175 results on '"Bastiaens, L."'
Search Results
52. Field injection of microscale zerovalent iron for groundwater remediation
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Rajandrea Sethi, Tiziana Tosco, Luna, Michela, Gastone, Francesca, Velimirovic, M., Gemoets, J., Muyshond, R., Sapion, H., Klaas, N., and Bastiaens, L.
- Subjects
guar gum/MZVI suspensions ,microscale zero-valent iron ,pilot field injection
53. Evaluation of the intrinsic MTBE biodegradation potential in MTBE-contaminated soils
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Moreels, D., Bastiaens, L., Merckx, R., Ollevier, F., Diels, L., and Dirk Springael
54. The influence of environmental factors on MTBE/TBA degradation by a bacterial consortium: Optimization of an inoculated bioreactor
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Debor, L., Bastiaens, L., Smets, I., Impe, J., and Dirk Springael
55. Kinetics of trichloroethene (TCE) reduction by zero-valent iron: Effect of medium composition
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Dries, J., Bastiaens, L., Springael, D., Diels, L., and Spiros Agathos
56. Pilot Scale Injection of Guar Gum Stabilized Micro-sized Zero-valent iron via Hydro-fracturing
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Velimirovic, M., Uyttebroek, M., Bastiaens, L., Boer, C., Klaas, N., Braun, J., Tiziana Tosco, Luna, Michela, Gastone, Francesca, Rajandrea Sethi, Sapion, H., Eisenmann, H., and Larsson, P. O.
- Subjects
groundwater remediation ,pilot field injection ,hydro-fracturing of porous media ,microscale zero-valent iron ,direct push injection
57. Injection of guar gum micro-sized zero-valent iron via direct push – field study
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Velimirovic, M., Bastiaens, L., Muyshondt, R., Gemoets, J., Sterckx, H., Klaas, N., Gastone, Francesca, Rajandrea Sethi, Sapion, H., and Larsson, P. O.
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aquifer ,remediation ,groundwater ,pollution ,nanoscale zerovalent iron (NZVI)
58. Dynamics of oligotrophic microbial communities in BTEX-contaminated groundwater plumes
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Hendrickx, B., Dejonghe, W., Boënne, W., Bastiaens, L., Springael, D., Lederer, T., Miroslav Cernik, Verstraete, W., Bucheli, M., Rüegg, I., and Egli, Th
59. Effect of humic acids on heavy metal removal by zero-valent iron
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Dries, J., Kemps, A., Trögl, J., Bastiaens, L., Diels, L., and Spiros Agathos
60. Removal of mixed chlorinated ethenes and heavy metals in zero valent iron systems
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Dries, J., Bastiaens, L., Springael, D., Spiros Agathos, and Diels, L.
61. Tailored carrier/bacteria technology for rehabilitation of areas with pesticide-containing pollution – AQUAREHAB WP2
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Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, Universitat Politècnica de Catalunya. SETRI - Grup de Tècniques de Separació i Tractament de Residus Industrials, Ronen, Z., Weisbrod, N., Adar, E., Cohen, M., Amiaz, Y., Hermann, S., Springael, D., Sorensen, S.R., Calderer, M., Martí Gregorio, Vicenç, Bastiaens, L., Universitat Politècnica de Catalunya. Departament d'Enginyeria Química, Universitat Politècnica de Catalunya. SETRI - Grup de Tècniques de Separació i Tractament de Residus Industrials, Ronen, Z., Weisbrod, N., Adar, E., Cohen, M., Amiaz, Y., Hermann, S., Springael, D., Sorensen, S.R., Calderer, M., Martí Gregorio, Vicenç, and Bastiaens, L.
- Abstract
Postprint (published version)
62. Does residential treatment impact pharmacotherapy in children and adolescents?
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Bastiaens L
- Published
- 2004
63. Vormgevend gebruik van klank en dynamiek. De uitvoering van Bachs Johannespassion benaderd als een autonome esthetische verschijning. : Formative use of sound and dynamics. The performance of Bach's St. John Passion considered as an autonomic aesthetic appearance
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Hoek, K, Bastiaens, L, Fidom, H, and Verdin, J
- Abstract
Formative use of sound and dynamics. The performance of bach's In the second half of the 19th century a making of music was developed in Germany in which sounds are related to each other through gradually changing intensity, both in terms of loudness and tempo. In this music-making the melody is not formed on and against a pulse with fixed metrical accents. Music develops rather from attention to sound into motives and then into larger units. After the First World War, clarity, simplicity and objectivity are considered increasingly important. Making music based on transitional dynamics and tempo fluctuations (with the accompanying sound palette) is increasingly considered as subjective and therefore outdated. On this basis, the development of performance practice in the second half of the 20th century is largely based on pulse and meter; this concerns the performance of early music (music from before 1800) as well as music composed after 1800. It is interesting that listening is considered most important in 19th-century music-making: music is formed and exists primarily in the imagination of the listener. My listening - also as a musician - reflects this. It is not so much determined by interest in pulse and meter, but rather by sound differentiation, transitional dynamics and tempo fluctuations. Phenomena and concepts such as pulse, motorial movement, meter and rhythm are for me derivatives of sound handling; not vice versa. I call this: formative use of sound and dynamics. This includes not only music from the 19th century but also from the period before and after, such as music by Varèse and Xenakis. The research, of which my edition of the St. John Passion by J.S. Bach is the result, was initially focused on the question: what impact does this method have on performing music of composers such as Mahler, Sweelinck, Frescobaldi, Bach? To prevent diffusing the research, the St. John Passion has been chosen as a specific research topic during the course of it. The study showed particularly strong interactions between music aesthetics (thinking about conditions under which sounds can be related to each other, leading to an impressive collection of literature on the philosophy of music in the 19th century) and performance practice (practical realization). In the study of the 19th-century philosophy of music in relation to my music-making and verification thereof by making this edition of the St. John Passion, these two areas are distinguished separately but at the same time related. The process of performance is central; this is the way in which the sounding realization of the composition to be performed is made. This process is described with reference to a performance model. The formative use of sound and dynamics is a main subject in this model. status: published
- Published
- 2019
64. Prodromal or Factitious Psychosis: A Cautionary Tale in the Era of Increasing Social Media Use by Vulnerable Individuals.
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Bastiaens L, Cristofano-Casella S, and Bastiaens J
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- Female, Adolescent, Young Adult, Humans, Critical Care, Social Media, Antipsychotic Agents, Borderline Personality Disorder diagnosis, Borderline Personality Disorder therapy, Psychotic Disorders diagnosis, Psychotic Disorders drug therapy
- Abstract
Research on the prodromal phase of schizophrenia has been ongoing for several decades and, more recently, findings from this research are being incorporated into everyday psychiatric practice, such as the use of interviews to evaluate prodromal symptomatology. This evolution is happening in the midst of an explosion of social media use by teenagers and young adults, increasing the exposure of youth to portrayals of psychiatric experiences. For example, reports from around the world of "TIK-TOK tics" emphasize the role of social media in the "creation" of psychiatric symptoms. This case report highlights the importance of a full psychiatric evaluation in acute care settings where quick treatment of psychotic symptoms is the norm. A 15-year-old patient was initially diagnosed with prodromal schizophrenia but, after a more extensive evaluation during a second admission, she was diagnosed with borderline personality disorder. Her antipsychotic treatment regimen was stopped and appropriate education and treatment were started, without the recurrence of "psychotic symptoms" during follow-up. It may be that patients with borderline personality disorder, a frequent condition on inpatient units, are at particular risk of assimilating symptoms as represented on social media., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2024
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65. The Impact of Non-Concentrated Storage on the Centrifugation Yield of Microchloropsis gaditana : A Pilot-Scale Study.
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Verspreet J, Schoeters F, and Bastiaens L
- Abstract
Non-concentrated algae storage can bridge the period between algae harvesting and processing while avoiding the stress conditions associated with the concentration step required for concentrate storage. This study aimed to examine organic matter losses during the non-concentrated storage of Microchloropsis gaditana at pilot-scale. Algae cultures (400-500 L) were stored for up to 12 days either at an 8 °C target temperature or at 19 °C as the average temperature. The centrifugation yield of stored algal cultures decreased from day 5 or day 8 onwards for all storage conditions. After 12 days, the centrifugation yields were between 57% and 93% of the initial yields. Large differences in centrifugation yields were noted between the algae batches. The batch-to-batch difference outweighed the effect of storage temperature, and the highest yield loss was observed for the 8 °C cooled algae batch. The analysis of stored algae before and after centrifugation suggested that the decreasing yields were not related to respiration losses, but rather, the decreasing efficiency with which organic matter is collected during the centrifugation step.
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- 2024
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66. Applications of Microalgae in Foods, Pharma and Feeds and Their Use as Fertilizers and Biostimulants: Legislation and Regulatory Aspects for Consideration.
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Su M, Bastiaens L, Verspreet J, and Hayes M
- Abstract
Microalgae are a rich resource of lipids, proteins, carbohydrates and pigments with nutritional and health benefits. They increasingly find use as ingredients in functional foods and feeds as well as in cosmetics and agricultural products including biostimulants. One of their distinct advantages is their ability to grow on wastewaters and other waste streams, and they are considered an environmentally friendly and cheap method to recover nutrients and remove pollutants from the environment. However, there are limits concerning their applications if grown on certain waste streams. Within, we collate an overview of existing algal applications and current market scenarios for microalgal products as foods and feeds along with relevant legislative requirements concerning their use in Europe and the United States. Microalgal compounds of interest and their extraction and processing methodologies are summarized, and the benefits and caveats of microalgae cultivated in various waste streams and their applications are discussed.
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- 2023
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67. The Impact of Nutrient Limitation and Harvest Method on the Wet Preservation of Chlorella vulgaris Biomass.
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Verspreet J, Kuchendorf CM, Ackermann B, and Bastiaens L
- Abstract
The temporary storage of wet algae concentrates enables the decoupling in time of algae harvests and their biorefinery. However, the impact of cultivation and of the harvest conditions on algae quality during preservation is largely unknown. This study aimed to determine the impact of nutrient limitation and of harvest methods on the preservation of Chlorella vulgaris biomass. Algae were either well-fed until harvest or received no nutrients for one week, and were harvested by either batch or continuous centrifugation. The organic acid formation, lipid levels, and lipolysis were monitored. Nutrient limitation had a large impact and resulted in lower pH values (4.9 ± 0.4), high levels of lactic acid and acetic acid, and a slightly higher degree of lipid hydrolysis. Concentrates of well-fed algae had a higher pH (7.4 ± 0.2) and another pattern of fermentation products with mainly acetic acid, succinic acid, and, to a smaller extent, lactic acid and propionic acid. The effect of the harvest method was smaller, with, most often, higher lactic acid and acetic acid levels for algae harvested by continuous centrifugation than for those obtained by batch centrifugation. In conclusion, nutrient limitation, a well-known method to enhance algae lipid levels, can impact several quality attributes of algae during their wet storage.
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- 2023
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68. The Winchcombe meteorite, a unique and pristine witness from the outer solar system.
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King AJ, Daly L, Rowe J, Joy KH, Greenwood RC, Devillepoix HAR, Suttle MD, Chan QHS, Russell SS, Bates HC, Bryson JFJ, Clay PL, Vida D, Lee MR, O'Brien Á, Hallis LJ, Stephen NR, Tartèse R, Sansom EK, Towner MC, Cupak M, Shober PM, Bland PA, Findlay R, Franchi IA, Verchovsky AB, Abernethy FAJ, Grady MM, Floyd CJ, Van Ginneken M, Bridges J, Hicks LJ, Jones RH, Mitchell JT, Genge MJ, Jenkins L, Martin PE, Sephton MA, Watson JS, Salge T, Shirley KA, Curtis RJ, Warren TJ, Bowles NE, Stuart FM, Di Nicola L, Györe D, Boyce AJ, Shaw KMM, Elliott T, Steele RCJ, Povinec P, Laubenstein M, Sanderson D, Cresswell A, Jull AJT, Sýkora I, Sridhar S, Harrison RJ, Willcocks FM, Harrison CS, Hallatt D, Wozniakiewicz PJ, Burchell MJ, Alesbrook LS, Dignam A, Almeida NV, Smith CL, Clark B, Humphreys-Williams ER, Schofield PF, Cornwell LT, Spathis V, Morgan GH, Perkins MJ, Kacerek R, Campbell-Burns P, Colas F, Zanda B, Vernazza P, Bouley S, Jeanne S, Hankey M, Collins GS, Young JS, Shaw C, Horak J, Jones D, James N, Bosley S, Shuttleworth A, Dickinson P, McMullan I, Robson D, Smedley ARD, Stanley B, Bassom R, McIntyre M, Suttle AA, Fleet R, Bastiaens L, Ihász MB, McMullan S, Boazman SJ, Dickeson ZI, Grindrod PM, Pickersgill AE, Weir CJ, Suttle FM, Farrelly S, Spencer I, Naqvi S, Mayne B, Skilton D, Kirk D, Mounsey A, Mounsey SE, Mounsey S, Godfrey P, Bond L, Bond V, Wilcock C, Wilcock H, and Wilcock R
- Abstract
Direct links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth's water.
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- 2022
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69. Nutritional Profiling and Preliminary Bioactivity Screening of Five Micro-Algae Strains Cultivated in Northwest Europe.
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Verspreet J, Soetemans L, Gargan C, Hayes M, and Bastiaens L
- Abstract
This study aimed to map the nutritional profile and bioactivities of five microalgae that can be grown in Northwest Europe or areas with similar cultivation conditions. Next to the biochemical composition, the in vitro digestibility of carbohydrates, proteins, and lipids was studied for Chlamydomonas nivalis , Porphyridium purpureum , Chlorella vulgaris , Nannochloropsis gaditana , and Scenedesmus species biomass. These microalgae were also assessed for their ability to inhibit the angiotensin-1-converting enzyme (ACE-1, EC 3.4.15.1), which is known to play a role in the control of blood pressure in mammals. Large differences in organic matter solubility after digestion suggested that a cell disruption step is needed to unlock the majority of the nutrients from N. gaditana and Scenedesmus species biomass. Significant amounts of free glucose (16.4-25.5 g glucose/100 g dry algae) were detected after the digestion of C. nivalis , P. purpureum , and disrupted Scenedesmus . The fatty acid profiles showed major variations, with particularly high Ω-3 fatty acid levels found in N. gaditana (5.5 ± 0.5 g/100 g dry algae), while lipid digestibility ranged from 33.3 ± 6.5% (disrupted N. gaditana ) to 67.1 ± 11.2% ( P. purpureum ). C. vulgaris and disrupted N. gaditana had the highest protein content (45-46% of dry matter), a nitrogen solubility after digestion of 65-71%, and the degree of protein hydrolysis was determined as 31% and 26%, respectively. Microalgae inhibited ACE-1 by 73.4-87.1% at physiologically relevant concentrations compared to a commercial control. These data can assist algae growers and processors in selecting the most suitable algae species for food or feed applications.
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- 2021
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70. Characteristics of chitin extracted from black soldier fly in different life stages.
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Soetemans L, Uyttebroek M, and Bastiaens L
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- Animals, Chitin isolation & purification, Chitin ultrastructure, Decapodiformes chemistry, Larva chemistry, Pupa chemistry, Spectroscopy, Fourier Transform Infrared, Chitin chemistry, Chitosan chemistry, Diptera chemistry
- Abstract
Chitin was collected and extracted along different lifecycle stages of the Black Soldier Fly (BSF) (larvae, prepupae, pupae, flies, shedding & cocoons). The chitin content in the collected biomass ranged between 8% and 24%, with sheddings and cocoons being most rich in chitin. Purified chitin was subjected to a physicochemical evaluation based on FTIR, XRD, and TGA as well as a deacetylation step. The data indicated that BSF chitin was α-chitin with FTIR profiles matching closely to shrimp chitin and showing some differences compared to squid pen chitin (β-chitin). Small physicochemical differences were observed among the different BSF samples. Prepupae and cocoon chitin was more crystalline while chitin from larvae and sheddings had a lower thermal degradation temperature. In addition, sheddings were more difficult to purify. Further processing to chitosan showed that a deacetylation degree of 89% could be obtained for all samples after 3 h, although sheddings were found to be less reactive in the deacetylation process. Overall, the small differences in physicochemical properties that were detected between the BSF chitin samples did not prevent further processing of chitin to chitosan with the same degree of deacetylation via the same treatment., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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71. Degree of Hydrolysis Affects the Techno-Functional Properties of Lesser Mealworm Protein Hydrolysates.
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Leni G, Soetemans L, Caligiani A, Sforza S, and Bastiaens L
- Abstract
Protein hydrolysates from lesser mealworm ( Alphitobius diaperinus , LM) were obtained by enzymatic hydrolysis with protease from Bacillus licheniformis . A preliminary test performed for five hours of hydrolysis generated an insect protein hydrolysate with 15% of degree of hydrolysis (DH), optimum solubility property and oil holding capacity, but emulsifying and foaming ability were completely impaired. In order to investigate the potential implication of DH on techno-functional properties, a set of protein hydrolysates with a different DH was obtained by sub-sampling at different time points during three hours of enzymatic hydrolysis process. An increase in DH% had positive effects on the solubility property and oil holding ability, while a reduced emulsifying ability was observed up to five hours of hydrolysis. These results demonstrated that the enzymatic hydrolysis, if performed under controlled conditions and not for a long period, represents a valid method to extract high quality protein from insects with tailored techno-functionality, in order to produce tailored ingredients for feed and food purpose.
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- 2020
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72. Agri-Food Side-Stream Inclusion in The Diet of Alphitobius Diaperinus . Part 2: Impact on Larvae Composition.
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Soetemans L, Gianotten N, and Bastiaens L
- Abstract
Insects are gaining interest as an alternative protein source for feed/food purposes. Although the lesser mealworm (LM) is commercially produced for human consumption, published data on its nutrient composition is scarce. This study reports on LM larvae reared on 18 different diets composed of side-streams to (1) determine the nutritional composition of the larvae and (2) study the effect of dietary changes on the larval nutrient composition. The LM larvae proved to be of good nutritional value with essential amino acids profiles comparable with that of beef and linoleic acid (C18:2) was the most dominant essential fatty acids in the larvae. The side-stream based diets varied on dry matter basis in protein (16-34%) and lipid content (2-19%). The nutrient content of the larvae reared on diets that supported good growth ranged between 37% and 49% of protein, 22% and 26% of lipid and 4% to 6% of chitin on dry matter basis. No significant correlations were identified between the larval protein or lipid content and that of the diet, but it was found between the diet nutrients and larval growth. Based on larval growth data and economic considerations, diets composed of wheat middlings with a 10-15% inclusion of rapeseed meal were identified as suitable feed for LM. Highest larval yields were obtained with diets containing 15-22% of proteins and 5-10% of lipids.
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- 2020
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73. Simplified determination of the content and average degree of acetylation of chitin in crude black soldier fly larvae samples.
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D'Hondt E, Soetemans L, Bastiaens L, Maesen M, Jespers V, Van den Bosch B, Voorspoels S, and Elst K
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- Acetylation, Animals, Chromatography, Liquid, Larva, Chitin chemistry, Chitin isolation & purification, Simuliidae chemistry
- Abstract
Insects are considered a promising alternative protein source for food and feed, but contain significant amounts of chitin, often undesirable due to indigestibility, disagreeable texture and negative effect on nutrients intake. Fractionation strategies are thus increasingly being applied to isolate and valorize chitin separately. The analysis of chitin generally requires an intensive pretreatment to remove impurities, and derivatization to generate sufficient detector response. In this work, a liquid chromatography method, without pretreatment nor derivatization, was developed for the simultaneous determination of chitin content and degree of acetylation in non-purified samples of black soldier fly (BSF) larvae. The method is found to be more suitable, compared to traditional methods, for assessing high degrees of acetylation. For the first time, the degree of acetylation of BSF chitin (81 ± 2%) is reported. Additionally, the chitin content of BSF soft tissues is estimated at approximately 20% of the total chitin content (8.5 ± 0.1%)., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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74. Agri-Food Side-Stream Inclusions in the Diet of Alphitobius diaperinus Part 1: Impact on Larvae Growth Performance Parameters.
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Gianotten N, Soetemans L, and Bastiaens L
- Abstract
Insects are attracting increased attention in western countries as a protein source for feed and food industries. Currently, insect farmers use high-quality (cereal-based) diets. Part of the ingredients in these diets can also be used directly in food applications. To avoid competition and improve the sustainable and economical aspect of insect rearing, a search for alternative insect diets is ongoing. Side-streams from the agri-food sector offer potential. The lesser mealworm ( Alphitobius diaperinus ) is an insect that is commercially reared on large scale for food application. The current paper reports on six agri-food side-streams that were included in the diet of the lesser mealworm. The impact of 29 diets (single side-streams or mixtures) on the larvae growth was evaluated by monitoring the larval yield, efficiency of conversion of ingested feed, and larval weight. The larvae were able to grow on all diets, but differences in growth were observed. Two side-streams, wheat middlings and rapeseed meal, were proven to support good larval performance when used as a single ingredient. A combination of these two with brewery grains as moisture source provided (1) the best larval growth and (2) the most economically profitable diet. In conclusion, this study illustrates successful rearing of the lesser mealworm on side-stream-based diets., Competing Interests: The authors declare no conflict of interest.
- Published
- 2020
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75. Treatment of Adult ADHD without Stimulants: Effectiveness in A Dually Diagnosed Correctional Population.
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Bastiaens L, Scott O, and Galus J
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- Adult, Attention Deficit Disorder with Hyperactivity epidemiology, Comorbidity, Diagnosis, Dual (Psychiatry), Female, Follow-Up Studies, Humans, Male, Retrospective Studies, Severity of Illness Index, Adrenergic Agents pharmacology, Atomoxetine Hydrochloride pharmacology, Attention Deficit Disorder with Hyperactivity drug therapy, Guanfacine pharmacology, Mental Disorders epidemiology, Nortriptyline pharmacology, Outcome Assessment, Health Care, Prisoners, Substance-Related Disorders epidemiology
- Abstract
Adult ADHD has received increased attention in the past two decades. There is a complex relationship between ADHD and substance use disorders, with ADHD being a risk factor for and a moderator in the treatment of addiction. ADHD is also a risk factor for the development of antisocial personality disorder. As a result, ADHD is prevalent in a correctional dually diagnosed population. This retrospective chart review reports on the effectiveness of the treatment for ADHD in a population with substance use disorders, residing in a correctional community center for treatment and reintegration purposes. Only patients with a primary diagnosis of ADHD were included and only nonstimulants were used. After an average of four visits, or approximately four months, patient showed a moderate response with a pretreatment to posttreatment effect size of 1.4. Sixty-four percent of patients responded and 35% remitted, according to the Clinical Global Index Severity Scale as the primary outcome measure. While stimulants are considered the first-line treatment for ADHD, they clearly present challenges in certain populations, especially in patients with significant antisocial and addiction histories. It does appear that non-stimulants are effective in this population. It is speculated that the response and remission rate could be improved by adding ADHD specific psychosocial interventions.
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- 2019
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76. Supercritical CO₂ Extraction of Nannochloropsis sp.: A Lipidomic Study on the Influence of Pretreatment on Yield and Composition.
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Elst K, Maesen M, Jacobs G, Bastiaens L, Voorspoels S, and Servaes K
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- Biomass, Chloroform chemistry, Chromatography, High Pressure Liquid, Chromatography, Supercritical Fluid, Fatty Acids analysis, Hydrolysis, Mass Spectrometry, Methanol chemistry, Phosphatidylcholines analysis, Carbon Dioxide chemistry, Complex Mixtures chemistry, Glycolipids analysis, Phospholipids analysis, Solvents chemistry, Stramenopiles chemistry
- Abstract
Algal lipids have gained wide interest in various applications ranging from biofuels to nutraceuticals. Given their complex nature composed of different lipid classes, a deep knowledge between extraction conditions and lipid characteristics is essential. In this paper, we investigated the influence of different pretreatments on lipid extraction with supercritical CO₂ by a lipidomic approach. Pretreatment was found to double the total extraction yield, thereby reaching 23.1 wt.% comparable to the 26.9 wt.% obtained with chloroform/methanol. An increase in acylglycerides was concurrently observed, together with a nearly doubling of free fatty acids indicative of partial hydrolysis. Moreover, an alteration in the distribution of glyco- and phospholipids was noted, especially promoting digalactosyldiglycerides and phosphatidylcholine as compared to monogalactosyldiglycerides and phosphatidylglycerol. At optimized conditions, supercritical CO₂ extraction provided a lipid extract richer in neutral lipids and poorer in phospholipids as compared to chloroform/methanol, though with a very similar fatty acid distribution within each lipid class.
- Published
- 2018
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77. Comparison of the Adult ADHD Self Report Scale Screener for DSM-IV and DSM-5 in a Dually Diagnosed Correctional Population.
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Bastiaens L and Galus J
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- Female, Humans, Male, Attention Deficit Disorder with Hyperactivity diagnosis, Attention Deficit Disorder with Hyperactivity psychology, Diagnostic and Statistical Manual of Mental Disorders, Mass Screening, Self Report
- Abstract
The diagnosis of Attention Deficit Hyperactivity Disorder in adults with Substance Use Disorders is complicated. A specific screening tool, such as the World Health Organization Adult ADHD Self Report Scale Screener can be the first step in identifying the condition. Recently, the screener has been revised because the Diagnostic and Statistical Manual of Mental Disorders, Fifth edition, made some changes to the criteria for Attention Deficit Hyperactivity Disorder. This study compared the screeners based upon the Fourth and Fifth edition of the Manual. One hundred and forty patients, including seventy with Attention Deficit Hyperactivity Disorder, completed both screeners, independent from a clinical diagnostic interview. The sensitivity, specificity, and predictive values were calculated based on four different scoring methods: a categorical score of three or four positive answers, and a dimensional score of twelve or fourteen. Both screening instruments appeared to perform equally without significant differences between them, no matter which scoring system was used. However, the only satisfactory result was obtained using the dimensional scoring with a cutoff of 12, providing a sensitivity and negative predictive value above 80%. This is a lower cut off than recommended in community and clinic samples. It is possible that the cut off of the screener may need to be adjusted depending on the circumstances within which it is used.
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- 2018
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78. The DSM-5 Self-Rated Level 1 Cross-Cutting Symptom Measure as a Screening Tool.
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Bastiaens L and Galus J
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- Adult, Female, Humans, Male, Middle Aged, Sensitivity and Specificity, Anxiety diagnosis, Anxiety Disorders diagnosis, Bipolar Disorder diagnosis, Depression diagnosis, Depressive Disorder diagnosis, Diagnostic and Statistical Manual of Mental Disorders, Psychiatric Status Rating Scales standards, Psychotic Disorders diagnosis
- Abstract
The DSM-5 Self-Rated Level 1 Cross-Cutting Symptom Measure was developed to aid clinicians with a dimensional assessment of psychopathology; however, this measure resembles a screening tool for several symptomatic domains. The objective of the current study was to examine the basic parameters of sensitivity, specificity, positive and negative predictive power of the measure as a screening tool. One hundred and fifty patients in a correctional community center filled out the measure prior to a psychiatric evaluation, including the Mini International Neuropsychiatric Interview screen. The above parameters were calculated for the domains of depression, mania, anxiety, and psychosis. The results showed that the sensitivity and positive predictive power of the studied domains was poor because of a high rate of false positive answers on the measure. However, when the lowest threshold on the Cross-Cutting Symptom Measure was used, the sensitivity of the anxiety and psychosis domains and the negative predictive values for mania, anxiety and psychosis were good. In conclusion, while it is foreseeable that some clinicians may use the DSM-5 Self-Rated Level 1 Cross-Cutting Symptom Measure as a screening tool, it should not be relied on to identify positive findings. It functioned well in the negative prediction of mania, anxiety and psychosis symptoms.
- Published
- 2018
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79. Contrasting dual (C, Cl) isotope fractionation offers potential to distinguish reductive chloroethene transformation from breakdown by permanganate.
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Doğan-Subaşı E, Elsner M, Qiu S, Cretnik S, Atashgahi S, Shouakar-Stash O, Boon N, Dejonghe W, and Bastiaens L
- Abstract
cis-1,2-Dichloroethene (cis-DCE) and trichloroethene (TCE) are persistent, toxic and mobile pollutants in groundwater systems. They are both conducive to reductive dehalogenation and to oxidation by permanganate. In this study, the potential of dual element (C, Cl) compound specific isotope analyses (CSIA) for distinguishing between chemical oxidation and anaerobic reductive dechlorination of cis-DCE and TCE was investigated. Well-controlled cis-DCE degradation batch tests gave similar carbon isotope enrichment factors ε
C (‰), but starkly contrasting dual element isotope slopes Δδ13 C/Δδ37 Cl for permanganate oxidation (εC =-26‰±6‰, Δδ13 C/Δδ37 Cl≈-125±47) compared to reductive dechlorination (εC =-18‰±4‰, Δδ13 C/Δδ37 Cl≈4.5±3.4). The difference can be tracked down to distinctly different chlorine isotope fractionation: an inverse isotope effect during chemical oxidation (εCl =+0.2‰±0.1‰) compared to a large normal isotope effect in reductive dechlorination (εCl =-3.3‰±0.9‰) (p≪0.05). A similar trend was observed for TCE. The dual isotope approach was evaluated in the field before and up to 443days after a pilot scale permanganate injection in the subsurface. Our study indicates, for the first time, the potential of the dual element isotope approach for distinguishing cis-DCE (and TCE) concentration drops caused by dilution, oxidation by permanganate and reductive dechlorination both at laboratory and field scale., (Copyright © 2017. Published by Elsevier B.V.)- Published
- 2017
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80. Abuse of Gabapentin is Associated with Opioid Addiction.
- Author
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Bastiaens L, Galus J, and Mazur C
- Subjects
- Adult, Comorbidity, Criminals statistics & numerical data, Diagnosis, Dual (Psychiatry), Female, Gabapentin, Humans, Male, Mental Disorders epidemiology, Middle Aged, Prescription Drug Misuse statistics & numerical data, Surveys and Questionnaires, United States epidemiology, Amines, Attention Deficit Disorder with Hyperactivity epidemiology, Cyclohexanecarboxylic Acids, Depressive Disorder epidemiology, Opioid-Related Disorders epidemiology, Substance-Related Disorders epidemiology, gamma-Aminobutyric Acid
- Abstract
The objective of this study was to evaluate the extent of gabapentin misuse in a dually diagnosed correctional population, and to evaluate if this abuse is specific to the presence of an opioid use disorder (OUD). Two-hundred and fifty former inmates, living in a correctional community center, who were referred for a psychiatric evaluation, were asked, through a brief written questionnaire, whether or not they used the following drugs for non-medical use in the past: opiates, gabapentin, buproprion, quetiapine, and fluoxetine. The average age of this population was 37.2 ± 12.1 years (n = 250). Sixty-four percent were male, 72 % were white, 27 % were black, and 1 % was Hispanic. All patients had substance use disorders, the large majority (72 %) to more than one substance. Fifty-eight percent had an opioid use disorder, again mostly in combination with other drugs and/or alcohol. Depressive disorders and attention deficit hyperactivity disorder were the most common psychiatric conditions. Sixty-two percent of patients reported prescription drug misuse of any kind. As expected, a high percent (55 %) reported opiate misuse. No patient reported fluoxetine misuse. Sixteen percent reported having misused gabapentin in the past. Of patients with an opioid use disorder (OUD: n = 145), 26 % endorsed gabapentin abuse while only 4 % of patients without an OUD (n = 105) endorsed the non-medical use of gabapentin. This difference was highly statistically significant (Chi square χ
2 = 21.6, p < 0.0001). A growing concern about gabapentin misuse was supported in this study: 26 percent of opiate addicted patients reported illegally obtaining, overusing, or malingering problems to obtain gabapentin. This study highlights the fact that gabapentin abuse appears specific to an opioid addicted population.- Published
- 2016
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81. Microbial and mineral evolution in zero valent iron-based permeable reactive barriers during long-term operations.
- Author
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Kumar N, Millot R, Battaglia-Brunet F, Omoregie E, Chaurand P, Borschneck D, Bastiaens L, and Rose J
- Subjects
- Carbon, Environmental Microbiology, Ferric Compounds, Ferrosoferric Oxide, Ferrous Compounds, RNA, Ribosomal, 16S, Sulfates chemistry, X-Ray Diffraction, Groundwater, Iron chemistry, Minerals, Water Purification methods
- Abstract
Impacts of subsurface biogeochemical processes over time have always been a concern for the long-term performance of zero valent iron (Fe(0))-based permeable reactive barriers (PRBs). To evaluate the biogeochemical impacts, laboratory experiments were performed using flow-through glass columns for 210 days at controlled temperature (20 °C). Two different particle sizes of Fe(0) were used in the columns, and to simulate indigenous microbial activity, extra carbon source was provided in the two columns (biotic columns) and the remaining two columns were kept abiotic using gamma radiations. Heavy metals (Zn, As) were removed efficiently in all the columns, and no exhaustion of treatment capability or clogging was observed during our experimental duration. Newly formed Fe mineral phases and precipitates were characterized using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and micro-XRF techniques in solid phase at the end of the experiment. In addition, 16S rRNA gene extraction was used for microbial community identification in biotic columns. During the incubation, microbial population shifted in favor of Desulfosporosinus species (sulfate-reducing bacteria) from initial dominance of Acidithiobacillus ferrooxidans in sediments. Dominant mineral phases detected in biotic columns were mackinawite (FeS) and sulfate green rust, while in abiotic columns, magnetite/maghemite phases were more prevalent.
- Published
- 2016
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82. Use of CAH-degrading bacteria as test-organisms for evaluating the impact of fine zerovalent iron particles on the anaerobic subsurface environment.
- Author
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Velimirovic M, Simons Q, and Bastiaens L
- Subjects
- Anaerobiosis, Bacteria, Biodegradation, Environmental, Corrosion, Environment, Groundwater chemistry, Halogenation, Hydrocarbons analysis, Water Pollutants, Chemical analysis, Environmental Restoration and Remediation methods, Hydrocarbons metabolism, Iron chemistry, Water Pollutants, Chemical metabolism
- Abstract
The release of fine zerovalent iron (ZVI) particles in the environment after being introduced for in-situ treatment of compounds like chlorinated aliphatic hydrocarbons (CAHs) may raise questions toward environmental safety, especially for nanoscale materials. Classical single-species ecotoxicity tests do focus on aerobic conditions and are only relevant for the scenario when ZVI-particles reach surface water. Herein, we present an alternative approach where a CAH-degrading mixed bacterial culture was used as test-organisms relevant for the anaerobic subsurface. The impact of different ZVI particles on the bacterial culture was evaluated mainly by quantifying ATP, a reporter molecule giving a general indication of the microbial activity. These lab-scale batch tests were performed in liquid medium, without protecting and buffering aquifer material, as such representing worst-case scenario. The activity of the bacterial culture was negatively influenced by nanoscale zerovalent iron at doses as low as 0.05 g L(-1). On the other hand, concentrations up to 2 g L(-1) of several different types of microscale zerovalent iron (mZVI) particles stimulated the activity. However, very high doses of 15-30 g L(-1) of mZVI showed an inhibiting effect on the bacterial community. Negative effects of ZVIs were confirmed by H2 accumulation in the batch reactors and the absence of lactate consumption. Observed inhibition also corresponded to a pH increase above 7.5, explicable by ZVI corrosion that was found to be dose-dependent. The obtained results suggest that low doses of mZVIs will not show severe inhibition effects on the microbial community once used for in-situ treatment of CAHs., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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83. Biodegradation: Updating the concepts of control for microbial cleanup in contaminated aquifers.
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Meckenstock RU, Elsner M, Griebler C, Lueders T, Stumpp C, Aamand J, Agathos SN, Albrechtsen HJ, Bastiaens L, Bjerg PL, Boon N, Dejonghe W, Huang WE, Schmidt SI, Smolders E, Sørensen SR, Springael D, and van Breukelen BM
- Subjects
- Biodegradation, Environmental, Electrons, Oxidation-Reduction, Bacteria metabolism, Groundwater microbiology, Water Pollutants, Chemical analysis
- Abstract
Biodegradation is one of the most favored and sustainable means of removing organic pollutants from contaminated aquifers but the major steering factors are still surprisingly poorly understood. Growing evidence questions some of the established concepts for control of biodegradation. Here, we critically discuss classical concepts such as the thermodynamic redox zonation, or the use of steady state transport scenarios for assessing biodegradation rates. Furthermore, we discuss if the absence of specific degrader populations can explain poor biodegradation. We propose updated perspectives on the controls of biodegradation in contaminant plumes. These include the plume fringe concept, transport limitations, and transient conditions as currently underestimated processes affecting biodegradation.
- Published
- 2015
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84. The 12 item W.H.O.D.A.S. as primary self report outcome measure in a correctional community treatment center for dually diagnosed patients.
- Author
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Bastiaens L, Galus J, and Goodlin M
- Subjects
- Adult, Community Mental Health Centers, Criminals, Diagnosis, Dual (Psychiatry), Disability Evaluation, Female, Follow-Up Studies, Humans, Male, Middle Aged, Self Report, Severity of Illness Index, Outcome Assessment, Health Care methods, Psychiatric Status Rating Scales standards, Substance-Related Disorders therapy
- Abstract
The World Health Organization Disability Assessment Scale (WHODAS) is suggested as a measure of impairment in DSM-5. The measurement of impaired functioning is crucial in the rehabilitation of dually diagnosed, addiction and mental health, patients. This study is the first to look at the use of the 12 item self report WHODAS as the primary outcome in a community correctional treatment facility for dually diagnosed patients.100 (55 male; 73 white, 25 black, 2 hispanic) former inmates, age 36.1 ± 11.1, with psychiatric and addiction diagnoses were treated in an integrated program. The 12 item WHODAS was completed by the patients during the initial evaluation and repeated an average of 11.1 ± 2.7 weeks later. The Clinical Global Impression-Severity Scale (CGI) was completed at the same time by the psychiatrist, independently of the WHODAS. At initial assessment, the CGI showed moderate severity and the WHODAS showed severe disability. CGI and WHODAS were significantly correlated (R 0.48, p < 0.0001). After three months of treatment, both measures improved: CGI with 46% and WHODAS with 49%. The CGI showed mild severity and the WHODAS moderate disability. The change in CGI was correlated with the change in WHODAS (R 0.57, p < 0.0001). The WHODAS appears sensitive to clinical improvement related to shortterm treatment of a highly co-morbid dual diagnosis population.
- Published
- 2015
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85. Monitoring the injection of microscale zerovalent iron particles for groundwater remediation by means of complex electrical conductivity imaging.
- Author
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Flores Orozco A, Velimirovic M, Tosco T, Kemna A, Sapion H, Klaas N, Sethi R, and Bastiaens L
- Subjects
- Belgium, Hydrocarbons, Chlorinated analysis, Solutions, Electric Conductivity, Environmental Restoration and Remediation, Groundwater chemistry, Imaging, Three-Dimensional, Iron chemistry
- Abstract
The injection of microscale zerovalent iron (mZVI) particles for groundwater remediation has received much interest in recent years. However, to date, monitoring of mZVI particle injection is based on chemical analysis of groundwater and soil samples and thus might be limited in its spatiotemporal resolution. To overcome this deficiency, in this study, we investigate the application of complex electrical conductivity imaging, a geophysical method, to monitor the high-pressure injection of mZVI in a field-scale application. The resulting electrical images revealed an increase in the induced electrical polarization (∼20%), upon delivery of ZVI into the targeted area, due to the accumulation of metallic surfaces at which the polarization takes place. Furthermore, larger changes (>50%) occurred in shallow sediments, a few meters away from the injection, suggesting the migration of particles through preferential flowpaths. Correlation of the electrical response and geochemical data, in particular the analysis of recovered cores from drilling after the injection, confirmed the migration of particles (and stabilizing solution) to shallow areas through fractures formed during the injection. Hence, our results demonstrate the suitability of the complex conductivity imaging method to monitor the transport of mZVI during subsurface amendment in quasi real-time.
- Published
- 2015
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86. Highly parameterized inversion of groundwater reactive transport for a complex field site.
- Author
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Carniato L, Schoups G, van de Giesen N, Seuntjens P, Bastiaens L, and Sapion H
- Subjects
- Belgium, Hydrology, Rain, Soil chemistry, Water Pollutants, Chemical chemistry, Groundwater chemistry, Models, Theoretical, Volatile Organic Compounds chemistry, Water Movements
- Abstract
In this study a numerical groundwater reactive transport model of a shallow groundwater aquifer contaminated with volatile organic compounds is developed. In addition to advective-dispersive transport, the model includes contaminant release from source areas, natural attenuation, abiotic degradation by a permeable reactive barrier at the site, and dilution by infiltrating rain. Aquifer heterogeneity is parameterized using pilot points for hydraulic conductivity, specific yield and groundwater recharge. A methodology is developed and applied to estimate the large number of parameters from the limited data at the field site (groundwater levels, groundwater concentrations of multiple chemical species, point-scale measurements of soil hydraulic conductivity, and lab-scale derived information on chemical and biochemical reactions). The proposed methodology relies on pilot point parameterization of hydraulic parameters and groundwater recharge, a regularization procedure to reconcile the large number of spatially distributed model parameters with the limited field data, a step-wise approach for integrating the different data sets into the model, and high performance computing. The methodology was proven to be effective in reproducing multiple contaminant plumes and in reducing the prior parameter uncertainty of hydraulic conductivity and groundwater recharge. Our results further indicate that contaminant transport predictions are strongly affected by the choice of the groundwater recharge model and flow parameters should be identified using both head and concentration measurements., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2015
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87. Field assessment of guar gum stabilized microscale zerovalent iron particles for in-situ remediation of 1,1,1-trichloroethane.
- Author
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Velimirovic M, Tosco T, Uyttebroek M, Luna M, Gastone F, De Boer C, Klaas N, Sapion H, Eisenmann H, Larsson PO, Braun J, Sethi R, and Bastiaens L
- Subjects
- Belgium, Groundwater, Pilot Projects, Porosity, Environmental Restoration and Remediation methods, Galactans chemistry, Iron chemistry, Mannans chemistry, Plant Gums chemistry, Trichloroethanes chemistry, Water Pollutants, Chemical chemistry
- Abstract
A pilot injection test with guar gum stabilized microscale zerovalent iron (mZVI) particles was performed at test site V (Belgium) where different chlorinated aliphatic hydrocarbons (CAHs) were present as pollutants in the subsurface. One hundred kilograms of 56μm-diameter mZVI (~70gL(-1)) was suspended in 1.5m(3) of guar gum (~7gL(-1)) solution and injected into the test area. In order to deliver the guar gum stabilized mZVI slurry, one direct push bottom-up injection (Geoprobe) was performed with injections at 5 depths between 10.5 and 8.5m bgs. The direct push technique was preferred above others (e.g. injection at low flow rate via screened wells) because of the limited hydraulic conductivity of the aquifer, and to the large size of the mZVI particles. A final heterogeneous distribution of the mZVI in the porous medium was observed explicable by preferential flow paths created during the high pressure injection. The maximum observed delivery distance was 2.5m. A significant decrease in 1,1,1-TCA concentrations was observed in close vicinity of spots where the highest concentration of mZVI was observed. Carbon stable isotope analysis (CSIA) yielded information on the success of the abiotic degradation of 1,1,1-TCA and indicated a heterogeneous spatio-temporal pattern of degradation. Finally, the obtained results show that mZVI slurries stabilized by guar gum can be prepared at pilot scale and directly injected into low permeable aquifers, indicating a significant removal of 1,1,1-TCA., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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88. Quantitative and functional dynamics of Dehalococcoides spp. and its tceA and vcrA genes under TCE exposure.
- Author
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Doğan-Subaşi E, Bastiaens L, Leys N, Boon N, and Dejonghe W
- Subjects
- Adenosine Triphosphate metabolism, Biodegradation, Environmental drug effects, Ethylenes metabolism, Gene Expression Regulation, Bacterial drug effects, Halogenation, Methane metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, RNA, Ribosomal, 16S genetics, Chloroflexi drug effects, Chloroflexi genetics, Genes, Bacterial drug effects, Trichloroethylene pharmacology
- Abstract
This study aimed at monitoring the dynamics of phylogenetic and catabolic genes of a dechlorinating enrichment culture before, during, and after complete dechlorination of chlorinated compounds. More specifically, the effect of 40 μM trichloroethene (TCE) and 5.6 mM lactate on the gene abundance and activity of an enrichment culture was investigated for 40 days. Although tceA and vcrA gene copy numbers were relatively stable in DNA extracts over time, tceA and vcrA mRNA abundances were upregulated from undetectable levels to 2.96 × and 6.33 × 10⁴ transcripts/mL, respectively, only after exposure to TCE and lactate. While tceA gene transcripts decreased over time with TCE dechlorination, the vcrA gene was expressed steadily even when the concentration of vinyl chloride was at undetectable levels. In addition, ratios between catabolic and phylogenetic genes indicated that tceA and vcrA gene carrying organisms dechlorinated TCE and its produced daughter products, while vcrA gene was mainly responsible for the dechlorination of the lower VC concentrations in a later stage of degradation.
- Published
- 2014
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89. Corrosion rate estimations of microscale zerovalent iron particles via direct hydrogen production measurements.
- Author
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Velimirovic M, Carniato L, Simons Q, Schoups G, Seuntjens P, and Bastiaens L
- Subjects
- Corrosion, Groundwater chemistry, Hydrogen chemistry, Iron chemistry, Metal Nanoparticles chemistry
- Abstract
In this study, the aging behavior of microscale zerovalent iron (mZVI) particles was investigated by quantifying the hydrogen gas generated by anaerobic mZVI corrosion in batch degradation experiments. Granular iron and nanoscale zerovalent iron (nZVI) particles were included in this study as controls. Firstly, experiments in liquid medium (without aquifer material) were performed and revealed that mZVI particles have approximately a 10-30 times lower corrosion rate than nZVI particles. A good correlation was found between surface area normalized corrosion rate (RSA) and reaction rate constants (kSA) of PCE, TCE, cDCE and 1,1,1-TCA. Generally, particles with higher degradation rates also have faster corrosion rates, but exceptions do exists. In a second phase, the hydrogen evolution was also monitored during batch tests in the presence of aquifer material and real groundwater. A 4-9 times higher corrosion rate of mZVI particles was observed under the natural environment in comparison with the aquifer free artificial condition, which can be attributed to the low pH of the aquifer and its buffer capacity. A corrosion model was calibrated on the batch experiments to take into account the inhibitory effects of the corrosion products (dissolved iron, hydrogen and OH(-)) on the iron corrosion rate., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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90. Inhibition of sulfate reducing bacteria in aquifer sediment by iron nanoparticles.
- Author
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Kumar N, Omoregie EO, Rose J, Masion A, Lloyd JR, Diels L, and Bastiaens L
- Subjects
- Acidithiobacillus genetics, Base Sequence, Belgium, Cluster Analysis, DNA Primers genetics, Iron chemistry, Iron metabolism, Molecular Sequence Data, Oxidation-Reduction, Peptococcaceae genetics, Phylogeny, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, X-Ray Diffraction, Acidithiobacillus metabolism, Geologic Sediments microbiology, Groundwater microbiology, Metal Nanoparticles chemistry, Peptococcaceae metabolism, Sulfates metabolism, Water Purification methods
- Abstract
Batch microcosms were setup to determine the impact of different sized zero valent iron (Fe(0)) particles on microbial sulfate reduction during the in situ bio-precipitation of metals. The microcosms were constructed with aquifer sediment and groundwater from a low pH (3.1), heavy-metal contaminated aquifer. Nano (nFe(0)), micro (mFe(0)) and granular (gFe(0)) sized Fe(0) particles were added to separate microcosms. Additionally, selected microcosms were also amended with glycerol as a C-source for sulfate-reducing bacteria. In addition to metal removal, Fe(0) in microcosms also raised the pH from 3.1 to 6.5, and decreased the oxidation redox potential from initial values of 249 to -226 mV, providing more favorable conditions for microbial sulfate reduction. mFe(0) and gFe(0) in combination with glycerol were found to enhance microbial sulfate reduction. However, no sulfate reduction occurred in the controls without Fe(0) or in the microcosm amended with nFe(0). A separate dose test confirmed the inhibition for sulfate reduction in presence of nFe(0). Hydrogen produced by Fe(0) was not capable of supporting microbial sulfate reduction as a lone electron donor in this study. Microbial analysis revealed that the addition of Fe(0) and glycerol shifted the microbial community towards Desulfosporosinus sp. from a population initially dominated by low pH and metal-resisting Acidithiobacillus ferrooxidans., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
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91. Guar gum coupled microscale ZVI for in situ treatment of CAHs: continuous-flow column study.
- Author
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Velimirovic M, Simons Q, and Bastiaens L
- Subjects
- Adenosine Triphosphate analysis, Bacteria classification, Bacteria genetics, Bacteria metabolism, Galactans metabolism, Hydrocarbons, Chlorinated analysis, Hydrocarbons, Chlorinated chemistry, Mannans metabolism, Plant Gums metabolism, RNA, Ribosomal, 16S genetics, Soil Microbiology, Water Pollutants, Chemical analysis, Water Pollutants, Chemical chemistry, Environmental Restoration and Remediation methods, Galactans chemistry, Iron chemistry, Mannans chemistry, Plant Gums chemistry
- Abstract
A column study was performed under in situ conditions to evaluate to which extend the inactivation of the microscale zerovalent iron (mZVI) by guar gum occurs under continuous flow conditions. Five aquifer containing columns were set up under different conditions. Efficient removal of trichloroethene was observed for the column amended by mZVI. Stabilization of the mZVI with guar gum led to slightly reduced activity. More reduced reactivity was observed in the poisoned column containing guar gum stabilized mZVI. This confirms that soil microorganisms can degrade guar gum and that subsequent removal of the oligosaccharides by the groundwater flow (flushing effect) can reactivate the mZVI. After more than six months of continuous operation the columns were dismantled. DNA-based qPCR analysis revealed that mZVI does not significantly affect the bacterial community, while guar gum stabilized mZVI particles can even induce bacterial growth. Overall, this study suggests that the temporarily decreased mZVI reactivity due to guar gum, has a rather limited impact on the performance of in situ reactive zones. The presence of guar gum slightly reduced the reactivity of iron, but also slowed down the iron corrosion rate which prolongs the life time of reactive zone., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2014
- Full Text
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92. Microbial dechlorination activity during and after chemical oxidant treatment.
- Author
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Doğan-Subaşı E, Bastiaens L, Boon N, and Dejonghe W
- Subjects
- Chloroflexi genetics, Chloroflexi metabolism, Gene Dosage, Genes, Bacterial, Hydrogen-Ion Concentration, Oxidation-Reduction, RNA, Bacterial genetics, RNA, Ribosomal, 16S genetics, Chloroflexi drug effects, Oxidants pharmacology, Potassium Permanganate pharmacology, Sodium Compounds pharmacology, Soil Pollutants metabolism, Sulfates pharmacology, Trichloroethylene metabolism
- Abstract
Potassium permanganate (PM) and sodium persulfate (PS) are used in soil remediation, however, their compatibility with a coinciding or subsequent biotreatment is poorly understood. In this study, different concentrations of PM (0.005-2g/L) and PS (0.01-4.52 g/L) were applied and their effects on the abundance, activity, and reactivation potential of a dechlorinating enrichment culture were investigated. Expression of the tceA, vcrA and 16S rRNA genes of Dehalococcoides spp. were detected at 0.005-0.01 g/L PM and 0.01-0.02 g/L PS. However, with 0.5-2g/L PM and 1.13-4.52 g/L PS no gene expression was recorded, neither were indicator molecules for total cell activity (Adenosine triphosphate, ATP) detected. Dilution did not promote the reactivation of the microbial cells when the redox potential was above -100 mV. Similarly, inoculated cells did not dechlorinate trichloroethene (TCE) above -100 mV. When the redox potential was decreased to -300 mV and the reactors were bioaugmented for a second time, dechlorination activity recovered, but only in the reactors with 1.13 and 2.26 g/L PS. In conclusion, our results show that chemical oxidants can be combined with a biotreatment at concentrations below 0.5 g/L PM and 1g/L PS., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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93. Impact of carbon, oxygen and sulfur content of microscale zerovalent iron particles on its reactivity towards chlorinated aliphatic hydrocarbons.
- Author
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Velimirovic M, Larsson PO, Simons Q, and Bastiaens L
- Subjects
- Carbon chemistry, Groundwater chemistry, Hydrocarbons analysis, Models, Chemical, Oxygen chemistry, Particle Size, Sulfur chemistry, Water Pollutants, Chemical analysis, Environmental Restoration and Remediation methods, Hydrocarbons chemistry, Iron chemistry, Metal Nanoparticles chemistry, Water Pollutants, Chemical chemistry
- Abstract
Zerovalent iron (ZVI) abiotically degrades several chlorinated aliphatic hydrocarbons (CAHs) via reductive dechlorination, which offers perspectives for in situ groundwater remediation applications. The difference in reactivity between ZVI particles is often linked with their specific surface area. However, other parameters may influence the reactivity as well. Earlier, we reported for a set of microscale zerovalent iron (mZVI) particles the disappearance kinetic of different CAHs which were collected under consistent experimental conditions. In the present study, these kinetic data were correlated with the carbon, oxygen and sulfur content of mZVI particles. It was confirmed that not only the specific surface area affects the disappearance kinetic of CAHs, but also the chemical composition of the mZVI particles. The chemical composition, in addition, influences CAHs removal mechanism inducing sorption onto mZVI particles instead of dechlorination. Generally, high disappearance kinetic of CAHs was observed for particles containing less oxygen. A high carbon content, on the other hand, induced nonreactive sorption of the contaminants on the mZVI particles. To obtain efficient remediation of CAHs by mZVI particles, this study suggested that the carbon and oxygen content should not exceed 0.5% and 1% respectively. Finally, the efficiency of the mZVI particles may be improved to some extent by enriching them with sulfur. However, the impact of sulfur content on the reactivity of mZVI particles is less pronounced than that of the carbon and oxygen content., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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94. Reactivity screening of microscale zerovalent irons and iron sulfides towards different CAHs under standardized experimental conditions.
- Author
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Velimirovic M, Larsson PO, Simons Q, and Bastiaens L
- Subjects
- Kinetics, Environmental Restoration and Remediation methods, Ferrous Compounds chemistry, Hydrocarbons, Chlorinated chemistry, Iron chemistry
- Abstract
A standardized batch test procedure was developed and used to evaluate the reactivity of twelve newly designed microscale zerovalent iron (mZVI) particles and two biogenic iron sulfides towards a mixture of chlorinated aliphatic hydrocarbons (CAHs) and their breakdown products. For comparison, commercially available mZVIs, nanoscale zerovalent irons (nZVIs), iron sulfides (FeS) and granular zerovalent iron were also tested. Reactivity of the particles was based on observed (kobs) and mass normalized (kM) pseudo-first-order degradation rate constants, as well as specific surface area normalized reaction rate constants (kSA). Sorption characteristics of the particles were based on mass balance data. Among the new mZVIs, significant differences in reactivity were observed and the most reactive particles were identified. Based on kM data, nZVI degraded the examined contaminants one to two orders of magnitude faster than the mZVIs. kM values for biogenic iron sulfides were similar to the least reactive mZVIs. On the other hand, comparison of kSA data revealed that the reactivity of some newly designed mZVIs was similar to highly reactive nZVIs, and even up to one order of magnitude higher. kSA values for biogenic iron sulfides were one to two orders of magnitude lower than those reported for reactive mZVIs., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
- Full Text
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95. Sulfur and oxygen isotope tracing in zero valent iron based In situ remediation system for metal contaminants.
- Author
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Kumar N, Millot R, Battaglia-Brunet F, Négrel P, Diels L, Rose J, and Bastiaens L
- Subjects
- Metals analysis, Oxygen Isotopes analysis, Sulfur Isotopes analysis, Water Pollutants, Chemical analysis, Environmental Restoration and Remediation methods, Groundwater chemistry, Metals chemistry, Water Pollutants, Chemical chemistry
- Abstract
In the present study, controlled laboratory column experiments were conducted to understand the biogeochemical changes during the microbial sulfate reduction. Sulfur and oxygen isotopes of sulfate were followed during sulfate reduction in zero valent iron incubated flow through columns at a constant temperature of 20±1°C for 90 d. Sulfur isotope signatures show considerable variation during biological sulfate reduction in our columns in comparison to abiotic columns where no changes were observed. The magnitude of the enrichment in δ(34)S values ranged from 9.4‰ to 10.3‰ compared to initial value of 2.3‰, having total fractionation δS between biotic and abiotic columns as much as 6.1‰. Sulfur isotope fractionation was directly proportional to the sulfate reduction rates in the columns. Oxygen isotopes in this experiment seem less sensitive to microbial activities and more likely to be influenced by isotopic exchange with ambient water. A linear relationship is observed between δ(34)S and δ(18)O in biotic conditions and we also highlight a good relationship between δ(34)S and sulfate reduction rate in biotic columns., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
96. Reactivity recovery of guar gum coupled mZVI by means of enzymatic breakdown and rinsing.
- Author
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Velimirovic M, Chen H, Simons Q, and Bastiaens L
- Subjects
- Adsorption, Enzymes metabolism, Galactans chemistry, Hydrocarbons, Chlorinated chemistry, Hydrocarbons, Chlorinated metabolism, Iron chemistry, Mannans chemistry, Plant Gums chemistry
- Abstract
Microscale zerovalent iron (mZVI) reduces chlorinated aliphatic hydrocarbons (CAHs) to harmless compounds, but the sedimentation of the mZVI particles in the injection fluid limits the injectability of the particles during field applications. In this study, mZVI particles in suspension were stabilized by green polymer guar gum, which had a positive impact on mZVI stability, but decreased the reactivity of the particles towards CAHs by 1 to 8 times. Guar gum (GG) was found to adsorb onto the mZVI surface, inhibiting contact between the chlorinated compounds and the reactive iron surface. Indications were found for intermolecular hydrogen bonding between mZVI and the guar gum. Subsequent addition of commercially available enzymes resulted in the cleavage of the polysaccharide guar gum into lower molecular fragments, but not in improved reactivity. The reactivity recovery of guar gum coupled mZVI was recovered after intensive rinsing of the iron particles, removing the guar gum fragments from the particles. Overall, this study shows that CAHs can be treated efficiently by guar gum stabilized mZVI after reactivation by means of enzymatic breakdown and rinsing., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2012
- Full Text
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97. Improvement in global psychopathology increases quality of life during treatment of ADHD with atomoxetine or stimulants.
- Author
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Bastiaens L
- Subjects
- Atomoxetine Hydrochloride, Child, Female, Follow-Up Studies, Humans, Male, Psychiatric Status Rating Scales, Statistics, Nonparametric, Adrenergic Uptake Inhibitors therapeutic use, Attention Deficit Disorder with Hyperactivity drug therapy, Attention Deficit Disorder with Hyperactivity psychology, Central Nervous System Stimulants therapeutic use, Propylamines therapeutic use, Quality of Life
- Abstract
To evaluate what determines the increase in quality of life during treatment for ADHD: improvement in core ADHD symptoms or improvement in global psychopathology ratings. A prospective follow-up of ADHD patients in one community clinic. Standardized evaluation and outcome measures were used, including the Mini International Neuropsychiatric Interview, Child Symptom Inventory, 18 item ADHD rating scale, and the Health and Life Functioning Scale. 75 patients between the ages of 6 and 12 were treated with atomoxetine or stimulants with a stable dose for 10 months. At end point, there were modest improvements in ADHD symptoms, global psychopathology, level of functioning and quality of life. The improvement in quality of life was driven by a decrease in global psychopathology, not by a decrease in ADHD symptoms. The treatment for ADHD may need to be broadened beyond the core symptoms. A chronic disease management model may well be applicable.
- Published
- 2011
- Full Text
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98. Integrated evaluation of the performance of a more than seven year old permeable reactive barrier at a site contaminated with chlorinated aliphatic hydrocarbons (CAHs).
- Author
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Muchitsch N, Van Nooten T, Bastiaens L, and Kjeldsen P
- Subjects
- Bacteria metabolism, Environmental Monitoring, Groundwater microbiology, Hydrocarbons, Chlorinated chemistry, Iron chemistry, Iron metabolism, Time Factors, Environmental Restoration and Remediation instrumentation, Groundwater chemistry, Hydrocarbons, Chlorinated analysis, Water Purification instrumentation
- Abstract
An important issue of concern for permeable reactive iron barriers is the long-term efficiency of the barriers due to the long operational periods required. Mineral precipitation resulting from the anaerobic corrosion of the iron filings and bacteria present in the barrier may play an important role in the long-term performance. An integrated study was performed on the Vapokon permeable reactive barrier (PRB) in Denmark by groundwater and iron core sample characterization. The detailed field groundwater sampling carried out from more than 75 well screens up and downstream the barrier showed a very efficient removal (>99%) for the most important CAHs (PCE, TCE and 1,1,1-TCA). However, significant formation of cis-DCE within the PRB resulted in an overall insufficient efficiency for cis-DCE removal. The detailed analysis of the upstream groundwater revealed a very heterogeneous spatial distribution of contaminant loading into the PRB, which resulted in that only about a quarter of the barrier system is treating significant loads of CAHs. Laboratory batch experiments using contaminated groundwater from the site and iron material from the core samples revealed that the aged iron material performed equally well as virgin granular iron of the same type based on determined degradation rates despite that parts of the cored iron material were covered by mineral precipitates (especially iron sulfides, carbonate green rust and aragonite). The PCR analysis performed on the iron core samples indicated the presence of a microbial consortium in the barrier. A wide range of species were identified including sulfate and iron reducing bacteria, together with Dehalococcoides and Desulfuromonas species indicating microbial reductive dehalogenation potential. The microbes had a profound effect on the performance of the barrier, as indicated by significant degradation of dichloromethane (which is typically unaffected by zero valent iron) within the barrier., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
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99. Microbially mediated clinoptilolite regeneration in a multifunctional permeable reactive barrier used to remove ammonium from landfill leachate contamination: laboratory column evaluation.
- Author
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Nooten TV, Diels L, and Bastiaens L
- Subjects
- Adsorption, Bacteria metabolism, Biodegradation, Environmental, Cations, Metals chemistry, Refuse Disposal methods, Waste Disposal, Fluid methods, Water Pollutants chemistry, Water Pollutants, Chemical, Quaternary Ammonium Compounds chemistry, Soil Pollutants chemistry, Water Purification methods, Zeolites chemistry
- Abstract
This study focuses on multifunctional permeable reactive barrier (multibarrier) technology, combining microbial degradation and abiotic ion exchange processes for removal of ammonium from landfill leachate contamination. The sequential multibarrier concept relies on the use of a clinoptilolite-filled buffer compartment to ensure a robust ammonium removal in case of temporary insufficient microbial activities. An innovative strategy was developed to allow in situ clinoptilolite regeneration. Laboratory-scale clinoptilolite-filled columns were first saturated with ammonium, using real landfill leachate as well as synthetic leachates as feed media. Other inorganic metal cations, typically present in landfill leachate, had a detrimental influence on the ammonium removal capacity by competing for clinoptilolite exchange sites. On the other hand, the metals had a highly favorable impact on regeneration of the saturated material. Feeding the columns with leachate deprived from ammonium (e.g., by microbial nitrification in an upgradient compartment), resulted in a complete release of the previously sorbed ammonium from the clinoptilolite, due to exchange with metal cations present in the leachate. The released ammonium is then available for microbial consumption in a downgradient compartment. The regeneration process resulted in a slightly increased ammonium exchange capacity afterward. The described strategy throws a new light on sustainable use of sorption materials for in situ groundwater remediation, by avoiding the need for material replacement and the use of external chemical regenerants.
- Published
- 2010
- Full Text
- View/download PDF
100. A non-randomized, open study with aripiprazole and ziprasidone for the treatment of aggressive behavior in youth in a community clinic.
- Author
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Bastiaens L
- Subjects
- Adolescent, Aggression psychology, Aripiprazole, Child, Community Mental Health Centers, Female, Humans, Male, Treatment Outcome, Aggression drug effects, Antipsychotic Agents therapeutic use, Piperazines therapeutic use, Quinolones therapeutic use, Thiazoles therapeutic use
- Abstract
Forty-six patients (36 male, mean age 11.9 +/- 2.6) with a variety of diagnoses and with significant aggressive behavior were treated in an open, non-randomized fashion with Aripiprazole or Ziprasidone. Patients were diagnosed with the Mini International Neuropsychiatric Interview and the Child/Adolescent Symptom Inventory. The primary outcome measure was the Overt Aggression Scale (OAS). After 2 months, 34 patients were still in treatment. The average improvement of the OAS in these 34 patients was 63%. Clinical Global Impression-Improvement Scale was 2.1 +/- 1.2. Neither at baseline, nor at 2 months, were there any statistically significant differences between the Aripiprazole and Ziprasidone groups. Sedation was the most common side effect.
- Published
- 2009
- Full Text
- View/download PDF
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