1,508 research outputs found
Seed germination of six Iberian endemic species – a contribution to enhance plant conservation
Biodiversity has been degraded all around the world due to anthropogenic factors. To counteract this
worldwide tendency, ecological restoration programs are expanding. In these programs, the use of
native herbaceous species, particularly those endemic or threatened, can be promoted by seeding
them but germination requirements for most of these species are unknown. Our research meant to fill
this gap of information for six Iberian endemic species suitable to use in restoration actions - Digitalis
thapsi, Ferula communis subsp. catalaunica, Linaria amethystea subsp. amethystea, Pterocephalidium
diandrum, Sanguisorba hybrida, and Silene scabriflora subsp. scabriflora. Their seed germination behaviour
was analysed to establish germination protocols for conservation actions. Three germination conditions
were used to simulate different sown seasons. Seeds of all species were tested without pretreatment
and subjected to a cold stratification. Seeds of S. hybrida and P. diandrum were additionally
tested with a scarification treatment. All species reached their better germination performance under
autumn conditions (15/10 C; 8/16 hours). In conclusion, for all the six Iberian endemic species tested,
germination speed and percentage were suitable for their use in native plants reinforcement
Best Pratice Guide to Manage Vegetation and Promote Biodiversity in Linear Infrastructures
The present guide is based on the experience acquired in the framework of the LIFE LINES project (LIFE14 NAT/PT/001081) and intends to compile and disseminate the recommendable procedures for the management of biodiversity, particularly of plant diversity, in the marginal areas of linear infrastructures, primarily focusing on the national roads, decommissioned railways now used for recreation purposes (ecotrails) and power lines of very high voltage. The guide includes technical information for those in charge of the management of roads, trails and power lines (concession holders, municipalities), for environmental consultancy (Agência Portuguesa do Ambiente, Instituto de Conservação da Natureza e Florestas), and for landscape and agroforestry technicians, as well as for the general public
Photocatalytic behavior of phosphonate-based hybrid materials on dyes and phenols degradation
Comunicación presentanda al congreso EUROMAT2013, del 8 al 13 de Septiembre, Sevilla.There is increasing interest in using heterogeneous catalysis for mineralization of
organic pollutants. Within Advanced Oxidation Processes (AOPs), Photo-Fenton
reaction is one of the most efficient methodologies. To date, most of heterogeneous
iron catalysts studied was based on oxides or hydroxides. We extend here our previous
studies on phenol photodegradation [1] by exploring the photocatalytic activity of
various hybrid MII phosphonates (MII = Mn, Fe, Cu) for several organic pollutants.
Synthesis conditions, pre-activation, H2O2 concentration, and surface characteristic have
been studied/optimized. For dyes, decolouring and mineralization degrees up to 90%
and 45%, respectively, were attained. Chemical analysis and X-ray photoelectron
spectroscopy revealed the dynamic character of the photocatalyst surface upon reaction.MAT2010-15175; FQM-11
Guião de Boas Práticas de Gestão da Vegetação para a Promoção e Biodiversidade em Infraestruturas Lineares
O presente guião de boas práticas tem por base a experiência
adquirida ao longo do projeto LIFE LINES (LIFE14 NAT/PT/001081),
pretendendo reunir e divulgar procedimentos recomendáveis para a
gestão da biodiversidade, com ênfase na diversidade vegetal das zo nas marginais associadas às infraestruturas lineares, e focando-se, so bretudo, em estradas nacionais, ferrovias desativadas com uso recrea tivo (ecopistas) e linhas elétricas de muito alta tensão.
O guião inclui informação técnica dirigida às entidades gestoras de
estradas, caminhos pedestres e de linhas de muito alta tensão (con cessionárias, autarquias), a responsáveis pela Avaliação de Impacte
Ambiental de infraestruturas lineares (Agência Portuguesa do Ambien te, Instituto de Conservação da Natureza e Florestas), a técnicos da
área do paisagismo e operações agroflorestais, bem como informação
dirigida ao público em geral
On the exact gravitational lens equation in spherically symmetric and static spacetimes
Lensing in a spherically symmetric and static spacetime is considered, based
on the lightlike geodesic equation without approximations. After fixing two
radius values r_O and r_S, lensing for an observation event somewhere at r_O
and static light sources distributed at r_S is coded in a lens equation that is
explicitly given in terms of integrals over the metric coefficients. The lens
equation relates two angle variables and can be easily plotted if the metric
coefficients have been specified; this allows to visualize in a convenient way
all relevant lensing properties, giving image positions, apparent brightnesses,
image distortions, etc. Two examples are treated: Lensing by a
Barriola-Vilenkin monopole and lensing by an Ellis wormhole.Comment: REVTEX, 11 pages, 12 eps-figures, figures partly improved, minor
revision
Inhibition of the PP2A activity by the histone chaperone ANP32B is long-range allosterically regulated by respiratory cytochrome c
Repair of injured DNA relies on nucleosome dismantling by histone chaperones and de-phosphorylation events carried out by Protein Phosphatase 2A (PP2A). Typical histone chaperones are the Acidic leucine-rich Nuclear Phosphoprotein 32 family (ANP32) members, e.g. ANP32A, which is also a well-known PP2A inhibitor (a.k.a. I1PP2A). Here we report the novel interaction between the endogenous family member B—so-called ANP32B—and endogenous cytochrome c in cells undergoing camptothecin-induced DNA damage. Soon after DNA lesions but prior to caspase cascade activation, the hemeprotein translocates to the nucleus to target the Low Complexity Acidic Region (LCAR) of ANP32B; in a similar way, our group recently reported that the hemeprotein targets the acidic domain of SET/Template Activating Factor-Iß (SET/TAF-Iß), which is another histone chaperone and PP2A inhibitor (a.k.a. I2PP2A). The nucleosome assembly activity of ANP32B is indeed unaffected by cytochrome c binding. Like ANP32A, ANP32B inhibits PP2A activity and is thus herein referred to as I3PP2A. Our data demonstrates that ANP32B-dependent inhibition of PP2A is regulated by respiratory cytochrome c, which induces long-distance allosteric changes in the structured N-terminal domain of ANP32B upon binding to the C-terminal LCAR. In agreement with the reported role of PP2A in the DNA damage response, we propose a model wherein cytochrome c is translocated from the mitochondria into the nucleus upon DNA damage to modulate PP2A activity via its interaction with ANP32B. © 2021 The Author(s
Higher Order Evaluation of the Critical Temperature for Interacting Homogeneous Dilute Bose Gases
We use the nonperturbative linear \delta expansion method to evaluate
analytically the coefficients c_1 and c_2^{\prime \prime} which appear in the
expansion for the transition temperature for a dilute, homogeneous, three
dimensional Bose gas given by T_c= T_0 \{1 + c_1 a n^{1/3} + [ c_2^{\prime}
\ln(a n^{1/3}) +c_2^{\prime \prime} ] a^2 n^{2/3} + {\cal O} (a^3 n)\}, where
T_0 is the result for an ideal gas, a is the s-wave scattering length and n is
the number density. In a previous work the same method has been used to
evaluate c_1 to order-\delta^2 with the result c_1= 3.06. Here, we push the
calculation to the next two orders obtaining c_1=2.45 at order-\delta^3 and
c_1=1.48 at order-\delta^4. Analysing the topology of the graphs involved we
discuss how our results relate to other nonperturbative analytical methods such
as the self-consistent resummation and the 1/N approximations. At the same
orders we obtain c_2^{\prime\prime}=101.4, c_2^{\prime \prime}=98.2 and
c_2^{\prime \prime}=82.9. Our analytical results seem to support the recent
Monte Carlo estimates c_1=1.32 \pm 0.02 and c_2^{\prime \prime}= 75.7 \pm 0.4.Comment: 29 pages, 3 eps figures. Minor changes, one reference added. Version
in press Physical Review A (2002
Dietary Fat Patterns and Outcomes in Acute Pancreatitis in Spain
Background/Objective: Evidence from basic and clinical studies suggests that unsaturated fatty acids (UFAs) might be relevant mediators of the development of complications in acute pancreatitis (AP). Objective: The aim of this study was to analyze outcomes in patients with AP from regions in Spain with different patterns of dietary fat intake.
Materials and Methods: A retrospective analysis was performed with data from 1,655 patients with AP from a Spanish prospective cohort study and regional nutritional data from a Spanish cross-sectional study. Nutritional data considered in the study concern the total lipid consumption, detailing total saturated fatty acids, UFAs and monounsaturated fatty acids (MUFAs) consumption derived from regional data and not from the patient prospective cohort. Two multivariable analysis models were used: (1) a model with the Charlson comorbidity index, sex, alcoholic etiology, and recurrent AP; (2) a model that included these variables plus obesity.
Results: In multivariable analysis, patients from regions with high UFA intake had a significantly increased frequency of local complications, persistent organ failure (POF), mortality, and moderate-to-severe disease in the model without obesity and a higher frequency of POF in the model with obesity. Patients from regions with high MUFA intake had significantly more local complications and moderate-to-severe disease; this significance remained for moderate-to-severe disease when obesity was added to the model.
Conclusions: Differences in dietary fat patterns could be associated with different outcomes in AP, and dietary fat patterns may be a pre-morbid factor that determines the severity of AP. UFAs, and particulary MUFAs, may influence the pathogenesis of the severity of AP
Particle motion in the field of a five-dimensional charged black hole
In this paper, we have investigated the geodesics of neutral particles near a
five-dimensional charged black hole using a comparative approach. The effective
potential method is used to determine the location of the horizons and to study
radial and circular trajectories. This also helps us to analyze the stability
of radial and circular orbits. The radius of the innermost stable circular
orbits have also been determined. Contrary to the case of massive particles for
which, the circular orbits may have up to eight possible values of specific
radius, we find that the photons will only have two distinct values for the
specific radii of circular trajectories. Finally we have used the dynamical
systems analysis to determine the critical points and the nature of the
trajectories for the timelike and null geodesics.Comment: 15 pages, accepted for publication in Astrophysics and Space Scienc
Rice-fish research and development in Asia
Joint proceedings of two international workshops on rice-fish farming systems research and development û one held in Ubon, Thailand, on 23-27 October 1988; and the other on 23-27 October 1989 in Nueva Ecija, Philippines; gathering country overviews, production systems, economic and biological interactions, research and extension programs, and on-station and on-farm research activities from Bangladesh, China, India, Indonesia, Korea, Malaysia, the Philippines, Thailand and Vietnam.Rice-fish culture, Integrated farming, Conferences, Asia,
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