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1.
Environ Pollut ; 231(Pt 1): 237-251, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28802993

ABSTRACT

Gentle remediation options (GRO) are based on the combined use of plants, associated microorganisms and soil amendments, which can potentially restore soil functions and quality. We studied the effects of three GRO (aided-phytostabilisation, in situ stabilisation and phytoexclusion, and aided-phytoextraction) on the soil microbial biomass and respiration, the activities of hydrolase enzymes involved in the biogeochemical cycles of C, N, P, and S, and bacterial community structure of trace element contaminated soils (TECS) from six field trials across Europe. Community structure was studied using denaturing gradient gel electrophoresis (DGGE) fingerprinting of Bacteria, α- and ß-Proteobacteria, Actinobacteria and Streptomycetaceae, and sequencing of DGGE bands characteristic of specific treatments. The number of copies of genes involved in ammonia oxidation and denitrification were determined by qPCR. Phytomanagement increased soil microbial biomass at three sites and respiration at the Biogeco site (France). Enzyme activities were consistently higher in treated soils compared to untreated soils at the Biogeco site. At this site, microbial biomass increased from 696 to 2352 mg ATP kg-1 soil, respiration increased from 7.4 to 40.1 mg C-CO2 kg-1 soil d-1, and enzyme activities were 2-11-fold higher in treated soils compared to untreated soil. Phytomanagement induced shifts in the bacterial community structure at both, the total community and functional group levels, and generally increased the number of copies of genes involved in the N cycle (nirK, nirS, nosZ, and amoA). The influence of the main soil physico-chemical properties and trace element availability were assessed and eventual site-specific effects elucidated. Overall, our results demonstrate that phytomanagement of TECS influences soil biological activity in the long term.


Subject(s)
Biodegradation, Environmental , Soil Microbiology , Soil Pollutants/analysis , Trace Elements/analysis , Bacteria/drug effects , Betaproteobacteria , Biomass , Denaturing Gradient Gel Electrophoresis , Europe , France , Plants , Soil/chemistry , Soil Pollutants/toxicity , Trace Elements/toxicity
2.
J Environ Manage ; 186(Pt 2): 301-313, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27817970

ABSTRACT

(Aided) phytostabilisation has been proposed as a suitable technique to decrease the environmental risks associated with metal(loid)-enriched mine tailings. Field scale evaluations are needed for demonstrating their effectiveness in the medium- to long-term. A field trial was implemented in spring 2011 in Cu-rich mine tailings in the NW of Spain. The tailings were amended with composted municipal solid wastes and planted with Salix spp., Populus nigra L. or Agrostis capillaris L. cv. Highland. Plant growth, nutritive status and metal accumulation, and soil physico- and bio-chemical properties, were monitored over three years (four years for plant growth). The total bacterial community, α- and ß-Proteobacteria, Actinobacteria and Streptomycetaceae were studied by DGGE of 16s rDNA fragments. Compost amendment improved soil properties such as pH, CEC and fertility, and decreased soil Cu availability, leading to the establishment of a healthy vegetation cover. Both compost-amendment and plant root activity stimulated soil enzyme activities and induced important shifts in the bacterial community structure over time. The woody plant, S. viminalis, and the grassy species, A. capillaris, showed the best results in terms of plant growth and biomass production. The beneficial effects of the phytostabilisation process were maintained at least three years after treatment.


Subject(s)
Biodegradation, Environmental , Copper/toxicity , Soil Microbiology , Soil Pollutants/toxicity , Soil/chemistry , Agrostis/growth & development , Bacteria/genetics , Biomass , Copper/pharmacokinetics , Microbial Consortia/genetics , Mining , Plant Roots/chemistry , Plant Roots/microbiology , Populus/growth & development , Salix/growth & development , Soil Pollutants/analysis , Soil Pollutants/pharmacokinetics , Solid Waste , Spain , Species Specificity
4.
Sci Total Environ ; 548-549: 370-379, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-26803735

ABSTRACT

Ni phytomining is a promising technology for Ni recovery from low-grade ores such as ultramafic soils. Metal-hyperaccumulators are good candidates for phytomining due to their extraordinary capacity for Ni accumulation. However, many of these plants produce a low biomass, which makes the use of agronomic techniques for improving their growth necessary. In this study, the Ni hyperaccumulators Alyssum serpyllifolium ssp. lusitanicum, A. serpyllifolium ssp. malacitanum, Alyssum bertolonii and Noccaea goesingense were evaluated for their Ni phytoextraction efficiency from a Ni-rich serpentine soil. Effects of soil inorganic fertilisation (100:100:125kgNPKha(-1)) and soil organic amendment addition (2.5, 5 or 10% compost) on plant growth and Ni accumulation were determined. All soil treatments greatly improved plant growth, but the highest biomass production was generally found after addition of 2.5 or 5% compost (w/w). The most pronounced beneficial effects were observed for N. goesingense. Total Ni phytoextracted from soils was significantly improved using both soil treatments (inorganic and organic), despite the decrease observed in soil Ni availability and shoot Ni concentrations in compost-amended soils. The most promising results were found using intermediate amount of compost, indicating that these types of organic wastes can be incorporated into phytomining systems.


Subject(s)
Biodegradation, Environmental , Brassicaceae/metabolism , Metals/analysis , Nickel/analysis , Soil Pollutants/analysis , Biomass , Brassicaceae/chemistry , Soil/chemistry
5.
Int J Phytoremediation ; 18(4): 406-15, 2016.
Article in English | MEDLINE | ID: mdl-26552496

ABSTRACT

In this study different bacterial inoculation methods were tested for tobacco plants growing in a mine-soil contaminated with Pb, Zn, and Cd. The inoculation methods evaluated were: seed inoculation, soil inoculation, dual soil inoculation event, and seed+soil inoculation. Each inoculum was added at two bacterial densities (10(6) CFUs mL(-1) and 10(8) CFUs mL(-1)). The objectives were to evaluate whether or not the mode of inoculation or the number of applied microorganisms influences plant response. The most pronounced bacterial-induced effect was found for biomass production, and the soil inoculation treatment (using 10(6) CFUs mL(-1)) led to the highest increase in shoot dry weight yield (up to 45%). Bacterial-induced effects on shoot metal concentrations were less pronounced; although a positive effect was found on shoot Pb concentration when using 10(8) CFUs mL(-1) in the soil inoculation (29% increase) and in the seed+soil inoculation (34% increase). Also shoot Zn concentration increased by 24% after seed inoculation with 10(6) CFUs mL(-1). The best effects on the total metal yield were not correlated with an increasing number of inoculated bacteria. In fact the best results were found after a single soil inoculation using the lower cellular density of 10(6) CFUs mL(-1).


Subject(s)
Agricultural Inoculants/physiology , Nicotiana/metabolism , Nicotiana/microbiology , Rhodococcus/physiology , Soil Pollutants/metabolism , Agricultural Inoculants/growth & development , Biodegradation, Environmental , Cadmium/analysis , Cadmium/metabolism , Plant Shoots/chemistry , Plant Shoots/metabolism , Rhodococcus/growth & development , Soil Microbiology , Soil Pollutants/analysis , Nicotiana/chemistry , Nicotiana/growth & development
6.
Environ Pollut ; 193: 205-215, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25058419

ABSTRACT

Intra-specific variability of root biomass production (RP) of six rooted macrophytes, i.e. Juncus effusus, Phragmites australis, Schoenoplectus lacustris, Typha latifolia, Phalaris arundinacea, and Iris pseudacorus grown from clones, in response to Cu exposure was investigated. Root biomass production varied widely for all these macrophytes in control conditions (0.08 µM) according to the sampling site. Root biomass production of T. latifolia and I. pseudacorus in the 2.5-25 µM Cu range depended on the sampling location but not on the Cu dose in the growth medium. For P. australis, J. effusus, S. lacustris, and P. arundinacea, an intra-specific variability of RP depending on both the sampling location and the Cu-dose was evidenced. This intra-specific variability of RP depending on the sampling location and of Cu-tolerance for these last four species suggests that Cu constitutive tolerance for all rooted macrophytes is not a species-wide trait but it exhibits variability for some species.


Subject(s)
Biomass , Copper/metabolism , Cyperaceae/growth & development , Magnoliopsida/growth & development , Plant Roots/growth & development , Poaceae/growth & development , Cyperaceae/metabolism , Magnoliopsida/metabolism , Plant Roots/metabolism , Poaceae/metabolism
7.
Sci Total Environ ; 494-495: 1-8, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25016589

ABSTRACT

The application of plant growth regulators (PGRs) or phytohormones could be an interesting option for stimulating biomass production of hyperaccumulating plants and, consequently, their metal phytoextraction capacity. The effect of exogenous applications of phytohormones (PGR) on the Ni phytoextraction capacity of four Ni hyperaccumulating species (Alyssum corsicum, Alyssum malacitanum, Alyssum murale and Noccaea goesingense) was evaluated. Four different commercially available phytohormones (B, C, K and P) based on gibberellins, cytokinins and auxins were applied to the plant aerial tissues. Each product was applied at three different concentrations (B1-3, C1-3, K1-3 and P1-3). The effect on biomass production was dependent on the species, the PGR type and the concentration at which it was applied. Two of the four products (K and P) consistently increased biomass production compared to untreated control plants in all four plant species. On the other hand, all four products led to a significant increase in the number of branches (and leaves in the case of N. goesingense) of all four species compared to control plants. Application of phytohormones generally led to a reduction in shoot Ni concentration. Nonetheless, in some cases as a consequence of the increase observed in biomass after the application of phytohormones a significant increase in the Ni phytoextraction efficiency was also observed (but this was species- and PGR type-dependent). The results show that PGRs can be successfully used to improve the growth and biomass production of hyperaccumulating species such as Alyssum and Noccaea. However, an increase in biomass did not always lead to a higher Ni removal, and the most effective PGR for increasing Ni removal was the IAA-based product.


Subject(s)
Nickel/metabolism , Plant Development/drug effects , Plant Growth Regulators/metabolism , Soil Pollutants/metabolism , Biodegradation, Environmental , Nickel/analysis , Soil Pollutants/analysis
8.
BMJ Qual Saf ; 22(8): 681-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23722055

ABSTRACT

INTRODUCTION: Diabetes is a chronic disease amenable to management in the community and outpatient setting. The increasing incidence of diabetes places outpatient endocrinology services under pressure to provide a quality service in a timely manner. Our aim was to apply lean thinking to the diabetes clinic in a tertiary referral centre in the West of Ireland to improve flow, as reflected in reduced patient journey times. METHODS: The project lasted 6 months, from January to June 2011. An introductory seminar on lean thinking was arranged to inform and motivate the Diabetes Day Centre staff. Two 'rapid improvement events' took place. Value stream mapping (VSM) was the predominant lean tool employed. Patient journeys were mapped and quantified (minutes) using timesheets allocated to each step in the process at baseline, and following intervention. Data were analysed using Minitab V.16.0. RESULTS: VSM allowed the value-adding and problem-causing steps in the patient journey through the diabetes clinic process to be identified and addressed. Total patient journey time through the clinic was significantly reduced from 118 (± 38.02) min to 58 (± 18.30) min (p<0.001). CONCLUSIONS: This project reflects the successful application of VSM as a lean tool in a pilot study at our institution as evidenced by improved patient flow and a significant reduction in patient journey time through the clinic. Through the incorporation of Lean into the ethos of the hospital, we have the potential to deliver excellent care in a safe environment and in an efficient manner, while benefiting the patient, employees and tax-payer.


Subject(s)
Diabetes Mellitus/therapy , Tertiary Care Centers/organization & administration , Total Quality Management/methods , Workflow , Ambulatory Care , Humans , Ireland , Pilot Projects , Quality Improvement
9.
Int J Phytoremediation ; 15(4): 365-75, 2013.
Article in English | MEDLINE | ID: mdl-23488002

ABSTRACT

Recent studies have shown that application of phytohormones to shoots of Alyssum murale increased biomass production but did not increase Ni shoot concentration. Increased biomass and Ni phytoextraction efficiency is useful to achieve economically viable phytomining. The objective of this study was to evaluate the effect of two types of phytohormones on the Ni phytoextraction capacity of four Alyssum species. Two different commercially available phytohormones (Cytokin and Promalin) based on cytokinins and/or gibberellins were applied on shoot biomass of four Ni hyperaccumulating Alyssum species (A. corsicum, A. malacitanum, A. murale, and A. pintodasilvae). Cytokin was applied in two concentrations and promalin in one concentration. The application of phytohormones had no clear positive effect on biomass production, Ni accumulation and Ni phytoextraction efficiency in the studied Alyssum species. A. malacitanum was the only species in which a significantly negative effect of these treatments was observed (in Ni uptake). A slightly positive response to promalin treatment was observed in the biomass production and Ni phytoextraction efficiency of A. corsicum. Although this effect was not significant it does indicate a potential application of these approaches to improve phytoextraction ability. Further studies will be needed to identify the most adequate phytohormone treatment as well as the appropriate concentrations and application times.


Subject(s)
Brassicaceae/drug effects , Cytokinins/pharmacology , Gibberellins/pharmacology , Metals/metabolism , Nickel/metabolism , Plant Growth Regulators/pharmacology , Biodegradation, Environmental , Biomass , Brassicaceae/growth & development , Brassicaceae/metabolism , Metals/analysis , Nickel/analysis , Oregon , Plant Shoots/drug effects , Plant Shoots/growth & development , Plant Shoots/metabolism , Seedlings/drug effects , Seedlings/growth & development , Seedlings/metabolism , Soil , Soil Pollutants/metabolism
10.
J Hazard Mater ; 217-218: 350-9, 2012 May 30.
Article in English | MEDLINE | ID: mdl-22483595

ABSTRACT

The plant-microorganism-soil system of three pseudometallophytes (Betula celtiberica, Cytisus scoparius and Festuca rubra) growing in a Pb/Zn mine was characterised. Plant metal accumulation, soil metal fractions (rhizosphere and non-vegetated) and bacterial densities were determined. Total Cd, Pb and Zn in non-vegetated soils was up to 50, 3000 and 20,000 mg kg(-1) dry weight, respectively. The residual fraction dominated non-vegetated soils, whereas plant-available fractions became important in rhizosphere soils. All plant species effectively excluded metals from the shoot. F. rubra presented a shoot:root transport factor of ≤0.2 and this population could be useful in future phytostabilisation trials. Culturable bacterial densities and diversity were low (predominantly Actinobacteria). Rhizosphere soils hosted higher total and metal-tolerant bacterial densities. Seventy-four metal-tolerant rhizobacteria were isolated, and characterised genotypically (BOX-PCR, 16S rDNA) and phenotypically [Cd/Zn tolerance, biosurfactant production and plant growth promoting (PGP) traits]. Several isolates resisted high concentrations of Cd and Zn, and only a few presented PGP traits. Fourteen isolates were evaluated for promoting plant growth of two species (Salix viminalis and Festuca pratensis). Thirteen inoculants enhanced growth of F. pratensis, while only three enhanced growth of S. viminalis. Growth enhancement could not always be related to isolate PGP traits. In conclusion, some isolates show potential application in phytostabilisation or phytoextraction techniques.


Subject(s)
Bacteria/metabolism , Lead/metabolism , Mining , Plants/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Zinc/metabolism , Plants/microbiology
11.
Int J Phytoremediation ; 13 Suppl 1: 229-44, 2011.
Article in English | MEDLINE | ID: mdl-22046762

ABSTRACT

Bacterial strains were isolated from the rhizosphere of three populations of the Ni-hyperaccumulator Alyssum serpyllifolium subsp. lusitanicum (A. pintodasilvae; M, S, and L), one population of Ni-hyperaccumulator A. serpyllifolium subsp. malacitanum (A. malacitanum; SB), and one population of the non-hyperaccumulator A. serpyllifolium subsp. serpyllifolium (A. serpyllifolium; SN). Isolates were characterized genotypically by BOX-PCR genomic DNA fingerprinting and comparative sequence analysis of partial 16S rRNA gene, and phenotypically by their Ni tolerance (0-10 mM), presence of plant growth promoting traits (indoleacetic acid (IAA)-, siderophore-, or organic acid-production, and phosphate solubilization) or capacity to produce biosurfactants. Among the collection of rhizobacteria, 84 strains were selected (according to their BOX-PCR profiles and phenotypic characteristics) to assess their ability to modify Ni extractability from Ni-rich (serpentine) soils. Metabolites produced by 13 of the isolates mobilized soil Ni (originating from the rhizosphere of both Ni-hyperaccumulators and non-hyperaccumulator). In contrast, Ni extraction using culture medium filtrates which had supported the growth of 29 strains was significantly reduced. The remaining strains had no effect on Ni mobility. Bacterial induced Ni mobilization was not related to Ni resistance or the phenotypic traits tested. Isolates with potential use in phytoremediation techniques will be further studied in a plant-microorganism-soil system.


Subject(s)
Brassicaceae/microbiology , Nickel/metabolism , Rhizobiaceae/isolation & purification , Rhizobiaceae/metabolism , Biodegradation, Environmental , Brassicaceae/metabolism , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Genotype , Indoleacetic Acids , Phylogeny , Plant Leaves/metabolism , Plant Leaves/microbiology , Plant Roots/metabolism , Plant Roots/microbiology , RNA, Ribosomal, 16S/genetics , Rhizobiaceae/classification , Rhizosphere , Soil , Soil Pollutants/metabolism
12.
Int J Phytoremediation ; 11(6): 525-41, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19810353

ABSTRACT

In this study we determine culturable microbial densities (total heterotrophs, ammonifiers, amylolytics and cellulolytics) and bacterial resistance to Co, Cr, and Ni in bulk and rhizosphere soils of three populations of the Ni-hyperaccumulator Alyssum serpyllifolium subsp. lusitanicum and the excluder Dactylis glomerata from ultramafic sites (two populations in Northeast (NE) Portugal (Samil (S), Morais (M)) and one population in Northwest (NW) Spain (Melide (L)). The relationship between bioavailable metal concentrations (H2O-soluble) and microbial densities were analysed. Significant differences in microbial densities and metal-resistance were observed between the two species and their three populations. The hyperaccumulator showed higher microbial densities (except cellulolytics) and a greater rhizosphere effect, but this was only observed in S and M populations. These populations of A. serpyllifolium also showed selective enrichment of Ni-tolerant bacteria at the rhizosphere where Ni solubility was enhanced (densities of Ni-resistant bacteria were positively correlated with H2O-soluble Ni). These rhizobacteria could solubilise Ni in the soil and potentially improve phytoextraction strategies.


Subject(s)
Brassicaceae/metabolism , Brassicaceae/microbiology , Nickel/metabolism , Plant Roots/metabolism , Plant Roots/microbiology , Trace Elements/toxicity , Biodegradation, Environmental , Environmental Monitoring , Geologic Sediments , Nickel/chemistry , Soil/analysis , Soil Pollutants/chemistry , Soil Pollutants/metabolism
13.
Chemosphere ; 66(8): 1458-67, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17109934

ABSTRACT

Amendment of agricultural soils with municipal sewage sludges provides a valuable source of plant nutrients and organic matter. Nevertheless, addition of heavy metals and risks of eutrophication continue to be of concern. Metal behaviour in soils and plant uptake are dependent on the nature of the metal, sludge/soil physico-chemical properties and plant species. A pot experiment was carried out to evaluate plant production and heavy metal uptake, soil heavy metal pools and bioavailability, and soil P pools and possible leaching losses, in agricultural soils amended with sewage sludge for at least 10 years (F20) compared to non-amended soils (control). Sewage sludge application increased soil pH, N, Olsen-extractable-P, DOC and exchangeable Ca, Mg and K concentrations. Total and EDTA-extractable soil concentrations of Cu and Zn were also significantly greater in F20, and soil metal (Cu, Mn and Zn) and P fractionation altered. Compared to the control, in F20 relative amounts of acid-extractable (Mn, Zn), reducible (Mn, Zn) and oxidisable (Cu, Zn) metal fractions were greater, and a dominance of inorganic P forms was observed. Analyses of F20 soil solutions highlighted risks of PO4 and Cu leaching. However, despite the observed increases in metal bioavailability sewage sludge applications did not lead to an increase in plant shoot concentrations (in wild plants or crop species). On the contrary, depending on the plant species, Mn and Zn tissue concentrations were within the deficiency level for most plants.


Subject(s)
Metals, Heavy/metabolism , Phosphorus/metabolism , Plants/metabolism , Sewage , Soil , Biomass , Copper/metabolism , Manganese/metabolism , Plant Development , Zinc/metabolism
14.
Sci Total Environ ; 354(2-3): 265-77, 2006 Feb 01.
Article in English | MEDLINE | ID: mdl-16399000

ABSTRACT

Phytoremediation techniques are now considered to be promising alternatives to conventional techniques for the remediation of diffused or moderately contaminated soils. Despite their growing acceptance relatively few plant species have been studied for phytoremediation purposes. Further geobotanical surveys and plant screenings are necessary since these could lead to the identification of additional species with potential value for such applications. Serpentine areas could prove valuable sources of such plants. In this study heavy metal accumulation was determined in the flora associated with ultramafic and non-ultramafic soils of the Trás-os-Montes region of NE Portugal. Study sites were selected to represent a wide range of soil-forming rocks (serpentinized (S), ultrabasic (UB), basic (B) and acid (migmatite, M and schists, SC) rocks) and plant metal accumulation was related to soil metal bioavailability. Nine plant species (representing 7 families) were sampled including the Ni hyperaccumulator Alyssum serpyllifolium subsp. lusitanicum. The greatest metal accumulation, transport (leaf[metal]:root[metal]) and bioaccumulation (leaf[metal]/soil[metal]) was found in four of the non metal-hyperaccumulating species: Cistus ladanifer, Lavandula stoechas, Plantago subulata subsp. radicata and Thymus mastichina. Metal accumulation depended on both the plant species and the edaphic conditions at its provenance. While P. subulata is of less interest due to its low biomass the remaining three species could be of use in phytoremediation technologies such as phytoextraction, and particularly in soils contaminated with Cr, Mn and Zn. These three species are also of economic interest due to their oil and fragrance producing biomass.


Subject(s)
Magnoliopsida/metabolism , Metals, Heavy/metabolism , Soil Pollutants/metabolism , Biodegradation, Environmental , Geological Phenomena , Geology , Metals, Heavy/analysis , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Roots/chemistry , Plant Roots/metabolism , Plant Stems/chemistry , Plant Stems/metabolism , Portugal , Soil Pollutants/analysis
15.
Sci Total Environ ; 336(1-3): 1-11, 2005 Jan 05.
Article in English | MEDLINE | ID: mdl-15589245

ABSTRACT

The efficiency of Alyssum serpyllifolium ssp. lusitanicum (Brassicaceae) for use in phytoextraction of polymetallic contaminated soils was evaluated. A. serpyllifolium was grown on two mine-spoil soils (MS1 and MS2): MS1 is contaminated with Cr (283 mg kg(-1)) and MS2 is moderately contaminated with Cr (263 mg kg(-1)), Cu (264 mg kg(-1)), Pb (1433 mg kg(-1)) and Zn (377 mg kg(-1)). Soils were limed to about pH 6.0 (MS1/Ca and MS2/Ca) or limed and amended with NPK fertilisers (MS1/NPK and MS2/NPK). Biomass was reduced on MS2/Ca due to Cu phytotoxicity. Fertilisation increased biomass by 10-fold on MS1/NPK, but root growth was reduced by 7-fold compared with MS1/Ca. Plants accumulated Mn, Ni and Zn in shoots, and both metal content and transportation were generally greater in MS2 than in MS1. Zinc bioaccumulation factors (BF, shoot([metal])/soil([metal])) were significantly greater in MS2 than in MS1. However, metal yields were greatest in plants grown on MS1/NPK. Concentrations of EDTA-, NH(4)Cl- and Mehlich 3 (M3)-extractable Mn and Zn were greater after plant growth. Concentrations of M3-extractable Cr, Ni, Pb and Zn were increased at the rhizosphere. Sequential extractions showed changes in the metal distribution among different soil fractions after growth. This could reflect the buffering capacity of these soils or the plants' ability to mobilise metals from less plant-available soil pools. Results suggest that A. serpyllifolium could be suitable for phytoextraction uses in polymetallic-contaminated soils, provided Cu concentrations were not phytotoxic. However, further optimisation of growth and metal extraction are required.


Subject(s)
Brassicaceae/chemistry , Metals, Heavy/isolation & purification , Soil Pollutants/isolation & purification , Biodegradation, Environmental , Biological Availability , Brassicaceae/growth & development , Metals, Heavy/pharmacokinetics , Mining , Soil Pollutants/pharmacokinetics , Spain , Tissue Distribution
16.
J Agric Saf Health ; 9(4): 275-83, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14679876

ABSTRACT

The Agricultural Disability Awareness and Risk Education Project (AgDARE) is a research-based curriculum of agricultural safety instruction based on Prochaska and DiClemente's Transtheroetical Model of Change. The program uses eight reality-based psychomotor and narrative modules to teach safe farm work behaviors. In addition to in-class pencil and paper assessments on safety attitudes and behavior intention, farm visits were made to assess the longer term influence of AgDARE. Visits were made between 11 and 20 months (mean = 14.24 months) after completion of the classroom instruction to 29 students who worked on farms and completed at least one-half of the AgDARE instruction. All but one of the visited students exhibited safe work behaviors addressed by the AgDARE instruction. In addition, 76% of the visited students had made positive changes in their farm work behavior since participating in AgDARE. Changes extended beyond the instruction that students received in class to include other aspects of farm work and other family members. The use of farm visits to evaluate students' safety behaviors was tempered by the challenge of contacting students and obstacles associated with observing work in an environment where little is routine or regular.


Subject(s)
Accidents, Occupational/prevention & control , Adolescent Behavior/psychology , Agriculture/education , Health Knowledge, Attitudes, Practice , Occupational Health , Primary Prevention/education , Teaching/methods , Adolescent , Health Education/methods , Humans , Iowa , Kentucky , Mississippi , Problem-Based Learning , Risk-Taking , School Health Services
17.
Occup Med (Lond) ; 53(4): 279-86, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12815126

ABSTRACT

BACKGROUND: Back- and fall-related injuries occur frequently in construction and are costly in terms of workers' compensation claims and lost productivity. Interventions are needed that address the susceptibility to these injuries. AIMS: The purpose of this study was to develop and test a safety training intervention for small construction companies (

Subject(s)
Accidental Falls/prevention & control , Accidents, Occupational/prevention & control , Back Injuries/prevention & control , Health Education/standards , Occupational Health Services/standards , Case-Control Studies , Humans
18.
Emerg Med J ; 20(2): 138-42, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12642526

ABSTRACT

INTRODUCTION: Observation and assessment wards allow patients to be observed on a short-term basis and permit patient monitoring and/or treatment for an initial 24-48 hour period. They should permit concentration of emergency activity and resources in one area, and so improve efficiency and minimise disruption to other hospital services. These types of ward go under a variety of names, including observation, assessment, and admission wards. This review aims to evaluate the current literature and discuss assessment/admission ward functionality in terms of organisation, admission criteria, special patient care, and cost effectiveness. METHODS: Search of the literature using the Medline and BIDS databases, combined with searches of web based resources. Critical assessment of the literature and the data therein is presented. RESULTS: The advantages and disadvantages of the use of assessment/admission wards were assessed from the current literature. Most articles suggest that these wards improve patient satisfaction, are safe, decrease the length of stay, provide earlier senior involvement, reduce unnecessary admissions, and may be particularly useful in certain diagnostic groups. A number of studies summarise their organisational structure and have shown that strong management, staffing, organisation, size, and location are important factors for efficient running. There is wide variation in the recommended size of these wards. Observation wards may produce cost savings largely relating to the length of stay in such a unit. CONCLUSION: All types of assessment/admission wards seem to have advantages over traditional admission to a general hospital ward. A successful ward needs proactive management and organisation, senior staff involvement, and access to diagnostics and is dependent on a clear set of policies in terms of admission and care. Many diagnostic groups benefit from this type of unit, excluding those who will inevitably need longer admission. Vigorous financial studies have yet to be undertaken in the UK. Definitions of observation, assessment, and admission ward are suggested.


Subject(s)
Emergency Service, Hospital/organization & administration , Observation , Patients' Rooms , Cost-Benefit Analysis , Health Services Research , Humans , Length of Stay , Patient Admission
19.
Inj Prev ; 7 Suppl 1: i59-63, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11565974

ABSTRACT

OBJECTIVE: Develop and test a farm health and injury prevention educational intervention for high school agriculture students. SETTING: Twenty one high schools in Kentucky, Iowa, and Mississippi. METHODS: A quasiexperimental crossover design was used to test the effectiveness of two sets of instructional materials designed through participatory action research with agriculture teachers and students. Narrative simulations based on farm work stories and simulations of farm work while students pretended to have a disability were completed in 14 schools (n = 373) over the academic year. Students in seven control schools (n = 417) received no intervention but completed, in the same time frame as students in the treatment schools, demographic surveys and premeasures and post-measures of farm safety attitudes and intent to change safety behaviors. One year after the intervention, 29 students from the treatment group received farm visits to measure their farm safety behaviors. RESULTS: Students engaged in hazardous work on farms. Thirty two were involved in tractor overturns and 11 had received injuries from rotating power take-off mechanisms. One fourth reported hearing problems, and 21% had respiratory symptoms after working in dusty farm surroundings. Students who completed at least two physical and two narrative simulations of the Agricultural Disability Awareness and Risk Education (AgDARE) curriculum showed statistically significant positive changes in farm safety attitude and intent to change behaviors. CONCLUSIONS: Adolescents engage in farm work that places them at risk for injury and illness. The AgDARE curriculum may be an effective and efficient method of teaching farm safety in high school agriculture classes.


Subject(s)
Agriculture , Health Education , Health Knowledge, Attitudes, Practice , Primary Prevention/education , Wounds and Injuries/prevention & control , Accident Prevention , Adolescent , Cross-Over Studies , Disabled Persons , Female , Humans , Iowa , Kentucky , Male , Mississippi , Risk Assessment , Safety , Sampling Studies , Students
20.
J Exp Bot ; 52(359): 1339-52, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11432953

ABSTRACT

Aluminium (Al) toxicity is widely considered to be the most important growth-limiting factor for plants in strongly acid soils (pH<5.0). The inhibition of root elongation in three varieties of maize (Zea mays L. vars Clavito, HS701b and Sikuani) was followed over the first 48 h of Al treatment, and during the initial 10 h elongation was determined on an hourly basis. The silicon (Si)-induced amelioration of Al toxicity was investigated by pre-treating seedlings for 72 h in nutrient solutions with 1000 microM Si before transfer into solutions with 0, 20 or 50 microM Al (without Si). Plants were either grown in complete low ionic strength nutrient solutions (CNS) or in low salt solutions of 0.4 mM CaCl2 (LSS). In addition, the role of root exudation of organic compounds as a mechanism of Si-induced alleviation of Al toxicity was investigated. Aluminium-induced inhibition of root elongation in the maize var. HS701b was observed within 1 h of Al exposure. After a lag time of at least 8 h, Si-induced alleviation of Al toxicity was observed in this variety when grown in LSS. In the Al-resistant var. Sikuani, Al-resistance was only observed after exposure to 50 microM Al, and not after exposure to 20 microM Al, suggesting that there exists a threshold Al concentration before the mechanisms of Al resistance are activated. Aluminium stimulated root exudation of oxalic acid in all three varieties, but exudate concentrations did not increase with either Al resistance or with Si pretreatment. Aluminium and Si triggered release of catechol and of the flavonoid-type phenolics: catechin, and quercetin. In the Al-resistant variety, Sikuani, Al-exposed plants pretreated with Si exuded up to 15 times more phenolics than those plants not pretreated with Si. The flavonoid-type phenolics, to date unconsidered, appear to play a role in the mechanism(s) of Si-induced amelioration of Al toxicity.


Subject(s)
Aluminum/toxicity , Plant Roots/drug effects , Silicon/pharmacology , Zea mays/drug effects , Aluminum/metabolism , Anions/metabolism , Calcium Chloride/pharmacology , Carboxylic Acids/chemistry , Carboxylic Acids/metabolism , Catechin/analogs & derivatives , Catechin/metabolism , Citric Acid/metabolism , Drug Resistance , Oxalates/metabolism , Phenols/metabolism , Plant Roots/growth & development , Plant Roots/physiology , Quercetin/metabolism , Soil , Zea mays/growth & development , Zea mays/physiology
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