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Determination of non-steroidal anti-inflammatory drugs in natural waters using off-line and on-line SPE followed by LC coupled with DAD-MS
PublicationOpisano dwie metody pozwalające na jednoczesne oznaczanie zawartości niesterydowych leków przeciwzapalnych (difluisal, diklofenak, naproksen, tolmetin, fenoprofen, ibuprofen) w próbkach wodnych. Próbki przygotowywano do analizy z użyciem techniki ekstrakcji do fazy stałej (off-line i on-line). Natomiast oznaczeń końcowych dokonano z użyciem LC-DAD-MS. Sprawdzono kilka różnych kolumienek ekstrakcyjnych i wybrano RP-18 jako najlepsze...
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Modification of gradient HPLC method for determination of small molecules' affinity to human serum albumin under column safety conditions: Robustness and chemometrics study
PublicationIn the early stages of drug discovery, beyond the biological activity screening, determining the physicochemical properties that affect the distribution of molecules in the human body is an essential step. Plasma protein binding (PPB) is one of the most important investigated endpoints. Nevertheless, the methodology for measuring %PPB is significantly less popular and standardized than other physicochemical properties, like lipophilicity....
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Determination of phenylbutazone, sulfamethazine, carbendazim and linuron using a novel pine bark biosorbent for solid-phase extraction (SPE) with high-performance liquid chromatography (HPLC)
PublicationThe paper presents a novel pine bark based biosorbent for solid-phase extraction (SPE). The morphology and composition of the pine bark were characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The biosorbent was used for the preparation of wastewater for the determination of phenylbutazone, sulfamethazine, carbendazim, and linuron by high performance liquid chromatography with...
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Application of dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry for the determination of oxygenated volatile organic compounds in effluents from the production of petroleum bitumen
PublicationWepresent a new procedure for the determination of oxygenated volatile organic compounds in samples of postoxidative effluents from the production of petroleum bitumens using dispersive liquid–liquid microextraction and gas chromatography with mass spectrometry. The eight extraction parameters were optimized for 43 oxygenated volatile organic compounds. The detection limits obtained ranged from 0.07 to 0.82 g/mL for most of the...
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Determination of free tyrosine in equestrian supplements by LC–MS/MS and comparison of its quantity with total free amino acids content in view of doping control
PublicationThe reports on the probable beneficial impact of tyrosine (TYR) supplementation on performance enhancement have contributed to the growth of interest in TYR in equestrian sports field and related industries, such as the manufacture of dietary and nutritional supplements. In this study, the first attempt to the assessment of horses exposure to TYR during nutritional supplementation was demonstrated by quantification of unbound TYR...
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Natural deep eutectic solvent based ultrasound assisted liquid-liquid micro-extraction method for methyl violet dye determination in contaminated river water
PublicationSimple and green natural deep eutectic solvent (NADES) based ultrasound assisted liquid-liquid micro-extraction (UA-LLME) method was developed for extraction and determination of methyl violet dye in contaminated river water samples using UV/Vis spectrophotometry. Choline chloride - decanoic acid based natural deep eutectic solvent was used for extraction. Important analytical parameters like pH, deep eutectic solvent volume/phase...
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Spectrophotometric determination of chlorpyrifos in foodstuffs after vortex-assisted surfactant-enhanced emulsification microextraction using magnetic deep eutectic solvents: Analytical greenness profile
PublicationIn this work a novel and green vortex-assisted surfactant-enhanced emulsification microextraction (VA-SEEME) based on magnetic deep eutectic solvents (MDESs) was developed for the determination of chlorpyrifos in foodstuffs by UV-Vis spectrophotometric analysis. MDES (trihexyltetradecylphosphonium chloride: MnCl2: octanoic acid) was used as the extractant, non-ionic surfactant Tween-80 was used as an extraction medium, and ethanol...
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Determination of bromhexine and its metabolites in equine serum samples by liquid chromatography – Tandem mass spectrometry: Applicability to the elimination study after single oral dose
PublicationBromhexine (BH), expectorant used in the treatment of respiratory disorders associated with viscid or excessive mucus, is not permitted for use in the competing horse by many authorities in horseracing and Olympic disciplines. Metabolic studies are of the great importance in anti-doping field because they allow for updating the selection of the most appropriate markers for prohibited substances, such as metabolites present at higher...
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Alkyl polyglycoside-assisted separation followed by smartphone-based digital image colorimetry for on-site determination of total phenolic content in plant-based milk alternatives
PublicationA low-cost lab-on-a-smartphone platform for rapid and on-site assessment of total phenolic content in plant-based milk alternatives has been proposed for the first time. The three main components, including a smartphone, a disposable Eppendorf vial and a specially designed holder with an integrated polychromatic light source, were compactly assembled to enable color-forming reaction, separation and measurement. The method involves...
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Determination of urinary androgens in women with polycystic ovary syndrome using LC-QqQ/MS and the application of thin film solid-phase microextraction (TF-SPME)
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Determination of tributyltin in marine sediment: Comit� Consultatif pour la Quantit� de Mati�re (CCQM) pilot study P-18 international intercomparison
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Optimisation of pressurised liquid extraction for elimination of sulphur interferences during determination of organotin compounds in sulphur-rich sediments by gas chromatography with flame photometric detection
PublicationOpracowano metodę analizy osadów dennych na zawartość związków cynoorganicznych (MBT, DBT, TBT, MPhT, DPhT, TPhT) przy użyciu przyspieszonej ekstrakcji rozpuszczalnikiem i chromatografii gazowej z detektorem płomieniowo-fotometrycznym. Detektor ten pozwala selektywnie wykrywać niewielkie ilości pochodnych cynoorganicznych. Niestety, bardzo często spotykana w osadach siarka oraz jej pochodne zakłócają sygnał detektora. Z tego względu...
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Spectrofluorometrical Determination of Vitamin B 1 in Different Matrices Using Box‐Behnken Designed Pipette Tip Solid Phase Extraction by a Carbon Nanotube Sorbent
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Application of molecularly imprinted polymer pipette tip micro-solid phase extraction of nalidixic acid and acetaminophen from pills and seawater samples and their determination by spectrophotometry
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Fast determination of bisphenol A in spiked juice and drinking water samples by pipette tip solid phase extraction using cobalt metal organic framework as sorbent
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Application of In-Syringe Dispersive Liquid–Liquid Microextraction and Narrow-Bore Tube Dispersive Liquid–Liquid Microextraction for the Determination of Trace Amounts of BTEX in Water Samples
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DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS IN SOIL SAMPLES USING ULTRASONIC PROBE AND SALT-ASSISTED LIQUID-LIQUID EXTRACTION COUPLED WITH HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY
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Determination of mefenamic acid in urine and pharmaceutical samples by HPLC after pipette-tip solid phase microextraction using zinc sulfide modified carbon nanotubes
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Application of response surface methodology to optimize pipette tip micro-solid phase extraction of dyes from seawater by molecularly imprinted polymer and their determination by HPLC
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Fabrication of a Molecularly Imprinted Polymer Adsorbent for Pipette Tip Micro Solid-phase Extraction of Levofloxacin from Aqueous Samples Prior to its Spectrophotometric Determination
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Determination of pharmaceutical residues in drinking water in Poland using a new SPE-GC-MS(SIM) method based on Speedisk extraction disks and DIMETRIS derivatization
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Solid-Contact Ion-Selective Electrodes with Highly Selective Thioamide Derivatives of p-tert-Butylcalix[4]arene for the Determination of Lead(II) in Environmental Samples
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Określenie szybkości korozji stopu AlSi13Mg1CuNi nadtopionego laserowo w warunkach kriogenicznych = Corrosion rate determination of AlSi13Mg1CuNi alloy laser remelted at cryogenic conditions
PublicationW pracy przedstawiono wyniki badania szybkości korozji stopu AlSi13Mg1CuNi nadtopionego laserowo w warunkach kriogenicznych. Stop eksponowano w 0,01 M roztworze kwasu siarkowego H2SO4
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Ultrasound assisted dispersive solid phase microextraction using polystyrene-polyoleic acid graft copolymer for determination of Sb(III) in various bottled beverages by HGAAS
PublicationA new polyoleic acid-polystyrene (PoleS) block/graft copolymer was synthesized and applied as adsorbent for ultrasound assisted dispersive solid phase microextraction (UA-DSPME) of Sb(III) in different bottled beverages and analysis using hydride generation atomic absorption spectrometry (HGAAS). Adsorption capacity of the PoleS was 150 mg g−1. Several sample preparation parameters such as sorbent amount, solvent type, pH, sample...
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Determination of denaturation temperature of connective tissue proteins by viscometric measurements.
Open Research DataViscometric denaturation temperature of connective tissue proteins was determined by measuring viscosity with a Brookfield viscometer, using a LV SC4 - 18, 25 or LV3 spindle and shear rates from 50 to 110 s-1 (Fig.1). Freeze-dried protein samples were dissolved in 0.5 M acetic acid at 4 °C and concentration of 20 mg/mL. The solution was stirred with...
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Determination of viscosity changes in dietary supplement solutions depending on temperature.
Open Research DataThe rheological characteristics of dietary supplement solutions were made based on viscosity measurement using a Brookfield viscometer, using the LV SC4 - 18 spindle and a shear rate of 53 s-1 (Fig.1).
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Determination of changes in viscosity of chitosan solutions depending on shear rate.
Open Research DataThe rheological characteristics of chitosan solutions were based on viscosity measurements using a Brookfield viscometer, using LV SC4 - 25 spindles and shear rates from 4 to 53 s-1 (Fig. 1). Chitosan solutions with different molecular weights (low, medium and high) were prepared in concentrations from 1.5 to 3.0% in 0.5M acetic acid. The data allowed...
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Determination of eight artificial sweeteners and common Stevia rebaudiana glycosides in non-alcoholic and alcoholic beverages by reversed-phase liquid chromatography coupled with tandem mass spectrometry.
PublicationThe method for the determination of acesulfame-K, saccharine, cyclamate, aspartame, sucralose, alitame, neohesperidin dihydrochalcone, neotame and five common steviol glycosides (rebaudioside A, rebaudioside C, steviol, steviolbioside and stevioside) in soft and alcoholic beverages was developed using high-performance liquid chromatography and tandem mass spectrometry with electrospray ionisation (HPLC-ESI-MS/MS). To the best of...
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Determination of parent and methylated polycyclic aromatic hydrocarbons in water samples by dispersive liquid–liquid microextraction–two dimensional gas chromatography–time-of-flight mass spectrometry
PublicationPolycyclic aromatic hydrocarbons (PAHs) are contaminants frequently found in environmental waters. Owing to their toxic effects, it is important to develop analytical methodologies that allow their fast and reliable determination. Dispersive liquid–liquid microextraction (DLLME) allows a quick extraction of analytes with little organic solvent consumption. The best results regarding sample preparation are obtained when 40 mL of...
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Current trends in analytical strategies for determination of polybrominated diphenyl ethers (PBDEs) in samples with different matrix compositions – Part 1.: Screening of new developments in sample preparation
PublicationPolybrominated diphenyl ethers (PBDEs) are ubiquitous compounds in the environment. Restrictions on the use of PBDEs introduced at the beginning of the 21st century have not eliminated these highly persistent and bioaccumulative compounds from the environment. Despite many existing regulations to control and phase out, extensive research on PBDEs is still necessary to fully evaluate the hazard their create to the environment. In...
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Chromium‑based metal organic framework for pipette tip micro‑solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples
PublicationAbstract Background A chromium-based metal organic framework was synthesized and employed as an efficient sorbent for pipette tip micro-solid phase extraction and preconcentration of parabens from wastewater and shampoo samples up to sub-ppb level before their spectrophotometric analysis. Results Factors affecting preconcentration including volume and type of solvent, amount of sorbent, number of extraction, and volume and pH of...
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Multi-residue method for the determination of 16 recently used pesticides from various chemical groups in aqueous samples by using DI - SPME coupled with GC-MS
PublicationA simple and solvent-free multi-residue method has been optimized to determine 16 currently used pesticides from different chemical groups in aqueous samples. The extraction of analytes was carried out with direct immersion solid-phase microextraction (DI-SPME) and for the identification and quantitative determination gas chromatography coupled with mass spectrometry (GC-MS) was applied. Two commonly used adsorbent coatings have...
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Novel liquid chromatography method based on linear weighted regression for the fast determination of isoprostane isomers in plasma samples using sensitive tandem mass spectrometry detection
PublicationA simple, fast, sensitive and accurate methodology based on a LLE followed by liquid chromatography–tandem mass spectrometry for simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in routine analysis of human plasma samples was developed. Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the...
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Sensitive method for determination of benzoic acid in beverages and food samples using air–assisted hydrophobic deep eutectic solvent-based dispersive liquid-liquid microextraction
PublicationA simple, reliable and rapid air–assisted hydrophobic deep eutectic solvent-based dispersive liquid–liquid microextraction (AA-HDES-DLLME) was developed for analysis of benzoic acid in various beverages and food samples. The final determination stage was performed via UV–visible spectrophotometry. The key parameters (extraction time, HDES type and volume, dispersant volume, pH and sample volume) of the AA-HDES-DLLME method were...
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Ultrasound assisted solvent extraction of porous membrane-packed samples followed by liquid chromatography-tandem mass spectrometry for determination of BADGE, BFDGE and their derivatives in packed vegetables
PublicationThe problem of the presence of trace organic pollutants in food is of growing importance due to increasing awareness about their impact on newborns, infants and adults of reproductive age. Despite the fact that packaged food products offer many advantages, packaging can be a source of contamination for stored food. Thus, monitoring such pollution in food is of high importance. In this work, a novel methodology based on the solvent...
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Comparison of hydrophilic interaction and reversed phase liquid chromatography coupled with tandem mass spectrometry for the determination of eight artificial sweeteners and common steviol glycosides in popular beverages
PublicationHydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MS/MS) was used to separate artificial and natural sweeteners approved for use in European Union (EU). Among three tested HILIC columns (BlueOrchid PAL-HILIC, Ascentis Express Si and Acclaim™ Trinity™ P2) the last one was selected for the development of HILIC method due to the best results obtained with it. Early eluting and coeluting compounds...
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Wyznaczanie współczynników dyfuzji tlenku węgla (IV) przez membrany wysycone cieczą jonową = Determination of carbon dioxide diffusion coefficients in supported ionic liquids membranes
PublicationWykazano możliwość zastosowania imidazoliowych cieczy jonowych osadzonych na nośnikach polimerowych SILM (supported ionic liquids membranes) do absorpcji CO2. W badaniach wykorzystano sole imidazoliowe posiadające w strukturze aniony fluoroalkilowe typu [Tf2N] i [TfO], które selektywnie separują tlenek węgla (IV). Wyznaczono współczynniki dyfuzji CO2 przez poszczególne SILM na podstawie ilości dyfundującego CO2 przez powierzchnię...
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Use of porous glass and silica gel as support media of a surface compound for generation of analytes in gaseous standard mixtures. New method for the determination of the amount of analyte generated
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Przegląd metod oznaczania pozostałości pestycydów i polichlorowanych bifenyli w próbkach żywności = Methods of determination of residues of pesticides and polychlorinated biphenyls in food samples - a review
PublicationOznaczanie pozostałości pestycydów i analitów z grupy polichlorowanych bifenyli w próbkach żywności wymaga zastosowania specyficznych technik w zakresie przygotowania próbki do analizy, jak i samych technik analizy instrumentalnej, pozwalających na uzyskanie bardzo niskiej granicy oznaczalności. Problemem związanym ze stosowaniem związków z grupy pestycydów i polichlorowanych bifenyli jest konieczność kontroli ich pozostałości...
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Determination of profenofos in seawater and foodstuff samples after its molecularly imprinted polymer pipette-tip micro solid phase extraction optimized by response surface methodology
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Application of response surface methodology for optimization of metal–organic framework based pipette-tip solid phase extraction of organic dyes from seawater and their determination with HPLC
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Comparison of Air-Assisted, Vortex-Assisted and Ultrasound-Assisted Dispersive Liquid–Liquid Microextraction for the Determination of BTEX Compounds in Water Samples Prior to GC-FID Analysis
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Problemy z oznaczaniem zawartości fazy stałej z zastosowaniem normy ISO 8292 = Problems with the solid fat content determination using the ISO 8292 standard.
PublicationZawartość fazy stałej (SFC) jest parametrem charakteryzującym właściwości fizyczne i użytkowe tłuszczów stałych. Otrzymanie prawidłowego wyniku zależy od zastosowania odpowiedniej procedury termostatowania próbki przed pomiarem, a ta z zależy od rodzaju badanego tłuszczu. Przed oznaczeniem SFC wszystkie TAG, które są stałe w temperaturze 0oC powinny wykrystalizować, a tłuszcz osiągnąć trwałą formę krystaliczną. Pierwsza norma IUPAC...
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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublicationSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublicationA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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Determination of mechanical properties of human stomach tissues subjected to uniaxial stretching
Open Research DataThe aim of the study was to determine the biomechanical properties of the walls of the human stomach. The samples were fragments of the human stomach obtained after sleeve gastrectomy. Samples cut parallel to the stomach curves and perpendicular to the stomach curves were tested in each series. All samples were subjected to uniaxial stretching. During...
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Determination of viscosity changes of protein hydrolyzate solutions depending on shear rate
Open Research DataRheological characteristics of connective tissue protein solutions were made on the basis of viscosity measurement using a Brookfield viscometer using LV SC4 - 27 spindles and shear rate of 85 s-1 (Fig. 1). Solutions of protein hydrolysates with a concentration of 2% in 0.5M acetic acid were prepared.
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Determination of changes in viscosity of chitosan cosmetic preparations depending on shear rate.
Open Research DataThe rheological characteristics of chitosan were made on the basis of a viscosity measurement using a Brookfield viscometer, using LV SC4 - 25 spindles and shear rates from 0.3 to 32 s-1 (Fig. 1). Chitosan solutions at 1% concentrations in acetic acid were prepared. The samples were subjected to storage tests.
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Determination of the ratio resistors in the input circuits of the NTC10k thermistor calibration system
Open Research DataThe presented data set is part of the research aimed at determining the actual characteristics of each thermistor in a package of twenty NTC10k type sensors.
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Determination of tributyltin (TBT) in marine sediment using pressurised liquid extraction–gas chromatography–isotope dilution mass spectrometry (PLE–GC–IDMS) with a hexane–tropolone mixture
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