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Livestock grazing systems constitute a traditional activity in mountain areas. They are adapted to vegetation growth cycles in meadows, forests and grasslands, and deliver ecosystem services such as open landscapes, wildfires prevention, biodiversity maintenance and quality products. Climate change poses a new challenge on mountain grazing systems by impacting on its natural resource base. We used the model NODRIZA to evaluate the potential impact of three scenarios of altered pasture quality and quantity due to climate change (optimistic, medium and worst) and a business-as-usual scenario (BAU) on four beef farms representative of the existing grazing systems in the Spanish Pyrenees. We explored the role of traditional management practices (e.g. modifying the grazing season and early weaning) to cope with these changes. Cow body condition score, feed self-sufficiency and gross margin were the indicators of farms functioning. The optimistic scenario improved all farming indicators during most of the modelled period and then declined—still above BAU levels—in the long term. The medium scenario resulted in an initial improvement of farming indicators and a decline to BAU levels in the long run. The worst scenario declined all indicators below BAU levels. The four case studies were impacted in the same direction but to different extent, farms oriented to fattened calves suffered higher impacts than those focused on weaned calves. Traditional adaptation actions succeeded to maintain cow body condition score steady, but they came at the expense of lower feed self-sufficiency and gross margin, becoming impractical to face climate change. [ABSTRACT FROM AUTHOR]

Livestock systems contribution to environmental change is controversial. Pasture-based systems are considered a sustainable alternative due to their adaptation to the use of local natural resources. However, they have limited productivity per product unit and, in Europe, depend on public economic support. Furthermore, they are heterogeneous in farm structure and resources use, which may determine their sustainability. We use emergy accounting to assess the sustainability of mountain pasture-based cattle systems and analyse the variability among farms. Emergy accounting assesses the sustainability performance of complex systems (i.e., farming systems) and their interaction with other systems (i.e., the environment and the socio-economic system) focusing on the origin, quality and quantity of the energy required for the system to function. Results show that pasture-based systems largely use local natural renewable resources but depend largely on the wider socio-economic system given their reliance on public economic support and purchased animal feeds. This economic dependence turns out in most farms largely using non-renewable resources. Increasing self-produced feeds and grazing on natural pastures can reduce the dependence on the socio-economic system and improve farm sustainability. [ABSTRACT FROM AUTHOR]

In this paper we prove that for any p ∈ [2,∞) the ℓ p n unit ball, B p n , satisfies the square negative correlation property with respect to every orthonormal basis, while we show it is not always the case for 1 ≤ p ≤ 2. In order to do that we regard B p n as the orthogonal projection of B p n + 1 onto the hyperplane e n + 1 ⊥ . We will also study the orthogonal projection of B p n onto the hyperplane orthogonal to the diagonal vector (1, ..., 1). In this case, the property holds for all p ≥ 1 and n large enough. [ABSTRACT FROM AUTHOR]

Linker histone H1 is an important structural component of chromatin that stabilizes the nucleosome and compacts the nucleofilament into higher-order structures. The biology of histone H1 remains, however, poorly understood. Here we show that Drosophila histone H1 (dH1) prevents genome instability as indicated by the increased 947H2Av (H2AvS137P) content and the high incidence of DNA breaks and sister-chromatid exchanges observed in dH1- depleted cells. Increased 947H2Av occurs preferentially at heterochromatic elements, which are upregulated upon dH1 depletion, and is due to the abnormal accumulation of DNA:RNA hybrids (R-loops). R-loops accumulation is readily detectable in G1-phase, whereas 947H2Av increases mainly during DNA replication. These defects induce JNK-mediated apoptosis and are specific of dH1 depletion since they are not observed when heterochromatin silencing is relieved by HP1a depletion. Altogether, our results suggest that histone H1 prevents R-loopsinduced DNA damage in heterochromatin and unveil its essential contribution to maintenance of genome stability. [ABSTRACT FROM AUTHOR]

We give criteria of total incomparability for certain classes of mixed Tsirelson spaces. We show that spaces of the form with index finite are either c0 or saturated for some p and we characterize when any two spaces of such a form are totally incomparable in terms of the index and the parameter θk. Also, we give sufficient conditions of total incomparability for a particular class of spaces of the form in terms of the asymptotic behaviour of the sequence where (ei is the canonical basis. [ABSTRACT FROM AUTHOR]

The L-myc restriction fragment length polymorphism has been suggested to be of prognostic significance in some types of primary tumours. We examined the prognostic and susceptibility significance of the L-myc genotype in a group of 98 bladder cancer patients. The L-myc genotype did not correlate with any pathologic parameter and does not offer any clinical utility in patients with bladder cancer. [ABSTRACT FROM AUTHOR]

An extracellular β-glucanase from Bacillus licheniformis has been isolated and characterized. Isolation has been performed by salting out and gel filtration chromatography, yielding a homogeneous active component with a molecular mass of 27 000-28 000 daltons and an isoelectric point of 4.7. In addition to being quite a thermostable protein (optimal temperature 55°C) the enzyme is active under a wide range of conditions including pH (4.0-10.5), and in the presence of a large number of metal ions, sodium dodecylsulphate and ethylenediaminetetraacetate. The simple purification procedure and useful properties make this enzyme suitable for brewing processes. [ABSTRACT FROM AUTHOR]

PhoB is a two-component response regulator that activates transcription by interacting with the ?70 subunit of the E. coli RNA polymerase in promoters in which the ?35 ?70-recognition element is replaced by the pho box. The crystal structure of a transcription initiation subcomplex that includes the ?4 domain of ?70 fused with the RNA polymerase ? subunit flap tip helix, the PhoB effector domain and the pho box DNA reveals how ?4 recognizes the upstream pho box repeat. As with the ?35 element, ?4 achieves this recognition through the N-terminal portion of its DNA recognition helix, but contact with the DNA major groove is less extensive. Unexpectedly, the same recognition helix contacts the transactivation loop and helices ?2 and ?3 of PhoB. This result shows a simple and elegant mechanism for polymerase recruitment to pho box promoters in which the lost ?35 element contacts are compensated by new ones with the activator. In addition, ?4 is reoriented, thereby suggesting a remodelling mechanism for transcription initiation. [ABSTRACT FROM AUTHOR]