Phytoremediation using high production crops could be an alternative for the recovery of metals polluted soils. In this sense, the Arundo donax L. energy crop has shown tolerance to moderate ...concentrations of heavy metals. The objective of this work was to test the tolerance of micropropagated plants of Arundo donax to increasing concentrations of cadmium, chromium, cooper, nickel and lead, in an in vitro culture medium. Biomass production and concentration of heavy metal in shoots and roots were analyzed. Results showed that heavy metals were accumulated mostly in subterranean organs. The increase in heavy metal concentration was dose dependent and not always follows a linear relationship. Arundo donax showed a broad tolerance to cadmium (0.5 mM), chromium (0.2 mM), cooper (2 mM), nickel (0.5 mM) and lead (1 mM). In relation to cooper, Arundo donax showed a hyperaccumulative potential. These results suggest the potential use of Arundo donax in the phytomanagement of polluted soils although further studies should be carried out using polluted soils.
•In vitro assays show the tolerance of Arundo donax micropropagated plants to metals.•Arundo donax presents high tolerance to cadmium, chromium, cooper, nickel and lead.•The highest metal accumulation is observed in subterranean organs.•Arundo donax behaves as a Cu hyperaccumulator in the assay conditions.•Arundo donax could be used in the phytomanagement of metal polluted soils.
We propose a new scheme for supplying voltages to the electrodes of microfabricated ion traps, enabling access to a regime in which changes to the trapping potential are made on timescales much ...shorter than the period of the secular oscillation frequencies of the trapped ions. This opens up possibilities for speeding up the transport of ions in segmented ion traps and also provides access to control of multiple ions in a string faster than the Coulomb interaction between them. We perform a theoretical study of ion transport using these methods in a surface-electrode trap, characterizing the precision required for a number of important control parameters. We also consider the possibilities and limitations for generating motional state squeezing using these techniques, which could be used as a basis for the investigation of Gaussian-state entanglement.
The influence of the surface characteristics of colloidal drug carriers in their interaction with different biological surfaces is becoming increasingly evident. In order to investigate the ...importance of these characteristics in their interaction with the ocular mucosa, we developed three types of nanocapsules that differ in their surface properties: poly-ε-caprolactone (PECL) nanocapsules, chitosan (CS)-coated PECL nanocapsules and poly(ethylene glycol) (PEG)-coated PECL nanocapsules. Two different approaches were used to form these polymer coated nanocapsules: (i) the electrostatic anchorage of the coating onto the PECL nanocapsules—in the case of CS—and (ii) the use of the previously synthesized copolymer PECL-PEG for the formation of the nanocapsules. In both cases, the systems, prepared by the interfacial deposition technique, were loaded with a fluorescent dye (rhodamine) in order to quantify and visualize their interaction with the ocular surface ex vivo and in vivo. An important conclusion from the ex vivo studies is that the developed systems, and specially the CS-coated ones, enhanced the penetration of the encapsulated dye through the cornea. This effect was not simple due to the physical presence of the nanocapsules but to their ability to carry the encapsulated compound. The second conclusion from the confocal laser scanning microscopy (CLSM) studies is that the systems were able to enter the corneal epithelium by a transcellular pathway and that the penetration rate was dependent on the coating composition. The images suggest that the PEG coating accelerates the transport of the nanocapsules across the whole epithelium, whereas the CS coating favours the retention of the nanocapsules in the superficial layers of the epithelium. The specific behaviour of CS-coated systems was also corroborated in vivo. These results indicate that the surface composition of colloidal drug carriers affects their biodistribution in the eye. Therefore, this surface modification approach can be used as a targeting strategy in ocular drug delivery.
When xylan-containing lignocellulosic materials are subjected to the action of heat in an aqueous medium (autohydrolysis reaction) under suitable operational conditions, the heterocyclic ether bonds ...of the polymeric chain are split to give xylooligosaccharides (XO) and a variety of other products derived from hemicelluloses, lignin and extractives. For product applications requiring high-purity XO, subsequent purification stages have to be implemented. Various strategies have been evaluated for refining
Eucalyptus wood autohydrolysis liquors, including the two-stage reaction, precipitation and solvent extraction of freeze-dried, dewaxed liquors. Data on the degree of xylooligosaccharide recovery as well as on the composition of the isolates (measured in terms of hemicellulose-derived products and non-saccharide products) are provided for the various operational procedures assayed.
The increasingly widespread use of CSP (concentrated solar power) plants to produce electricity has generated a constant search to improve and optimize final production. These plants are looking for ...new technologies and methodologies that offer significant, reliable strategies which can be applied to their systems. Clouds are hydrometeors which affect solar radiation, decreasing its value and, consequently, electricity production. Knowing when solar radiation is obstructed by clouds provides useful information to CSP operators to adapt electricity production to the cloud presence, optimizing electricity production processes. As a result of this necessity to study cloud cover, short and medium-term cloudiness forecasting is presented here, where cloudiness is predicted for the following three hours.
•A methodology has been developed for estimating clouds in total sky imagery (TSI-880).•Remote sensing techniques were used to estimate cloud coverage in satellite imagery.•Cloudiness forecasting has been made in the short- and medium-term (1–180 min).•Results were shown for cloudless, partially-cloudy and overcast skies for 2010–2011.•In general, TSI forecasting presents better results than MSG for the first 40 min.
Abstract
Legumes house nitrogen-fixing endosymbiotic rhizobia in specialized polyploid cells within root nodules, which undergo tightly regulated metabolic activity. By carrying out expression ...analysis of transcripts over time in Medicago truncatula nodules, we found that the circadian clock enables coordinated control of metabolic and regulatory processes linked to nitrogen fixation. This involves the circadian clock-associated transcription factor LATE ELONGATED HYPOCOTYL (LHY), with lhy mutants being affected in nodulation. Rhythmic transcripts in root nodules include a subset of nodule-specific cysteine-rich peptides (NCRs) that have the LHY-bound conserved evening element in their promoters. Until now, studies have suggested that NCRs act to regulate bacteroid differentiation and keep the rhizobial population in check. However, these conclusions came from the study of a few members of this very large gene family that has complex diversified spatio-temporal expression. We suggest that rhythmic expression of NCRs may be important for temporal coordination of bacterial activity with the rhythms of the plant host, in order to ensure optimal symbiosis.
A nodule circadian clock involving the gene Late Elongated Hypocotyland rhythmic expression of nodule-specific cysteine-rich peptides coordinates waves of metabolic and regulatory activity during symbiosis.
Clinical isolates of Neisseria meningitidis from cases of meningococcal disease, collected between January 2000 and December 2004, were identified and typed at the French National Reference Centre. A ...representative subset of 546 isolates from among 2882 isolates was further genotyped by multilocus sequence typing to determine their genetic lineages (clonal complexes) and the degree of diversification among different clonal complexes. Representative isolates of the main clonal complexes were tested for their virulence in mice and for proapoptotic effects on human epithelial cells. High genetic diversity in some genetic lineages (ST-32 and ST-41/44) was correlated with heterogeneity in virulence in mice and proapoptotic effects on human epithelial cells. In contrast, the homogeneous genetic structure of isolates of the ST-11 clonal complex, regardless of their serogroup, correlated positively with a fatal outcome of the infection, increased virulence in mice and increased proapoptotic effects on human epithelial cells.
Previous studies have shown the existence of an acute phase response in dogs with heartworm (Dirofilaria immitis), probably caused by the vascular inflammation that occurs during the pathogenesis of ...this disease. In addition, it has been seen that this acute phase response persists after finishing treatment, especially in dogs with pulmonary hypertension (PH). Furthermore, echocardiographic studies have shown that PH and endarteritis appear to persist for at least 10 months after completion of adulticide treatment, suggesting that the vascular changes in these dogs may not be reversible. Therefore, the objective of this study was to evaluate the serum concentrations of different positive acute phase proteins (APP) C reactive-protein (CRP), haptoglobin and ferritin and negative APP (albumin and paraoxonase-1 (PON-1)), and the usefulness of the endothelin-1 (ET-1) and adiponectin, in dogs infected by D. immitis to evaluate their usefulness as diagnostic biomarkers of vascular damage and PH and their progression throughout therapy up to 7 months after the end of adulticide treatment. Twenty-five heartworm-infected dogs received adulticide treatment, and serum measurements were performed on the day of diagnosis (day 0), day of discharge (day 90), and 6 months after discharge (day 270). In addition, presence or absence of PH was also echocardiographically determined using the Right Pulmonary Artery Distensibility Index. PH was present in 44% of the dogs on day 0 and day 90, and in 48% of dogs on day 270. Alterations were observed in the concentrations of all APP throughout the study, persisting the alterations in PON-1 and ferritin on day 270. Depending on the presence or absence of PH, CRP showed significant differences throughout the study, as did ET-1. On the other hand, adiponectin did not show variations throughout the study, so it did not seem a useful marker in this disease. These results could reflect the possible persistence of vascular inflammation up to 7 months after finishing treatment, whether or not there was PH, and consolidate the study of APP as useful markers in heartworm disease. Moreover, persistent PH could be the consequent clinical manifestation in dogs with more severe vascular alterations so the study of APP, especially CRP, and ET-1 could be especially advantageous in these patients in the early evaluation of the disease, as well as for the determination of disease severity, monitoring therapeutic responses, and predicting outcomes.
•An acute phase response persists in dogs with heartworm 7 months after treatment.•C reactive-protein was higher in dogs with pulmonary hypertension after treatment.•Endothelin-1 is a good biomarker for pulmonary hypertension, before and after treatment.•The results could reflect a persistence of vascular inflammation 7 months after treatment.
► A MARS model is used as a predictive model of cyanotoxins presence. ► Cyanobacterial HABs are dangerous for people and the environment in fresh waters. ► The influence of the different variables in ...this process is studied in detail.
There is an increasing need to describe cyanobacteria blooms since some cyanobacteria produce toxins, termed cyanotoxins. These latter can be toxic and dangerous to humans as well as other animals and life in general. It must be remarked that the cyanobacteria are reproduced explosively under certain conditions. This results in algae blooms, which can become harmful to other species if the cyanobacteria involved produce cyanotoxins. In this research work, the evolution of cyanotoxins in Trasona reservoir (Principality of Asturias, Northern Spain) was studied with success using the data mining methodology based on multivariate adaptive regression splines (MARS) technique. The results of the present study are two-fold. On one hand, the importance of the different kind of cyanobacteria over the presence of cyanotoxins in the reservoir is presented through the MARS model and on the other hand a predictive model able to forecast the possible presence of cyanotoxins in a short term was obtained. The agreement of the MARS model with experimental data confirmed the good performance of the same one. Finally, conclusions of this innovative research are exposed.
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