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Botanical filtration is a biological-based treatment method suitable for removing hazardous volatile organic compounds (VOCs) from air streams, based on forcing an air flow through a porous substrate and foliage of a living botanical compartment. The pathways and removal mechanisms during VOC bioremediation have been largely investigated; however, their mathematical representation is well established only for the non-botanical components of the system. In this study, we evaluated the applicability of such a modelling scheme to systems which include a botanical compartment. We implemented a one-dimensional numerical model and performed a global sensitivity analysis to measure the input parameters influence on the transient and steady biofilter responses. We found that the most sensitive parameters on the transient-state behaviour were the mass transfer coefficient between gas and solid surfaces, and the fraction of solid surfaces covered by the biofilm; the steady-state response was primarily influenced by the biofilm specific surface area and the fraction of surfaces covered by the biofilm. We calibrated the identified set of parameters and successfully validated the model against data from a pilot-scale installation. The results showed that the application of the model to systems with a botanical compartment is feasible, although under a strict set of assumptions.

The use of seawater in horticulture is underestimated. Although pure seawater is harm-ful to most living plants, diluted seawater could represent a promising integration to meet the crop’s nutrient and water requirements. In the current trial, we compared the effects of moderate and high concentrations of seawater and a comparable NaCl solution on a salt-tolerant (Tetragonia tetragonioides) and a salt-sensitive (Lactuca sativa) crop grown in hydroponics. We tested the hy-pothesis that, due to its mineral composition, diluted seawater would result in a less stressful growing medium than NaCl. We observed that diluted seawater resulted in a less detrimental growing medium compared to an EC-comparable NaCl solution, with remarkable differences between the salt-tolerant and the salt-sensitive species. While the growth rates in Tetragonia did not vary between the two types of stress, diluted seawater led to a higher FW and DW biomass yield in the salt-sensitive lettuce compared to the NaCl treatment. Moreover, NaCl reduced the water consumption and water productivity in Tetragonia. In lettuce, NaCl-treated plants demonstrated lower water use efficiency and water productivity compared to the EC-comparable seawater treatment. Physiological parameters and the concentration of mineral elements, phenolics and proline also demonstrated that, due to different mineral composition, seawater is a less stressful growing medium compared to a NaCl solution at comparable EC.

Phytotechnological approaches using living plants are currently being proposed to address a wide range of environmental purposes including the treatment of landfill leachate (LL). Despite their popularity, few studies have investigated this possibility under actual Mediterranean conditions using fast-growing trees. This research reports the results of a two-year project where poplar and willow grown in mesocosm were tested for their ability to withstand and remove specific pollutants from different [Low: 7% (1st year) and 15% (2nd year); High: 15% (1st year) and 30% (2nd year)] amounts of LL. Results indicate that both species were able to treat 340 (Low) and 680 (High) m3 ha−1 in the establishment year (70 days) and 2470 (Low) and 4950 (High) m3 ha−1 in the second year (150 days). Both species yielded the same aboveground biomass, but under high LL treatment, poplar performed better than willow. Poplar showed on average significantly higher extraction rates for Cd, Cu, P, and N than willow. Moreover, under high LL treatment, poplar also seemed more efficient than willow in decreasing the concentration of specific pollutants (BOD5, COD and As) in output effluent. However, with low LL loads both species were able to significantly reduce other compounds (i.e. NH4–N, Cu and Ni). By contrast, Cl, surfactants, and NO3–N, had a tendency to accumulate over time in the effluent and could still represent an actual constraint to large-scale application of the technique. The fate of such pollutants should be investigated with further research to better inform strategies used to manage low amounts of high-concentrated effluent.

Phytoremediation is a potentially suitable technique for the reclamation of toxic landfill leachate (LL) by decreasing its volume through water uptake and improving its composition by uptake, accumulation and amelioration of pollutants. We investigated the use of two parameters, the LL concentration and the Leachate Pollution Index (LPI), a method used to determine the phytotoxicity potential of a leachate source based on a weighted sum of its components, to set the best LL dilution to apply when poplar clone ‘Orion’ and willow clone ‘Levante’ are selected for phytoremediation. Cuttings were watered with five LL concentrations ranging from 0 to 100%. The poplar clone showed significantly higher values than the willow clone for lowest effective concentration index (LOEC) for leaf (i.e. 11.3% vs 10.5%; p = 0.0284) and total biomass (i.e. 10.9% vs 10.6%; p = 0.0402) and for lowest effective LPI for leaf (i.e. 12.3 vs 12.1; p = 0.0359) and total biomass (i.e. 12.8 versus 12.2; p = 0.0365), respectively, with effectiveness demonstrating the LOEC or LPI value at which the parameter is negatively affected. Photosynthetic rates were higher in poplar than willow in both control and the lowest LL dilution, but rapidly declined in both at higher LL dilutions. Although a direct translation of data from bench trials to field conditions should be investigated, we concluded that in the establishment phase, the poplar hybrid is more tolerant than the willow hybrid to LL. We also provide evidence for LPI as a potential predictor for setting LL irrigation levels in the initial phase of a phyto-treatment approach.

The lack of natural resources, especially good-quality cropland and renewable water resources is threatening food production potential in marginal agricultural ecosystems, which are already negatively affected by climate change. Since the world's major crops are proving inadequate to supply the calories and nutrients for people in these areas, new crops are sought that can withstand harsh ecological environmental conditions. In the current trial, we assessed the growth and productivity of Tetragonia tetragonioides (Pallas) Kuntz. in a floating hydroponic system supplied with different seawater proportions (i.e. 15% and 30% seawater, EC = 9.8 and 18.0 dS m−1). Moreover, the effects of different salinity levels on mineral elements accumulation, production of osmotic solutes and secondary metabolites were determined, along with the salt removal capacity of the crop. The results indicated that plant growth was not affected by either of the seawater treatments used in this study. The increased leaf succulence and the reduction of both leaf area and specific leaf area with increasing salinity might represent an essential feature of this salt-tolerant species associated to the plants need of limiting transpiration. Low seawater treated plants showed a significantly higher biomass yield per liter of (sea)water used (117%) than the control. Under these conditions plants accumulated the highest amount of Mg (+31% and 48% in medium and high seawater treated plants compared with the control) and Cu (+14% and 30%, respectively) along with increasing proline and decreasing nitrate concentrations. By contrast, we found that seawater supply resulted in a Na-enriched leaf biomass that may represent an issue for human health. We concluded that Tetragonia tetragonioides can be grown in saline agriculture up to a salinity level characterized by an EC of 18 dS m-1 but further investigation is required to address Na accumulation in leaves.

Plants are not only able to perceive and adaptively respond to external information but also forthcoming hazards and stresses. Recent evidence suggests the role of volatile compounds as signal molecules that mediate plant interactions. Here we tested the hypothesis that unstressed plants are able to respond to stress cues emitted from their salinity-stressed neighbors and initiate a priming effect for a future salinity stress. A two step experiment was designed: in the first step (Step1), a group of Vicia faba plants (Receivers) neighbored a group of plants stressed for two weeks with 150 mM NaCl (Emitters), exchanging only airborne signals. In the second step (Step2) the Receivers and a group of unprimed plants were further treated with 150 mM NaCl, and the salinity tolerance of the two groups was compared. In Step1, after 2 hours from the application of salinity stress in the Emitters, a significant decrease of stomatal conductance was observed in the Receivers, and photosynthetic rate decreased after 24 h. A significant reduction of dry weight in Receivers was reported. Surprisingly in Step2, primed plants were better prepared to cope with the salinity stress: stomatal conductance, photosynthetic rate and relative growth rate were significantly higher than unprimed plants. This demonstrates that V. faba plants are able to perceive stress cues emitted by stressed neighbors and respond by eliciting a priming effect that prepares them for a possible future stress. Furthermore, the volatile organic compounds emitted by the stressed plants were analyzed and a list of possible airborne cues involved in this mechanism is given.

To date, the chemical composition and the amount and diversity of volatile organic compounds (VOCs) released by different woody plants samples have been measured and characterized through one of the most common techniques, the gas chromatography–mass spectrometry. However, this technique is very time-consuming and requires sample preparation. By contrast, the Proton-Transfer-Reaction Time-of-Flight Mass spectrometry (PTR-ToF-MS) represents an innovative tool able to provide the whole mass spectra of VOCs with short response time, high mass resolution and without sample preparation. This technique is fast, non-invasive, highly sensitive with a rapid detection system and a very low mass fragmentation of the volatile molecules. The goal of this study was to characterize the VOCs profile of different wood sample cores using a PTR-ToF-MS tool and thereafter to assess whether VOC emissions were specific for some groups of trees. VOCs released from core wood samples belonging to 14 different species were analyzed and subsequently, using an advanced multivariate class-modeling approach, the groups (softwood and hardwood) and the different tree species were discriminated. PTR-ToF-MS was able to detect VOCs from wood and to discriminate between hardwood and softwood and among different species. The great potential and the rapidity of this analysis method allow the PTR-ToF-MS to become a commercial standard tool for monitoring VOCs emitted by wood.

Contains fulltext : 172109.pdf (publisher's version ) (Open Access), PURPOSE: Traditionally, total thyroidectomy has been advocated for patients with tumors larger than 1 cm. However, according to the ATA and NCCN guidelines (2015, USA), patients with tumors up to 4 cm are now eligible for lobectomy. A rationale for adhering to total thyroidectomy might be the presence of contralateral carcinomas. The purpose of this study was to describe the characteristics of contralateral carcinomas in patients with differentiated thyroid cancer (DTC) larger than 1 cm. METHODS: A retrospective study was performed including patients from 17 centers in 5 countries. Adults diagnosed with DTC stage T1b-T3 N0-1a M0 who all underwent a total thyroidectomy were included. The primary endpoint was the presence of a contralateral carcinoma. RESULTS: A total of 1313 patients were included, of whom 426 (32 %) had a contralateral carcinoma. The contralateral carcinomas consisted of 288 (67 %) papillary thyroid carcinomas (PTC), 124 (30 %) follicular variant of a papillary thyroid carcinoma (FvPTC), 5 (1 %) follicular thyroid carcinomas (FTC), and 3 (1 %) Hurthle cell carcinomas (HTC). Ipsilateral multifocality was strongly associated with the presence of contralateral carcinomas (OR 2.62). Of all contralateral carcinomas, 82 % were

While the importance of cell-type specificity in plant adaptive responses is widely accepted, only a limited number of studies have addressed this issue at the functional level. We have combined electrophysiological, imaging, and biochemical techniques to reveal physiological mechanisms conferring higher sensitivity of apical root cells to salinity in barley. We show that salinity application to the root apex arrests root growth in a highly tissue- and treatment-specific manner. Although salinity-induced transient net Na+ uptake was about 4-fold higher in the root apex compared with the mature zone, mature root cells accumulated more cytosolic and vacuolar Na+ suggesting that higher sensitivity of apical cells to salt is not related to either enhanced Na+ exclusion or sequestration inside the root. Rather, the above differential sensitivity between the two zones originates from a 10-fold difference in K+ efflux between the mature zone and the apical region (much poorer in the root apex) of the root. Major factors contributing to this poor K+ retention ability are: (1) an intrinsically lower H+-ATPase activity in the root apex; (2) greater salt-induced membrane depolarization and (3) a higher ROS production under NaCl and a larger density of ROS-activated cation currents in the apex. Salinity treatment increased (2 to 5 fold) the content of 10 (out of 25 detected) amino acids in the root apex but not in the mature zone and changed the organic acid and sugar contents. The causal link between observed changes in the root metabolic profile and regulation of transporters activity is discussed.

Purpose: Traditionally, total thyroidectomy has been advocated for patients with tumors larger than 1 cm. However, according to the ATA and NCCN guidelines (2015, USA), patients with tumors up to 4 cm are now eligible for lobectomy. A rationale for adhering to total thyroidectomy might be the presence of contralateral carcinomas. The purpose of this study was to describe the characteristics of contralateral carcinomas in patients with differentiated thyroid cancer (DTC) larger than 1 cm. Methods: A retrospective study was performed including patients from 17 centers in 5 countries. Adults diagnosed with DTC stage T1b-T3 N0-1a M0 who all underwent a total thyroidectomy were included. The primary endpoint was the presence of a contralateral carcinoma. Results: A total of 13

Alternative water sources for irrigation are needed to be found, as agriculture is currently using the 70% of total freshwater. Seawater use for growing crops has long been studied; while an agriculture based on pure seawater is currently impossible, seawater hydroponics may be viable, not aggravating salinization problems in soils. This work aimed at assessing the possibility of growing lettuce, chard and chicory with 3 seawater and freshwater blends (i.e. 5%–10%–15% of seawater). We investigated: i) crops growth, water consumptions, water use efficiency (WUE), water productivity (WP); ii) photosynthetic parameters; iii) principal mineral elements, soluble sugars and phenolics concentration. Lettuce productivity was negatively affected by 10% and 15% of seawater, whereas chard and chicory's growth were not affected by any blend. Interestingly, water consumptions dropped and WUE significantly upturned in every tested crop accordingly with increased seawater concentrations. Leaf concentration of Na+ and of some other ions increased. We concluded that certain amounts of seawater can be practically used in hydroponics, allowing freshwater saving and increasing certain mineral nutrients concentrations.

Tragopogon pratensis is a small herbaceous plant that uses wind as the dispersal vector for its seeds. The seeds are attached to parachutes that increase the aerodynamic drag force and increase the total distance travelled. Our hypothesis is that evolution has carefully tuned the air permeability of the seeds to operate in the most convenient fluid dynamic regime. To achieve final permeability, the primary and secondary fibres of the pappus have evolved with complex weaving; this maximises the drag force (i.e., the drag coefficient), and the pappus operates in an “optimal” state. We used computational fluid dynamics (CFD) simulations to compute the seed drag coefficient and compare it with data obtained from drop experiments. The permeability of the parachute was estimated from microscope images. Our simulations reveal three flow regimes in which the parachute can operate according to its permeability. These flow regimes impact the stability of the parachute and its drag coefficient. From the permeability measurements and drop experiments, we show how the seeds operate very close to the optimal case. The porosity of the textile appears to be an appropriate solution to achieve a lightweight structure that allows a low terminal velocity, a stable flight and a very efficient parachute for the velocity at which it operates., Control & Operations, Aerospace Engineering

Taxonomic identification is traditionally carried out with dichotomous keys, or at least computer-based identification keys, often on the basis of subjective visual assessment and frequently unable to detect small differences at subspecies and varietal ranks. The aims of the present work were to (1) clearly discriminate a wide group of accessions (species, subspecies and varieties) belonging to the genus Banksia on the basis of 14 phyllometric parameters determined by image analysis of the leaves, and (2) unequivocally identify the accessions with a relatively simple back-propagation neural-network (BPNN) architecture (single hidden layer) in order to develop a complementary method for fast botanical identification. The results indicate that this kind of network could be effectively and successfully used to discriminate among Banksia accessions, as the BPNN enabled a 93% unequivocal and correct simultaneous identification. Our BPNN had the advantage of being able to resolve subtle associations between characters, and of making incomplete data (i.e. absence of Banksia flower parameters such as the colour or size of styles) useful in species diagnostics. This method is relatively useful; it is easy to execute as no particular competences are necessary, equipment is low cost (scanner connected to a PC and software available as freeware) and data acquisition is fast and effective. © CSIRO 2009.