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Objective. The present article approaches in a succinct way to some theoretical considerations about the preservation and the risk management in digital repositories. In that sense, three key international experiences are presented, in order to assess risks in the digital environment and to offer a set of general requirements that should be taken into account for the assessment of preservation risks in digital repositories. Method. We used the classic documentary analysis of an extensive specialized bibliography on the subject. Likewise, the classic documentary analysis was very useful for the understanding of the three international experiences of risk assessment in digital repositories that are presented. Results. The main result was a set of ten general requirements that should be taken into account for the assessment of preservation risks in digital repositories. Conclusions. The results obtained make it possible to assess the reliability, authenticity and integrity of your resources through the identification of threats in the components of your system, your community of users and your organizational environment.

In the Mediterranean, mixed forests of Aleppo pine and holm oak are widespread. Generally considered a transition stage in the succession towards climax oak communities, niche segregation may also contribute to the prevalence of these communities. So far, there is increasing evidence of hydrological niche segregation, with the two species showing complementary water use and seasonal growth patterns. However, it remains unknown whether interspecific interactions affect the response to climate and the mid-term (decadal) growth and water-use efficiency of pines and oaks in mixed stands. Here, we combined tree-ring chronologies, built on different competition classes within a mixed stand, with a spatially explicit assessment of individual growth and wood carbon isotope discrimination (∆13C), as a proxy of intrinsic water-use efficiency, and compared these results with previously reported water uptake patterns. We found that competition with pines modulated the climate response of oaks, whereas pine climate response was insensitive to competition. On the other hand, pine density affected only pine growth, whereas oak competition affected both species. We conclude that the presence of pines had negligible or even positive effects on the oaks, but competition with neighbor oaks limited their ability to recover after drought. Conversely, pines experienced greater drought stress under competition, with both oaks and pines This research was funded by the Spanish Government through Projects CGL2011-26654 and RTI2018-094691-B-C31 (MCIU/AEI/FEDER, EU). J.P.F. was supported by Reference Group H09_20R (Gobierno de Aragón, Spain).

This chapter briefly develops how Latin American countries, with a special focus on Peru, execute political protection of its interests since it is with the important support of the state that they can promote the defence of denominations of origin, the protection of genetic resources and traditional knowledge, access government backed foreign direct investment initiatives and benefit from export credit agencies. These types of political protection do not pretend to be fully comprehensive but contribute to knowing which are currently in place in the countries mentioned. After reading this document, students have clarity about four main tools for state protection of local Peruvian products abroad and know about other international cases regarding similar protection.

Currently, documentary assessment is one of the most controversial processes in archival science because of its implications from an informational, political and social point of view. Although the background of this process dates back to medieval times, it would be inaccurate to speak about some theoretical systematization before Americans Philip Brooks and Theodore Schellenberg's contributions in the 40s and 50s in the 20th century. In the light of the post custodial paradigm, the assessment of archival documents has been the object of increasing theoretical reflections, which has led to different positions. This article intends to perform an approach to archival document assessment based on custodial and post custodial paradigms. To that effect, it addresses some of the aspects which have been the subject of questioning in both cases. Afterwards, this article presents a macro assessment analysis and its fundamental characteristics.

The potential of the vegetation to sequester C is determined by the balance between assimilation and respiration. Respiration is under environmental and substrate-driven control, but the circadian clock might also contribute. To assess circadian control on night-time dark respiration (RD) and on light enhanced dark respiration (LEDR) - the latter providing information on the metabolic reorganization in the leaf during light-dark transitions - we performed experiments in macrocosms hosting canopies of bean and cotton. Under constant darkness (plus constant air temperature and air humidity), we tested whether circadian regulation of RD scaled from leaf to canopy respiration. Under constant light (plus constant air temperature and air humidity), we assessed the potential for leaf-level circadian regulation of LEDR. There was a clear circadian oscillation of leaf-level RD in both species and circadian patterns scaled to the canopy. LEDR was under circadian control in cotton, but not in bean indicating species-specific controls. The circadian rhythm of LEDR in cotton might indicate variable suppression of the normal cyclic function of the tricarboxylic-acid-cycle in the light. Since circadian regulation is assumed to act as an adaptive memory to adjust plant metabolism based on environmental conditions from previous days, circadian control of RD may help to explain temporal variability of ecosystem respiration. This study benefited from the CNRS human and technical resources allocated to the ECOTRONS Research Infrastructures as well as from the state allocation ‘Investissement d'Avenir’ AnaEE-France ANR-11-INBS-0001, ExpeER Transnational Access program, Ramón y Cajal fellowships (RYC-2012-10970 to VRD and RYC-2008-02050 to JPF), the Erasmus Mundus Master Course MEDfOR, internal grants from UWS-HIE to VRD and ZALF to AG and Juan de la Cierva-fellowships (IJCI-2014-21393 to JGA). We remain indebted to E. Gerardeau, D. Dessauw, J. Jean, P. Prudent (Aïda CIRAD), J.-J. Drevon, C. Pernot (Eco&Sol INRA), B. Buatois, A. Rocheteau (CEFE CNRS), A. Pra, A. Mokhtar and the full Ecotron team, in particular C. Escape, for outstanding technical assistance.

Studies on the dependence of the rates of ecosystem gas exchange on environmental parameters often rely on the up-scaling of leaf-level response curves ('bottom-up' approach), and/or the down-scaling of ecosystem fluxes ('top-down' approach), where one takes advantage of the natural diurnal covariation between the parameter of interest and photosynthesis rates. Partly independent from environmental variation, molecular circadian clocks drive ∼24 h oscillations in leaf-level photosynthesis, stomatal conductance and other physiological processes in plants under controlled laboratory conditions. If present and of sufficient magnitude at ecosystem scales, circadian regulation could lead to different results when using the bottom-up approach (where circadian regulation exerts a negligible influence over fluxes because the environment is modified rapidly) relative to the top-down approach (where circadian regulation could affect fluxes as it requires the passage of a few hours). Here we dissected the drivers of diurnal net CO2 exchange in canopies of an annual herb (bean) and of a perennial shrub (cotton) through a set of experimental manipulations to test for the importance of circadian regulation of net canopy CO2 exchange, relative to that of temperature and vapor pressure deficit, and to understand whether circadian regulation could affect the derivation of environmental flux dependencies. Contrary to conventional wisdom, we observed how circadian regulation exerted controls over net CO2 exchange that were of similar magnitude to the controls exerted by direct physiological responses to temperature and vapor pressure deficit. Diurnal patterns of net CO2 exchange could only be explained by considering effects of environmental responses combined with circadian effects. Consequently, we observed significantly different results when inferring the dependence of photosynthesis over temperature and vapor pressure deficit when using the top-down and the bottom up approaches. We remain indebted to E. Gerardeau, D. Dessauw, J. Jean, P. Prudent (Aïda CIRAD), J.-J. Drevon, C. Pernot (Eco&Sol INRA), B. Buatois, A. Rocheteau (CEFE CNRS), A. Pra, A. Mokhtar and the full Ecotron team, in particular C. Escape, for outstanding technical assistance during experiment set-up, plant cultivation and measurements. Earlier versions of the manuscript benefitted from comments by M. Dietze, B. Medlyn, R. Duursma and Y.-S. Lin. This study benefited from the CNRS human and technical resources allocated to the ECOTRONS Research Infrastructures as well as from the state allocation ‘Investissement d'Avenir’ ANR-11-INBS-0001, ExpeER Transnational Access program, Ramón y Cajal fellowships (RYC-2012-10970 to VRD and RYC-2008-02050 to JPF), the Erasmus Mundus Master Course Mediterranean Forestry and Natural Resources Management (MEDfOR) and internal grants from UWS-HIE to VRD and ZALF to AG. We thank the Associate Editor T. Vesala and two anonymous reviewers for their help to improve this manuscript.

A common pattern in Aleppo pine Δ 13 C responses to both spatial and temporal variability in precipitation was observed, with a general agreement between NDVI, Δ 13 C and growth that confirms precipitation as key environmental driver. The aim of this study was to assess the spatiotemporal variability of carbon isotope discrimination (Δ13C) records and its relationship with radial growth (RG) and Normalized Difference Vegetation Index (NDVI) data using a tree-ring network of Aleppo pine (Pinus halepensis Mill.) in the eastern part of the Iberian Peninsula. For this purpose, we collected a biennial time series of Δ13C (1949–1998), together with mean annual precipitation, tree-ring width, and remote sensing (NDVI) data for seven locations along a precipitation gradient. We evaluated how intra-site correlations between variables changed across locations, and how inter-site (or spatial) correlations changed across years. We found that correlations between Δ13C and precipitation were higher in dry than in wet sites, in agreement with previous studies. Mean RG and NDVI were good indicators of site-specific Δ13C sensitivity to precipitation. The strongest spatial associations between Δ13C and precipitation were also found during the driest biennia. However, spatial correlations were strongly affected by carryover effects of extreme events. Overall, we found a good agreement between Δ13C, NDVI, and RG, although they showed different response patterns to precipitation. We suggest that the combination of these proxies may be useful for monitoring changes in water-use efficiency and productivity at the regional level.

Background Molecular clocks drive oscillations in leaf photosynthesis, stomatal conductance, and other cell and leaf-level processes over ~24 h under controlled laboratory conditions. The influence of such circadian regulation over whole-canopy fluxes remains uncertain; diurnal CO2 and H2O vapor flux dynamics in the field are currently interpreted as resulting almost exclusively from direct physiological responses to variations in light, temperature and other environmental factors. We tested whether circadian regulation would affect plant and canopy gas exchange at the Montpellier European Ecotron. Canopy and leaf-level fluxes were constantly monitored under field-like environmental conditions, and under constant environmental conditions (no variation in temperature, radiation, or other environmental cues). Results We show direct experimental evidence at canopy scales of the circadian regulation of daytime gas exchange: 20–79 % of the daily variation range in CO2 and H2O fluxes occurred under circadian entrainment in canopies of an annual herb (bean) and of a perennial shrub (cotton). We also observed that considering circadian regulation improved performance by 8–17 % in commonly used stomatal conductance models. Conclusions Our results show that circadian controls affect diurnal CO2 and H2O flux patterns in entire canopies in field-like conditions, and its consideration significantly improves model performance. Circadian controls act as a ‘memory’ of the past conditions experienced by the plant, which synchronizes metabolism across entire plant canopies. Electronic supplementary material The online version of this article (doi:10.1186/s13742-016-0149-y) contains supplementary material, which is available to authorized users.

[1] Stable isotopes in tree rings provide climatic information with annual resolution dating back for centuries or even millennia. However, deriving spatially explicit climate models from isotope networks remains challenging. Here we propose a methodology to model regional precipitation from carbon isotope discrimination (Δ13C) in tree rings by (1) building regional spatial models of Δ13C (isoscapes) and (2) deriving precipitation maps from Δ13C-isoscapes, taking advantage of the response of Δ13C to precipitation in seasonally dry climates. As a case study, we modeled the spatial distribution of mean annual precipitation (MAP) in the northeastern Iberian Peninsula, a region with complex topography and climate (MAP = 303–1086 mm). We compiled wood Δ13C data for two Mediterranean species that exhibit complementary responses to seasonal precipitation (Pinus halepensis Mill., N = 38; Quercus ilex L.; N = 44; pooling period: 1975–2008). By combining multiple regression and geostatistical interpolation, we generated one Δ13 C-isoscape for each species. A spatial model of MAP was then built as the sum of two complementary maps of seasonal precipitation, each one derived from the corresponding Δ13C-isoscape (September–November from Q. ilex; December–August from P. halepensis). Our approach showed a predictive power for MAP (RMSE = 84 mm) nearly identical to that obtained by interpolating data directly from a similarly dense network of meteorological stations (RMSE = 80–83 mm, N = 65), being only outperformed when using a much denser meteorological network (RMSE = 56–57 mm, N = 340). This method offers new avenues for modeling spatial variability of past precipitation, exploiting the large amount of information currently available from tree-ring networks.

Molecular clocks drive oscillations in leaf photosynthesis, stomatal conductance and other cell and leaf level processes over ~24 h under controlled laboratory conditions. The influence of such circadian regulation over whole canopy fluxes remains uncertain and diurnal CO2and H2O vapor flux dynamics in the field are currently interpreted as resulting almost exclusively from direct physiological responses to variations in light, temperature and other environmental factors. We tested whether circadian regulation would affect plant and canopy gas exchange at the CNRS Ecotron. Canopy and leaf level fluxes were constantly monitored under field-like environmental conditions, and also under constant environmental conditions (no variation in temperature, radiation or other environmental cues). Here we show first direct experimental evidence at canopy scales of circadian gas exchange regulation: 20-79% of the daily variation range in CO2and H2O fluxes occurred under circadian entrainment in canopies of an annual herb (bean) and of a perennial shrub (cotton). We also observed that considering circadian regulation improved performance in commonly used stomatal conductance models. Overall, our results show that overlooked circadian controls affect diurnal patterns of CO2and H2O fluxes in entire canopies and in field-like conditions, although this process is currently unaccounted for in models.

Understanding inter- and intra-specific plant interactions and competition over water is challenging because of the lack of effective approaches for accessing and monitoring root distribution and activity. In this context, stable isotopes are excellent co-hydrological tracers that allow characterizing the dynamics of water uptake patterns in trees and shrubs. Here, we studied biotic interactions for wateruptake between two typical Mediterranean tree species, Aleppo pine (Pinus halepensis ) and holm oak ( Quercus ilex), coexisting in a mixed forest. We measured stable isotope composition ( d1 8O and d2H) of xylem water in all trees found in the studied stand during one growing season, covering an exception- ally long summer drought and subsequent recovery. We applied point-process statistics together with stand density information to evaluate tree-to-tree interactions for water use. In pines, we observed a clear uncoupling between soil and xylem water isotope composition after two months of persistent drought. Conversely, the isotope composition of xylem water in oaks tracked observed changes in the soil during the first two months of drought, but began to depart from soil values after three months. These results suggest that during drought the oaks were able to keep active for longer using alternative soil water sources, not available for the pines. Point-process statistics revealed more positive isotope compo- sitions at distances below 4–6 m, but only between con-specific individuals (i.e. pine-pine, oak-oak). These intra-specific responses were first seen in the pines (after two months of drought) and subse- quently in oaks (after three months), coinciding with the onset of soil-xylem uncoupling for each species. On the other hand, the isotope composition of individual oaks decreased with increasing neighbor pine density, but increased in response to oak density. Conversely, the pines showed more positive values with increasing oak density. Our results suggest that the use of shallow water in oaks is limited by the pres- ence of pines, which force them to shift to deep-soil water use, whereas pines have more restricted access to deep water in the presence of oaks, leading to more positive isotope values. According to the dynamics of interaction patterns, we conclude that inter-specific differences in pine-oak mixed forests hold two components: a static, spatial component determined by root distribution, and a dynamic, physiological component related to water uptake capacity within the soil profile. We acknowledge the financial support by the Spanish Ministry of Economy and Competitiveness, through a FPI fellowship to J.d.C. (BES-2010-0324572-01), a contract through the Ramón y Cajal programme to J.P.F. (RYC-2008-02050), and the research project CGL2011-26654.

The following is a case of Charles Bonnet syndrome in an 86-year-old woman who presented with visualhallucinations. The differential diagnosis of visual hallucinations is broad and emergency physicians shouldbe knowledgeable of the possible etiologies. [West J Emerg Med. 2012;13(6):544-547]

Aim of study: Understanding inter- and intra-specific competition for water is crucial in drought-prone environments. However, little is known about the spatial interdependencies for water uptake among individuals in mixed stands. The aim of this work was to compare water uptake patterns during a drought episode in two common Mediterranean tree species, Quercus ilex L. and Pinus halepensis Mill., using the isotope composition of xylem water (δ18O, δ2 H) as hydrological marker. Area of study: The study was performed in a mixed stand, sampling a total of 33 oaks and 78 pines (plot area= 888 m2 ). We tested the hypothesis that both species uptake water differentially along the soil profile, thus showing different levels of tree-to-tree interdependency, depending on whether neighbouring trees belong to one species or the other. Material and Methods: We used pair-correlation functions to study intra-specific point-tree configurations and the bivariate pair correlation function to analyse the inter-specific spatial configuration. Moreover, the isotopic composition of xylem water was analysed as a mark point pattern. Main results: Values for Q. ilex (δ18O = –5.3 ± 0.2‰, δ2 H = –54.3 ± 0.7‰) were significantly lower than for P. halepensis (δ18O = –1.2 ± 0.2‰, δ2 H = –25.1 ± 0.8‰), pointing to a greater contribution of deeper soil layers for water uptake by Q. ilex. Research highlights: Point-process analyses revealed spatial intra-specific dependencies among neighbouring pines, showing neither oak-oak nor oak-pine interactions. This supports niche segregation for water uptake between the two species. This work was funded by the Projects SMARTREES (FP7-PEOPLE-2009-RG-246725, EU) and RESILFOR (AGL 2012-40039-C02-02, MEC, and Spain). JPF and JdC were supported by the Ramon y Cajal programme (MEC, Spain), and a FPI fellowship (MEC, Spain), respectively.

Two patients with injuries to the ankle sustained by rotational trauma complained only of pain in the ankle. Careful examination revealed tenderness over the proximal fibula. Subsequent radiographic studies revealed high helical fracture of the fibula, as originally described by Maisonneuve. The Maisonneuve fracture is produced by diastasis - a separation of bones resulting from rupture of ligaments around the ankle. According to classification of fibula injuries by mechanism of injury, the Maisonneuve fracture is due to external rotation of the foot relative to the tibia but it is not clear whether the foot is in pronation or supination or moves during injury.