877 research outputs found
Ensayo metodológico de planificación física de una autovía en el Estado Miranda (Venezuela)
Planning taking into account the environment is fundamental to develop the human and environmental potencial of a territory. Nevertheless, the lack of geographical information in Southamerica makes it difficult for developers to use this technique. This article describes an essay of planning a ficticious highway with this restriction. Planning models have been developed using Geographic Information Systems (GIS) not only for land aptitude, risks, quality, fragility and impact, but also for its integration in transport planning. The final aim has been to model a friction map for highways so that land aptitude is optimized and impact is minimized. In addition, a labour of teaching and I+D transfer has been established with various countries in SouthAmerica.La planificación física con base ecológica es fundamental para desarrollar el potencial ambiental y humano de un territorio. Sin embargo, en numerosas áreas de Latinoamérica hay carencias de información territorial que dificultan estos procedimientos. En esta línea, se ha realizado un ensayo metodológico de una planificación física de una autovía hipotética. Para ello se han realizado modelos en SIG (Sistemas de Información Geográfica) de capacidad territorial, riesgos, calidad, fragilidad e impacto ambiental, que se han integrado en una síntesis de planificación territorial. El objetivo final ha sido modelizar un mapa de impedancia o fricción frente a la autovía, para aplicar un algoritmo cost distance / cost path y obtener un trazado de autovía que optimizase la capacidad del territorio y minimizase el impacto ambiental. Se ha consolidado un aprendizaje y una primera transferencia I + D dirigida a la gestión territorial y a la toma de decisiones para diversos países de Latinoamérica
Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, un discomicete con incidencia en la truficultura e interés forestal
Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, a cup-shaped
ascomycete related with truffle cultures and afforestation. A casual finding of Sphaerosporella brunnea in some greenhouses from Spain, growing in connection with several ectomycorrhizal
plants, is reported. These plants were experimentally inoculated with low level inoculum of Tuber melanosporum. Sphaerosporella brunnea is described and illustrated, and its negative role
in truffle cultures and its possible utilization in burned are as recovery is emphasized.Se da cuenta del hallazgo casual, en unos viveros españoles de Sphaerosporella brunnea, formando micorrizas con plantas diversas, las cuales habían sido inoculadas
experimentalmente con niveles bajos de Tuber melanosporum. Se describe e ilustra esta especie,
al tiempo que se destaca su papel negativo en la truficultura y su posible utilización en la recuperación de áreas incendiadas
Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, un discomicete con incidencia en la truficultura e interés forestal
Se da cuenta del hallazgo casual, en unos viveros españoles de Sphaerosporella brunnea, formando micorrizas con plantas diversas, las cuales habían sido inoculadas
experimentalmente con niveles bajos de Tuber melanosporum. Se describe e ilustra esta especie,
al tiempo que se destaca su papel negativo en la truficultura y su posible utilización en la recuperación de áreas incendiadas.Sphaerosporella brunnea (Alb. et Schwein.) Svrcek et Kubicka, a cup-shaped
ascomycete related with truffle cultures and afforestation. A casual finding of Sphaerosporella brunnea in some greenhouses from Spain, growing in connection with several ectomycorrhizal
plants, is reported. These plants were experimentally inoculated with low level inoculum of Tuber melanosporum. Sphaerosporella brunnea is described and illustrated, and its negative role
in truffle cultures and its possible utilization in burned are as recovery is emphasized
A new tool to derive chemical abundances in Type-2 Active Galactic Nuclei
We present a new tool for the analysis of the optical emission lines of the
gas in the Narrow Line Region (NLR) around Active Galactic Nuclei (AGNs). This
new tool can be used in large samples of objects in a consistent way using
different sets of optical emission-lines taking into the account possible
variations from the O/H - N/O relation. The code compares certain observed
emission-line ratios with the predictions from a large grid of photoionization
models calculated under the most usual conditions in the NLR of AGNs to
calculate the total oxygen abundance, nitrogen-to-oxygen ratio and ionization
parameter. We applied our method to a sample of Seyfert 2 galaxies with optical
emission-line fluxes from the literature. Our results confirm the high
metallicity of the objects of the sample and provide consistent values with the
direct method. The usage of models to calculate precise ICFs is mandatory when
only optical emission lines are available to derive chemical abundances using
the direct method in NLRs of AGN.Comment: Proceedings paper of the IAU symposium "Nuclear Activity in Galaxies
Across Cosmic Time" (Ethiopia) accepted to be published under the Cambridge
University Press, eds. M. Povi\'c, P. Marziani, J. Masegosa, H. Netzer, S. H.
Negu, and S. B. Tessem
Clouds and aerosols in Puerto Rico ─ a new evaluation
The influence of aerosols, both natural and anthropogenic, remains a major area of uncertainty when predicting the properties and behaviour of clouds and their influence on climate. In an attempt to better understand warm cloud formation in a tropical marine environment, a period of intensive measurements took place in December 2004 in Puerto Rico, using some of the latest developments in online instrumentation such as aerosol mass spectrometers, cloud condensation nuclei counters and a hygroscopicity tandem differential mobility analyser. Simultaneous online measurements of aerosol size distributions, composition, hygroscopicity and optical properties were made near the lighthouse of Cape San Juan in the north-eastern corner of the island and at the top of East Peak mountain (1040 m a.s.l.), the two sites separated by 17 km. Additional measurements of the cloud droplet residual and interstitial aerosol properties were made at the mountain site, accompanied by measurements of cloud droplet size distributions, liquid water content and the chemical composition of cloud and rain water samples. <br><br> Both aerosol composition and cloud properties were found to be sensitive to wind sector. Air from the east-northeast (ENE) was mostly free of anthropogenic influences, the submicron fraction being mainly composed of non-sea salt sulphate, while that from the east-southeast (ESE) was found to be moderately influenced by populated islands upwind, adding smaller (<100 nm), externally mixed, carbonaceous particles to the aerosol that increased the number concentrations by over a factor of 3. This change in composition was also accompanied with a reduction in the measured hygroscopicity and fractional cloud activation potential of the aerosol. At the mountain site, the average cloud droplet concentrations increased from 193 to 519 cm<sup>−3</sup>, median volume diameter decreased from 20 to 14 μm and the liquid water content increased from 0.24 to 0.31 g m<sup>−3</sup> when the winds shifted from the ENE to ESE. Larger numbers of interstitial particles were recorded, most notably at sizes greater than 100 nm, which were absent during clean conditions. The average size of the residual particles and concentrations of cloudwater nitrate, sulphate and insoluble material increased during polluted conditions. <br><br> Previous studies in Puerto Rico had reported the presence of a significant non-anthropogenic organic fraction in the aerosols measured and concluded that this was a factor controlling the in situ cloud properties. However, this was not observed in our case. In contrast to the 1.00±0.14 μg m<sup>−3</sup> of organic carbon measured in 1992 and 1995, the organic matter measured in the current study of 0.17±0.35 μg m<sup>−3</sup> is many times lower, most of which can be attributed to anthropogenic sources. During clean conditions, the submicron aerosol was observed to be almost entirely inorganic, an observation supported by the hygroscopicity measurements. This suggests that organic aerosols from marine sources may not be completely ubiquitous (either spatially or temporally) in this environment and requires further investigation to quantify their true extent and implications, with more extensive, longer-term sampling in conjunction with wind field analyses
Steady state representation of the homogeneous cooling state of a granular gas
The properties of a dilute granular gas in the homogeneous cooling state are
mapped to those of a stationary state by means of a change in the time scale
that does not involve any internal property of the system. The new
representation is closely related with a general property of the granular
temperature in the long time limit. The physical and practical implications of
the mapping are discussed. In particular, simulation results obtained by the
direct simulation Monte Carlo method applied to the scaled dynamics are
reported. This includes ensemble averages and also the velocity autocorrelation
function, as well as the self-diffusion coefficient obtained from the latter by
means of the Green-Kubo representation. In all cases, the obtained results are
compared with theoretical predictions
Tissue remodelling and increased DNA damage in patients with incompetent valves in chronic venous insufficiency
Chronic venous insufficiency (CVI), in which blood return to the heart is impaired, is a prevalent condition worldwide. Valve incompetence is a complication of CVI that results in blood reflux, thereby aggravating venous hypertension. While CVI has a complex course and is known to produce alterations in the vein wall, the underlying pathological mechanisms remain unclear. This study examined the presence of DNA damage, pro-inflammatory cytokines and extracellular matrix remodelling in CVI-related valve incompetence. One hundred and ten patients with CVI were reviewed and divided into four groups according to age (<50 and ≥50 years) and a clinical diagnosis of venous reflux indicating venous system valve incompetence (R) (n = 81) or no reflux (NR) (n = 29). In vein specimens (greater saphenous vein) from each group, PARP, IL-17, COL-I, COL-III, MMP-2 and TIMP-2 expression levels were determined by RT-qPCR and immunohistochemistry. The younger patients with valve incompetence showed significantly higher PARP, IL-17, COL-I, COL-III, MMP-2 and reduced TIMP-2 expression levels and a higher COL-I/III ratio. Young CVI patients with venous reflux suffer chronic DNA damage, with consequences at both the local tissue and systemic levels, possibly associated with ageing.This study (FIS-PI18/00912) was supported by the Instituto de Salud Carlos III (Plan Estatal de I + D+i 2013-2016) and co-financed by the European Development Regional Fund “A way to achieve Europe” (ERDF) and B2017/BMD-3804 MITIC-CM
Electro-enzymatic ATP regeneration coupled to biocatalytic phosphorylation reactions
Funding Information: A.L.D, M.P. and M.V. thank grants RTI2018-095090-B-I00 and PID2021-1241160B-I00 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union, and 2021AEP014 funded by CSIC. G.G.M. thanks grant BES-2016-078815 funded by MCIN/AEI/ 10.13039/501100011033 and by the European Union. I.L.-M. and M.V. acknowledge financial support through grant S2018/BAA-4403 SINOXPHOS-CM (EU-FEDER). I.A.C.P. and A.M.C. thank support from the Fundação para a Ciência e Tecnologia through fellowship SFRH/BD/146475/2019 and MOSTMICRO-ITQB R&D Unit (UIDB/04612/2020, UIDP/04612/2020) and LS4FUTURE Associated Laboratory (LA/P/0087/2020). Publisher Copyright: © 2023 The Author(s)Adenosine-5-triphosphate (ATP) is the main energy vector in biological systems, thus its regeneration is an important issue for the application of many enzymes of interest in biocatalysis and synthetic biology. We have developed an electroenzymatic ATP regeneration system consisting in a gold electrode modified with a floating phospholipid bilayer that allows coupling the catalytic activity of two membrane-bound enzymes: NiFeSe hydrogenase from Desulfovibrio vulgaris and F1Fo-ATP synthase from Escherichia coli. Thus, H2 is used as a fuel for producing ATP. This electro-enzymatic assembly is studied as ATP regeneration system of phosphorylation reactions catalysed by kinases, such as hexokinase and NAD+-kinase for respectively producing glucose-6-phosphate and NADP+.publishersversionpublishe
Impact of the COVID-19 pandemic on the care of cancer patients in Spain
Background: Studies evaluating the effects of the COVID-19 pandemic on public healthcare systems are limited, particularly in cancer management. As no such studies have been carried out in Spain, our objective is to describe and quantify the impact of the COVID-19 pandemic on cancer patients in Spanish hospitals during the first wave of the pandemic. Materials and methods: This retrospective, multicenter, nationwide study collected information from hospital departments treating oncology patients. An electronic questionnaire comparing outcomes and management of oncohematological patients for the March-June 2019 and March-June 2020 periods was used. Results: Information from 78 departments (36 tertiary hospitals) was analyzed. Forty-four departments implemented adapted protocols during March 2020. Most of these (n = 38/44; 86.4%) carried out COVID-19 triage, while 26 of 44 (59.1%) carried out onsite polymerase chain reaction tests for clinically suspected cases. A shift from in-person to telephone visits was observed in 43 of 44 (97.7%) departments. Comparing the March-June 2019 and March-June 2020 periods, the number of new patients decreased by 20.8% (from 160.2 to 126.4). Decreases were also seen in the mean number of total (2858.2 versus 1686.1) and cancer (465.5 versus 367.2) biopsies, as well as the mean number of bone marrow biopsies (30.5 versus 18.6). Concerning the number of patients visiting specific cancer care departments, a decrease from 2019 to 2020 was seen for mean number of chemotherapy treatments (712.7 versus 643.8) and radiation therapy (2169.9 versus 2139.9). Finally, a reduction from 2019 to 2020 of 12.9% (from 8.6 to 7.4) in the mean number of patients included in clinical trials was noted. Conclusions: This study provides the first comprehensive data concerning the impact of COVID-19 on cancer care in Spain. The pandemic caused a 20.8% decrease in newly diagnosed patients, which may impact future outcomes. Measures must be taken to ensure cancer management receives priority in times of healthcare emergencies
First survey of Wolf-Rayet star populations over the full extension of nearby galaxies observed with CALIFA
The search of extragalactic regions with conspicuous presence of Wolf-Rayet
(WR) stars outside the Local Group is challenging task due to the difficulties
in detecting their faint spectral features. In this exploratory work, we
develop a methodology to perform an automated search of WR signatures through a
pixel-by-pixel analysis of integral field spectroscopy (IFS) data belonging to
the Calar Alto Legacy Integral Field Area survey, CALIFA. This technique
allowed us to build the first catalogue of Wolf-Rayet rich regions with
spatially-resolved information, allowing to study the properties of these
complexes in a 2D context. The detection technique is based on the
identification of the blue WR bump (around He II 4686 {\AA}, mainly associated
to nitrogen-rich WR stars, WN) and the red WR bump (around C IV 5808 {\AA} and
associated to carbon-rich WR stars, WC) using a pixel-by-pixel analysis. We
identified 44 WR-rich regions with blue bumps distributed in 25 galaxies of a
total of 558. The red WR bump was identified only in 5 of those regions. We
found that the majority of the galaxies hosting WR populations in our sample
are involved in some kind of interaction process. Half of the host galaxies
share some properties with gamma-ray burst (GRB) hosts where WR stars, as
potential candidates to being the progenitors of GRBs, are found. We also
compared the WR properties derived from the CALIFA data with stellar population
synthesis models, and confirm that simple star models are generally not able to
reproduce the observations. We conclude that other effects, such as the binary
star channel (which could extend the WR phase up to 10 Myr), fast rotation or
other physical processes that causes the loss of observed Lyman continuum
photons, are very likely affecting the derived WR properties, and hence should
be considered when modelling the evolution of massive stars.Comment: 33 pages, accepted for publication in A&
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