Procedure at the magnetic observatories of the United States Coast and Geodetic Survey

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Breeding Morphogenetic Traits to Match Genotypes to Their Utilization

A divergent selection for lamina length was done from natural populations of perennial ryegrass. Tested in a multi-site experiment in France, the short-leaved perennial ryegrass was more productive under simulated grazing and less productive under infrequent cutting than the long-leaved perennial ryegrass. Matching cultivars to their management is possible by selecting for morphogenetic traits. However, our results suggest the range of adaptation to different managements of perennial ryegrass cultivars could be extended by increasing their phenotypic plasticity

Prediction of Seed Yield of Festuca x Lolium Hybrids from the Nursery Mother Plants

In order to develop commercial Festuca x Lolium hybrids, their seed production has to be improved. Seed yields of Festuca x Lolium progenies were assessed in dense plots. Prediction of those seed yields was based on the morphological observations done on spaced plants in the nursery of both mother plants and their progenies. The best prediction of the progeny seed yields is a linear regression on the stem density and the seed weight per inflorescence assessed on the mother plants

The Metallicity of High Redshift Galaxies: The Abundance of Zinc in 34 Damped Lyman Alpha Systems from z = 0.7 to 3.4

We report new observations of ZnII and CrII absorption lines in 10 damped \lya systems (DLAs), mostly at redshift z_{abs} \simgt 2.5 . By combining these results with those from our earlier survey (Pettini et al. 1994) and other recent data, we construct a sample of 34 measurements (or upper limits) of the Zn abundance relative to hydrogen [Zn/H]; the sample includes more than one third of the total number of DLAs known. The plot of the abundance of Zn as a function of redshift reinforces the two main findings of our previous study. (1) Damped \lya systems are mostly metal-poor, at all redshifts sampled; the column density weighted mean for the whole data set is [Zn/H] $= -1.13 \pm 0.38$ (on a logarithmic scale), or approximately 1/13 of solar. (2) There is a large spread, by up to two orders of magnitude, in the metallicities we measure at essentially the same redshifts. We propose that damped \lya systems are drawn from a varied population of galaxies of different morphological types and at different stages of chemical evolution, supporting the idea of a protracted epoch of galaxy formation. At redshifts z \simgt 2 the typical metallicity of the damped \lya systems is in agreement with expectations based on the consumption of HI gas implied by the recent measurements of $\Omega_{DLA}$ by Storrie-Lombardi et al. (1996a), and with the metal ejection rates in the universe at these epochs deduced by Madau (1996) from the ultraviolet luminosities of high redshift galaxies revealed by deep imaging surveys. There are indications in our data for an increase in the mean metallicity of the damped \lya systems from $z > 3$ to $\approx 2$, consistent with the rise in the comoving star formation rate indicated by the relative numbers of $U$ and $B$ drop-outs in the Hubble Deep Field. Although such comparisons are still tentative, it appears that these different avenues for exploring the early evolution of galaxies give a broadly consistent picture.Comment: 51 pages, LaTeX, 9 Postscript Figures. Accepted for publication in the Astrophysical Journa

A slitless spectroscopic survey for quasars near quasars

We present the results of the Quasars near Quasars (QNQ) survey, a CCD-based slitless spectroscopic survey for faint V<22 quasars at 1.7<z<3.6 on 18 26.2'x33.5' fields centred on bright quasars at 2.76<z<4.69. In total 169 quasar candidates with emission lines were selected from the extracted flux-calibrated spectra on the basis of well-defined automatic selection criteria followed by visual inspection and verification. With follow-up spectroscopy of 81 candidates that were likely to reside at z>1.7 we were able to confirm 80 new quasars at 0.580<z<3.586 on 16 of our fields. 64 of the newly discovered quasars are located at z>1.7. The overall high success rate implies that most of the remaining 88 candidates are quasars as well, although the majority of them likely resides at z<1.7 on the basis of the observed line shapes and strengths. Due to the insufficient depth of the input source catalogues needed for extraction of the slitless spectra our survey is not well defined in terms of limiting magnitude for faint 2.5<z<3.6 quasars whose Lyman alpha emission is detectable well beyond V=22, albeit at a continuum S/N<1. While not useful for characterising the evolving space density of quasars, our sample provides many new closely spaced quasar sightlines around intensely studied quasars for further investigations on the three-dimensional distribution of the intergalactic medium.Comment: 18 pages, 16 figures, accepted by A&A, includes Table 2 from online material, full paper with appendices containing additional figures and tables available at http://www.aip.de/People/gworseck/qnqpaper/qnqpaper_final.pd

Dysregulation of metabolic-associated pathways in muscle of breast cancer patients: preclinical evaluation of interleukin-15 targeting fatigue

Background Breast cancer patients report a perception of increased muscle fatigue, which can persist following surgery and standardized therapies. In a clinical experiment, we tested the hypothesis that pathways regulating skeletal muscle fatigue are down-regulated in skeletal muscle of breast cancer patients and that different muscle gene expression patterns exist between breast tumour subtypes. In a preclinical study, we tested the hypothesis that mammary tumour growth in mice induces skeletal muscle fatigue and that overexpression of the cytokine interleukin-15 (IL-15) can attenuate mammary tumourinduced muscle fatigue. Methods Early stage non-metastatic female breast cancer patients (n = 14) and female non-cancer patients (n = 6) provided a muscle biopsy of the pectoralis major muscle during mastectomy, lumpectomy, or breast reconstruction surgeries. The breast cancer patients were diagnosed with either luminal (ER+ /PR+ , n = 6), triple positive (ER+ /PR+ /Her2/neu+ , n = 5), or triple negative (ER/PR/Her2/neu, n = 3) breast tumours and were being treated with curative intent either with neoadjuvant chemotherapy followed by surgery or surgery followed by standard post-operative therapy. Biopsies were used for RNA-sequencing to compare the skeletal muscle gene expression patterns between breast cancer patients and non-cancer patients. The C57BL/6 mouse syngeneic mammary tumour cell line, E0771, was used to induce mammary tumours in immunocompetent mice, and isometric muscle contractile properties and fatigue properties were analysed following 4 weeks of tumour growth. Results RNA-sequencing and subsequent bioinformatics analyses revealed a dysregulation of canonical pathways involved in oxidative phosphorylation, mitochondrial dysfunction, peroxisome proliferator-activated receptor signalling and activation, and IL-15 signalling and production. In a preclinical mouse model of breast cancer, the rate of muscle fatigue was greater in mice exposed to mammary tumour growth for 4 weeks, and this greater muscle fatigue was attenuated in transgenic mice that overexpressed the cytokine IL-15. Conclusions Our data identify novel genes and pathways dysregulated in the muscles of breast cancer patients with early stage non-metastatic disease, with particularly aberrant expression among genes that would predispose these patients to greater muscle fatigue. Furthermore, we demonstrate that IL-15 overexpression can attenuate muscle fatigue associated with mammary tumour growth in a preclinical mouse model of breast cancer. Therefore, we propose that skeletal muscle fatigue is an inherent consequence of breast tumour growth, and this greater fatigue can be targeted therapeutically

Review: Towards the agroecological management of ruminants, pigs and poultry through the development of sustainable breeding programmes. II. Breeding strategies

Agroecology uses ecological processes and local resources rather than chemical inputs to develop productive and resilient livestock and crop production systems. In this context, breeding innovations are necessary to obtain animals that are both productive and adapted to a broad range of local contexts and diversity of systems. Breeding strategies to promote agroecological systems are similar for different animal species. However, current practices differ regarding the breeding of ruminants, pigs and poultry. Ruminant breeding is still an open system where farmers continue to choose their own breeds and strategies. Conversely, pig and poultry breeding is more or less the exclusive domain of international breeding companies which supply farmers with hybrid animals. Innovations in breeding strategies must therefore be adapted to the different species. In developed countries, reorienting current breeding programmes seems to be more effective than developing programmes dedicated to agroecological systems that will struggle to be really effective because of the small size of the populations currently concerned by such systems. Particular attention needs to be paid to determining the respective usefulness of cross-breeding v. straight breeding strategies of well-adapted local breeds. While cross-breeding may offer some immediate benefits in terms of improving certain traits that enable the animals to adapt well to local environmental conditions, it may be difficult to sustain these benefits in the longer term and could also induce an important loss of genetic diversity if the initial pure-bred populations are no longer produced. As well as supporting the value of within-breed diversity, we must preserve between-breed diversity in order to maintain numerous options for adaptation to a variety of production environments and contexts. This may involve specific public policies to maintain and characterize local breeds (in terms of both phenotypes and genotypes), which could be used more effectively if they benefited from the scientific and technical resources currently available for more common breeds. Last but not least, public policies need to enable improved information concerning the genetic resources and breeding tools available for the agroecological management of livestock production systems, and facilitate its assimilation by farmers and farm technicians