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The discovery of a site with abundant fossil plant remains in the surroundings of Aguilar de Campoo (Palencia, Spain), dated in the early Holocene, allowed us to obtain new data on the composition of foreste in that área. Two species of Pinus and several broadleaved trees have been identified. A wider distribution than the current one for some of these taxa has been confirmed. The ecological requirements of these species today allow the probable Palaeoecological conditions during the Holocene to be established.

This paper reports results of work at the Cevico Navero site in Palencia, Spain. Macro- and microscopic study of the subfossil cones and trunks found at the site has permitted their identification to the species Pinus nigra. Radiocarbon dating of the wood indicates that this pine species was present in the región 3,500 years ago. The results are discussed in the context of other relevant literature. The dynamics of vegetation cover in the study área and the paleochorology of P. nigra are considered.

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El presente trabajo analiza el futuro modelo de información corporativa, el informe integrado, que aúna en uno solo toda la información necesaria para evaluar el verdadero valor de la empresa y su impacto en la sociedad. Además se estudia la necesaria evolución de la actividad de la auditoría para dar respuesta a las expectativas de los grupos de interés sobre la seguridad y fiabilidad de la información no financiera contenida en el informe integrado. Con este objeto se han analizado los informes integrados de dos entidades, así como los informes que sobre los mismos han emitido los auditores.

Cet article analyse les circonstances de l'arrivée de la matière de Bretagne dans la péninsule ibérique. Cette matière est davantage développée dans les compilations historiographiques que dans les œuvres de fiction car sa vraisemblance est soutenue par l'intérêt pour l'histoire de l'Antiquité qui se renforce dans la seconde moitié du XIIIe siècle. Ce processus est manifeste dans la General estoria, chronique universelle où sont versés les premiers éléments de l'Historia regum Britanniae de Geoffreoy de Monmouth, depuis l'histoire de Brutus jusqu'à Jules César. Nous traitons ici de l'un des manuscrits espagnols contenant l'Historia, le manuscrit BNE 6319, comparons le récit qu'il offre à la traduction alphonsine, et observons comment les faits narrés dans l'Historia deviennent d'utiles leçons politiques, faciles à relier aux problèmes auxquels le roi Sage fut confronté.

The Orinoco crocodile (Crocodylus intermedius) is a resource that was exploited by indigenous and creole populations from the Orinoco Llanos in past centuries for food, medicine, and mystical and cultural traditions. These uses and the speciesâ former abundance were exposed through the works of voyagers and adventurers who traveled through the Orinoco basin between the 17th Century and the beginning of the 20th Century. Settlement and the development of agricultural and cattle raising activities increased the perception of the species as a threat to human interests. At the beginning and middle of the 20th Century, the crocodile was intensively exploited for the trade of its skin. This situation provoked the near extinction of the species. At present, despite its critical situation, its eggs continue to be collected for consumption in nearly all known wild populations where reproductive events occur. This activity, joined with capture of hatchlings and juveniles, premeditated or accidental deaths of specimens, habitats destruction, and the possible changes in the natural hydrological dynamics, are preventing its recovery or even reducing the populations in the wild.

The Arrau river turtle or giant South American turtle (Podocnemis expansa) and the yellow-spotted river turtle (Podocnemis unifilis) have wide distributions within the Orinoco and Amazon River basins. Both of them have been exploited since pre-colonial times as a protein source by indigenous groups, and have also played an important cultural role. The chroniclers that traveled these wide regions between the 18th and beginning of the 20th centuries recorded evidence of their abundance, traditional uses, hunting methods, changes in processes and intensity of exploitation, and sociocultural and socioeconomic importance. We present a compilation of traditional uses from local human communities as well as an analysis of its impact on the conservation of both species. Also, we put forth a general review of the uses and capture methods for these species in the last few decades, which reveal the important role that they still play among the indigenous and rural communities.

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Anticancer topoisomerase "poisons" exploit the break-and-rejoining mechanism of topoisomerase II (TOP2) to generate TOP2-linked DNA double-strand breaks (DSBs). This characteristic underlies the clinical efficacy of TOP2 poisons, but is also implicated in chromosomal translocations and genome instability associated with secondary, treatment-related, haematological malignancy. Despite this relevance for cancer therapy, the mechanistic aspects governing repair of TOP2-induced DSBs and the physiological consequences that absent or aberrant repair can have are still poorly understood. To address these deficits, we employed cells and mice lacking tyrosyl DNA phosphodiesterase 2 (TDP2), an enzyme that hydrolyses 5'-phosphotyrosyl bonds at TOP2-associated DSBs, and studied their response to TOP2 poisons. Our results demonstrate that TDP2 functions in non-homologous end-joining (NHEJ) and liberates DSB termini that are competent for ligation. Moreover, we show that the absence of TDP2 in cells impairs not only the capacity to repair TOP2-induced DSBs but also the accuracy of the process, thus compromising genome integrity. Most importantly, we find this TDP2-dependent NHEJ mechanism to be physiologically relevant, as Tdp2-deleted mice are sensitive to TOP2-induced damage, displaying marked lymphoid toxicity, severe intestinal damage, and increased genome instability in the bone marrow. Collectively, our data reveal TDP2-mediated error-free NHEJ as an efficient and accurate mechanism to repair TOP2-induced DSBs. Given the widespread use of TOP2 poisons in cancer chemotherapy, this raises the possibility of TDP2 being an important etiological factor in the response of tumours to this type of agent and in the development of treatment-related malignancy.

During 2010 and 2011 diurnal and nocturnal surveys were conducted in the drainages of the Meta and Vichada rivers (Colombian Orinoco Basin) to update the information about the conservation status of the Orinoco crocodileâs populations in the wild. Between November 2010 and March 2011 stretches of six watercourses of the Meta river Basin and a stretch of the Vichada river were sampled, covering 2460.3 km, and 199.2 km of nocturnal censuses were traveled. Six observations were made in the Vichada river, corresponding to two individuals (one seen twice, the other seen four times) and crocodile tracks were found on two beaches. Additionally, territorial behavior of one of the individuals observed was registered. No crocodiles were seen in the stretches of the Meta River, or any of its tributaries surveyed. Apparently, the populations in the areas studied have not recovered since 1994-1997, the last time data were obtained, probably due to the annual plundering of nests, the destruction of habitat and the accidental or deliberate death of individuals.

Rebound of HIV viremia after interruption of anti-retroviral therapy is due to the small population of CD4+ T cells that remain latently infected. HIV-1 transcription is the main process controlling post-integration latency. Regulation of HIV-1 transcription takes place at both initiation and elongation levels. Pausing of RNA polymerase II at the 5' end of HIV-1 transcribed region (5'HIV-TR), which is immediately downstream of the transcription start site, plays an important role in the regulation of viral expression. The activation of HIV-1 transcription correlates with the rearrangement of a positioned nucleosome located at this region. These two facts suggest that the 5'HIV-TR contributes to inhibit basal transcription of those HIV-1 proviruses that remain latently inactive. However, little is known about the cell elements mediating the repressive role of the 5'HIV-TR. We performed a genetic analysis of this phenomenon in Saccharomyces cerevisiae after reconstructing a minimal HIV-1 transcriptional system in this yeast. Unexpectedly, we found that the critical role played by the 5'HIV-TR in maintaining low levels of basal transcription in yeast is mediated by FACT, Spt6, and Chd1, proteins so far associated with chromatin assembly and disassembly during ongoing transcription. We confirmed that this group of factors plays a role in HIV-1 postintegration latency in human cells by depleting the corresponding human orthologs with shRNAs, both in HIV latently infected cell populations and in particular single-integration clones, including a latent clone with a provirus integrated in a highly transcribed gene. Our results indicate that chromatin reassembly factors participate in the establishment of the equilibrium between activation and repression of HIV-1 when it integrates into the human genome, and they open the possibility of considering these factors as therapeutic targets of HIV-1 latency.