks are estimated to range between 10-3M⊙ to 1M⊙ (Beckwith et al. 1990; Adams et al. 1990), large enough that disk accretion may have a significant effect on the evolution of the central star. Indeed, Mercer-Smith, Cameron, and Epstein (1984) suggested that stars are essentially completely accreted from disks, rather than formed from quasi-spherical accretion (Stabler 1983, 1988).
Solar System Objects in the HIPPARCOS Programme
Authors: Bec-Borsenberger A.
Published: June 2019

Forty eight minor planets and two planetary satellites have been retained in the Hipparcos programme. The observations of minor planets will be used to try to determine the dynamical equinox and the rotation of the Hipparcos reference system (S. Söderhjelm and Lindegren, 1982); they can be also used to determine some physical properties of minor planets. As for the observations of planetary satellites, they will allow to obtain accurate ephemendes of these objects and to improve those of the primary planets. The inclusion of minor planets and satellites in the observing programme raises very specific problems: owing to their motion, positions of these objects are given in the Input Catalogue using ephemerides; preparatory astrometric work needed for improving these ephemerides (ground-based observations and improvement of orbital elements) has been described in Bec-Borsenberger (1989, 1991a). To be sure that the ephemerides are sufficient to get the 1 arcsecond predictability needed for Hipparcos, a reduced programme of ground-based observations will last all along the Hipparcos campaign (with the automatic meridian circles of Bordeaux and La Palma observatories). Presently, an annual update is adequate in order to ensure this precision. The improved orbital elements and predicted ephemerides for years 1991 and 1992 are published (Bec-Borsenberger, 1990, 1991b): the residuals obtained from the last set of improved elements with the meridian observations made for the Hipparcos programme givermsin right ascension and declination between 0.19 and 0.38 arcsecond for all Hipparcos minor planets. Since the launch of Hipparcos, the two satellites have been observed and about a third of the minor planets of the programme have been found; the previsions allow to hope to observe this year about ten more minor planets.
On-Ground Attitude Determination in the HIPPARCOS Mission
Authors: Donati F. , Canuto E. , Falin J.L. , Froeschlè M. , Kovalevsky J.
Published: June 2019

An accurate on-ground reconstitution of the satellite three-axes attitude from the downlinked star mapper photon counts is an essential factor in the final accuracy of the Hipparcos Astrometric Catalogue. The reconstitution method developed by the FAST Consortium and currently on use to process Hipparcos data is the concern of this paper. After on outline of the main reconstitution models and algorithms, an accuracy assessment of the estimates, attitude and star coordinates, coming out from the first year data reduction, is presented; the assessment shows that attitude root mean square errors are already around the mission target of 0.1 arcseconds.
Tycho Astrometry and Photometry
Authors: Høg E.
Published: June 2019

In the Tycho project astrometric and photometric data of about 1 000 000 stars to a limit of B = 12 mag will be derived. The brightest 500 000 stars will obtain magnitudes in two colours BT and VT, the fainter 500 000 usually only one broad-band magnitude T. There is confidence that an accuracy will be achieved about 0.03 arcsec for positions and 0.03 mag for magnitudes, at B = 10.5 mag. The results are obtained by appropriate treatment of the continuous data records generated by the Hipparcos satellite’s star mapper (which provide simultaneous measurements in two spectral channels), based on predicted star transits using its own ‘Tycho Input Catalogue’. The data treatment is carried out by the Tycho Data Analysis Consortium (TDAC), using calibration and satellite attitude information from the two Hipparcos data reduction consortia. An overview of the data reductions is given. Raw observation data and their numerical treatment are described. This assessment is based on a small data set, i.e. 12 weeks spread over the first 8 months of the Tycho ‘revised mission’ where the satellite is in the elliptical transfer orbit, instead of the intended geostationary orbit.
Double Star Recognition
Authors: Frœschle M. , Mignard F. , Falin J.L.
Published: June 2019

Hipparcos observations provide a wealthy source of discovery of new double and multiple stars. We have developed adequate procedures to recognize in the signal parameters the multiplicity of the stellar source passing through the Hipparcos field of view. These procedures are outlined together with the design of the statistical tests employed. Sampling on real data indicates that about 6000 new double stars will be detected at the mission completion.
Radial Velocities for the Stars of the HIPPARCOS Mission
Authors: Mayor Michel , Gerbaldi Michèle , Grenier Suzanne , Levato Hugo
Published: June 2019

A large fraction if not all of the programmes related to the study of the galactic structure, its kinematics and chemical evolution will require the knowledge of the third component of the velocity: the stellar radial velocity. But we will also need the radial velocity to be able to determine the true distribution of masses in the solar neighborhood (corrected by the crossing time of the stars in the sampled sphere). The radial velocity will allow the determination of the statistical parallax for a sample of stars lying beyond 100 parsec. At the very beginning of the development of the Hipparcos space mission, the very need for ground-based, complementary measurements has been recognized. However, in spite of the existence of new kinds of techniques or detectors, the task to provide radial velocities for the somewhat 118’000 stars of the Hipparcos Input Catalogue is quite enormous. All presently published stellar radial velocities determined since the beginning of this century represent at the most 20 to 25% of the total number of stars to be measured!
A Comparison of the Southern Optical and Radio Astrometric Reference Frames
Authors: White Graeme L. , Jauncey D.L. , Reynolds J.E. , Lestrade J.-F. , Malin D.F. , Russell J. , Johnston K.J. , Vegt C. de , Nicolson G.
Published: June 2019

A comparison of accurate optical and radio positions is presented for 25 southern compact radio objects. There is a systematic “S” shaped trend indicating a zonal bias in the Perth 70 optical catalogue.
Proposal for a Second HIPPARCOS
Authors: Høg E. , Chubey M.S.
Published: June 2019

An improved astrometric space mission similar to Hipparcos is proposed for launch ten years after the present Hipparcos. The new mission should provide positions, parallaxes and annual proper motions with an accuracy about one milli-arcsecond for some 400 000 stars. The positions from the two missions would give proper motions for the 120 000 common stars with an accuracy about 0.2 milli-arcsecond per year, ten times less than expected for the first mission. The improvements of the satellite relate e.g. to: larger telescope aperture, smooth attitude motion, enhanced star mapper for four-colour observations (B V U R) of two million stars. The proposal resulted from discussions with members of the Pulkovo Observatory and the Hipparcos Science Team, and it is being considered by the Mission Control Centre, Moscow.
GHRS Observations of the Bp Star, chi Lupi
Authors: Leckrone David S.
Published: June 2019

High resolution, high S/N ultraviolet observations of the ultra-sharp-lined Bp star chi Lupi, obtained with the Goddard High Resolution Spectrograph, reveal an unprecedented level of spectroscopic detail. Spectral synthesis of the Hg II λ1942 resonance line confirms the extreme isotope abundance anomaly of mercury in this star. The data also provide the first positive detections of Ru II and Zr III, and tentative detections of As I and Ge II.
The Hubble Space Telescope Servicing Mission
Authors: Boggess Albert
Published: June 2019

This paper will not review in any detail the performance problems that have been discovered with the Hubble Space Telescope (HST) after it was placed into orbit on April 25, 1990, but rather it will concentrate on the efforts currently under way to conduct a servicing mission late in 1993 in order to restore both the telescope and the spacecraft to their expected capabilities. The detailed planning for this mission will intentionally be left flexible as long as possible to be able to respond to future changes in spacecraft performance. The descriptions below reflect the state of the hardware and planning as of November, 1991. These developments include four major types of spacecraft hardware, plus the carriers, tools and the plans for the servicing mission itself. In addition, some other hardware items are being considered as desirable additions, if schedules and budgets permit.
Automated Telescopes for Photometry and Imaging: Performance and Results with Infrared Arrays
Authors: Mclean Ian S.
Published: June 2019

An edited review of the presentations given at Joint Commission Meeting II during the 21st General Assembly of the IAU is presented.
Summary of Available and Planned Atomic Databases
Authors: Martin W. C.
Published: June 2019

Several of the larger and more inclusive atomic data centers and databases useful for space astronomy are briefly described here. Bibliographic reports on atomic and molecular data useful for astronomy are given in Ref. [1].
Atomic and Molecular Data Needed for Analysis of Infrared Spectra from ISO and Sirtf
Authors: Bernath P.F.
Published: June 2019

The satellites ISO and SIRTF are cryogenically-cooled infrared observatories. These telescopes will provide a tremendous increase in sensitivity and will, therefore, require new laboratory data to support their missions. A survey of some of the necessary atomic and moelcular data is presented.
Atomic Data Needed for Fuv Astronomy with Hut and Fuse
Authors: Linsky Jeffrey L.
Published: June 2019

The important atomic and molecular data needed by astrophysicists who analyze far ultraviolet spectra include accurate wavelengths, ocsillator strengths, molecular data for six molecules, and especially electron collisional exciatation cross sections.
AGB Star Models
Authors: Hollowell David
Published: June 2019

Asymptotic giant branch star models are reviewed in relation to luminosity observations and chemical abundance observations of these stars.
X-Ray Observations of Stars: First Results from Rosat
Authors: Schmitt J.H.M.M.
Published: June 2019

At the time of writing (i.e., September 1991), the ROSAT all-sky survey has been completed and almost the entire sky has been scanned with an imaging X-ray telescope down to a limiting flux of approximately 2 10−13erg/s/cm2 in the pass band 0.1 — 2.0 keV; in regions of deeper exposures near the poles of the ecliptic considerably fainter flux limits have been achieved. While the processing and analysis of this huge body of data is still in progress and hence final results on the number of detected sources and their distribution in flux are not yet available, the total number of detected X-ray sources will be around 60 000. Preliminary results from optical identifications of selected fields show that about one quarter of the X-ray sources discovered at high galactic latitudes come from by comparison nearby stellar sources (Fleming 1991), while at lower galactic latitudes up to one half of the detected X-ray sources are of stellar origin; in areas occupied by star forming regions (for example, Orion) or open clusters (for example, Hyades or Pleiades) a large number of the detected X-ray sources can be identified with young stars, yielding up to 80 percent of the total source count as galactic stars. For the whole of the ROSAT all-sky survey we may therefore expect about one third of the total sources to be of stellar origin. The vast majority of these stellar X-ray sources is of coronal origin (i.e., late-type low mass stars). Only a relatively small number of stellar X-ray sources will be associated with early-type massive stars where the X-ray emission is thought to arise from instabilities in their radiatively driven winds or metal-poor degenerate stars where the X-ray emission comes from portions of the atmosphere considerably hotter than the optically visible photosphere. From the preliminary analyses performed so far it is already clear now that supersoft sources such as white dwarfs do not constitute a major fraction of the X-ray source population found in the ROSAT all-sky survey and the number of newly X-ray discovered white dwarfs will certainly be considerably less than one thousand. The X-ray emitting late-type stars are commonly referred to as ”active” stars, and the ROSAT all-sky survey catalog will comprise the most extensive list of such objects.
High Resolution Observations of the Solar Corona
Authors: Gomez D. , Golub L.
Published: June 2019

Soft X-ray images of the solar corona obtained during the last 20 years have systematically shown an intimate relationship between intense emitting structures and magnetic fields (Vaiana and Rosner 1978). The magnetic field confines a 106 K plasma, which is an intense source of soft X-ray photons. Therefore, it is natural to expect the bright X-ray structures to follow the field’s geometry. But this relationship does not seem to be just geometrical. It is generally believed that the energy necessary to heat the plasma comes from the dissipation of magnetic stresses, which are continually being re-generated by subphotospheric convective motions. However, there is still great uncertainty about the precise physical mechanisms involved in the production and release of the magnetic energy.
A Unified Picture of Large-Scale Structure
Authors: Bahcall Neta A.
Published: June 2019

A consistent picture of large-scale structure appears to be emerging from different types of observations including the spatial distribution of galaxies, clusters of galaxies, narrow pencil-beam surveys, and quasars. I describe these observations below. A network of large-scale superclusters, up to ~ 150 Mpc in scale, is suggested. The supercluster network surrounds low-density regions of similar scales, suggesting a “cellular” structure of the universe. (Ho = 100 km /s/ Mpc is used).
Quasar Activity in Rich Galaxy Clusters
Authors: Yee H. K. C. , Ellingson E.
Published: June 2019

We have carried out a number of imaging surveys of fields around quasars to study their global environments (e.g. Yee and Green 1987, Ellingson, Yee and Green 1991). The richness of the galaxy cluster environment of each quasar was determined using the galaxy-quasar spatial covariance amplitude, a quantity which is normalized for the expected luminosity and spatial distribution of galaxies (Longair and Seldner 1978, Yee and Green 1987). We find that ~40% of the brightest radio-loud quasars inhabit rich clusters of galaxies (Abell class 1 or higher) at z≳0.5 whereas only fainter AGN inhabit clusters at more recent epochs (Figure 1). This can be understood if quasars in rich clusters evolve much faster than those in poor environments.
Archiving of Current Observational Data on Variable Stars
Authors: Dubois P.
Published: June 2019

The first question is : which types of data should we archive for variable stars?

Let us consider the three following types of data : (i) raw data (output of the telescope, time…); (ii) reduced data (flux, magnitude…); (iii) processed data (light curve…).

We generally need the third one and use the reduced data only when we have trouble with the processed data or when we could obtain better processed data. We never quite go back to the raw data. The situation could evolve with raw data obtained with the CCD frame where the reduction procedure is more complex than with electronic counts. Then, at first sight, we have first to archive the processed data, then make an effort on reduced data and raw data.
Student Projects using Astronomical Data Bank
Authors: Gerbaldi M. , Dupré J.
Published: June 2019

There are several ways to use a computer with students for teaching Astronomy. Among many others we can list the following : to emulate and to explain the phenomena as with a planetarium, to visualise some astronomical properties such as the motions in a binary-stars system, or to simulate some observations with a telescope. We shall present here a different approach : the use of a computer to compute and to analyse the content of an astronomical data bank.

The projects developed with the students, in this context, allow them to have access to real astronomical data obtained by professional astronomers and then to make an analysis of the data based on their own knowledge.
Daytime astronomical observing conditions at South Pole
Authors: Harvey J
Published: June 2019

The Sun has been observed at South Pole nearly every austral summer since 1979. This experience shows that the duration of uninterrupted observations is limited by clouds to runs of at best ~150 hours. Impressively high duty cycles can be achieved over longer periods. Sky clarity is often superb but even in cloudless conditions, ice crystal precipitation storms can be a problem. Daytime observations of the Sun and bright stars show that visible seeing quality is limited to about 2-3 arc seconds at altitudes of 15-20 degrees. Nearer the zenith, the seeing quality approaches 1 arc second in light wind. Seeing quality appears to vary with wind speed and direction and also diurnally with changing solar illumination of the surface ridges (sastrugi). Seeing is degraded by turbulence in the exceptionally large temperature gradient in the first few hundred meters above the surface. There are suggestions that both daytime and, perhaps more so, nighttime cloudiness increased over the last decade. This may be related to increasing amounts of CO2, CH4 and CFCs in the polar atmosphere.
French plans for astronomy in Antarctica
Authors: Puget J L
Published: June 2019

French astronomers have been involved in research programs in Antarctica since 1979 when a successful campaign on helioseismology was done by a collaboration between the Nice University and the Bartol foundation. Several campaigns followed on this subject. In 1984 sub-mm observations of the diffuse galactic emission were done by a collaboration between the LPSP (Verrières le Buisson) and the Bartol foundation. These showed the high quality of the site for such observations not only because of the low water vapour content, which gives good transparency, but also because of the very low sky noise.
Singled Out or Drawn In? Social Polices and Lone Mothers’ Political Engagement
Authors: Shore Jennifer
Published: June 2019

Although it is no longer a symbol of socially degenerate behavior in many societies, single motherhood remains associated with numerous risks and disadvantages. In addition to their disadvantages in the labor market and their greater risk of poverty, single mothers also tend to be less politically active. This article explores the patterns of single mothers’ electoral participation across 25 European countries. In addition to the individual-level characteristics that shape the likelihood of taking part in an election, public policies can also do a great deal to encourage political involvement. Drawing on data from the European Social Survey combined with national family and labor market policies, I examine the ways in which policies aiming to reconcile the responsibilities at work and home can draw single mothers into political engagement. I find that early childhood expenditures and cash benefits to families are positively related to single mothers’ political participation.
On [Tibullus] III, 19 (IV, 13)
Authors: Lee A. G.
Published: June 2019

In considering whether or not this poem is genuine Tibullus we have only internal evidence to go on. Internal evidence is often not conclusive enough. It is difficult to assess, and the assessment usually involves a subjective element. The ideal is to reduce this subjective element to a minimum, to appeal to logic in the way a textual critic does when he chooses one MS reading rather than another or decides to admit an emendation of the text. The textual critic's choice of reading or the truth of his emendation cannot be proved in the way a madiematical theorem can be proved, but none the less we can know that the critic is right or wrong on grounds of probability, which in this field is the only available criterion.

I want now to point to the kind of internal evidence I shall appeal to: it is literary reminiscence, or imitation. Most often no deductions at all about priority can be drawn from parallel passages in different authors; one simply notes them and that is that. But sometimes a deduction about priority can be made. Under what conditions? And precisely how? To answer these questions I shall quote an example from English poetry, because it is particularly instructive to see ‘imitation’ at work in one's own language.
Inconsistency of Plot and Character in Aeschylus
Authors: Dawe R. D.
Published: June 2019

The plays of Aeschylus contain many contradictions, and much recent criticism of the dramatic technique of this author has been directed at attempts to extract from these contradictions a unified picture of what the poet really intended us to understand in the case of each particular play. Within the last few years no less than four major articles have been devoted to giving a logically consistent interpretation of the Seven, and if one extends the range to, say, the last thirty years, one can find that all the plays of Aeschylus have been subjected to criticism of a similar kind.

All this may seem entirely praiseworthy; and yet, as we come to read more and more of these books and articles, the sensation may grow upon some of us that we are not so much learning about Aeschylus as witnessing the transactions of a private club: transactions conducted with admirable propriety, but according to a system of rules which has been left unrevised for too long, untouched even after the notorious affair of the Suppliants. Although the members of this club are willing to challenge each others' view-points, they are all agreed that no gentleman would venture to call in question the one great assumption that underlies all their discussions: namely that Aeschylus could not possibly have constructed plays in which such contradictions were deliberately intended; and only seldom can he be allowed to have contradicted himself by oversight.
A Type of Hyperbaton in Latin Prose
Authors: Adams J. N.
Published: June 2019

False generalisations have often been made about the use of hyperbaton in Latin prose. According to Hofmann-Szantyr, for instance, ‘die klass. Prosa geht im Gebrauch des Hyperbatons…kaum über die Praxis des Aldateins hinaus'. The same scholars also imply that even when Cicero and Caesar do separate a substantive from its attribute, the separating word is seldom a verb. Again, E. Fraenkel, while showing that long disjunctions are common in Cicero, has maintained that hyperbaton ‘vielmehr ist… in der Umgangssprache zuhause’.

E. Skard has recendy pointed out the frequency with which Cornelius Nepos uses hyperbaton of the kind which comprises a substantive separated from its attribute by a verb. Since Skard accepts the above assertions of Hofmann-Szantyr, he is led to suggest that Nepos must have been following a Greek master. The favoured candidate is Dionysius of Halicarnassus. Dionysius not only has hyperbaton more often than any earlier Greek prose author; his work περὶ ἐνδόξων ἀνδρῶν may have been a source for some of Nepos' biographies.

It is the purpose of this paper to discuss the history of one type of hyperbaton in Latin prose, that consisting of a verb standing between a substantive and its adjective (henceforth for convenience referred to as ‘verbal hyperbaton’). It will be demonstrated that, however easy disjunction might seem in a synthetic language, our device was artistic rather than natural to ordinary speech. The statements of Hofmann-Szantyr mentioned above will be shown to be inaccurate, and Skard's hypothesis to be unnecessary.
The ‘Dirae’
Authors: Goodyear F. R. D.
Published: June 2019

Battare, cycneas repetamus carmine uoces, diuisas iterum sedes et rura canamus, rura quibus diras indiximus, impia uota:

ante lupos rapient haedi, uituli ante leones, delphini fugient pisces, aquilae ante columbas, et conuersa retro rerum discordia gliscet — multa prius fient quam non mea libera auena montibus et siluis dicat tua facta, Lycurge. impia Trinacriae sterilescant gaudia uobis nec fecunda, senis nostri felicia rura, semina parturiant segetes, non pascua colles, non arbusta nouas fruges, non pampinus uuas, ipsae non siluae frondes, non flumia montes.
A non-invasive approach to determining extent of degradation in the rumen
Authors: Crompton L.A. , France J. , Kebreab E. , Mills J.A.N. , Dhanoa M.S. , López S. , Dijkstra J.
Published: June 2019

A non-invasive method is proposed for determining the extent of degradation in the rumen, based on the gas production technique and mathematical modelling. The exercise involves developing both a statistical model and a kinetic model (France et al., 2000). The statistical model shifts (or maps) the gas accumulation profile obtained using a faecal inoculum to a rumen gas profile, thus obviating the need for rumen sampling. The kinetic model determines the extent of degradation in the rumen from the shifted profile. It is presented as a generalised mathematical function, allowing any one of a number of alternative equation forms to be selected.
Comparison of methods for prediction of rumen fermentation patterns from diet composition
Authors: Brown V.E. , Agnew R.E. , Kilpatrick D.J.
Published: June 2019

Previous attempts (Offer & Percival, 1998) have been made to develop a prediction system for rumen fermentation patterns from stepwise multiple linear regressions of the chemical constituents of the diet. These authors have also made comparisons between equations derived from diet wet chemistry and those developed from near infrared reflectance spectroscopy (NIRS). However, the potential of NIRS to predict the dynamics of rumen fermentation has not fully been explored using a wide range of forage treatments. Therefore the objective of this experiment was to develop equations from the chemical composition of the diet to predict rumen fermentation patterns and compare these with equations developed from undried and dried NIRS scans of the diets.
Microbial activity in grass-fed in-vitro continuous cultures in response to infusion of graded levels of soluble sugars
Authors: Lee M.R.F. , Leemans D.K. , Davies D.R. , Merry R.J. , Moorby J. M. , Humphreys M.O. , Theodorou M.K. , MacRae J.C. , Scollan N. D.
Published: June 2019

Novel lines of high sugar ryegrass have been shown to increase the efficiency of N use and milk production in zero-grazed cattle (Miller et al., 1999). An experiment was carried out to determine whether this was in part due to an increase in the efficiency of microbial protein synthesis in response to the amount and availability of water soluble carbohydrate (WSC) increasing the balance between energy and nitrogen supply to the rumen microbial population.
Body tissue changes in Scottish Blackface ewes during one annual production cycle
Authors: Lambe N. R. , Young M. J. , Conington J. , Lewis R.M. , Simm G. , Bishop S. C.
Published: June 2019

Fat and muscle reserves are mobilised during winter by breeding hill ewes, living in harsh environments, as they conceive and carry their lambs (Russel et al., 1968). Tissue depletion and repletion were studied in Scottish Blackface ewes through one productive cycle using computed tomography (CT). The aim was to use this nondestructive method to quantify patterns of change in carcass fat, carcass muscle and internal fat in ewes of differing age and reproductive status.
The effect of midwinter shearing on rumen digesta kinetics in highly prolific crossbred ewes
Authors: Šebek L.B.J. , Everts H.
Published: June 2019

The effective rumen degradability (ERD) of dietary protein is used to quantify the amount of dietary protein entering the small intestine of ruminants. Midwinter shearing of prolific ewes increases rumen degradation rate (Kd) of dietary protein (Šebek and Everts, 1999). However, these differences in Kd may be compensated by a different rumen passage rate (Kp), since cold exposure is often associated with increases in Kp. Kp can be estimated by use of an undegradable marker. This method, although reliable for fluids seems less reliable for solids. The objective of the present experiment was to quantify the effect of midwinter shearing on ERD in highly prolific ewes. As an alternative to the use of Kp, ERD of crude protein (CP) and of protein-free-organic-matter (OM_CP) were estimated from periodical changes in rumen volume partitioned as rumen degradable (Xd) and rumen undegradable (Xu) components.
Ah receptor expression and signal transduction in bovine and rabbit reproductive tissues and embryos
Authors: Fischer B , Hasan A , Kietz S , Pocar P
Published: June 2019

Polychlorinated biphenyls (PCB) are persistent environmental contaminants that have been reported to adversely affect reproduction in mammals. The exact mechanism of action of these chemicals on oocyte and embryo development are not known. Previous studies in our laboratory demonstrated that PCB adversely affect in vitro oocyte maturation and embryo development in two different in vitro systems (cattle, rabbit). The objective of present study was to investigate the possible role of the arylhydrocarbon receptor (AhR) in PCB toxicity. The AhR is a transcription factor activated by ligands such as dioxins or PCB. Its transcriptional activity depends on dimerisation with its nuclear partner ARNT. The presence of AhR and ARNT was investigated in bovine and rabbit genital tract (uterus, ovary) and embryonic tissues, employing RT-PCR and immunohistochemistry.
A wax diet for administration of octylphenol to laboratory rodents as a tool for the investigation of oestrogenic activity
Authors: Milligan S.R. , Sales G.D. , Pocock V.J.
Published: June 2019

The use of controlled dietary intake for administration of environmental oestrogens to laboratory animals is essential in assessing the real threat of natural exposure to these compounds. Although human and animal exposure to environmental chemicals is mostly through diet or water, administration of these chemicals to laboratory animals is usually via injection. In this study, in order to overcome the problem of unpalatability of high doses of chemicals, a wax and a powdered diet were designed. These diets were used as vehicles for administration of the environmental oestrogen octylphenol (OP) to non-pregnant, pregnant and lactating laboratory rats and the dose of dietary octylphenol required to induce oestrogenic effects in the reproductive tract of female animals was determined.
Effects of a high-fat diet based on palm, soybean or maize oil on growth performance and carcass characteristics in growing-fattening pigs
Authors: Ocampo A , Lean I J
Published: June 2019

Diets for growing-fattening pigs are normally low in fat and based on cereals, which supply approximately two thirds of the total energy required by pigs. Restricted concentrations of oil (between 2 and 10% of total dry matter) have been used to improve growth rate and feed efficiency. Palm oil and oil palm by-products have been used as the main energy source in the growth cycle as substitutes for cereals (Ocampo and Lean 1999). The objective of this experiment was to evaluate three oils as dietary substitutes for maize grain in growing-fattening pigs, based on growth performance and carcass characteristics using ultrasonic measurements.
Implications of changing the housing conditions of pigs prior to slaughter for the eating quality of bacon
Authors: Maw S.J. , Fowler V.R , Hamilton M. , Petchey A.M.
Published: June 2019

Commercial housing conditions are known to have an effect on the eating quality of bacon. Significant differences have been shown between pigs reared on solid concrete floors or straw-bedded accommodation (Maw et al. In press). Also high levels of dietary Vitamin E have been shown to improve pigmeat quality (Buckley et al., 1995). This experiment was carried out to examine whether the effects of housing could be eliminated or reversed by altering housing conditions or reduced by dietary supplementation with Vitamin E.
Sheep avoidance of faeces creates a foraging trade-off between nutrient and parasite intake
Authors: Hutchings M. R. , Gordon I. J. , Kyriazakis I. , Jackson F.
Published: June 2019

Gastrointestinal (GI) parasites, acquired by sheep through the action of foraging, are the most pervasive challenge to their survival and reproduction. The eggs of many GI parasite species are deposited on pasture in faeces where they develop into infective stage larvae that contaminate surrounding swards. We test the hypotheses that (1) faeces and hence parasite avoidance behaviour of sheep creates a grazing trade-off between nutrition and parasitism and (2) the relative costs and benefits of the trade-off in relation to animal state of infection (parasitized, non-parasitized, immune) determines their subsequent grazing behaviour.
Distribution of potentially probiotic Lactobacillus spp. in pig farms
Authors: Hillman K. , Robertson S. M.
Published: June 2019

Isolates of Lactobacillus spp were obtained from colon samples from a total of 26 randomly selected Scottish piggeries. These were screened for probiotic potential, assessed by their ability to inhibit the growth of Escherichia coli K88. It emerged that the distribution of potentially probiotic isolates was not uniform: certain piggeries seemed to harbour populations of Lactobacillus spp. with a high proportion of potential probiotics, while other piggeries yielded few or no active isolates. We postulate that this distribution may influence the perceived variation in efficacy of commercial probiotic preparations.
Rumen environment modifications in sheep fed with brewers’ grain silage in Brazil
Authors: Filho S.L.S. Cabral , Bueno I.C.S. , Abdalla A.L.
Published: June 2019

The roughage supplementation with some industrial by-products is an alternative on feed management. The great number of brewery in Brazil and the wet brewers’ grain nutritional value are an attractive possibility for use in sheep diets, mainly for its availability during the year and its fibre quality. The inclusion of this feed in high proportions on sheep diets could modify rumen environment. The objective of this paper was to evaluate the modifications on rumen environment caused by addition of brewers’ grain silage as fibre source on sheep diets.
Evaluation of the Indonesian coffee pulp as a ruminant feed using the Reading Pressure Technique
Authors: Fakhri S. , Latief A. , Murni R. , Widyawati S.D. , Afdal M. , Mould F.L.
Published: June 2019

Indonesia is the world’s third largest producers of coffee with the residual coffee pulp being included in ruminant diets. However, coffee pulp has a low palatability although studies have shown that this can be increased by ensiling. In addition, coffee pulp contains anti-nutritive factors such as caffeine and tannins. Washing the residue with hot water reduces caffein concentration by about 90 % (Kiflewahid, 1982). In this study, the effects of washing and ensilage on the degradability profiles were examined by estimating gas release using the Reading Pressure Technique.
Time course of changes in the fatty acid composition of plasma in the milk fed pre-ruminant calf supplemented with a palm/rapeseed oil mixture or fish oil
Authors: O’Brian R. , Muturi N. , Birnie M. , Wallace M. , Struthers J. , Scaife J. R.
Published: June 2019

In pre-ruminant calves the oesophageal groove reflex allows milk to bypass the developing rumen and is a mechanism by which dietary fatty acids can be delivered directly to the small intestine. This experiment was a pilot study carried out to establish the extent and time course of the changes in plasma fatty acid composition in calves fed milk supplemented with oils of differing fatty acid composition and allowed minimal access to roughage (straw bedding). The work was carried out to provide baseline data for a longer study with calves in which rumen development will be encouraged by feeding solid food but the oesophageal groove reflex will be maintained through long term milk feeding and used as a means of delivering polyunsaturated fatty acids (PUFA) directly to the small intestine.
Ruminal peptide-N concentrations in Iranian Balochi lambs fed diets containing lucerne hay or silage
Authors: Moosavi A R Heravi , Mesgaran M Danesh
Published: June 2019

Peptides are intermediates in the conversion of ingested protein to ammonia in the rumen and their accumulation depends upon the nature of diet (Mesgaran & Parker, 1995). Transient accumulation of peptides occurs after feeding and then their concentrations declines. In addition, it suggests that the production of peptides in the rumen was not altered by the protein supplements when diets provided similar effective rumen degradable protein (ERDP)(Mesgaran & Moosavi, 1999). The objective of the present experiment was to investigate the effect of diets, with similar ERDP, containing lucerne hay or silage on the ruminal peptide-N concentrations.
The impact of hexose partitioning in sheep in vivo
Authors: Moss A. R. , Newbold C. J. , Givens D.I.
Published: June 2019

Methane production represents an important sink for hydrogen within the rumen Beever (1993) suggested that the partitioning of fermentable dry matter (DM) between microbial synthesis and fermentation products would alter the pattern of hydrogen production and hence methanogenesis. This hypothesis was investigated in vitro using a range of diets varying in carbohydrate source (Moss et al., 2000). Methane production (moles) increased as the proportion of DM fermented to short chain fatty acids (SCFA) increased and this was related to decreasing water soluble carbohydrate (WSC) to cell wall (NDF) ratio of the diet. The objectives of the current study was to design diets with a range of WSC:NDF ratios and to measure the impact on hexose partitioning and methane production in sheep in vivo.
The effects of liquid feed on the small intestine mucosa and performance of piglets at 28 days postweaning
Authors: Hurst D. , Lean I. J. , Hall A. D.
Published: June 2019

It is well established that villus atrophy and crypt hyperplasia occur at weaning reducing the digestive and absorptive capacity of the small intestine in piglets. Liquid feeding appears to improve intake and growth in piglets but little is known about the effects of liquid feed on the small intestine mucosa. Deprez et al (1987) reported higher villi 11 days after weaning in piglets fed a liquid diet but there is little evidence that these changes persist in older pigs or are specifically due to diet form. This study is part of a series evaluating the effect of liquid feed on pig performance and adaptive changes in the absorptive mucosa of pigs from weaning to slaughter.