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This study explores the potential of Spanish germplasm for the development of hybrids adapted to southern Europe, a new region for hybrid barley (Hordeum vulgare). A set of 140 locally adapted, advanced breeding lines, developed in a Spanish public breeding program, were evaluated for their potential to widen the germplasm available for hybrid barley development. A subset of 24 lines was introduced into three‐way hybrid combinations and tested in a field trial network of four locations and 2 yr. The hybrid performance of the rest of the lines was estimated based on genomic prediction models. No three‐way hybrid exceeded the best check. We succeeded in identifying lines with high general combining ability, which could produce promising two‐way hybrids. Some were among those tested in the field, whereas others resulted from genomic predictions, validating the strategy followed of mining locally adapted breeding lines. Rachis brittleness detected in field trials revealed a low but detrimental effect of the presence of alternative brittle mutations in the hybrid combination. The success of hybrid breeding in southern Europe requires further investigation of the underlying heterotic patterns, and appropriate management of brittle genes through prebreeding, to widen the germplasm accessible for hybrid barley breeding. Core Ideas: A combination of field testing and genomic prediction successfully mined local germplasm for hybrid development.Reduced expression of local diversity and heterosis in three‐way hybrids hampered obtaining superior hybrids.High‐yielding, widely adapted, parental lines for the development of promising two‐way hybrids were identified.Field‐estimation of rachis fragility indicates risk of grain loss in hybrids with alternative brittle mutations.The success of hybrid barley in southern Europe requires managing flowering time and studying heterotic patterns. [ABSTRACT FROM AUTHOR]

Lithic artifacts were still in use in Bronze Age Europe, in spite of the emergence of a new technology, namely metallurgy, during this period. In fact, stone technology continued to be used everywhere until at least the end of the Early Bronze Age, and even until the end of the Late Bronze Age in specific areas. This is especially true for Greece where lithic raw material and/or tool networks were still operating during the whole Bronze Age. During the Middle Bronze Age in mainland Greece, obsidian and high-quality chert were still widely used, especially in settlements. This raises the question of the necessity of the use of obsidian instead of a stronger or more versatile material (chert or metal). Why was volcanic glass, which required considerable investment in terms of know-how and long-distance transportation, still used in spite of the technological context (where metallurgy was already developed)? The purpose of this paper is to contribute to this debate through the use-wear analysis of obsidian tools. Artifacts from settlement levels of the Middle Helladic site of Kirrha (Phocis, Greece) have been examined. In this domestic-use context, bronze and chert were also found. The main results of this study show an exclusive form and use of obsidian: bladelets were used for cutting soft and siliceous plant matter, with the exception of Graminae harvesting activity. These results point to the specialization of the lithic industry in terms of raw materials, where sharp obsidian artefacts were employed for cutting of soft and flexible materials, depending on the relative brittleness of the rock, at least at Kirrha. Thus, among the numerous propositions concerning continued obsidian circulation during the entire Bronze Age, a functional use (at least) could be proven, if this observation is also made elsewhere in Greece. [ABSTRACT FROM AUTHOR]

European (EC2) and ACI 318-08 design code rules for lap splices of reinforcing bars within a bundle differ markedly--the former permits the same or shorter lap-splice lengths with respect to splices of individual bars, while the latter requires longer laps. This paper reports an investigation into the performance of lap splices of individual bars within a bundle of two or three. The results show that the bond strength of individual bars is not reduced on account of their forming part of a bundle (contrary to the provisions of ACI 318-08). Staggered laps were found to be weaker but fail in a less brittle manner when splices are staggered longitudinally as compared to equivalent laps, in which all bars are spliced at the same section whether or not bars were bundled. Therefore, the outcome raises the question of the validity of reductions permitted by both the ACI 318-08 and European (EC2) codes, where only a portion of the bars is lap-spliced at a section. It is recommended that further investigation of the influence of the proportion of bars lapped at a section on splice performance be undertaken. [ABSTRACT FROM AUTHOR]

Connections with mechanical fasteners are important for all cases of timber structures. The failure of these connections may occur in either ductile or brittle manner. For the calculation of the ductile failure strength or the load carrying capacity, the European yield model (EYM) is used in many standards and accepted as a very accurate model. In the current New Zealand timber standard NZS 3603:1993 (Standards New Zealand, 1993) and the Australian one AS1720.1-1997 (Standards Australia, 1997), the design concept for bolted or dowelled connections is not based on the EYM, and depends only on the diameter, the timber thickness and the species group. The most important parameters for the EYM are the fastener yield moment and the timber embedment strength, but embedment strength values are not available for New Zealand Radiata pine or laminated veneer lumber (LVL). To obtain the missing information and to implement the EYM into the New Zealand and Australian standards, embedment tests parallel, perpendicular and under various load-to-grain angles with different dowel diameters in Radiata pine lumber and LVL were conducted and compiled to build a database of embedment strength values. This paper includes the latest results of the investigations with dowel diameters extended up to 30 mm. Furthermore, different international testing standards are compared and their evaluation methods are used. The test results are also compared with the corresponding results using the Eurocode 5 formulas, and show that adjusted formulas of the Eurocode 5 can be used to predict the load carrying capacity of bolted and dowelled connections in Radiata pine lumber and LVL. Design examples comparing the current methods from the New Zealand/Australian design standards and the proposed method adopted from the EYM of the European design standard are given as well. [ABSTRACT FROM AUTHOR]

A two-dimensional thermorheological model of the Central Alps along a north–south transect is presented. Thermophysical and rheological parameters of the various lithological units are chosen from seismic and gravity information. The inferred temperature distribution matches surface heat flow and results in Moho temperatures between 500 and 800 °C. Both European and Adriatic lithospheres have a ‘jelly-sandwich’ structure, with a 15–20 km thick brittle upper crust overlying a ductile lower crust and a mantle lid whose uppermost part is brittle. The total strength of the lithosphere is of the order of 0.5–1.0 × 1013 N m−1 if the upper mantle is dry, or slightly less if the upper mantle is wet. In both cases, the higher values correspond to the Adriatic indenter. [ABSTRACT FROM AUTHOR]