Pub Date : 2024-02-26DOI: 10.1177/87560879241234946
Barry A Morris
Since its inception nearly 100 years ago, flexible packaging has seen tremendous growth due to its ability to meet packaging needs at the lowest cost and with the least amount of material usage. The modern era of flexible packaging began in the early twentieth century with the introduction of cellophane, a transparent “wonder” film which enabled the development of large distribution channels of pre-packaged goods and changed consumer lifestyles and buying habits. New processes and materials have continually advanced flexible packaging technology. In concert, the scientific understanding of materials and polymer processing has progressed. This paper traces the history of flexible packaging, describing major developments in technology and the science behind them. Flexible packaging has constantly evolved to meet new demands and challenges. This bodes well for the future as the industry address its end-of-life shortcomings and moves towards a more circular economy. Learnings from the past, guided by improved scientific insight and engineering principles, can be leveraged to adapt flexible packaging to changing market, societal and regulatory demands.
{"title":"Flexible packaging past, present and future: Reflections on a century of technology advancement","authors":"Barry A Morris","doi":"10.1177/87560879241234946","DOIUrl":"https://doi.org/10.1177/87560879241234946","url":null,"abstract":"Since its inception nearly 100 years ago, flexible packaging has seen tremendous growth due to its ability to meet packaging needs at the lowest cost and with the least amount of material usage. The modern era of flexible packaging began in the early twentieth century with the introduction of cellophane, a transparent “wonder” film which enabled the development of large distribution channels of pre-packaged goods and changed consumer lifestyles and buying habits. New processes and materials have continually advanced flexible packaging technology. In concert, the scientific understanding of materials and polymer processing has progressed. This paper traces the history of flexible packaging, describing major developments in technology and the science behind them. Flexible packaging has constantly evolved to meet new demands and challenges. This bodes well for the future as the industry address its end-of-life shortcomings and moves towards a more circular economy. Learnings from the past, guided by improved scientific insight and engineering principles, can be leveraged to adapt flexible packaging to changing market, societal and regulatory demands.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"44 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139980299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This research investigated and developed a laminate packaging film of poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) containing modified chitosan nanoparticles (MCSNPs) treated with 3-(trimethoxysilyl)propyl methacrylate silane (TMSPM) which functioned both as a reinforcement and as an antimicrobial filler. Electron beam irradiation caused crosslink between the PVA and MCSNP molecules via the free radical of carbonyl in the methacrylate group of TMSPM-grafted chitosan nanoparticles and the free radical of hydroxyl group in poly(vinyl alcohol). This improved the PVA hydrophobicity. In addition, the laminate with PVA-g-MCSNPs film irradiated with a 30 kGy electron beam showed the best performance properties due to improved interfacial adhesion between PLA and PVA-g-MCSNPs. As a consequence, the mechanical and thermal properties improved. The 30 kGy irradiated film also had better antibacterial activity against both Escherichia coli and Staphylococcus aureus.
{"title":"Improvement of PLA-PVA/chitosan nanocomposite laminate film for packaging via crosslinking with electron beam irradiation: Mechanical, thermal and antimicrobial analysis","authors":"Thawanrat Chaisit, Punnanee Sumpavapol, Thitirat Rattanawongwiboon, Kittisak Jantanasakulwong, Thorsak Kittikorn","doi":"10.1177/87560879241233704","DOIUrl":"https://doi.org/10.1177/87560879241233704","url":null,"abstract":"This research investigated and developed a laminate packaging film of poly(lactic acid) (PLA) and poly(vinyl alcohol) (PVA) containing modified chitosan nanoparticles (MCSNPs) treated with 3-(trimethoxysilyl)propyl methacrylate silane (TMSPM) which functioned both as a reinforcement and as an antimicrobial filler. Electron beam irradiation caused crosslink between the PVA and MCSNP molecules via the free radical of carbonyl in the methacrylate group of TMSPM-grafted chitosan nanoparticles and the free radical of hydroxyl group in poly(vinyl alcohol). This improved the PVA hydrophobicity. In addition, the laminate with PVA-g-MCSNPs film irradiated with a 30 kGy electron beam showed the best performance properties due to improved interfacial adhesion between PLA and PVA-g-MCSNPs. As a consequence, the mechanical and thermal properties improved. The 30 kGy irradiated film also had better antibacterial activity against both Escherichia coli and Staphylococcus aureus.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"253 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2024-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139949945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-05DOI: 10.1177/87560879231204207
Hafiz Muhammad Atif, Fariha Jabeen, Muhammad Asif Javed
Roll-coating, also known as roll-to-roll coating or web coating is a continuous and high-speed method used in various industrial applications to apply a thin and uniform layer of material onto a substrate. This process is commonly employed in industries such as electronics, photovoltaic, printing, packaging, and other fields where precise and consistent coating is essential. Here we present an asymptotic analysis of forward roll coating over a rigid substrate for low Weissenberg number viscoelastic fluids. The analysis uses lubrication theory coupled with regular perturbation theory assuming a simplified Phan-Thien-Tanner (SPPT) constitutive equation and small values of the extensibility parameter ε. The analytical expressions of velocity fields, pressure gradient and pressure fields are obtained while the load carrying force, and power input are estimated by numerical solutions (4 th order Runge-Kutta). Increases in both Wi and ε increases the pressure gradient in the nip region and increases in viscoelasticity reduce the overall force on the roll. Further, SPTT model predicts 14% lower pressure for [Formula: see text] in the nip region when compared to Newtonian model.
{"title":"Mathematical study of viscoelastic polymer during roll-over-web coating","authors":"Hafiz Muhammad Atif, Fariha Jabeen, Muhammad Asif Javed","doi":"10.1177/87560879231204207","DOIUrl":"https://doi.org/10.1177/87560879231204207","url":null,"abstract":"Roll-coating, also known as roll-to-roll coating or web coating is a continuous and high-speed method used in various industrial applications to apply a thin and uniform layer of material onto a substrate. This process is commonly employed in industries such as electronics, photovoltaic, printing, packaging, and other fields where precise and consistent coating is essential. Here we present an asymptotic analysis of forward roll coating over a rigid substrate for low Weissenberg number viscoelastic fluids. The analysis uses lubrication theory coupled with regular perturbation theory assuming a simplified Phan-Thien-Tanner (SPPT) constitutive equation and small values of the extensibility parameter ε. The analytical expressions of velocity fields, pressure gradient and pressure fields are obtained while the load carrying force, and power input are estimated by numerical solutions (4 th order Runge-Kutta). Increases in both Wi and ε increases the pressure gradient in the nip region and increases in viscoelasticity reduce the overall force on the roll. Further, SPTT model predicts 14% lower pressure for [Formula: see text] in the nip region when compared to Newtonian model.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135482011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-25DOI: 10.1177/87560879231204135
{"title":"Industry News","authors":"","doi":"10.1177/87560879231204135","DOIUrl":"https://doi.org/10.1177/87560879231204135","url":null,"abstract":"","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135816926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-23DOI: 10.1177/87560879231204143
Huqiu Zhang
Government agencies around the world regulate food contact materials or articles. Understanding these regulations and keeping up with the new regulations are essential for maintaining market access for food contact products. My intent is to provide global plastics food contact regulation developments and updates relevant to plastic film and sheet for food packaging.
{"title":"Global food contact regulation updates for 4<sup>th</sup> quarter 2023","authors":"Huqiu Zhang","doi":"10.1177/87560879231204143","DOIUrl":"https://doi.org/10.1177/87560879231204143","url":null,"abstract":"Government agencies around the world regulate food contact materials or articles. Understanding these regulations and keeping up with the new regulations are essential for maintaining market access for food contact products. My intent is to provide global plastics food contact regulation developments and updates relevant to plastic film and sheet for food packaging.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135966532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-22DOI: 10.1177/87560879231204134
John R. Wagner
{"title":"From the Editor","authors":"John R. Wagner","doi":"10.1177/87560879231204134","DOIUrl":"https://doi.org/10.1177/87560879231204134","url":null,"abstract":"","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136061304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-19DOI: 10.1177/87560879231204142
Shari Kraber
The purpose of running a statistically designed experiment (DOE) is to take a strategically selected small sample of data from a larger system, and then extract a prediction equation that appropriately models the overall system. The statistical tool used to relate the independent factors to the dependent responses is analysis of variance (ANOVA). This article will lay out the key assumptions for ANOVA and how to verify them using graphical diagnostic plots. The first assumption (and one that is often overlooked) is that the chosen model is correct. This means that the terms in the model explain the relationship between the factors and the response, and there are not too many terms (over-fitting), or too few terms (underfitting). One should not use the raw R-squared statistic as it is misleading. Please see Journal of Plastic Film& Sheeting Volume 37, Number 4, page 405, “R-squared mysteries solved” which explains how to interpret raw versus adjusted versus predicted R-squared.
{"title":"Dive into diagnostics for DOE model discrepancies","authors":"Shari Kraber","doi":"10.1177/87560879231204142","DOIUrl":"https://doi.org/10.1177/87560879231204142","url":null,"abstract":"The purpose of running a statistically designed experiment (DOE) is to take a strategically selected small sample of data from a larger system, and then extract a prediction equation that appropriately models the overall system. The statistical tool used to relate the independent factors to the dependent responses is analysis of variance (ANOVA). This article will lay out the key assumptions for ANOVA and how to verify them using graphical diagnostic plots. The first assumption (and one that is often overlooked) is that the chosen model is correct. This means that the terms in the model explain the relationship between the factors and the response, and there are not too many terms (over-fitting), or too few terms (underfitting). One should not use the raw R-squared statistic as it is misleading. Please see Journal of Plastic Film& Sheeting Volume 37, Number 4, page 405, “R-squared mysteries solved” which explains how to interpret raw versus adjusted versus predicted R-squared.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135014055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-10DOI: 10.1177/87560879231186142
F. Kharrat, M. Khlif, L. Hilliou, J. Covas, M. Haboussi, C. Bradai
The bulge test is a versatile mechanical testing technique widely applied in materials science, engineering, and biomedical research to understand the mechanical behavior of materials and structures. In this study, PLA blown films were characterized through the bulge test, and the corresponding properties were compared to those obtained from uniaxial t!esting. To achieve more accurate and precise deformation measurements, 3D digital image correlation (3D-DIC) was used, offering superior capabilities in terms of accuracy, precision, and non-destructive testing. This technique can detect defects such as cracks, voids, and delamination in materials and structures. During the bulge testing, 3D-DIC was utilized to analyze the strain field evolution within the test sample and identify regions of reduced film thickness. Notably, the results indicated zones with strain concentration aligned parallel to the film machine direction, suggesting localized thickness reduction in those areas.
{"title":"Application of the bulge test combined with 3D-DIC for biaxial characterization of PLA films and defect detection","authors":"F. Kharrat, M. Khlif, L. Hilliou, J. Covas, M. Haboussi, C. Bradai","doi":"10.1177/87560879231186142","DOIUrl":"https://doi.org/10.1177/87560879231186142","url":null,"abstract":"The bulge test is a versatile mechanical testing technique widely applied in materials science, engineering, and biomedical research to understand the mechanical behavior of materials and structures. In this study, PLA blown films were characterized through the bulge test, and the corresponding properties were compared to those obtained from uniaxial t!esting. To achieve more accurate and precise deformation measurements, 3D digital image correlation (3D-DIC) was used, offering superior capabilities in terms of accuracy, precision, and non-destructive testing. This technique can detect defects such as cracks, voids, and delamination in materials and structures. During the bulge testing, 3D-DIC was utilized to analyze the strain field evolution within the test sample and identify regions of reduced film thickness. Notably, the results indicated zones with strain concentration aligned parallel to the film machine direction, suggesting localized thickness reduction in those areas.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"22 1","pages":"447 - 469"},"PeriodicalIF":3.1,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79404905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Welchen Platz nimmt Queerness in der deutschen Post-Wende-Nation ein? Und welche Erzählungen von Nation und Queerness bieten queere deutsche Filme in der Nachwendezeit an? Jeanette Roche zeigt aus intersektionaler Perspektive, dass dort eine Reihe von Möglichkeiten queerer Subjektpositionen für das Verhältnis zur Nation nach '89 entstehen. Sie reflektiert dabei die im Film aufkommenden Ambivalenzen zwischen Normalisierungsnarrativen und deren Umformung. Dabei wird deutlich: Der Diskurs um Nationalismus findet immer auch sexualisiert und vergeschlechtlicht statt.
{"title":"Queere Nation?","authors":"Jeanette Roche","doi":"10.14361/9783839468418","DOIUrl":"https://doi.org/10.14361/9783839468418","url":null,"abstract":"Welchen Platz nimmt Queerness in der deutschen Post-Wende-Nation ein? Und welche Erzählungen von Nation und Queerness bieten queere deutsche Filme in der Nachwendezeit an? Jeanette Roche zeigt aus intersektionaler Perspektive, dass dort eine Reihe von Möglichkeiten queerer Subjektpositionen für das Verhältnis zur Nation nach '89 entstehen. Sie reflektiert dabei die im Film aufkommenden Ambivalenzen zwischen Normalisierungsnarrativen und deren Umformung. Dabei wird deutlich: Der Diskurs um Nationalismus findet immer auch sexualisiert und vergeschlechtlicht statt.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"16 1","pages":""},"PeriodicalIF":3.1,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85977785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-03DOI: 10.1177/87560879231190574
Indira Husić, A. Mahendran, Judith Sinic, C. Jocham, H. Lammer
In the current study, we report the progress in developing new UV polymerizable hydrophobic biobased coatings from modified vegetable oil for porous substrates like paper and wood. The aim was to produce novel hydrophobic coatings on porous substrates and investigate how the porous nature of the substrates will be affected by different chemical formulations that penetrate into the interior of the substrate during the exposure to different intensities of UV light, and what hydrophobic properties that interaction will result in. The curing formulations were based on acrylated epoxidized linseed oil (AELO) as a prepolymer. For the UV polymerization, 1-hydroxycyclohexyl phenyl ketone (Irgacure 184) was used as a photoinitiator; isobornyl acrylate (IBA) and isosorbide methacrylate (IM) were used as bio-based diluents; hexadecyltrimethoxysilane (HDTMS), vinyl-polydimethylsiloxane (v-PDMS), triethoxyoctylsilane (TEOS) were used as hydrophobic additives and they were added in different concentrations to the AELO curing formulations. The formulations were then cured under UV light on wood and paper substrates. FT-IR analysis showed that the AELO resin was successfully polymerized on both paper and wood substrates, and by contact angle measurements it was found that the highest hydrophobicity was achieved for the coatings that contain HDTMS (108° in average). The layer thickness on wood substrates was in between 9 and 20 µm, and on paper substrates between 8 and 24 µm. Only about a 5° difference in contact angle was observed between the coatings with respect to change in diluents and different UV light intensity. All cured samples showed a good chemical resistance to acetic acid, citric acid and ethyl alcohol after 1 hour exposure; to acetone and ethylbutyl acetate after 10 s, and to benzine after 2 minutes. Outstanding hydrophobic behavior was observed for the HDTMS coatings, however, better physical properties were determined for the coatings containing v-PDMS and TEOS, on which the scratching was observed after the applied force of 1.5 and 0.6 N in comparison to HDTMS coatings (0.4 N). The resulting properties achieved for the AELO coatings indicated that it has a potential to be used for wood coating and packaging application.
{"title":"Interaction of porous substrate and vegetable oil-based hydrophobic thermoset coatings during UV-polymerization","authors":"Indira Husić, A. Mahendran, Judith Sinic, C. Jocham, H. Lammer","doi":"10.1177/87560879231190574","DOIUrl":"https://doi.org/10.1177/87560879231190574","url":null,"abstract":"In the current study, we report the progress in developing new UV polymerizable hydrophobic biobased coatings from modified vegetable oil for porous substrates like paper and wood. The aim was to produce novel hydrophobic coatings on porous substrates and investigate how the porous nature of the substrates will be affected by different chemical formulations that penetrate into the interior of the substrate during the exposure to different intensities of UV light, and what hydrophobic properties that interaction will result in. The curing formulations were based on acrylated epoxidized linseed oil (AELO) as a prepolymer. For the UV polymerization, 1-hydroxycyclohexyl phenyl ketone (Irgacure 184) was used as a photoinitiator; isobornyl acrylate (IBA) and isosorbide methacrylate (IM) were used as bio-based diluents; hexadecyltrimethoxysilane (HDTMS), vinyl-polydimethylsiloxane (v-PDMS), triethoxyoctylsilane (TEOS) were used as hydrophobic additives and they were added in different concentrations to the AELO curing formulations. The formulations were then cured under UV light on wood and paper substrates. FT-IR analysis showed that the AELO resin was successfully polymerized on both paper and wood substrates, and by contact angle measurements it was found that the highest hydrophobicity was achieved for the coatings that contain HDTMS (108° in average). The layer thickness on wood substrates was in between 9 and 20 µm, and on paper substrates between 8 and 24 µm. Only about a 5° difference in contact angle was observed between the coatings with respect to change in diluents and different UV light intensity. All cured samples showed a good chemical resistance to acetic acid, citric acid and ethyl alcohol after 1 hour exposure; to acetone and ethylbutyl acetate after 10 s, and to benzine after 2 minutes. Outstanding hydrophobic behavior was observed for the HDTMS coatings, however, better physical properties were determined for the coatings containing v-PDMS and TEOS, on which the scratching was observed after the applied force of 1.5 and 0.6 N in comparison to HDTMS coatings (0.4 N). The resulting properties achieved for the AELO coatings indicated that it has a potential to be used for wood coating and packaging application.","PeriodicalId":16823,"journal":{"name":"Journal of Plastic Film & Sheeting","volume":"16 1","pages":"427 - 446"},"PeriodicalIF":3.1,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84079493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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