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See detailIsolation and identification of anthropogenic particles in fish stomachs by Raman spectroscopy: a new method
Collard, France ULg; Gilbert, Bernard ULg; Eppe, Gauthier ULg et al

in Organohalogen Compounds (2015, August)

Microplastic particles (MP) contaminate oceans and affect marine organisms in several ways. Ingestion combined with food intake is generally reported. However, data interpretation is often circumvented by ... [more ▼]

Microplastic particles (MP) contaminate oceans and affect marine organisms in several ways. Ingestion combined with food intake is generally reported. However, data interpretation is often circumvented by the difficulty to separate MP from bulk samples. Visual examination is often used as one or the only step to sort these particles. However, color, size and shape are insufficient and often unreliable criteria. Here we present an isolation method of MP specially adapted to a subsequent analysis by Raman spectroscopy. This method avoids fluorescence problems allowing the identification anthropogenic particles (AP) from stomach contents of fish by Raman spectroscopy. It was validated with commercial samples of microplastics and cotton along with stomach contents from three different Clupeiformes fishes: Clupea harengus, Sardina pilchardus and Engraulis encrasicolus. The optimized digestion and isolation protocol showed no visible impact on microplastics and cotton particles while the spectroscopic analysis allowed precise identification of microplastics and textile fibers. This approach allowed us to isolate 35 particles. These were analyzed by Raman spectroscopy: eleven were microplastics and thirteen were made of cellulose or lignin, or both (mostly fibers). Some particles were not identified but contained artificial colorants. This isolation protocol will help to assess the presence, quantity and composition of AP in planktivorous fish stomachs. [less ▲]

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See detailIsolation and identification of antioxidant phytochemicals from Cuban species of the genera Erythroxylum P. Browne and Pluchea Cass
Perera Cordova, Wilmer ULg

Doctoral thesis (2012)

Phytochemicals showing antioxidant properties are largely recognized as beneficial to human health and disease prevention. Cuba is well known for having a rich flora with a high percentage of endemic ... [more ▼]

Phytochemicals showing antioxidant properties are largely recognized as beneficial to human health and disease prevention. Cuba is well known for having a rich flora with a high percentage of endemic species; it is considered as an interesting source of plant species for searching bioactive metabolites. Polar and non-polar extracts were prepared by fractionation from macerations in ethanol: H2O (7:3 v/v) from several Cuban plant species. The antioxidant capacity and the concentration in phenolic compounds were assayed in these extracts. The native species Pluchea carolinensis (Jacq.) G. Don., Pluchea odorata (L.) Cass. and Pluchea rosea Godfrey were identified as the most promising sources of antioxidants. The n-butanol extracts obtained by reflux from endemic Erythroxylum alaternifolium A. Rich. var. alaternifolium, var. parvifolium and suborbiculare also displayed high antioxidant capacity and high levels in phenolic compounds. The antioxidant capacity and the phenolic content of hydroalcoholic macerations from leaves, inflorescences, stems and roots of species of the genus Pluchea were also compared. Leaf extracts followed by inflorescence extracts showed the highest values of antioxidant capacity. The species P. carolinensis was used as a model to evaluate the antioxidant capacity in two locations and two phenological stages and also for monitoring the antioxidant capacity over some months. Natural adult specimens presented a higher phenolic content, as well as higher antioxidant capacity than young and cultivated specimens. Maximal antioxidant capacity and concentrations in phenolics were recorded in January, September and December; over the blooming stage (March), the antioxidant capacity was minimal. Two different solvents of extraction and two methods were also screened for extracting the maximal concentrations in antioxidants. Hydroalcoholic extractions showed higher antioxidant capacity than ethanolic ones. However, no difference in antioxidant capacity were measured between the two methods of extraction. The antioxidant capacity of P. carolinensis was also measured in leaves of plantlets micro-propagated on three different in vitro culture media and it was compared with leaves of young specimens grown ex-vitro. The inclusion of a cytokinin in culture media increased the antioxidant capacity of the leaf extracts of plantlets grown in vitro. However, the antioxidant capacity of plantlets grown in vitro was lower than that of young specimens grown ex-vitro. Additionally, several phenolic compounds were isolated from the species studied. Two flavonol glycosides were isolated from n-butanol leaf extract of Erythroxylum alaternifolium var. alaternifolium. Moreover, 22 phenolic compounds (including 9 phenolic acids and 13 flavonoids) were also identified from leaf, inflorescence and stem extracts of the three Pluchea species. All of them are reported for the first time in Cuban Pluchea species. In addition, rosmarinic acid, ferulic acid, quercetagetin, herbacetin, quercitrin, eupalitin and 3-methyl-quercetagetin were described for the first time in the genus Pluchea. The antioxidant capacity of each of these compounds was evaluated. The results suggested that most of these phytochemicals have an important contribution to the antioxidant capacity found in plant extracts. [less ▲]

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See detailIsolation and identification of dominant osmophilic Leuconostoc strains from traditional date product “Btana”
Abekhti, Abdelkader; Daube, Georges ULg; Kihal, M.

in International Food Research Journal [=IFRJ] (2014), 21(4), 1261-1268

The current study aimed to isolate and identify dominant osmophilic bacteria associated with a traditional date product named “Btana”, produced in south region of Maghreb countries. Samples were randomly ... [more ▼]

The current study aimed to isolate and identify dominant osmophilic bacteria associated with a traditional date product named “Btana”, produced in south region of Maghreb countries. Samples were randomly collected after two month of storage from tow villages (Mtarfat and Abani) in the Algerian southern department “Adrar”. A high osmotic pressure medium (MSE) was used for isolation of osmophilic bacteria, which were purified and examined for macroscopic and microscopic shape, Gram stain, catatalse, oxydase, acetoine and ADH production, reduction of nitrate, and motility. Isolates were then subculture on MRS medium for production of dextran, gas from glucose, growth in the presence of NaCl (3, 6.5 %) and sucrose (10, 20, 30, 40, and 50 %), pH tolerance (4.8, 6.5), growth temperature (10, 37, and 45°C) and thermo resistance (55°C for 15 min), enzymatic activity (proteolytic, lipolytic, hemolysis). Isolates were identified to specie’s level by sugar fermentation. Their growth and acidification kinetic were also studied. Results identified two species of Leuconostoc; Leuconostoc mesenteroides subsp. mesenteroides and Leuconostoc mesenteroides subsp. dextranicum. They show a high antibacterial activity against four indicator bacteria; Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. [less ▲]

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See detailIsolation and identification of inulooligosaccharides resulting from inulin hydrolysis
Ronkart, Sebastien N; Blecker, Christophe ULg; Fourmanoir, Hélène et al

in Analytica Chimica Acta (2007), 604(1), 81-87

In this study, inulooligosaccharides (F-n-type inulin) resulting from the endo-inulinase hydrolysis of globe artichoke inulin were purified and characterized. The aim was to produce F-n oligomer standards ... [more ▼]

In this study, inulooligosaccharides (F-n-type inulin) resulting from the endo-inulinase hydrolysis of globe artichoke inulin were purified and characterized. The aim was to produce F-n oligomer standards with the intention of identifying them in the complex inulin chromatogram. Inulin was extracted from globe artichoke and presented a high average degree of polymerization (DP) of about 80 as determined by high-performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD). This inulin was hydrolyzed by a commercial endo-inulinase yielding a product with a very high F-n/GF(n), molecule ratio, thus limiting the interference of GF(n) during the purification process. High performance size exclusion chromatography was used to individually isolate and collect each retention peak corresponding to a specific oligomer. The purity of these fractions was checked by HPAEC-PAD and showed that relatively pure molecules were produced. Electrospray ionization mass spectrometry allowed the molecular weight determination of these purified oligomers and ascertained their DP as F-2, F-3 and F-4. These F2-4 standards were used with glucose, fructose, sucrose and GF(2-4) (commercially available) to spike commercial oligofructose products in order to determine the elution profile in the HPAEC-PAD chromatogram. [less ▲]

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See detailIsolation and identification of potential antimalarial compounds from endemic plants of Reunion Island
Bordignon, Annélise ULg; Cieckiewicz, Ewa ULg; Jansen, Olivia ULg et al

Poster (2015, July 16)

Malaria is known as the most important parasitic disease around the world with 584 000 malaria deaths worldwide in 2013 [1]. Due to the problem of increased parasite resistance, natural products from ... [more ▼]

Malaria is known as the most important parasitic disease around the world with 584 000 malaria deaths worldwide in 2013 [1]. Due to the problem of increased parasite resistance, natural products from endemic plants of Reunion Island, hot spot of promising biodiversity, could represent an important source of new antimalarial drugs. The aim of this thesis research focuses on the evaluation of potential antiplasmodial activity of medicinal plants from Reunion Island. A global screening of plants extracts from Reunion Island was performed on Plasmodium falciparum 3D7 chloroquine-sensitive strain revealed by colorimetric method as described in previous reports [2]. Monimia rotundifolia was then selected due to its promising in vitro activity against Plasmodium. Bioguided fractionation was realized using Prep HPLC techniques and led to the isolation of aporphine-type alkaloids from Monimia rotundifolia leaves dichloromethane extract. Further investigations are in process to confirm the antiplasmodial activities of these alkaloids and to determine their structures. References: [1] WHO, World Malaria report 2014. [2] Jansen O. et al., Evaluation of 13 selected medicinal plants from Burkina Faso for their antiplasmodial properties. J Ethnopharmacol 2010, 130:143-150. [less ▲]

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See detailIsolation and Identification of Steroid and Flavonoid Glycosides from the Flowers of Allium gramineum
Mskhiladze, Lasha; Chincharadze, David; St-Gelais, Alexis et al

in International Journal of Pharmaceutical Sciences and Drug Research (2016), 8(4), 240-243

The isolation and identification of β-sitosterol 3-O-β-glucopyranoside, quercetin 3-O-β-glucopyranoside, isorhamnetin 3,4'-di-O-β-glucopyranosideand isorhamnetin 3,7-di-O-β-glucopyranosidefrom the flowers ... [more ▼]

The isolation and identification of β-sitosterol 3-O-β-glucopyranoside, quercetin 3-O-β-glucopyranoside, isorhamnetin 3,4'-di-O-β-glucopyranosideand isorhamnetin 3,7-di-O-β-glucopyranosidefrom the flowers of Allium gramineumthat growsin Georgia.The structures of isolated compounds havebeen determined by 1H and 13C nuclear magnetic resonance (NMR) Isolation and Identification of Steroid and Flavonoid Glycosides from the Flowers of Allium gramineum. Available from: https://www.researchgate.net/publication/305851744_Isolation_and_Identification_of_Steroid_and_Flavonoid_Glycosides_from_the_Flowers_of_Allium_gramineum [accessed Aug 5, 2016]. [less ▲]

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See detailIsolation and identification of two new fungal strains for xylanase production
Bakri, Y.; Masson, M.; Thonart, Philippe ULg

in Applied Biochemistry and Biotechnology (2010), 162(6), 1626-1634

Fungi are well known for their ability to excrete enzymes into the environment. The aim of this work was to evaluate xylanase production by fungi isolated from soil. One hundred and thirty-six fungal ... [more ▼]

Fungi are well known for their ability to excrete enzymes into the environment. The aim of this work was to evaluate xylanase production by fungi isolated from soil. One hundred and thirty-six fungal isolates were screened for xylanase production. Two xylanase producing isolates, FSS117 and FSS129, were identified on the basis of analyses of 5,8S gene sequencing. The closest phylogenetic neighbors according to 5,8S gene sequence data for the two isolates were Aspergillus tubingensis and Aspergillus terreus, respectively. When birchwood xylan or corn cob hulls was used as a substrate for 5 days under submerged culture cultivation, xylanase production from A. terreus FSS129 was 113 and 174 IU ml -1, respectively. The pH and temperature for optimum xylanase activity were 8 and 65∈°C. © 2010 Springer Science+Business Media, LLC. [less ▲]

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See detailIsolation and long-term cultivation of human tonsil follicular dendritic cells.
Tsunoda, R.; Nakayama, M.; Onozaki, K. et al

in Virchows Archiv. B : Cell pathology (1990), 59(2), 95-105

Highly purified follicular dendritic cells (FDC) were isolated from human tonsils and cultivated for up to 150 days. The cell separation method employed produced pure aggregates (FDC-clusters) composed of ... [more ▼]

Highly purified follicular dendritic cells (FDC) were isolated from human tonsils and cultivated for up to 150 days. The cell separation method employed produced pure aggregates (FDC-clusters) composed of FDC and germinal center lymphoid cells, useful for the analysis of the relationship between these two cell types and of the behavior of FDC in culture. During the first few days of culture, lymphoid cells located between FDC extensions survived better than those which were free or partly covered by FDC. After 6 days, the lymphoid population degenerated and only the FDC survived. The unique antigenic pattern of FDC (positive for HLA-DR. DRC-1, CD14b, CD21, CD23, CD35) disappeared within a few days of culture. Recombinant interferon-gamma exerted a positive effect either on retaining HLA-DR expression or on the reexpression of these antigens by FDC. HLA-ABC antigens were traced until the 10th day and desmosomal junctions until the 14th day. Subsequently, FDC presented peculiar features, including oval and rhomboid shapes, one to ten nuclei, fine amoeboid extensions, stress fibers and a radical dense zone in their cytoplasm. FDC possessed actin, tubulin and vimentin, but neither desmin nor cytokeratin. After 40 days of culture, FDC enlarged and were covered with abundant membrane extensions. Even when kept as long as 150 days in vitro. FDC did not proliferate in any of the culture conditions employed. [less ▲]

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See detailIsolation and Partial Characterization of a Pregnancy-Associated Glycoprotein Family from the Goat Placenta
Garbayo, Juana Maria; Remy, Benoit; Alabart, José Luis et al

in Biology of Reproduction (1998), 58(1), 109-115

Antigen(s) immunologically related to pregnancy-associated glycoproteins (PAGs) have previously been detected in the serum of pregnant goats. In this work, we describe a partial characterization of a ... [more ▼]

Antigen(s) immunologically related to pregnancy-associated glycoproteins (PAGs) have previously been detected in the serum of pregnant goats. In this work, we describe a partial characterization of a family of PAGs isolated from the placenta of the goat. The procedure, monitored by RIA, included extraction of proteins at neutral pH, acidic, and ammonium sulfate precipitations; and gel filtration and ion exchange chromatographies. Immunoreactivity, initially located in the acidic supernatant and in the 40-80% ammonium sulfate fractions, was equally apportioned between the 0.04 and 0.08 M NaCl DEAE fractions. After further purification of both DEAE fractions, the preparations were subjected to one- and two-dimensional electrophoresis, and individual polypeptides were analyzed by amino acid sequencing. Three PAGs, which differed in amino acid sequence and apparent molecular masses (62, 59, and 55 kDa), were detected, each containing several isoforms with different pls: caprine (c) PAG62 (pl: 5.1, 4.8), cPAG59 (pl: 6.2, 5.9, 5.6), and cPAG55 (pl: 5.3, 5.1, 4.9). These proteins had high sequence identities to each other and to PAGs purified from other species. Each had two putative N-glycosylation sites within the 27 amino terminal residues sequenced. This work demonstrates that PAGs are present in goat placenta and that multiple forms are expressed. [less ▲]

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See detailIsolation and partial characterization of three pregnancy-associated glycoproteins from the ewe placenta
El Amiri, B.; Remy, Benoit; Melo de Sousa, Noelita ULg et al

in Molecular Reproduction and Development (2003), 64(2), 199-206

Pregnancy-associated glycoproteins (PAGs) are synthesized in the outer epithelial layer of the placenta in artiodactyls. In this work, three novel ovine PAGs were isolated from late-pregnancy fetal ... [more ▼]

Pregnancy-associated glycoproteins (PAGs) are synthesized in the outer epithelial layer of the placenta in artiodactyls. In this work, three novel ovine PAGs were isolated from late-pregnancy fetal cotyledons and characterized biochemically. The isolation procedure included acid and ammonium sulfate precipitations and anion and cation exchange chromatographies. The isolated PAGs have different NH2-terminal amino acid sequences (RGSXLTILPLRNMRDIVY, ISRVSXLTIHPLRNIMDML, and RGSNLTIHPLRNIRD) and apparent molecular masses (55, 57, and 59 kDa). Each shows several isoforms with different pl values. The three proteins share high sequence identity with each other and with other ovine, bovine, and caprine PAGs. They have not been described previously. The ovPAG-59 sequence differs from the previously identified ovPAG-4 sequence (determined by DNA cloning and sequencing) at only one position among the 15 N-terminal residues. The newly characterized ovPAGs and the procedure used to isolate them will be helpful in producing new antisera for investigating PAG secretion in pregnant ewes. [less ▲]

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See detailIsolation and partial purification of pregnancy-associated glycoproteins from sheep placenta
El Amiri, Bouchra; Remy, Benoit; Sulon, Joseph ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2001), 5(1), 23-24

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See detailIsolation and pharmacological activity of phenylpropanoid esters from Marrubium vulgare
Sahpaz, S.; Garbacki, Nancy ULg; Tits, Monique ULg et al

in Journal of Ethnopharmacology (2002), 79(3), 389-392

The isolation and identification of major phenylpropanoid esters from Marrubium vulgare: (+) (E)-caffeoyl-L-malic acid 1, acteoside 2, forsythoside B 3, arenarioside 4, ballotetroside 5, as well as their ... [more ▼]

The isolation and identification of major phenylpropanoid esters from Marrubium vulgare: (+) (E)-caffeoyl-L-malic acid 1, acteoside 2, forsythoside B 3, arenarioside 4, ballotetroside 5, as well as their anti-inflammatory activity are reported for the first time, We evaluated the inhibitory effects of these five compounds on cyclooxygenase (Cox) catalysed prostaglandin biosynthesis activity. Only the glycosidic phenylpropanoid esters showed an inhibitory activity towards the Cox-2 enzyme and three of them: acteoside 2, forsythoside B 3, arenarioside 4, exhibited higher inhibitory potencies on Cox-2 than on Cox-1. These results are of interest, as Cox-2 is mainly associated with inflammation and the Cox-1 inhibition with adverse side effects often observed with non-steroidal anti-inflammatory drugs. The occurence of these phenylpropanoid esters could also explain some other pharmacological properties of M. vulgare. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. [less ▲]

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See detailIsolation and pharmacological characterization of AdTx1, a natural peptide displaying specific insurmountable antagonism of the alpha1A-adrenoceptor
Quinton, Loïc ULg; Girard, E.; Maiga, A. et al

in British Journal of Pharmacology (2010), 159

Venoms are a rich source of ligands for ion channels, but very little is known about their capacity to modulate G-protein coupled receptor (GPCR) activity. We developed a strategy to identify novel toxins ... [more ▼]

Venoms are a rich source of ligands for ion channels, but very little is known about their capacity to modulate G-protein coupled receptor (GPCR) activity. We developed a strategy to identify novel toxins targeting GPCRs. Experimental approach: We studied the interactions of mamba venom fractions with a1-adrenoceptors in binding experiments with 3H-prazosin. The active peptide (AdTx1) was sequenced by Edman degradation and mass spectrometry fragmentation. Its synthetic homologue was pharmacologically characterized by binding experiments using cloned receptors and by functional experiments on rabbit isolated prostatic smooth muscle [less ▲]

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See detailIsolation and preliminary characterisation of a filamentous terrestrial red alga.
Hoffmann, Lucien; Garbacki, Nancy ULg

Conference (1999)

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See detailIsolation and purification of bovine immunoglobins : use of Sephacryl S-300 filtration avoids protein precipitation steps.
Collard, Alfred; Pivont, P.; Portetelle, Daniel ULg et al

in Annales de Recherches Vétérinaires = Annals of Veterinary Research (1984), 15

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See detailIsolation and Purification of Panarine, a Quaternary Alkaloid from a Venezuelian Curare
Quetin-Leclercq, Joëlle; Angenot, Luc ULg; Dupont, Léon et al

in Phytochemistry (1988), 27(12), 4002-4004

High Speed Counter Current Chromatography (HSCCC) has been used to isolate and purify two quaternary alkaloids from a sample of curare prepared by the Panare Indians of Estado Bolivar, Venezuela. One of ... [more ▼]

High Speed Counter Current Chromatography (HSCCC) has been used to isolate and purify two quaternary alkaloids from a sample of curare prepared by the Panare Indians of Estado Bolivar, Venezuela. One of the compounds is the known base Macusine B. The other one is a new but related base named panarine. Its structure has been established unequivocally by spectral and X-ray cristallographic analysis. [less ▲]

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See detailIsolation and Quantification of Lactic Acid Bacteria from Traditional Fermented Products in Benin
Tchekessi, C.K.C.; Bokossa, I.Y; Azokpota, P. et al

in International Journal of Current Microbiology and Applied Sciences (2014), 3(11), 1-8

In Africa, fermented food products are particularly used as weaning foods for young children, pregnant women and the seniors. In Benin, most of these cereals-based foods are manufactured and sold around ... [more ▼]

In Africa, fermented food products are particularly used as weaning foods for young children, pregnant women and the seniors. In Benin, most of these cereals-based foods are manufactured and sold around the streets. These are ablo, dèguè, akpan, abotin, gowé etc ... This study focused on the isolation and enumeration of bacteria and yeast from twenty six (26) samples of traditional African fermented foods. Decimal dilution method allowed us to isolate a total of 42 different strains of microorganisms among which we counted 30 lactic acid bacteria. They confirmed their biological potential by expanding in selective medium MRS. When they were then subjected to screening, the medium of MRS-broth-starch agar, and eight (08) of the isolated strains tested showed their characters of amylolytic strains. The eight strains isolated were tested and finally cultivated at temperatures and pH ranging respectively from 30°C to 60°C and 3.0 to 6.5. These eight (08) amylolytic lactic acid bacteria (ALAB) synthesized enzyme amylase both inside and outside the bacterial cell with a very interesting activity value. The temperature limit between 40 and 45°C is best for the bacteria 26.2, B16 and B18 while the optimum pH for amylase synthesis is between 4.0 and 4.5 for the same microorganisms that have given the largest values of enzyme activity. The best strains 26.2, B16 and B18 secrete more enzymes in extracellular medium than intracellular. [less ▲]

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See detailIsolation and Radioimmunoassay Formation of Equine Osteocalcin- Preliminary Results
Carstanjen, B; Sulon, J; Banga-Mboko, H et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2002), 6(1), 8-9

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See detailIsolation and radioimmunoassay of a bovine pregnancy specific protein.
Beckers, Jean-François ULg; Wouters-Ballman, P.; Ectors, F.

in Theriogenology (1988, January), 29(1), 219

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