92 research outputs found

    Hydrology-oriented (adaptive) silviculture in a semiarid pine plantation: How much can be modified the water cycle through forest management?

    Full text link
    [EN] Hydrology-oriented silviculture might adapt Mediterranean forests to climatic changes, although its implementation demands a better understanding and quantification on the water fluxes. The influence of thinning intensity (high, medium, low and a control) and its effect on the mid-term (thinned plots in 1998 and 2008) on the water cycle (transpiration, soil water and interception) and growth [basal area increment (BAI)] were investigated in 55-year-old Aleppo pine trees. Thinning enhanced a lower dependence of growth on climate fluctuations. The high-intensity treatment showed significant increases in the mean annual BAI (from 4.1 to 17.3 cm(2)) that was maintained in the mid-term. Thinning intensity progressively increased the sap flow velocity (v (s)) in all cases with respect to the control. In the mid-term, an increased functionality of the inner sapwood was also observed. Mean daily tree water use ranged from 5 (control) to 18 (high intensity) l tree(-1). However, when expressed on an area basis, daily transpiration ranged from 0.18 (medium) to 0.30 mm (control), meaning that in spite of the higher transpiration rates in the remaining trees, stand transpiration was reduced with thinning. Deep infiltration of water was also enhanced with thinning (about 30 % of rainfall) and did not compete with transpiration, as both presented opposite seasonal patterns. The changes in the stand water relationships after 10 years were well explained by the forest cover metric. The blue to green water ratio changed from 0.15 in the control to 0.72 in the high-intensity treatment, with the remaining treatments in the 0.34-0.48 range.This study is a component of two research projects: ‘‘CGL2011-28776-C02-02, Hydrological characterisation of forest structures at plot scale for an adaptive management, HYDROSIL’’, funded by the Spanish Ministry of Science and Innovation and FEDER funds, and ‘‘Determination of hydrological and forest recovery factors in Mediterranean forests and their social perception’’, led by Dr. E. Rojas and supported by the Ministry of Environment, Rural and Marine Affairs. The authors are grateful to the Valencia Regional Government (CMAAUV, Generalitat Valenciana) and the VAERSA staff for their support in allowing the use of the La Hunde experimental forest and for their assistance in carrying out the fieldwork. The second author thanks the Mundus 17 Program, coordinated by the University of Porto—Portugal.Campo García, ADD.; Gualberto Fernandes, TJ.; Molina Herrera, A. (2014). Hydrology-oriented (adaptive) silviculture in a semiarid pine plantation: How much can be modified the water cycle through forest management?. European Journal of Forest Research. 133(55):879-894. https://doi.org/10.1007//s10342-014-0805-7S8798941335

    Simultaneous assessment, through sap flow and stable isotopes, of water use efficiency (WUE) in thinned pines shows improvement in growth, tree-climate sensitivity and WUE, but not in WUEi

    Full text link
    [EN] In water-limited regions, adaptive management of forest and water relationships has been put forward, to implement hydrology-oriented silviculture to reduce stand evapotranspiration and, at the tree level, to improve growth and water use efficiency (WUE). The main goal of this study was to evaluate the effect of thinning in the short and medium term on tree growth, climate (drought) sensitivity, WUE performed using growth and sap flow measurements and WUEi performed using delta C-13 and delta O-18 isotopes, in a typical semiarid forest. This approach also evaluated the reliability of isotopes as indicators of the effects of adaptive forest management. A stagnated Aleppo pine plantation was experimentally thinned at high intensity (H98) in 1998 and at High (H), Medium (M) and Low (L) intensities in 2008, along with a control (C). Substantial limitation of tree growth was observed in C. Thinning not only increased growth, but also changed the.tree growth-precipitation relationships, with C trees depending more on precipitation than thinned trees did. WUEi after thinning was significantly affected only in the medium term, with C trees being more efficient (94.4 mu molCO(2)/molH(2)O) than H98 trees (88.7), especially in dry spells (100.7). WUEi was found to increase when precipitation decreased, regardless of the treatment. However, WUE increased sharply from C (1.26 g biomass/L H2O) to H (3.20 WO, showing a clear difference with WUEi observed in the same years. Thinning caused an increase in 8180 in the short term, but no relationship was found between 8180 and tree water use. It can be concluded that forest management improved WUE in spite of higher tree transpiration, but WUEi remained unchanged, probably due to an underestimate of photosynthetic capacity. The dual isotope (delta C-13 and delta O-18) conceptual model was not consistent with our experimental data. Thus, the question of whether stable isotopes can be used as a tool for addressing the ecophysiological impacts of thinning remains open. (C) 2015 Elsevier B.V. All rights reserved.This study is part of the research projects "CGL2011-28776-C02-02, HYDROSIL", "CGL2014-58127-C3-2, SILWAMED," funded by the Spanish Ministry of Science and Innovation and FEDER funds, and "Determination of hydrologic and forest recovery factors in Mediterranean forests and their social perception," supported by the Ministry of Environment, Rural and Marine Affairs. The authors are grateful to the Valencia Regional Government (CMAAUV, Generalitat Valenciana) and the VAERSA staff for their support in allowing the use of the La Hunde experimental forest and for their assistance in carrying out the fieldwork. We express our gratitude to Professor R. Montes for constructive criticism and suggestions on an earlier version of the paper. The first author thanks the Mundus 17 Programme, coordinated by the University of Porto (Portugal).The authors are grateful to the Valencia Regional Government (CMAAUV, Generalitat Valenciana) and the VAERSA staff for their support in allowing the use of the La Hunde experimental forest and for their assistance in carrying out the fieldwork. We express our gratitude to Professor R. Montes for constructive criticism and suggestions on an earlier version of the paper. The first author thanks the Mundus 17 Programme, coordinated by the University of Porto (Portugal).Gualberto-Fernandes, TJ.; Campo García, ADD.; Herrera Fernandez, R.; Molina Herrera, A. (2016). Simultaneous assessment, through sap flow and stable isotopes, of water use efficiency (WUE) in thinned pines shows improvement in growth, tree-climate sensitivity and WUE, but not in WUEi. Forest Ecology and Management. 361:298-308. doi:10.1016/j.foreco.2015.11.029S29830836

    Low temperature Terahertz Spectroscopy of LaFeO3_3, PrFeO3_3, ErFeO3_3, and LuFeO3_3: Quasimagnon resonances and ground multiplet transitions

    Full text link
    We report on zone center THz excitations of non-Jahn Teller LaFeO3_3, PrFeO3_3, ErFeO3_3, and LuFeO3_3 distorted perovskites under external magnetic fields up 7 T. Low temperature-low energy absorptions of LaFeO3_3 show antiferromagnetic and ferromagnetic quasimagnons at ω\omegaAFM ~31.4 and ω\omegaFM ~26.7 cm1^{-1} in the Γ\Gamma4 (Gx, Ay, Fz) representation. LuFeO3_3 is characterized by zero field magnetic resonances at ω\omegaAFM ~26.3 cm1^{-1} and ω\omegaFM ~22.4 cm1^{-1} in addition to Fe3+^{3+} Zeeman-split crystal field (CF) 6A1_1 ground transitions at ~10.4 cm1^{-1} triggered by structural deviations induced by smaller Lu 4f14^{14}. This local non-centrosymmetric departure is also found in ErFeO3_3 (Kramers 4f11^{11} Er3+^{3+} (4I15/2); {\Gamma}2 (Fx, Cy, Gz) <TSR ~93 K), but with the ~4 cm1^{-1} Fe3+^{3+} Zeeman branching strongly biased toward higher energies. Quasimagnons at ω\omegaAFM ~31.5 cm1^{-1} and ω\omegaFM ~21.5 cm1^{-1} in ErFeO3_3 do not undergo field induced band splits but a 13-fold increase in the antiferro (ω\omegaAMF) /ferro(ω\omegaAFM) intensity ratio. There is a remarkable field-dependent CF matching population balance between Fe3+^{3+} higher and Er3+^{3+} lower Zeeman branches. Antiferro- and ferro- resonances in PrFeO3_3 turn much broader as non-Kramers Pr3^3 introduces ligand changes at the A site leading into near degeneracy the antiferromagnetic mode and the lowest Pr3+^{3+} CF transition. We conclude that low energy excitations in RFeO3_3 (R=rare earth) strongly depend on the lanthanide ionic size. Minute lattice displacements also underlie considering non-centrosymmetric the most distorted RFeO3_3 (R=rare earth). Changes triggered by the smaller rare earth and the nonlinear intrinsic oxygen ion polarizability provide grounds for interplay of ionic and electronic interactions yielding ferroelectric spontaneous polarization.Comment: Full Manuscript and Supplemental Material, 73 pages, 27 figure

    Hydrogeochemical characteristics of a volcanic-sedimentary aquifer with special emphasis on Fe and Mn content: A case study in Mexico

    Get PDF
    Previous studies performed on the volcanic-sedimentary aquifer of the Tenancingo Valley (Mexico) reports high concentrations of Fe, Mn, and NO3 −, and water from several wells receives purification treatments due to presence of Fe and Mn. These studies have not achieved conclusive results regarding the origin of Fe and Mn, nor have hydrogeochemical evaluations of the aquifer been performed. The present study aimed to evaluate the physicochemical characteristics of the water and identify the geochemical processes that determine presence of Fe and Mn in groundwater. This characterization was based on physicochemical data from well and spring samples (16 samples) during dry and rainy seasons (June and November 2012, respectively). The EC, temperature and pH ranged from 125 to 793 μS cm−1 , 14.5 to 24.9 °C and 6.5 to 8.5 pH units, respectively. The Eh values ranged from −219 to 327 mV, indicating the existence of both reducing and oxidizing zones. Presence of Fe and Mn was detected in both springs and wells; concentrations were higher in well, exceeding 4 mg Fe L−1 and 0.5 mg Mn L−1 . Content of Si ranged from 12 to 47 mg L−1 . A model of the hydrogeochemical behavior of the aquifer was created to highlight the following: i) processes involved in water-rock interactions, including fluctuations in silicate levels that determine anionic and cationic content of water, and ii) redox reactions as the major control processes of Fe and Mn. Water quality for human use is restricted by Fe and Mn content and pH. For irrigation use, significant limitations were not presente

    A three-dimensional printed customized bolus: adapting to the shape of the outer ear

    Get PDF
    Background: The skin-sparing effect of megavoltage-photon beams in radiotherapy (RT) reduces the target coverage of superficial tumours. Consequently, a bolus is widely used to enhance the target coverage for superficial targets. This study evaluates a three-dimensional (3D)-printed customized bolus for a very irregular surface, the outer ear. Materials and methods: We fabricated a bolus using a computed tomography (CT) scanner and evaluated its efficacy. The head of an Alderson Rando phantom was scanned with a CT scanner. Two 3D boluses of 5- and 10-mm thickness were designed to fit on the surface of the ear. They were printed by the Stratasys Objet260 Connex3 using the malleable “rubber-like” photopolymer Agilus. CT simulations of the Rando phantom with and without the 3D and commercial high density boluses were performed to evaluate the dosimetric properties of the 3D bolus. The prescription dose to the outer ear was 50 Gy at 2 Gy/fraction. Results: We observed that the target coverage was slightly better with the 3D bolus of 10 mm compared with the commercial one (D98% 98.2% vs. 97.6%).The maximum dose was reduced by 6.6% with the 3D bolus and the minimum dose increased by 5.2% when comparing with the commercial bolus. In addition, the homogeneity index was better for the 3D bolus (0.041 vs. 0.073). Conclusion: We successfully fabricated a customized 3D bolus for a very irregular surface. The target coverage and dosimetric parameters were at least comparable with a commercial bolus. Thus, the use of malleable materials can be considered for the fabrication of customized boluses in cases with complex anatomy

    High-resolution hepatitis C virus subtyping using NS5B deep sequencing and phylogeny, an alternative to current methods

    Full text link
    HepatitisCvirus(HCV)is classified into seven major genotypesand67 subtypes. Recent studies haveshownthat inHCVgenotype 1-infected patients, response rates to regimens containingdirect-acting antivirals(DAAs)are subtype dependent. Currently available genotypingmethods have limited subtyping accuracy.Wehave evaluated theperformanceof adeep-sequencing-basedHCVsubtyping assay, developed for the 454/GS-Junior platform, in comparisonwith thoseof two commercial assays (VersantHCVgenotype 2.0andAbbott Real-timeHCVGenotype II)andusingdirectNS5Bsequencing as a gold standard (direct sequencing), in 114 clinical specimenspreviously tested by first-generation hybridization assay (82 genotype 1and32 with uninterpretable results). Phylogenetic analysis of deep-sequencing reads matched subtype 1 callingbypopulation Sanger sequencing(69%1b,31%1a) in 81 specimensandidentified amixed-subtype infection (1b/3a/1a) in one sample. Similarly,amongthe 32previously indeterminate specimens, identical genotypeandsubtype results were obtained by directanddeep sequencing in all but four samples with dual infection. In contrast, both VersantHCVGenotype 2.0andAbbott Real-timeHCVGenotype II failed subtype 1 calling in 13 (16%) samples eachandwere unable to identify theHCVgenotype and/or subtype inmore than half of the nongenotype 1 samples.Weconcluded that deep sequencing ismore efficient forHCVsubtyping than currently available methodsandallows qualitative identificationofmixed infectionsandmay bemorehelpfulwith respect to informing treatment strategies withnewDAA-containing regimens across allHCVsubtypesThis study has been supported by CDTI (Centro para el Desarrollo Tecnológico Industrial), Spanish Ministry of Economics and Competitiveness (MINECO), IDI-20110115; MINECO projects SAF 2009-10403; and also by the Spanish Ministry of Health, Instituto de Salud Carlos III (FIS) projects PI10/01505, PI12/01893, and PI13/00456. CIBERehd is funded by the Instituto de Salud Carlos III, Madrid, Spain. Work at CBMSO was supported by grant MINECO-BFU2011-23604, FIPSE, and Fundación Ramón Areces. X. Forns received unrestricted grant support from Roche and has acted as advisor for MSD, Gilead, and Abbvie. M. Alvarez-Tejado, J. Gregori, and J. M. Muñoz work in Roche Diagnostic

    Use of an interactomics pipeline to assess the potential of new antivirals against SARS-CoV-2

    Get PDF
    (Póster 80) Background: In late 2019 SARS-CoV-2 infection appeared in China, becoming a pandemic in 2020. The scientific community reacted rapidly, characterizing the viral genome and its encoded proteins, aiming at interfering with viral spreading with vaccines and antivirals. The receptor binding domain (RBD) of the viral spike (S) protein plays a key role in cell entry of the virus. It interacts with the cellular receptor for SARS-CoV-2, the membrane-bound human Angiotensin Converting Ectoenzyme 2 (ACE2). With the goal of monitoring interference with this interaction by potential antiviral drugs, we have set up at the Institute for Biomedicine of Valencia (IBV-CSIC) an interactomics pipeline targeting the initial step of viral entry. Methods: For the production part of the pipeline (pure RBD/Spike variants and soluble ACE2), see parallel poster. These proteins allowed monitoring of the RBD/Spike-ACE2 interaction in presence or absence of potential inhibitors. Thermal shift assays (thermofluor) were used for initial detection of compound binding at different ligand/protein ratios and media conditions (pH, buffers, chaotropic agents). Next, binding affinity and on/off kinetics were characterized using Biolayer interferometry (BLI), Surface plasmon resonance (SPR), Microscale Thermophoresis (MST) and/or Isothermal titration calorimetry (ITC). For protein-protein interactions, we mostly used BLI or SPR, whereas for proteinsmall compound analysis MST was generally best. Protein aggregation-dissociation was monitored by size exclusion chromatography with multiangle light scattering (SEC-MALS). Results: Candidates proven by thermal shift assays to bind to RBD/spike protein without affecting the integrity of these proteins were subjected to quantitative affinity measurements. We successfully demonstrated that BLI, SPR and MST can be used to follow the interactions between SARS-CoV- 2 proteins and the putative drug candidates, as well as to monitor the interference with Spike-Ace2 binding of potential drug candidates. While BLI and SPR displayed reproducible results in the measurement of protein-protein interaction (applied to soluble ACE2 used as a decoy), they were less suitable for measuring the binding of small molecules. The fact that most small compounds were only soluble in organic solvents made difficult to obtain a low signal/noise while using BLI, necessary for the assessment of the binding. We overcame that problem by using MST. After dilution of the compounds to the final experimental concentrations, the technique could detect a significant binding signal enough to calculate binding parameters. MST also allowed to measure the degree of interference that each compound was having on RBD/Spike-ACE2 interaction. The pipeline has been customized and validated with compounds of very different nature provided by different groups belonging to the PTI and other external laboratories, as well as with different Ace2 decoys designed at the IBV. Conclusions: The interactomics platform at the IBV has been used to successfully develop two different antiviral approaches in order to fight COVID-19. It has allowed technical specialization of the staff as well as the development, in a very short period of time, of two ambitious projects. We have demonstrated that we can perform interactomic characterization for challenging projects as well as provide information about binding of antivirals to potential new SARS-CoV-2 variants of concern

    Continuous cultivation of photosynthetic microorganisms: approaches, applications and future trends

    Get PDF
    The possibility of using photosynthetic microorganisms, such as cyanobacteria and microalgae, for converting light and carbon dioxide into valuable biochemical products has raised the need for new cost-efficient processes ensuring a constant product quality. Food, feed, biofuels, cosmetics and pharmaceutics are among the sectors that can profit from the application of photosynthetic microorganisms. Biomass growth in a photobioreactor is a complex process influenced by multiple parameters, such as photosynthetic light capture and attenuation, nutrient uptake, photobioreactor hydrodynamics and gas-liquid mass transfer. In order to optimize productivity while keeping a standard product quality, a permanent control of the main cultivation parameters is necessary, where the continuous cultivation has shown to be the best option. However it is of utmost importance to recognize the singularity of continuous cultivation of cyanobacteria and microalgae due to their dependence on light availability and intensity. In this sense, this review provides comprehensive information on recent breakthroughs and possible future trends regarding technological and process improvements in continuous cultivation systems of microalgae and cyanobacteria, that will directly affect cost-effectiveness and product quality standardization. An overview of the various applications, techniques and equipment (with special emphasis on photobioreactors) in continuous cultivation of microalgae and cyanobacteria are presented. Additionally, mathematical modelling, feasibility, economics as well as the applicability of continuous cultivation into large-scale operation, are discussed.This research work was supported by the grant SFRH/BPD/98694/2013 (Bruno Fernandes) from Fundacao para a Ciencia e a Tecnologia (Portugal). The authors thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013. The authors also thank the Project "BioInd Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" Co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDE
    corecore