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1.
New Phytol ; 242(3): 1000-1017, 2024 May.
Article in English | MEDLINE | ID: mdl-38433329

ABSTRACT

Drought affects the complex interactions between Norway spruce, the bark beetle Ips typographus and associated microorganisms. We investigated the interplay of tree water status, defense and carbohydrate reserves with the incidence of bark beetle attack and infection of associated fungi in mature spruce trees. We installed roofs to induce a 2-yr moderate drought in a managed spruce stand to examine a maximum of 10 roof and 10 control trees for resin flow (RF), predawn twig water potentials, terpene, phenolic and carbohydrate bark concentrations, and bark beetle borings in field bioassays before and after inoculation with Endoconidiophora polonica and Grosmannia penicillata. Drought-stressed trees showed more attacks and significantly longer fungal lesions than controls, but maintained terpene resin defenses at predrought levels. Reduced RF and lower mono- and diterpene, but not phenolic concentrations were linked with increased host selection. Bark beetle attack and fungi stimulated chemical defenses, yet G. penicillata reduced phenolic and carbohydrate contents. Chemical defenses did not decrease under mild, prolonged drought in our simulated small-scale biotic infestations. However, during natural mass attacks, reductions in carbon fixation under drought, in combination with fungal consumption of carbohydrates, may deplete tree defenses and facilitate colonization by I. typographus.


Subject(s)
Coleoptera , Picea , Weevils , Animals , Droughts , Picea/microbiology , Plant Bark/chemistry , Plant Diseases/microbiology , Terpenes , Phenols , Norway , Water/analysis , Carbohydrates/analysis
2.
Genes Cancer ; 13: 60-71, 2022.
Article in English | MEDLINE | ID: mdl-36471782

ABSTRACT

Tumor-associated inflammation and chromosomal aberrations can play crucial roles in cancer development and progression. In neuroblastoma (NB), the enzyme cyclooxygenase-2 (COX-2) is associated with copy number alterations on the long arm of chromosome 11 (Ch 11q), defining an aggressive disease subset. This retrospective study included formalin-fixed paraffin-embedded tumor samples collected from nine patients during diagnosis at the pediatric Pequeno Principe Hospital, Curitiba, PR, Brazil, and post-chemotherapy (CT). COX-2 expression was evaluated using immunohistochemistry and correlated with the genome profile of paired pre- and post-CT samples, determined by array comparative genomic hybridization. A systems biology approach elucidated the PTGS2 network interaction. The results showed positive correlations between pre-CT Ch 7q gain and COX-2 expression (ρ = 0.825; p-value = 0.006) and negative correlations between Ch 7q gain and Ch 11q deletion (ρ = -0.919; p-value = 0.0005). Three samples showed Ch 11q deletion and Ch 7q gain. Network analysis identified a direct connection between CAV-1 (Ch 7q) and COX-2 in NB tumors and highlighted the connection between amplified genes in Ch 7q and deleted ones in 11q. The identification of hub-bottleneck-switch genes provides new biological insights into this connection between NB, tumorigenesis, and inflammation.

3.
Molecules ; 27(13)2022 Jun 23.
Article in English | MEDLINE | ID: mdl-35807301

ABSTRACT

Multidimensional gas chromatography is, presently, an established and powerful analytical tool, due to higher resolving power than the classical 1D chromatographic approaches. Applied to multiple areas, it allows to isolate, detect and identify a larger number of compounds present in complex matrices, even in trace amounts. Research was conducted to determine which compounds, emitted by host plants of the eucalyptus weevil, Gonipterus platensis, might mediate host selection behavior. The identification of a pheromone blend of G. platensis is presented, revealing to be more attractive to weevils of both sexes, than the individual compounds. The volatile organic compounds (VOCs) were collected by headspace solid phase microextraction (HS-SPME), MonoTrapTM disks, and simultaneous distillation-extraction (SDE). Combining one dimensional (1D) and two-dimensional (2D) chromatographic systems-comprehensive and heart-cut two-dimensional gas chromatography (GC×GC and H/C-MD-GC, respectively) with mass spectrometry (MS) and electroantennographic (EAD) detection, enabled the selection and identification of pertinent semiochemicals which were detected by the insect antennal olfactory system. The behavioral effect of a selected blend of compounds was assessed in a two-arm olfactometer with ten parallel walking chambers, coupled to video tracking and data analysis software. An active blend, composed by cis and trans-verbenol, verbenene, myrtenol and trans-pinocarveol was achieved.


Subject(s)
Eucalyptus , Volatile Organic Compounds , Weevils , Animals , Cues , Female , Gas Chromatography-Mass Spectrometry/methods , Insecta , Male , Pheromones/chemistry , Solid Phase Microextraction , Trees , Volatile Organic Compounds/analysis
4.
Sci Total Environ ; 802: 149671, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34454147

ABSTRACT

The usage of reclaimed wastewater (RWW) for irrigation of agricultural soils is increasingly being acknowledged for reducing water consumption by promoting reuse of treated wastewater, and for the delivery of extant nutrients in the soil. The downside is that RWW may be a vector for contamination of soils with contaminants of emerging concern (CECs), if left uncontrolled. Its usage is anticipated to alter the soil properties, consequently also the soil microbial community. In the present study, soil microcosms were set to monitor how short periods (up to fourteen days) of RWW irrigation influence the soil ecosystem, namely its physicochemical properties, functioning, and colonising microbiota (differentiating fungi from bacteria). Two scenarios were studied: clean soil and soil contaminated (spiked) with 9 CECs, at conditions that limit any abiotic decay processes, monitoring along time fluctuations in the taxonomic and functional microbiota diversity. As shortly as fourteen days, the irrigation of either soil with RWW did not significantly (p > 0.05) alter its physicochemical properties and scarcely impacted the bioremediation processes of the CECs that showed decay levels ranging from 24% to 100%. Bacillus spp. dominance was enhanced along time in all the soil microcosms (reaching over 70% of the total abundance on the 7th day) but the RWW help to preserve, to some extent, high bacterial diversity. Besides, irrigation with RWW acted as a buffer of the soil mycobiota, limiting alterations in its composition caused either along time (to a minor degree) or due to contamination with CECs (to a great degree). This includes limiting the rise of Rhizopus sp. relative abundance. Collectively, our data support the utility of short-term periods of RWW irrigation for preserving the soil microbial diversity and functioning, especially when fungi are considered.


Subject(s)
Microbiota , Wastewater , Agricultural Irrigation , Soil , Soil Microbiology , Wastewater/analysis
5.
J Hazard Mater ; 406: 124304, 2021 03 15.
Article in English | MEDLINE | ID: mdl-33153782

ABSTRACT

This study analyses the electrokinetic (EK) contribution to the removal from a clay soil of a mixture of 10 different contaminants of emerging concern (CECs; 17ß-estradiol, E2; sulfamethoxazole, SMX; bisphenol A, BPA; ibuprofen, IBU; 17α-ethinylestradiol, EE2; oxybenzone, OXY; diclofenac, DCF; triclosan, TCS; caffeine, CAF; carbamazepine, CBZ). After 4 days, the CECs natural attenuation was between 0% (CBZ) and 90% (E2) yet increasing with the application of EK (20 mA, 12 h ON/OFF) to 14% (CBZ) and 100% (E2). When EK was applied, the CECs more recalcitrant to biodegradation (i.e. ≤ 13% biotic decay) mostly underwent electro-chemical induced degradation (OXY, DCF, TCS, CAF, CBZ). Daily irrigation enhanced the rates of the electro-oxidation -osmosis and -migration, increasing the CECs decay. After 8 days of EK treatment, the CECs decay increased, surpassing the decay lag phase of some compounds (OXY, TCS, and CBZ). Yet after 16 days, most CECs showed similar removals with and without EK, with EK only acting positively on SMX, OXY, TCS and CBZ (ca. +10%). Our results support that EK application can improve the removal of CECs from soil, however, under the conditions tested, 16-day treatment lead to pH alterations that decreased the bioremediation efficiency and inhibited electro-degradation near the cathode.


Subject(s)
Environmental Restoration and Remediation , Soil Pollutants , Triclosan , Biodegradation, Environmental , Soil , Soil Pollutants/analysis
6.
Sci Total Environ ; 743: 140544, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32652356

ABSTRACT

The effluent reuse for soil irrigation is foreseen as a possible strategy to mitigate the pressure on water resources. However, there is the risk of potential accumulation in soil of emerging organic contaminants (EOCs). In the present work the electrokinetic remediation (EKR) technology, use of direct current, was applied for the removal of EOCs from a soil irrigated with effluent. For this, a soil collected from a rice field (located in Portugal) was mixed with spiked effluent to simulate flood irrigation in one time-period. The experiments were carried out for 6 days applying a low current intensity of 2.5 mA. Different current strategies were tested: continuous mode, reversed electrode polarization (REP), On/Off time periods, and the combination of the last two. The target EOCs comprises a list of six pharmaceuticals and personal care products widely detected in treated wastewater. This study showed that once introduced in soil through effluent irrigation, 20-100% of the EOCs were still present in the soil after 6 days. EKR enhanced up to 20% of the EOCs removal when comparing with control (without current). The EOC removals showed to be related to the microcosm location (anode, central or cathode sections) and dependent of EOCs characteristics. Soil characteristics did not change when On/Off system was combined with REP as a current strategy, and a more homogenous removal of the studied EOCs was achieved in the tested conditions. EKR showed to be a promising technology to be applied in EOCs contaminated soils, not only for removal purposes, but also to avoid possible dispersion in the environment.

7.
Nanomaterials (Basel) ; 10(4)2020 Mar 29.
Article in English | MEDLINE | ID: mdl-32235407

ABSTRACT

Triclosan (TCS) is a bacteriostatic used in household items that promotes antimicrobial resistance and endocrine disruption effects both to humans and biota, raising health concerns. In this sense, new devices for its continuous monitoring in complex matrices are needed. In this work, sensors, based on polyelectrolyte layer-by-layer (LbL) films prepared onto gold interdigitated electrodes (IDE), were studied. An electronic tongue array, composed of (polyethyleneimine (PEI)/polysodium 4-styrenesulfonate (PSS))5 and (poly(allylamine hydrochloride/graphene oxide)5 LbL films together with gold IDE without coating were used to detect TCS concentrations (10-15-10-5 M). Electrical impedance spectroscopy was used as means of transduction and the obtained data was analyzed by principal component analysis (PCA). The electronic tongue was tested in deionized water, mineral water and wastewater matrices showing its ability to (1) distinguish between TCS doped and non-doped solutions and (2) sort out the TCS range of concentrations. Regarding film stability, strong polyelectrolytes, as (PEI/PSS)n, presented more firmness and no significant desorption when immersed in wastewater. Finally, the PCA data of gold IDE and (PEI/PSS)5 sensors, for the mineral water and wastewater matrices, respectively, showed the ability to distinguish both matrices. A sensitivity value of 0.19 ± 0.02 per decade to TCS concentration and a resolution of 0.13 pM were found through the PCA second principal component.

8.
Chemosphere ; 247: 125758, 2020 May.
Article in English | MEDLINE | ID: mdl-31931309

ABSTRACT

Degradation technologies applied to emerging organic contaminants from human activities are one of the major water challenges in the contamination legacy. Triclosan is an emerging contaminant, commonly used as antibacterial agent in personal care products. Triclosan is stable, lipophilic and it is proved to have ecotoxicologic effects in organics. This induces great concern since its elimination in wastewater treatment plants is not efficient and its by-products (e.g. methyl-triclosan, 2,4-dichlorophenol or 2,4,6-trichlorophenol) are even more hazardous to several environmental compartments. This work provides understanding of two different electrochemical reactors for the degradation of triclosan and its derivative by-products in effluent. A batch reactor and a flow reactor (mimicking a secondary settling tank in a wastewater treatment plant) were tested with two different working anodes: Ti/MMO and Nb/BDD. The degradation efficiency and kinetics were evaluated to find the best combination of current density, electrodes and set-up design. For both reactors the best electrode combination was achieved with Ti/MMO as anode. The batch reactor at 7 mA/cm2 during 4 h attained degradation rates below the detection limit for triclosan and 2,4,6-trichlorophenol and, 94% and 43% for 2,4-dichlorophenol and methyl triclosan, respectively. The flow reactor obtained, in approximately 1 h, degradation efficiencies between 41% and 87% for the four contaminants. This study suggests an alternative technology for emerging organic contaminants degradation, since the combination of a low current density with the flow and matrix induced disturbance increases and speeds up the compounds' elimination in a real environmental matrix.


Subject(s)
Electrochemical Techniques/instrumentation , Organic Chemicals/chemistry , Triclosan/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Electrodes , Humans , Kinetics , Phenols/chemistry , Triclosan/analogs & derivatives
9.
Sensors (Basel) ; 19(24)2019 Dec 04.
Article in English | MEDLINE | ID: mdl-31817207

ABSTRACT

Triclosan, which is a bacteriostatic used in household items, has raised health concerns, because it might lead to antimicrobial resistance and endocrine disorders in organisms. The detection, identification, and monitoring of triclosan and its by-products (methyl triclosan, 2,4-Dichlorophenol and 2,4,6-Trichlorophenol) are a growing need in order to update current water treatments and enable the continuous supervision of the contamination plume. This work presents a customized electronic tongue prototype coupled to an electrochemical flow reactor, which aims to access the monitoring of triclosan and its derivative by-products in a real secondary effluent. An electronic tongue device, based on impedance measurements and polyethylenimine/poly(sodium 4-styrenesulfonate) layer-by-layer and TiO2, ZnO and TiO2/ZnO sputtering thin films, was developed and tested to track analyte degradation and allow for analyte detection and semi-quantification. A degradation pathway trend was observable by means of principal component analysis, being the sample separation, according to sampling time, explained by 77% the total variance in the first two components. A semi-quantitative electronic tongue was attained for triclosan and methyl-triclosan. For 2,4-Dichlorophenol and 2,4,6-Trichlorophenol, the best results were achieved with only a single sensor. Finally, working as multi-analyte quantification devices, the electronic tongues could provide information regarding the degradation kinetic and concentrations ranges in a dynamic removal treatment.


Subject(s)
Electrochemical Techniques/methods , Food Contamination/analysis , Chlorophenols/analysis , Chlorophenols/isolation & purification , Electrochemical Techniques/instrumentation , Electronic Nose , Polyethyleneimine/chemistry , Polymers/chemistry , Principal Component Analysis , Solid Phase Extraction , Sulfonic Acids/chemistry , Titanium/chemistry , Triclosan/analysis , Triclosan/isolation & purification , Zinc Oxide/chemistry
10.
Environ Pollut ; 253: 625-635, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31330354

ABSTRACT

The potential of electrokinetic (EK) remediation to remove from soils one particular group of contaminants - contaminants of emergent concern (CECs), remains largely overlooked. The present study aimed to evaluate the efficiency of the EK process for the remediation of an agricultural clay soil containing CECs. The soil was spiked with four CECs - sulfamethoxazole, ibuprofen, triclosan and caffeine - and their status (i.e. residual amounts and spatial distribution) evaluated at the seventh day of EK treatment at a defined current intensity, directionality and duration of void period. The characterization of the soil physicochemical properties was also undertaken. The results showed similar degradation trends in all applied EK strategies, which were suchlike to that of the natural attenuation (biotic control): sulfamethoxazole > ibuprofen ≥ triclosan ≥ caffeine. The removal of the CECs was higher under a 10 mA constant current application than in the natural attenuation (up to 2.8 times higher; from 13 to 85%). Caffeine was the exception with its best removal efficiency being achieved when the ON/OFF switch mode with a void period duration of 12 h was used (36%). The use of electro-polarization reversal mode did not favour the remediation. The soil pH variations resulting from EK application were determinant for triclosan remediation, which increased with soil pH increase. The only EK condition that promoted the removal of all CECs was the ON/OFF switch mode of 12 h (removals between 36 and 72%), in which only minor physicochemical disturbances of the soil were observed. This is in accordance with a potential application of EK in-situ. The last is reinforced by the low estimated electrical cost of the best EK technology - 2.33 €/m3 for the 7 days. Overall the EK remediation processes are a promising technology to stimulate in situ the removal of CECs from agricultural soils.


Subject(s)
Environmental Restoration and Remediation/methods , Soil Pollutants/chemistry , Soil/chemistry , Clay , Electricity , Electrochemical Techniques , Soil Pollutants/analysis
11.
Environ Sci Pollut Res Int ; 25(36): 35928-35935, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30191527

ABSTRACT

Pharmaceuticals and personal care products (PPCPs) have attracted increasing concern during the last decade because of their widespread uses and continuous release to the aquatic environment. This work aimed to study the distribution of caffeine (CAF), oxybenzone (MBPh), and triclosan (TCS) when they arrive in salt marsh areas and to assess their remediation potential by two different species of salt marsh plants: Spartina maritima and Halimione portulacoides. Experiments were carried out in the laboratory either in hydroponics (sediment elutriate) or in sediment soaked in elutriate, for 10 days. Controls without plants were also carried out. CAF, MBPh, and TCS were added to the media. In unvegetated sediment soaked in elutriate, CAF was mainly in the liquid phase (83%), whereas MBPh and TCS were in the solid phase (90% and 56%, respectively); the highest remediation was achieved for TCS (40%) and mainly attributed to bioremediation. The presence of plants in sediment soaked in elutriate-enhanced PPCPs remediation, decreasing CAF and TCS levels between approximately 20-30% and MBPh by 40%.. Plant uptake, adsorption to plant roots/sediments, and bio/rhizoremediation are strong hypothesis to explain the decrease of contaminants either in water or sediment fractions, according to PPCPs characteristics.


Subject(s)
Benzophenones/analysis , Caffeine/analysis , Chenopodiaceae/physiology , Poaceae/physiology , Triclosan/analysis , Water Pollutants, Chemical/analysis , Wetlands , Adsorption , Biodegradation, Environmental , Geologic Sediments/chemistry , Hydroponics , Plant Roots/chemistry , Seawater , Water/chemistry
12.
J Hazard Mater ; 358: 467-474, 2018 09 15.
Article in English | MEDLINE | ID: mdl-29759593

ABSTRACT

The present work discusses the efficiency of the electrodialytic (ED) process to remove emerging organic contaminants (EOCs) from effluent. The ED process was carried out in a cell of two-compartments (2 C-cell) with effluent in either the anode or cathode compartment, separated from the electrolyte compartment through an anion or a cation exchange membrane (AEM and CEM, respectively). As effluent destination might be soil irrigation, and having in mind the nutrient recycling, phosphorus was also monitored in the process. The ED removals showed to be dependent of EOCs characteristics and cell design. Removals were higher when using an AEM (60-72%) than a CEM (8-63%), except for caffeine when the effluent was placed in the cathode, that did not show any removal. When using an AEM with the effluent placed in the anode compartment, all the EOCs (including caffeine) were removed between 57-72%, mainly through electrodegradation phenomena. Regarding phosphorus, a polarity switch may be done to a 2 C-cell with a AEM, depending on the effluent final use. This technology is still in its first steps and, in both cases, further optimization of ED parameters is needed. Still, this technological innovation and cross-cutting research envisages the promotion of economic, social and environmental benefits.

13.
Environ Sci Pollut Res Int ; 24(8): 7208-7215, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28101706

ABSTRACT

The present work aimed to evaluate the capacity of constructed wetlands (CWs) to remove three emerging organic contaminants with different physicochemical properties: caffeine (CAF), oxybenzone (MBPh), and triclosan (TCS). The simulated CWs were set up with a matrix of light expanded clay aggregates (LECA) and planted with Spartina maritima, a salt marsh plant. Controlled experiments were carried out in microcosms using deionized water and wastewater collected at a wastewater treatment plant (WWTP), with different contaminant mass ranges, for 3, 7, and 14 days. The effects of variables were tested isolatedly and together (LECA and/or S. maritima). The presence of LECA and/or S. maritima has shown higher removal (around 61-97%) of lipophilic compounds (MBPh and TCS) than the hydrophilic compound (CAF; around 19-85%). This was attributed to the fact that hydrophilic compounds are dissolved in the water column, whereas the lipophilic ones suffer sorption processes promoting their removal by plant roots and/or LECA. In the control (only wastewater), a decrease in the three contaminant levels was observed. Adsorption and bio/rhizoremediation are the strongest hypothesis to explain the decrease in contaminants in the tested conditions.


Subject(s)
Aluminum Silicates/chemistry , Waste Disposal, Fluid , Wastewater/chemistry , Water Pollutants, Chemical , Adsorption , Clay , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification
14.
J Hazard Mater ; 313: 185-92, 2016 08 05.
Article in English | MEDLINE | ID: mdl-27064863

ABSTRACT

Electrically assisted mitigation of coastal sediment oil pollution was simulated in floor-scale laboratory experiments using light crude oil and saline water at approximately 1/10 oil/water (O/W) mass ratio in pore fluid. The mass transport of the immiscible liquid phases was induced under constant direct current density of 2A/m(2), without water flooding. The transient pore water pressures (PWP) and the voltage differences (V) at and in between consecutive ports lined along the test specimen cell were measured over 90days. The oil phase transport occurred towards the anode half of the test specimen where the O/W volume ratio increased by 50% over its initial value within that half-length of the specimen. In contrast, the O/W ratio decreased within the cathode side half of the specimen. During this time, the PWP decreased systematically at the anode side with oil bank accumulation. PWP increased at the cathode side of the specimen, signaling increased concentration of water there as it replaced oil in the pore space. Electrically induced transport of the non-polar, non-conductive oil was accomplished in the opposing direction of flow by displacement in absence of viscous coupling of oil-water phases.

15.
Waste Manag ; 52: 193-201, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27033993

ABSTRACT

Sewage sludge ashes (SSA), although a waste, contain elements with socio-economic and environmental potential that can be recovered. This is the case of phosphorus (P). SSA from two Danish incinerators were collected during two years and characterized. The sampling was done immediately after incineration (fresh SSA) or from an outdoor deposit (deposited SSA). Although morphology and mineral composition were similar, physico-chemical and metal concentration differences were found between incinerator plants and sampling periods. No differences were observed between deposited and fresh SSA, except for the parameters directly influenced by disposal conditions (e.g. moisture content). All the SSAs had high concentrations of P (up to 16wt%), but they all exceeded Danish EPA Cd and Ni thresholds for direct application at agricultural soil. Fresh and deposited SSA were acid washed aiming P extraction, achieving 50gP/kg (approx. 37% of total P), but metals were also co-extracted to the liquid phase. To avoid and/or minimize the metals pollution of the extracted P, selective P recovery from the SSA was tested, using the electrodialytic (ED) process. ED laboratory cells, with 3 compartments (3c) and 2 compartments (2c), and two acid concentrations (H2SO4, 0.08M and 0.19M) were used for 7days. The most concentrated acid solution increased P solubilization. The 2c-cell combined with the higher acid concentration resulted in higher P recoveries, 125g of P/kg of SSA in the anolyte. The obtained results showed that the ED process is a valuable tool for the SSA valorisation as it promotes simultaneous P recovery and metals extraction from the SSA.


Subject(s)
Conservation of Natural Resources/methods , Iron Compounds , Phosphorus/chemistry , Sewage/chemistry , Waste Disposal, Fluid/methods , Denmark , Incineration , Phosphorus/analysis
16.
Chemosphere ; 117: 124-31, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24997283

ABSTRACT

Some organic contaminants can accumulate in organisms and cause irreversible damages in biological systems through direct or indirect toxic effects. In this study the feasibility of the electrokinetic (EK) process for the remediation of 17ß-oestradiol (E2), 17α-ethinyloestradiol (EE2), bisphenol A (BPA), nonylphenol (NP), octylphenol (OP) and triclosan (TCS) in soils was studied in a stationary laboratory cell. The experiments were conducted using a silty loam soil (S2) at 0, 10 and 20mA and a sandy soil (S3) at 0 and 10 mA. A pH control in the anolyte reservoir (pH>13) at 10 mA was carried out using S2, too. Photo and electrodegradation experiments were also fulfilled. Results showed that EK is a viable method for the remediation of these contaminants, both through mobilization by electroosmotic flow (EOF) and electrodegradation. As EOF is very sensible to soil pH, the control in the anolyte increased EOF rate, consequently enhancing contaminants mobilization towards the cathode end. The extent of the mobilization towards the electrode end was mainly dependent on compounds solubility and octanol-water partition coefficient. In the last 24h of experiments, BPA presented the highest mobilization rate (ca. 4 µg min(-1)) with NP not being detected in the catholyte. At the end of all experiments the percentage of contaminants that remained in the soil ranged between 17 and 50 for S2, and between 27 and 48 for S3, with no statistical differences between treatments. The mass balance performed showed that the amount of contaminant not detected in the cell is similar to the quantity that potentially may suffer photo and electrodegradation.


Subject(s)
Endocrine Disruptors/chemistry , Environmental Pollution/prevention & control , Environmental Restoration and Remediation/methods , Soil Pollutants/chemistry , Electrodes , Kinetics
17.
Sci Total Environ ; 493: 178-84, 2014 Sep 15.
Article in English | MEDLINE | ID: mdl-24946031

ABSTRACT

Molinate is a pesticide widely used, both in space and time, for weed control in rice paddies. Due to its water solubility and affinity to organic matter, it is a contaminant of concern in ground and surface waters, soils and sediments. Previous works have showed that molinate can be removed from soils through electrokinetic (EK) remediation. In this work, molinate degradation by zero valent iron nanoparticles (nZVI) was tested in soils for the first time. Soil is a highly complex matrix, and pollutant partitioning between soil and water and its degradation rates in different matrices is quite challenging. A system combining nZVI and EK was also set up in order to study the nanoparticles and molinate transport, as well as molinate degradation. Results showed that molinate could be degraded by nZVI in soils, even though the process is more time demanding and degradation percentages are lower than in an aqueous solution. This shows the importance of testing contaminant degradation, not only in aqueous solutions, but also in the soil-sorbed fraction. It was also found that soil type was the most significant factor influencing iron and molinate transport. The main advantage of the simultaneous use of both methods is the molinate degradation instead of its accumulation in the catholyte.


Subject(s)
Azepines/chemistry , Environmental Restoration and Remediation/methods , Pesticides/chemistry , Soil Pollutants/chemistry , Thiocarbamates/chemistry , Azepines/analysis , Iron/chemistry , Metal Nanoparticles/chemistry , Pesticides/analysis , Soil/chemistry , Soil Pollutants/analysis , Thiocarbamates/analysis
18.
Acta Cir Bras ; 28(11): 778-82, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24316745

ABSTRACT

PURPOSE: To analyze the viability of using Gelpoint® (single-port access) to make partial and total nephrectomy in pigs and to describe the technical difficulties found during these surgical procedures. METHODS: Ten pigs (Landrace specie) with 20 kg in average were distributed in two groups. Group A: total right nephrectomy and Group B: partial left nephrectomy. The procedures were performed inside the Surgical Technique Room from Pontifícia Universidade Católica do Parana (PUCPR). RESULTS: In Group A, time to single-port insertion varied from one to two minutes and total time of the procedures were 20.4 ± 8.2 minutes. Bleeding was under than 20 mL in 70% of animals. Time of instrument excision was 20.7 ± 12 seconds and time of hilum dissection was 3.9 ± 2.2 minutes. In Group B, after total contralateral nephrectomy two surgical procedures were not concluded due to bleeding. In this group, time of surgery was 6.8 ± 4.2 minutes. With the exception of the second surgery, the highest blood volume loss was 50 mL. The mean excision time was 22.3 ± 22.3 seconds. CONCLUSION: Total and partial nephrectomy through umbilical single-access using GelPoint® was feasible and safe in pigs.


Subject(s)
Laparoscopy/methods , Nephrectomy/methods , Animals , Blood Loss, Surgical , Feasibility Studies , Laparoscopy/instrumentation , Models, Animal , Nephrectomy/instrumentation , Operative Time , Reproducibility of Results , Swine , Time Factors , Umbilicus/surgery
19.
Acta cir. bras ; 28(11): 778-782, Nov. 2013. ilus, tab
Article in English | LILACS | ID: lil-695958

ABSTRACT

PURPOSE: To analyze the viability of using Gelpoint® (single-port access) to make partial and total nephrectomy in pigs and to describe the technical difficulties found during these surgical procedures. METHODS: Ten pigs (Landrace specie) with 20kg in average were distributed in two groups. Group A: total right nephrectomy and Group B: partial left nephrectomy. The procedures were performed inside the Surgical Technique Room from Pontifícia Universidade Católica do Parana (PUCPR). RESULTS: In Group A, time to single-port insertion varied from one to two minutes and total time of the procedures were 20.4±8.2 minutes. Bleeding was under than 20 mL in 70% of animals. Time of instrument excision was 20.7±12 seconds and time of hilum dissection was 3.9±2.2 minutes. In Group B, after total contralateral nephrectomy two surgical procedures were not concluded due to bleeding. In this group, time of surgery was 6.8±4.2 minutes. With the exception of the second surgery, the highest blood volume loss was 50 mL. The mean excision time was 22.3 ± 22.3 seconds. CONCLUSION: Total and partial nephrectomy through umbilical single-access using GelPoint® was feasible and safe in pigs.


Subject(s)
Animals , Laparoscopy/methods , Nephrectomy/methods , Blood Loss, Surgical , Feasibility Studies , Laparoscopy/instrumentation , Models, Animal , Nephrectomy/instrumentation , Operative Time , Reproducibility of Results , Swine , Time Factors , Umbilicus/surgery
20.
J Chromatogr A ; 1178(1-2): 215-22, 2008 Jan 18.
Article in English | MEDLINE | ID: mdl-18070625

ABSTRACT

The volatile composition of 20-year-old out-of-service creosote-treated railway wood sleepers was studied. The emitted volatile fraction was collected by means of dynamic purge-and-trap concentration at ambient temperature, and analyzed by comprehensive two-dimensional gas chromatography (GC x GC) hyphenated with mass spectrometric detection systems, using quadrupole (GC x GC/qMS) and time-of-flight (GC x GC/ToF-MS) mass analyzers and selective nitrogen-phosphorus detection (GC x GC-NPD). The analysis of mass spectrometry data and GC x GC retention time allowed the tentative identification of about 300 compounds based on spectrometric data and positioning of each compound in the GC x GC plot. Major important headspace components are polyaromatic hydrocarbons, phenols and benzene derivatives, hydrocarbons and heterocyclic compounds containing nitrogen, sulphur or oxygen atoms. Many of the reported compounds are listed as belonging to toxicological substance classes which have been related to harmful health effects. GC x GC provides greater speciation and evidence of composition heterogenicity of the sample than one-dimensional GC analysis, thus allowing to better demonstrate its potential toxicity. Data obtained by specific detection systems for N-heterocycles assisted mass data interpretation assignments. The enhanced separation power obtained after GC x GC compared to one-dimensional gas chromatography (1D-GC) together with spectral deconvolution and correlation with physical-chemical data, allowed the identification of complex isomer clusters, as demonstrated for alkylquinolines, and applied also to alkylphenols, alkylbenzenes and alkylnaphthalenes.


Subject(s)
Creosote/analysis , Gas Chromatography-Mass Spectrometry/methods , Wood , Creosote/isolation & purification
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