Haltungsbedingungen, Leistung und Gesundheit von gängigen Legehennen-Genotypen in Öko- und Freilandhaltungen in Frankreich, der Schweiz und den Niederlanden

In Switzerland, France and The Netherlands 257 farmers keeping free ranging laying hens (organic and conventional) were interviewed with regard to genotype of the hens, management conditions and performance. In total, 21 different genotypes were present on the farms. The overall effect of system (organic vs. conventional) on egg production and mortality was significant, with higher mortality and lower egg production among organic hens. White hens tended to perform better and have a better feather cover than brown hens. Silver hens appeared to have a higher mortality and lower production per hen housed. In group discussions, farmers preferred a more robust, heavier hen with good intake capacity and good persistence. In organic systems, this hen type is more economic according to model calculations

Search for the ideal laying hen for organic and free range systems

Since 1960 the majority of commercial layers are housed in cages. Non-cage housing started to appear again from 1980 onwards and increases in importance. It is questionable if birds bred to perform in cages are also suited for free range housing. We examined the performance of current genotypes in free range systems (organic and conventional) by an inventory among laying hen farmers in Switzerland, The Netherlands and France (325 flocks on 275 farms) and organised workshops with farmers to discuss their ideas on breeding goals (‘the ideal hen’) for free range systems

Rock glaciers and mountain hydrology: A review

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.In mountainous regions, climate change threatens cryospheric water resources, and understanding all components of the hydrological cycle is necessary for effective water resource management. Rockglaciers are climatically more resilient than glaciers and contain potentially hydrologically valuable ice volumes, and yet havereceived lessattention, even though rock glacier hydrologicalimportance may increase under future climate warming. In synthesising data from a range of global studies, we provide the first compre-hensive evaluation of the hydrological role played by rock glaciers. Weevaluate hydrological significanceover a range of temporal and spatial scales, alongsidethe complex multiple hydrological processes with which rock glaciers can interact diurnally, seasonally, annually, decadally and both at local and regional extents.We report that although no global-extent, complete inventory for rock glaciers exists currently, recent research efforts have greatly elaborated spatialcoverage.Using these research papers,we synthe-sise information on rock glacier spatial distribution, morphometric characteristics, surface and subsurface features, ice-storage and hydrological flow dynamics, water chemistry, and future resilience, from which we provide the first comprehensive evaluation of their hydrological contribution. We identify and discuss long-, intermediate-and short-term timescales for rock glacier storage, allowing a more balanced assess-ment of the contrasting perspectives regarding the relative significance of rock glacier-derived hydrological contributions compared to other water sources.We show that further empirical observations are required to gain a deeper hydrological understanding of rock glaciers, in terms of(i) their genesis and geomorpho-logical dynamics (ii) total ice/water volume; (iii) water discharge; and (iv) water quality. Lastly, we hypothesisethat at decadal and longer timescales, under future climate warming, degradation of ice within rock glaciers may represent an increasing hydrological contribution to downstream regions, and thus in-creased hydrological significance while rock glacier water stores persist.Royal Geographical SocietyNatural Environment Research Council (NERC

Transcriptome-wide association study of breast cancer risk by estrogen-receptor status

Previous transcriptome-wide association studies (TWAS) have identified breast cancer risk genes by integrating data from expression quantitative loci and genome-wide association studies (GWAS), but analyses of breast cancer subtype-specific associations have been limited. In this study, we conducted a TWAS using gene expression data from GTEx and summary statistics from the hitherto largest GWAS meta-analysis conducted for breast cancer overall, and by estrogen receptor subtypes (ER+ and ER-). We further compared associations with ER+ and ER- subtypes, using a case-only TWAS approach. We also conducted multigene conditional analyses in regions with multiple TWAS associations. Two genes, STXBP4 and HIST2H2BA, were specifically associated with ER+ but not with ER- breast cancer. We further identified 30 TWAS-significant genes associated with overall breast cancer risk, including four that were not identified in previous studies. Conditional analyses identified single independent breast-cancer gene in three of six regions harboring multiple TWAS-significant genes. Our study provides new information on breast cancer genetics and biology, particularly about genomic differences between ER+ and ER- breast cancer.Peer reviewe

Tensile properties and interfacial interactions of bimodal hard/soft latex blends

In this work, the effect of composition, particle size and particle size ratio on the tensile properties of well-characterized hard/soft latex blends was investigated. Four blends of hard/soft latices, with varying particle sizes (either small or large), and volume fractions of 100/0, 80/20, 60/40, 50/50, 40/60, 20/80 and 0/100 were studied. The stress at break increased and the strain at break decreased as the amount of hard particles in the blend increased. A simple model, introduced by Pukanszky for filled polymers and polymer blends, proved to be a very useful tool for evaluating the tensile properties of the latex blends. Parameter B of the model could be related to the specific surface of the dispersed hard particles and the particle size ratio. Increasing the specific surface of the dispersed hard particles resulted in an increase in parameter B. The influence of particle size ratio on parameter B was shown to depend on the formation of aggregates

Origin of additional mechanical transitions in multicomponent polymeric materials

The viscoelastic properties of several multicomponent materials (including both particulate multipolymeric materials and multilayer polymer blends) were investigated in relation to their microstructures and phase-property dependencies. Theoretical considerations based on mechanical modeling were used to explore the origin of additional mechanical transitions in experimental viscoelastic spectra. The major part of this work was devoted to particulate multicomponent systems, and especially to the further exploration of the characteristics of the so-called micromechanical transition (MMT). Although such an additional phenomenon is clearly explained as a result of a specific interphase, our investigation also provides evidence that the occurrence of a MMT in dynamic mechanical spectra reflects the contribution of the geometrical arrangement into phases of a set of properties of the pure components, rather than a molecular relaxational process within the interfacial area. Finally, on the basis of an equivalent approach, the influence of the geometrical arrangement of phases on the viscoelastic response of multilayer polymer blends was pointed out as a relevant argument to justify the existence of "spurious" additional damping peaks in some experimental dynamic mechanical spectra reported in the literature

Interfacially induced additional damping peaks in dynamic mechanical spectra - micromechanical transitions in multipolymeric materials

The viscoelastic properties of several hypothetical multiphase polymeric materials were investigated in relation to their phase-property dependencies and microstructures. Theoretical mechanical considerations based on the self-consistent interlayer model were performed to point out that specific geometrical arrangements into phases of a set of properties of the pure constituents can lead to interfacially induced damping peaks in dynamic mechanical spectra (DMS). Such additional contributions in DMS were referred to micromechanical transitions to distinguish them from ordinary molecular transition

Dispersion and interaction of graphene oxide in amorphous and semi-crystalline nano-composites: a PALS study

The influence of dispersion and interaction of Graphene Oxide (GO) in semi-crystalline Polyhydroxy butyrate (PHB) and glassy amorphous Poly(tBP-oda) is explored by Positron Annihilation Lifetime Spectroscopy (PALS). The ortho-Positronium lifetimes which represent the main free volume hole size of both polymers are mainly affected by the large differences in internal stresses built up by the shrinkage of the polymers during their preparation, restricted by the platelet structure of GO. The ortho-Positronium intensities, which represent the ortho-Positronium formation probabilities, suggest a strong dependency of on the dispersion of the nano-particles and their aspect ratio

Melt-compounded salt-containing poly(ethylene oxide)/clay nanocomposites for polymer electrolyte membranes

The present study demonstrates the use of a simple and versatile melt-compounding route to prepare NaClO4-containing poly(ethylene oxide) PEO/clay nanocomposites combining excellent mechanical properties with a competitive level of the ionic conductivity. The nanostructure and the resulting thermal, mechanical and conductive properties of the salt-containing PEO/clay nanocomposites were found to be highly sensitive to the clay type, i.e. aspect ratio of the clay, to the presence of an organic modifier in the intergallery spacing, and to the salt concentration. The highest increase of the shear storage modulus is obtained in the presence of single silicate layers, thus an exfoliated nanostructure, having a high aspect ratio. These structures are only obtained with an (polar) organically modified clay (Cloisite 30B), regardless of the presence of salt. The use of non-organically modified clays (Cloisite Na+ and Laponite) resulted in intercalated nanocomposites, with only a minor improvement in stiffness. A strong interaction between the Na+ from NaClO4 and the Cloisite 30B silicate layers might be responsible for an increased PEO crystallinity and resultant additional increase in stiffness. A mechanism is proposed whereby the Na+ ions are drawn away from the PEO phase, to be complexed by the silicate layers, or even ion-exchanged with modifier cations. The addition of clay did not greatly affect the ion conductivity below the melt temperature of PEO. At higher temperatures, the nanocomposites displayed only slightly lower conductivities compared to the PEO/NaClO4 complex, due to the presence of the clay platelets