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Copyright of Studies in Conservation is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highly cross-linked polyethylene (HXLPE) was introduced to improve wear in total hip arthroplasty, with manufacturers implementing different thermal treatments to reduce oxidation. It is important to understand how long-term time in vivo affects the wear of these materials. The purpose of this study was to investigate the wear and oxidative performance of first-generation HXLPE hip inserts implanted for greater than 10 years and compare annealed and remelted HXLPE formulations. There were 49 total hip arthroplasty liners retrieved during routine revision surgery as part of an institutional review board–approved implant retrieval program. Penetration rates for the liners were calculated as the difference between the thickness of the unloaded and loaded regions divided by implantation time. Oxidation indices for the rim, locking mechanism, articulating surface, and backside regions were measured using Fourier-transform infrared spectroscopy according to American Society for Testing and Materials 2102. Mann–Whitney U tests were used to determine the statistical difference between annealed and remelted components. The cohort had an average implantation time of 13.1 ± 2.6 years for annealed and 12.1 ± 1.7 years for remelted components. The components were revised most often for polyethylene wear, instability, and loosening. The penetration rate averaged 0.0177 ± 0.014 mm/year for annealed components and 0.015 ± 0.022 mm/year for remelted components. Penetration rates did not differ between the remelted and annealed cohorts (P =.28). Oxidation indices were found to be significantly higher in the annealed cohort for all regions of interest (P <.001). Oxidation was found to be higher in the annealed HXLPE; however, this does not seem to be associated with greater wear as we found the average penetration rates for the cohorts were low, and the penetration rates were similar between the annealed and remelted cohorts. [ABSTRACT FROM AUTHOR]

After clinical introduction in 2005, sequentially annealed, highly cross-linked polyethylene (SA HXLPE) was studied for retrievals with short implantation times; however, long-term follow-ups are lacking. The objective of this study was to examine and compare the revision reasons, damage mechanisms, and oxidation indices of SA HXLPE and conventional gamma inert–sterilized (Gamma Inert) ultra-high-molecular-weight polyethylene tibial inserts implanted for >5 years. There were 74 total knee arthroplasty tibial inserts (46 SA HXLPEs, 28 Gamma Inerts) implanted for >5 years (mean 7 ± 2 years) retrieved as part of a multicenter retrieval program. Cruciate-retaining implants comprised 44% of the SA HXLPEs and 14% of the Gamma Inerts. Patient factors and revision reasons were collected from revision operating notes. A semiquantitative scoring method was used to assess surface damage mechanisms. Oxidation was measured using Fourier transform infrared microscopy according to American Society for Testing and Materials 2102. Differences between cohorts were assessed with Mann–Whitney U -tests. Loosening (Gamma Inert: 17 of 28, SA HXLPE: 15 of 46) and instability (Gamma Inert: 6 of 28, SA HXLPE: 15 of 46) were the most common revision reasons for both cohorts. The most prevalent surface damage mechanisms were burnishing, pitting, and scratching, with burnishing of the condyles being higher in Gamma Inert components (P =.022). Mean oxidation was higher in the SA HXLPE inserts at the articulating surface (P =.002) and anterior-posterior faces (P =.023). No difference was observed at the backside surface (P =.060). Revision reasons and surface damage mechanisms were comparable in the Gamma Inert and SA cohorts. Further studies are needed to continue to assess the in vivo damage and clinical relevance, if any, of oxidation in SA HXLPE over longer implantation times, particularly for implants implanted for more than 10 years. [ABSTRACT FROM AUTHOR]

This study aims to compare short-term functional outcomes and conversion rates to reverse shoulder arthroplasty between patients who underwent total shoulder arthroplasty (TSA) using a modular metal-backed glenoid component, a hybrid glenoid component, and an all-polyethylene component. A retrospective review of individuals undergoing TSA between October 2014 and December 2020 was performed. Inclusion criteria included patients undergoing primary TSA for osteoarthritis during this time frame by 1 surgeon. Preoperative and postoperative variables included demographic information, American Shoulder and Elbow Surgeons score (ASES), and range of motion. Revision rates were also documented. Summary statistics were performed, using a 1-way analysis of variance with Tukey post hoc pairwise comparisons when the outcome reached significance. Fifty-two patients were included with age averaging 68 ± 8.1 years, with body mass index of 31 ± 5.8. 54% of patients were female with 12% having diabetes and only 2% were smokers. Follow-up averaged 42 months with patients undergoing metal-backed glenoid having longer follow-up at 56.5 months (P <.001). ASES, forward elevation, and external rotation (ER) for every implant type improved significantly postoperatively (P <.001) besides internal rotation and ER within the poly group (P =.072). No difference was found between the 3 groups for preoperative and postoperative ASES scores, forward elevation, internal rotation, and ER (P >.05). Two patients within the poly group required revision due to rotator cuff tear (P =.225). At 2 years, functional outcomes and patient-reported outcomes are similar in all 3 glenoid groups. There were slightly higher revision rates within the all-polyethylene group. If outcomes are similar among all groups, modular implant systems may be favorable to make conversion to revision TSA easier. [ABSTRACT FROM AUTHOR]

In light of the extensive contamination of water sources by microplastics, their substantial specific surface area makes them favorable candidates as adsorbents for the simultaneous removal of coexisting contaminants in wastewater. In this regard, polyethylene microplastics were utilized to eliminate methylene blue dye from water. MB adsorption onto microplastics reached equilibrium in just 30 min at pH 7. The better fit of fractional power and Redlich-Peterson models on kinetic and equilibrium adsorption data, respectively, revealed that the MB removal process is a chemisorption in multilayer adsorption on the heterogeneous surface of the microplastics particles. The reusability of the microplastics adsorbent was confirmed based on the promising outcomes observed after five cycles. The results of the random forest regression exhibited an R2 of 97.55% for the correlation between the model-computed and measured amounts of MB reduction. The sensitivity analysis illustrated that the MB sorption process on microplastics is highly influenced by the initial MB concentration and adsorbent mass. These results show that although microplastics may pose potential risks to water environments, their adsorption potential can be utilized to simultaneously omit other pollutants from the aqueous solutions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess 10-year patient-reported outcome measures, complications, polyethylene wear-rates, and implant survivorships in patients ≤30 years of age treated with contemporary total hip arthroplasty (THA). We retrospectively assessed 121 patients (144 hips) who underwent THA at age ≤30 years (mean 23 [range, 11 to 30]) at an average follow-up duration of 10.7 years (range, 8 to 17). Highly-crosslinked polyethylene acetabular liners were used in all cases. Femoral heads were ceramic (74%) or cobalt-chrome (26%). There were 52 hips (36%) that had previous surgery and 31 hips (22%) were in patients who had associated major systemic comorbidities. We analyzed the modified Harris Hip scores, University of California Los Angeles Activity Scores, major complications, polyethylene wear-rates, and implant survivorships. At final follow-up, the average modified Harris Hip scores improved from 47 (±15.1) to 81 (±19.5) with an average 34-point improvement. The University of California Los Angeles scores improved from 4.0 (±2.3) to 6.0 (±2.4). The major complication rate was 5.6%. There were 6 hips (4.2%) that were revised. Indications for revision included instability (3, 2.1%), late infection (1, 0.7%), liner dissociation (1, 0.7%), and acetabular loosening (1, 0.7%). Mean linear (0.0438 mm/y) and volumetric (29.07 mm3/y) wear rates were low. No periprosthetic osteolysis was detected in any hip. Survivorship free from revision for any reason was 97.2, 95.8, and 95.8% at 5, 10, and 15 years. Contemporary THA in patients ≤30 years of age is associated with marked clinical improvements at 10-year follow-up and encouraging survivorship estimates at 15 years. [ABSTRACT FROM AUTHOR]

Background: Biofilms, such as those from Staphylococcus epidermidis, are generally insensitive to traditional antimicrobial agents, making it difficult to inhibit their formation. Although quercetin has excellent antibiofilm effects, its clinical applications are limited by the lack of sustained and targeted release at the site of S. epidermidis infection. Objectives: Polyethylene glycol-quercetin nanoparticles (PQ-NPs)-loaded gelatin-N,O- carboxymethyl chitosan (N,O-CMCS) composite nanogels were prepared and assessed for the on-demand release potential for reducing S. epidermidis biofilm formation. Methods: The formation mechanism, physicochemical characterization, and antibiofilm activity of PQ-nanogels against S. epidermidis were studied. Results: Physicochemical characterization confirmed that PQ-nanogels had been prepared by the electrostatic interactions between gelatin and N,O-CMCS with sodium tripolyphosphate. The PQ-nanogels exhibited obvious pH and gelatinase-responsive to achieve on-demand release in the micro-environment (pH 5.5 and gelatinase) of S. epidermidis. In addition, PQ-nanogels had excellent antibiofilm activity, and the potential antibiofilm mechanism may enhance its antibiofilm activity by reducing its relative biofilm formation, surface hydrophobicity, exopolysaccharides production, and eDNA production. Conclusions: This study will guide the development of the dual responsiveness (pH and gelatinase) of nanogels to achieve on-demand release for reducing S. epidermidis biofilm formation. [ABSTRACT FROM AUTHOR]

Achieving ultra-high tensile strength and exceptional toughness is a longstanding goal for structural materials. However, previous attempts using covalent and non-covalent bonds have failed, leading to the belief that these two properties are mutually exclusive. Consequently, commercial fibers have been forced to compromise between tensile strength and toughness, as seen in the differences between nylon and Kevlar. To address this challenge, we drew inspiration from the disparate tensile strength and toughness of nylon and Kevlar, both of which are polyamide fibers, and developed an innovative approach that combines specific intermolecular disulfide bonds and reversible hydrogen bonds to create ultra-strong and ultra-tough polyamide spider silk fibers. Our resulting Supramolecular polyamide spider silk, which has a maximum molecular weight of 1084 kDa, exhibits high tensile strength (1180 MPa) and extraordinary toughness (433 MJ/m3), surpassing Kevlar's toughness 8-fold. This breakthrough presents a new opportunity for the sustainable development of spider silk as an environmentally friendly alternative to synthetic commercial fibers, as spider silk is composed of amino acids. Future research could explore the use of these techniques and fundamental knowledge to develop other super materials in various mechanical fields, with the potential to improve people's lives in many ways. • By emulating synthetic commercial fibers such as nylon and polyethylene, we have successfully produced supramolecular-weight polyamide spider silk fibers with a molecular weight of 1084 kDa through a unique covalent bond-mediated linear polymerization reaction of spider silk protein molecules. This greatly surpasses the previous record of a maximum molecular weight of 556 kDa. • We obtained supramolecular polyamide spider silk fibers with both high-tensile strength and toughness. The stress at break is 1180 MPa, and the toughness is 8 times that of kevlar, reaching 433 MJ/m3. • Our results challenge the notion that it is impossible to manufacture fibers with both ultra-high tensile strength and ultra-toughness, and provide theoretical guidance for developing environmentally friendly and sustainable structural materials that meet industrial needs. [Display omitted] [ABSTRACT FROM AUTHOR]

Highly cross-linked polyethylene (HXLPE) acetabular bearing surfaces have appeared to offer excellent wear resistance, low incidence of wear-related osteolysis, and high implant survivorship at 10-year to 15-year follow-up. However, concerns over potential performance deterioration at longer-term follow-up remain — particularly in younger patients — and outcome data into the third decade have not been available. We retrospectively assessed 62 patients (68 hips) who underwent primary total hip arthroplasty (THA) at age ≤50 years with a single manufacturer's cementless components, remelted HXLPE liner, and small diameter (26 and 28 millimeter) cobalt-chromium (CoCr) femoral heads at minimum 18-year follow-up. We assessed clinical outcomes (modified Harris Hip score, University of California Los Angeles Activity Score, polyethylene wear rates, radiographic findings (osteolysis, component loosening), and implant survivorship. At 20.6-year mean follow-up (range, 18 to 23 years) modified Harris Hip scores for surviving hips remained an average of 41 points above preoperative baseline (49 versus 90, P <.001) and UCLA scores 2.8 points above baseline (3.7 versus 6.4, P <.001). Wear analysis revealed a population linear wear rate of 0.0142 mm/y (standard deviation (SD), 0.0471) and volumetric wear rate of 10.14 mm3/y (SD, 23.41). Acetabular lysis was noted in 2 asymptomatic hips at 16.6 and 18.4 years. No components were radiographically loose. Survivorship free from wear-related revision was 100% at 20 years (97% free from any revision). The HXLPE-CoCr bearing couple with small femoral heads continues to be extremely effective 20 years after primary THA in the younger patient population. [ABSTRACT FROM AUTHOR]

We compared the rate of all-cause revision of 2 classes of primary anatomic shoulder arthroplasty, stemmed (stTSA) and stemless (slTSA), undertaken with cemented all-polyethylene glenoid components. A large national arthroplasty registry identified 2 cohort groups for comparison, stTSA and l undertaken for all diagnoses between January 1, 2011, and December 31, 2021. A subanalysis from January 1, 2017, allowed capturing of additional patient demographics including American Society of Anesthesiologists score, body mass index, and glenoid morphology. The cumulative percent revision (CPR) was determined using Kaplan-Meier estimates of survivorship and hazard ratios (HR) from Cox proportional hazard models adjusted for age and gender. Of the 7995 stTSA procedures, the CPR at 9 years was 5.6% (95% confidence interval [CI]: 5.0, 6.4), and for 3156 slTSA procedures, the CPR was 4.4% (95% CI: 3.6, 5.5). There was no significant difference in the rate of revision between the study groups (HR = 0.76 [95% CI: 0.51, 1.14], P =.189, adjusted for age, gender, humeral head size, humeral fixation, bearing surface, glenoid design, and mean surgeon volume [MSV]). There was an increased rate of revision for stTSA and slTSA undertaken with humeral head sizes <44 mm (stTSA <44 mm vs. 44-50 mm, HR = 1.56 [CI: 1.18, 2.08], P =.001; slTSA <44 mm vs. 44-50 mm, HR = 2.08 [CI: 1.32, 3.33], P =.001). MSV as a continuous predictor was not a revision risk to stTSA vs. slTSA, but categorically, a low MSV (<10 stTSA + slTSA cases per annum) was associated with a higher revision rate for stTSA (10-20 cases/yr vs. <10 cases/yr, HR = 0.72 [CI: 0.55, 0.95], P =.019) but was not in slTSA. Revision rates were increased for stTSA with non–crosslinked polyethylene (XLPE) glenoids vs. XPLE after 2 years (HR = 2.20 [CI: 1.57, 3.08], P <.001) but did not significantly differ for slTSA. Metal/XPLE (humeral/glenoid) bearing surface of stTSA rate of revision was not different from each combination of slTSA bearing surface. Instability/dislocation was a revision risk for slTSA vs. stTSA (HR = 1.93 [CI: 1.28, 2.91], P =.001), but from 2017, neither of American Society of Anesthesiologists score, body mass index, and glenoid morphology changed the rate of revision. Revision rates of stTSA and slTSA did not significantly differ and were associated with humeral head size but not patient characteristics. Surgeon inexperience of anatomic shoulder arthroplasty and non-XLPE glenoids were risk factors for stTSA revision but not slTSA. The metal/XLPE stTSA rate of revision was not found to differ significantly from slTSA regardless of polyethylene or humeral head bearing type. Revision for instability/dislocation was more common for slTSA. [ABSTRACT FROM AUTHOR]

The long-term use of pediatric medications can lead to discoloration of dental restorations, which affects their durability and longevity. The present in vitro study evaluated the effects of commonly used pediatric medications on the color stability of a conventional and a bulk-fill composite resin. For this study, 80 disc-shaped specimens of each composite were prepared in molds with a diameter of 6 mm and thicknesses of 2 or 4 mm (n = 40 per thickness per material). A spectrophotometer was used toevaluate the baseline color of the specimens in the International Commission on Illumination L*a*b* color space. Each specimen was immersed separately in a container holding 1 of 8 liquid medications (n = 5 per thickness per medication): amoxicillin/clavulanate, clarithromycin, cephalexin, acetaminophen, ibuprofen, levetiracetam, multivitamin, or albuterol. After the container was shaken for 2 minutes, the specimen was removed from the medication and stored in artificial saliva. The cycle was repeated every 8 hours for 1 week. The color measurements were repeated after 1 week of immersion cycles, and the overall color change (82*) was calculated; a value of AE* > 3.3 was considered clinically perceptible. The data were analyzed with 1-way and 2-way analyses of variance as well as the Levene test and Games-Howell post hoc test (P < 0.05). All specimens displayed clinically perceptible color changes after exposure to medications commonly used by children. The mean color change in the 4-mm bulk-fill composite resin group was significantly greater than that in all other groups (P < 0.05). However, there was no significant difference in color change based on the immersion drug for either of the composites (P > 0.05). Thestudy findings show that exposure of composite resin to certain commonly used pediatric drugs causes color changes that are clinically perceptible. [ABSTRACT FROM AUTHOR]

The shielded neutron assay probe (SNAP) neutron detector for passive neutron counting, neutron source strength measurements, and material transmission estimates upgrade has been completed to the benefit of a wide-ranging community of users. This paper details the hardware and software upgrades involved. The total efficiency of the SNAP-IV has been upgraded and characterized for four different measurement configurations, and is described in this paper. The effects of a shift in neutron energy spectrum on the characterized efficiency were studied for a variety of common neutron sources and shown to have a correlation on the subsequent neutron source strength calculations provided to the user. Finally, the approach of using two modes of detector operation is demonstrated to provide an estimate of thickness of an intervening material. [ABSTRACT FROM AUTHOR]

Creasing and folding are fundamental steps in many manufacturing processes of multi-material paperboard packaging. The complex structure of these materials, which comprise layers of cellulose fibres, aluminium, and polyethylene, coupled with the growing complexity of packaging designs, make these process operations essential to ensure the required structural integrity for packaging as well as their functionality in daily life. This paper introduces an approach for modelling damage in paper-based sandwich materials by integrating fibre-based and cohesive numerical modelling techniques. The results prove the effectiveness of the proposed methodology, opening new possibilities for process design and optimization in packaging manufacturing. [ABSTRACT FROM AUTHOR]

This study utilizes Additive Manufacturing (AM), as a key enabler, in creating Polyethylene (PE)-based composites from industrial waste. The benefits of this study are: firstly, promoting environmental sustainability by successfully fabricating composites by repurposing industrial waste and increasing the capacity of PE recycling through AM; and secondly, developing high-value PE-based composites with enhanced structural, mechanical and rheological properties. Detailed printability assessment of various blend ratios of waste PE, Polystyrene, and fiber reinforced resin are discussed and successful printing of PE-based composites with tangible improvements in material properties is demonstrated. The agility of the proposed approach is also highlighted. [ABSTRACT FROM AUTHOR]

The anatomic total shoulder remains the gold standard arthroplasty option for patients with an intact rotator cuff. Avoiding glenoid resurfacing in the form of hemiarthroplasty is known to be less effective than anatomic total shoulder arthroplasty, but glenoid loosening remains the most common reason for revision surgery with anatomic replacement. A thorough understanding of the bony and soft-tissue anatomy—both native and pathologic—is required for optimal placement of the glenoid component. Despite significant research on these topics, there remain many unknowns. We will review the most pertinent evidence available with regard to glenoid component material, design, and placement with the goal of providing clarity in how to best implant glenoid components with revision-free longevity. There is expansive evidence regarding the glenoid implant design and placement, but questions still remain. Following this review, it is recommended to implant an all polyethylene, pegged glenoid component recreating both the native glenoid version and inclination with appropriate soft tissue balance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to investigate the impact of the mucus gel barrier on intestinal mucosal uptake of lipid-based nanocarriers (NCs). Zwitterionic- (ZW), polyglycerol- (PG) and polyethylene glycol- (PEG) surfactant-based o/w nanoemulsions were developed. NCs were assessed regarding their size and zeta potential, stability in biorelevant media and mucus, mucus permeation behavior, cellular interactions and uptake by Caco-2 cells with and without mucus and by a Caco-2/HT29-MTX co-culture. All NCs were in the size range of 178 – 204 nm and exhibited a zeta potential between -4.2 and +1.2 mV. ZW- and PG-NCs demonstrated mucus permeating properties comparable to PEG-NCs. In contrast, ZW- and PG-NCs showed high cellular uptake, whereas limited cellular uptake was observed in case of PEG-NCs. Furthermore, mucus on Caco-2 cells as well as the mucus secreting co-culture had a significant impact on the cellular uptake of all tested NCs. According to these results, ZW- and PG-NCs are advantageous to overcome the mucus and epithelial barrier of the intestinal mucosa. Within this study the impact of mucus on cellular uptake of lipid-based nanocarriers (NCs) with different surface decorations was investigated. The potential of NCs with zwitterionic-, polyglycerol- and polyethylene glycol-surfactants on their surface to overcome the mucus and epithelial barrier was evaluated. Zwitterionic- and polyglycerol-NCs showed mucus permeating properties similar to PEG-NCs. In contrast, zwitterionic- and polyglycerol-NCs substantially outperformed PEG-NCs in their cellular uptake properties. According to these findings, zwitterionic- and polyglycerol-NCs have the potential to overcome both the mucus and epithelial barrier of the mucosa. [Display omitted] [ABSTRACT FROM AUTHOR]

The present study has been undertaken with two objectives, namely developing a laboratory test method to measure the absorbency of absorbent layers and investigating the properties and performance of pearl millet fluff (PMF) as an absorbent web of sanitary napkins using commercially available polypropylene and polyethylene as top and back layer respectively. The results indicate that the burette method, developed to test the absorbency of the absorbent layer of the napkin, is simple, effective, and reproducible. Further, the PM fluff used as an absorbent layer in sanitary napkins is an eco-friendly and economical source for this application. [ABSTRACT FROM AUTHOR]

The aim of our study was to monitor the antiproliferative/cytotoxic and genotoxic effects of both, poly(ethylene glycol)-block-poly(lactic acid) (PEG- b-PLA) and titanium dioxide (TiO2) nanoparticles on the tumor (HT-29, MCF-7, U118MG) and healthy (HEK-293T) cell lines during 2D cultivation and during cultivation in the spheroid form (3D cultivation). Cells or spheroids were cultivated with nanoparticles (0.01, 0.1, 1, 10, 50, and 100 μg/ml) for 72 hours. The cytotoxic effect was determined by the MTT test and the genotoxic effect by the comet assay. We found that 2D cultivation of tumor cell lines with PEG-b-PLA and TiO2 nanoparticles had an anti-proliferative effect on human colon cancer cell line HT-29, human breast cancer cell line MCF-7, human glioma cell line U-118MG during 72h cultivation, but not on control/healthy HEK-293T cells. At the concentrations used, the tested nanoparticles caused no cytotoxic effect on tumor cell lines. Nanoparticles PEG-b-PLA induced significant damage to DNA in HT-29 and MCF-7 cells, while TiO2 nanoparticles in MCF-7 and U-118MG cells. Only PEG-b-PLA nanoparticles caused cytotoxic (IC50 = 7 μg/ml) and genotoxic effects on the healthy cell line HEK-293T after 72h cultivation. The cells which were cultivated in spheroid forms were more sensitive to both types of nanoparticles. After 72h cultivation, we observed the cytotoxic effect on both, the tumor and healthy cell lines. [ABSTRACT FROM AUTHOR]

Sealable polyethylene bags are widely used to protect and store heritage items. While polyethylene is regarded as a stable material, consideration should be given to potential chemical interactions between the polymer and stored objects. The presence of additives used in manufactured polyethylene storage materials should also be considered when they are used in contact with objects. For this study, infrared spectroscopy has been successfully used to identify storage materials and associated additives, as well as to characterise the chemical changes that they undergo. Three case studies are presented that demonstrate that polyethylene bags can undergo chemical changes when exposed to the typical storage conditions used for heritage objects. The storage of degrading cellulose nitrate items shows that polyethylene undergoes oxidation when exposed to the cellulose nitrate degradation products and is identified as detrimental to long term storage viability of the polyethylene. An investigation of the yellow discolouration of polyethylene bags suggests that the oxidation of antioxidant additives, rather than the polyethylene, is responsible for the colour change. It is also demonstrated that polyethylene bags used in a procedure for the consolidation of archaeological ceramics show an interaction between the adhesive solvent employed and the bag additives. [ABSTRACT FROM AUTHOR]

Reverse osmosis (RO) membranes have been widely used in the field of membrane separation. However, most of the commercial RO membranes are fabricated based on a polysulphones- or polyethersulfone-modified polyethylene glycol terephthalate (PET) support, which are thick and exhibit poor solvent resistance. In this study, polyethylene (PE) battery membranes without any hydrophilic modification were directly used to prepare PE-RO membranes. The structures of the products were confirmed via attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The resulting RO membrane prepared with 0.05 wt.% of trimesoyl chloride and 2 wt.% of m-phenylenediamine exhibited a water flux of 12.61 L m−2 h−1 with a desalination (NaCl) rate of 98.6%. The thickness of the PE-RO membrane is 80% of the thickness of the traditional RO membranes and hence has a wider application as a separation membrane. [ABSTRACT FROM AUTHOR]

The elevation of oxidative stress and inflammatory response after injury remains a substantial challenge that can deteriorate the wound microenvironment and compromise the success of wound healing. Herein, the assembly of naturally derived epigallocatechin-3-gallate (EGCG) and Cerium microscale complex (EGCG@Ce) was prepared as reactive oxygen species (ROS) scavenger, which was further loaded in antibacterial hydrogels as wound dressing. EGCG@Ce shows superior antioxidation capacity towards various ROS including free radical, O 2 − and H 2 O 2 through superoxide dismutase-like or catalase-mimicking catalytic activity. Importantly, EGCG@Ce could provide mitochondrial protective effect against oxidative stress damages, reverse the polarization of M1 macrophages and reduce the secretion of pro-inflammatory cytokines. Furtherly, EGCG@Ce was loaded into the PEG-chitosan hydrogel with dynamic, porous, injectable and antibacterial properties as wound dressing, which accelerated the regeneration of both epidermal layer and dermis, resulting in improved healing process of full-thickness skin wounds in vivo. Mechanistically, EGCG@Ce re-shaped the detrimental tissue microenvironment and augmented the pro-reparative response through reducing ROS accumulation, alleviating inflammatory response, enhancing the M2 macrophage polarization and angiogenesis. Collectively, antioxidative and immunomodulatory metal-organic complex-loaded hydrogel is a promising multifunctional dressing for the repair and regeneration of cutaneous wounds without additional drugs, exogenous cytokines, or cells. (1) We reported an effective antioxidant through self-assembly coordination of EGCG and Cerium for managing the inflammatory microenvironment at the wound site, which not only showed high catalytic capacity towards multiple ROS, but also could provide mitochondrial protective effect against oxidative stress damage, reverse the polarization of M1 macrophages and downregulate pro-inflammatory cytokines. EGCG@Ce was further loaded into porous and bactericidal PEG-chitosan (PEG-CS) hydrogel as a versatile wound dressing, which accelerated wound healing and angiogenesis. (2) The applicability of alleviating sustainable inflammation and regulating macrophage polarization through ROS scavenging is a promising strategy for tissue repair and regeneration without additional drugs, cytokines, or cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fractures of the polyethylene post are a rare but known complication after posterior-stabilized (PS) total knee arthroplasty (TKA). We evaluated the polyethylene and patient characteristics for 33 primary PS polyethylene components that were revised with fractured posts. We identified 33 PS inserts revised between 2015 and 2022. Patient characteristics collected included age at index TKA, sex, body mass index, length of implantation (LOI), and patient-reported details on events surrounding the post fracture. Implant characteristics recorded were manufacturer, cross-linking properties (highly cross-linked polyethylene [XLPE] versus ultra-high molecular weight polyethylene [UHMWPE]), wear characteristics based on subjective scoring of the articular surfaces and scanning electron microscopy (SEM) of fracture surfaces. Mean age at index surgery was 55 years (range, 35 to 69), mean body mass index was 29.5 (range, 18.5 to 37.2), and mean LOI was 10.0 (range, 4 to 26). Total surface damage scores were significantly higher in the UHMWPE group versus the XLPE group (57.3 versus 44.2, P =.003). SEM demonstrated fracture initiation at the posterior edge of the post in 10 of 13 cases. UHMWPE fracture surfaces posts had more tufted, irregularly clamshell features, while XLPE posts had more precise clamshell marking and a diamond pattern in the region of acute, final fracture. Characteristics of PS post fracture differed between XLPE and UHMWPE implants, with fractures occurring in the XLPE with less generalized surface damage, after a shorter LOI, and with SEM evaluation indicative of a more brittle fracture pattern. [ABSTRACT FROM AUTHOR]

The use of metal backed glenoid (MBG) components over polyethylene (PE) for total shoulder arthroplasty (TSA) remains controversial. While their advantages and disadvantages are documented, few studies exist demonstrating their efficacy in TSA and conversion rates to a reverse total shoulder arthroplasty (RSA). This study aims to evaluate acute postoperative complications, shoulder pain, functional outcomes, and conversion rates to RSA in patients who underwent TSA using a modular MBG component. A retrospective review of individuals undergoing TSA between October 2014 and March 2019 was performed. Inclusion and exclusion criteria were defined. Baseline surgical characteristics were collected and outcomes were assessed preoperatively and postoperatively using the visual analog scale and American Shoulder and Elbow Surgeons score at preoperative, 1 year, 2 year, and final follow-up. Revision rates were documented. Summary statistics were performed using a two-tailed Student's t-test. The study's final cohort consisted of 91 patients, with a mean age of 66.5 ± 8.1 years, an average body mass index of 32.8 ± 6.9 kg/m2, and 53.8% being male. Majority of patients underwent a TSA on the right side (64.9%), with an average operative duration of 105 minutes and EBL of 148.8 mL. The mean follow-up time was 38.8 months. Thirteen patients (14.3%) went onto conversion to an RSA. Among these individuals, 30.8% (n = 4) was due to a traumatic rotator cuff tear (RCT), 23.1% (n = 3) due to excessive PE wear, and 46.2% (n = 6) due to nontraumatic RCT. The average time to revision for all patients was 27.7 ± 24.8 months. Mean time to revision was 17.5 ± 9.8 months for trauma patients, 51.0 ± 3.5 for patients with signs of excessive PE wear, and 22.9 ± 31.3 months for nontrauma patients. Mean preoperative visual analog scale scores were 6.8 ± 2.3 and American Shoulder and Elbow Surgeons scores were 28.5 ± 15.6. Both significantly improved at 1-year, 2-year, 3-year postoperative timepoints as well as the final postoperative timepoint (P <.001). Patients undergoing TSA using a MBG component reported no acute postoperative complications and improved shoulder function. A small proportion of patients were converted to RSA for signs of a RCT and excessive component wear. This study may suggest that the MBG design demonstrates a failure rate equivalent to cemented PE component systems; thereby, does not expose patients to subsequent higher rates of revision procedures. [ABSTRACT FROM AUTHOR]

The ideal glenoid implant for anatomic total shoulder arthroplasty (aTSA) is one that provides sound fixation and allows ease of conversion to a reverse shoulder arthroplasty should the clinical need arise. This study is the first to report a consecutive series of patients treated with a novel convertible all polyethylene glenoid with hybrid fixation. The aim of the study was to evaluate the clinical, functional, and radiological outcomes of aTSA, for treatment of primary glenohumeral joint osteoarthritis using the SMR TT Hybrid Glenoid. This is a prospective study including consecutive patients from two centers in New Zealand and Sweden. Between August 29, 2017 and April 22, 2020, 103 patients received an aTSA for osteoarthritis with the SMR TT Hybrid Glenoid implant (LimaCorporate, San Daniele del Friuli, Italy). Ninety-seven patients had a minimum follow-up of 24 months and were therefore included in this study. There were 45 female and 52 male patients. The average age at the time of surgery was 68.2 years (range 49-81 years). Preoperative and postoperative clinical evaluations were performed using the American Shoulder and Elbow Surgeons score and the Oxford Shoulder Score. Preoperative and postoperative range of motion measures were conducted using a goniometer. Standardized Grashey and axillary lateral radiographs were utilized to assess for evidence of glenoid and humeral component failure and loosening. The mean follow-up duration was 2.3 years (range 2.0-4.6 years). The mean preoperative and postoperative American Shoulder and Elbow Surgeons scores were 29.0 ± 12.4 and 90.3 ± 14.5, respectively (P <.001). The mean preoperative and postoperative Oxford Shoulder Scores were 21.0 ± 6.7 and 45.3 ± 4.4, respectively (P <.001). We found significant improvements in the range of motion, with mean forward flexion increasing from 87° to 155° and abduction 73° to 149°, respectively. Radiologically, there was no evidence of glenoid or humeral component failure or loosening. Six patients had evidence of reduced bone density around the humeral component. Two patients had repair of traumatic rupture of subscapularis tendon in the early postoperative period. None of the patients had revision of the glenoid or humeral components. Patients treated with an aTSA with the SMR TT Hybrid Glenoid, a novel glenoid implant that has the potential to simplify the process of revision, achieved promising clinical and radiologic results at a minimum of two years. [ABSTRACT FROM AUTHOR]

This article presents the issue of recycling and maintaining the processing properties of materials made of plastics. For this purpose, samples from recycled, low-density, polyethylene were tested. The impact of the use of dyes and surface printing on the lifecycles of material and its quality was examined. For this purpose, an analysis was carried out using differential scanning calorimetry and thermos-gravimetry. It was found that the use of dyes may affect the quality of the material and increase the disposal costs of pre-used materials. [ABSTRACT FROM AUTHOR]

Graphene has local superconductivity, very high electron mobility, good mechanical properties and high stability, and is therefore an excellent filler material for self-sensing cementitious composites. The incorporation of graphene provides a broad application prospect for the development of self-sensing cementitious composites. This work explored the effects of polyethylene (PE) fiber size and surface modifiers on the compressive and tensile properties of ultra-high performance concrete (UHPC). Then, graphene was added on this basis to observe the effect of graphene doping on the electrical properties of UHPC and to select the optimal doping amount. Finally, the mechanical properties and tensile and compressive self-sensing of the UHPC added with graphene were tested. Finally, the bridge with higher stress under self-weight is simulated by finite element to find the location of sensor placement and design a simple bridge health monitoring system. [ABSTRACT FROM AUTHOR]

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We aimed to make comparisons of different bearing surfaces in patients after cementless total hip arthroplasty. The network meta-analysis was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. The primary outcomes were implant survival and Harris hip score (HHS). Secondary outcomes included linear wear rates and serum level of metal ions. Subgroup analyses were performed by: (1) classifying head sizes as small and large; (2) femoral heads as ceramic and metal; and (3) liners as metal, ceramic, polyethylene, highly cross-linked polyethylene (HXP), or vitamin E-infused highly cross-linked polyethylene (HXPE). A total of 64 eligible RCTs with different bearings were assessed. Overall inconsistency and heterogeneity were acceptable. In the 10 years follow-up, metal-on-polythene and ceramic-on-polythene bearings with small heads showed higher risk for revisions compared with metal-on-HXP and ceramic-on-HXP bearings with small heads. Similarly, only metal or ceramic-on-polythene bearings with small heads showed inferiority in HHS compared with other bearings. Conventional polyethylene liners showed higher linear wear rates compared with HXP, HXPE, and ceramic liners at 5 and 10 years after surgery, while metal-on-metal and ceramic-on-metal bearings showed higher serum level of cobalt and chromium. Bearings containing HXP, HXPE, and ceramic liners showed comparable survivorship and hip function at follow-up of 5 and 10 years. Hard-on-hard bearings containing metal had higher serum level of metal ions than others. Bearings containing conventional polyethylene had worse performance in terms of implant survival, hip function, and wear rates. Level I. • Bearings containing HXP, HXPE and ceramic liners showed comparable survivorship and hip function in the mid-term and long-term follow-up. • Hard-on-hard bearings containing metal had higher serum level of metal ions than others. • Bearings containing conventional polyethylene had poor performance in implant survival, hip function and wear rates. [ABSTRACT FROM AUTHOR]

Total shoulder arthroplasty (TSA) provides excellent long-term clinical outcomes in the treatment of glenohumeral arthritis. However, symptomatic glenoid polyethylene loosening can be seen at intermediate follow-up and can lead to shoulder pain and dysfunction. The purpose of this study was to perform a systematic review of the available literature to determine the optimal management of symptomatic glenoid loosening with regard to reoperation and patient satisfaction following various approaches to symptomatic glenoid loosening. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies investigating revision arthroplasty for the treatment of glenoid loosening with clinical outcomes were identified. Clinical failure was defined as a repeat procedure after revision arthroplasty. Overall, 14 studies met inclusion criteria that included 483 patients with a mean age of 66.5 ± 3.0 years who underwent revision arthroplasty for symptomatic glenoid loosening. There were 8 studies that discussed conversion to a hemiarthroplasty (HA, 148 patients), 7 studies that discussed glenoid reimplantation in a single setting (1-stage TSA, 157 patients), 2 studies that discussed glenoid reimplantation in a staged setting (2-stage TSA, 18 patients), and 2 studies that discussed conversion to a reverse shoulder arthroplasty (RSA, 164 patients). All patients underwent glenoid component removal. The length of follow-up was significantly shorter in the RSA group (41 months for RSA vs. 56 months for HA vs. 55 months for 1-stage TSA vs. 62 months for 2-stage TSA, P <.001). The reoperation rate at the final follow-up was 19% for the HA cohort, 20% for the 1-stage TSA cohort, 22% for the 2-stage TSA cohort, and 21% for the RSA cohort (P =.971). Patient satisfaction rate at the final follow-up was 62% for the HA cohort, 66% for the 1-stage TSA cohort, 71% for the 2-stage TSA cohort, and 86% for the RSA cohort (P =.045). Positive cultures were noted in 15% of patients with Cutibacterium acnes comprising 72% of positive cultures. Overall, the optimal management of symptomatic glenoid loosening remains unclear. All 4 types of revision arthroplasty (HA, 1-stage TSA, 2-stage TSA, and RSA) had a similar reoperation rate (20%) at the latest follow-up. Conversion to RSA provided a higher proportion of patients satisfied with the procedure. However, the length of follow-up was significantly shorter than other groups, and therefore longer-term follow-up of this group is needed to determine if results are durable. [ABSTRACT FROM AUTHOR]

Cell–cell fusion involves the fusion of somatic cells into a single hybrid cell. It is not only a physiological process but also an important cell engineering technology which can be applied to various fields, such as regenerative medicine, antibody engineering, genetic engineering, and cancer therapy. There are three major methods of cell fusion: electrical cell fusion, polyethylene glycol (PEG) cell fusion, and virus‐mediated cell fusion. Although PEG cell fusion is the most economical approach and does not require expensive instrumentation, it has a poor fusion rate and induces a high rate of cell cytotoxicity. To improve the fusion rate of the PEG method, we combined it with the pyro‐drive jet injector (PJI). PJI provides instant pressure instead of cell agitation to increase the probability of cell‐to‐cell contact and shorten the distance between cells in the process of cell fusion. Here, we report that this improved fusion method not only decreased cell cytotoxicity during the fusion process, but also increased fusion rate compared with the conventional PEG method. Furthermore, we tested the functionality of cells fused using the PJI‐PEG method and found them to be comparable to those fused using the conventional PEG method in terms of their application for dendritic cell (DC)‐tumor cell fusion vaccine production; in addition, the PJI‐PEG method demonstrated excellent performance in hybridoma cell preparation. Taken together, our data indicate that this method improves cell fusion efficiency as compared to the PEG method and thus has the potential for use in various applications that require cell fusion technology. [ABSTRACT FROM AUTHOR]

Low velocity impact tests were conducted on ultra high molecular weight polyethylene (UHMWPE) laminates having different ply angle. The tests were conducted at various temperatures using steel impactor having 16mm diameter and hemi spherical shape. The selected impact energies are in the range of 50 to 250 Joule. The performance of the composites was compared with respect to peak force, maximum displacement and back face deformation. Results indicated that with increase of temperature, the contact duration increased whereas deceleration was reduced. Various failure mechanisms involved in energy absorption were also addressed. [ABSTRACT FROM AUTHOR]

The presented article describes the method of synthesizing new ionic liquid based on a biguanide cation and a tiocyanate or benzoate anion with antimicrobial properties. The structure of obtained new ionic liquid was confirmed by infrared spectroscopy. Additionally, the article describes a simple method of producing an antibacterial textile materials and PE-based film with the addition of an ionic liquid. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the 24-month clinical performance of composite resin restorations with and without polyethylene fiber in the first permanent molars of pediatric patients with extensive caries. Material and Methods: In total, 75 Class II restorations were placed in the permanent molar teeth of 75 children (mean age 11.3 years) with (FC; n=38) or without (C; n=37) fiber. One operator placed all the restorations. The restorations were evaluated using the modified USPHS criteria in terms of retention, color match, marginal discoloration, anatomic form, marginal adaptation, secondary caries, and postoperative sensitivity. Statistical data were analyzed using chi-square and Cochran tests (p<0.05). Results: At the end of two years, 65 restorations (FC:31; C:34) were followed up. No changes were observed during the first six months. After 24 months of follow-up, there were minor changes in marginal adaptation and marginal color in both groups; however, no statistically significant difference was observed between the clinical performances for all criteria (p>0.05). Conclusion: Extensive composite restorations with or without fibers displayed good clinical performance in high load-bearing areas after 24 months. [ABSTRACT FROM AUTHOR]

The presented article describes the method of synthesizing new ionic liquid based on a biguanide cation and a tiocyanate or benzoate anion with antimicrobial properties. The structure of obtained new ionic liquid was confirmed by infrared spectroscopy. Additionally, the article describes a simple method of producing an antibacterial textile materials and PE-based film with the addition of an ionic liquid. [ABSTRACT FROM AUTHOR]

Usage and functionalization of natural fiber in preparing "wooden-plastic composite (WPC)" is aimed, the research investigates the influence of treatment of "wooden flour" using "carbon nanotube (CNT)", and applying U.V wreathing conditions on wooden flour-polyethylene (WF-PE) WPC. The novelty of this work is the dual functionalization of WF via hydrolysis and reaction with CNT, for better attachment with PE matrix. WF was firstly washed and then treated with CNT to obtain WWF and functionalized WWF-CNT, respectively. Proposed nanocomposites have been prepared using "extrusion" based on polyethylene filled with 50 wt% of wooden fillers (WF, WWF, WF-CNT and WWF-CNT). "Fourier transform infrared (FTIR)" charts and "transmission electron microscope (TEM)" photos indicated the reaction between functionalized CNT and treated fiber through esterification. The findings of "thermal gravimetric analysis (TGA)" indicate more residual ash and higher onset temperature for PE-WWF-CNT and PE-WF, respectively; the thermal stability of all WPCs was also increased after U.V exposure. Furthermore, "dynamic mechanical analysis (DMA)" shows significant improvement in modulus after treatment reaction, and changing in loss factor and thermal transitions. The WWF-CNT-containing WPC achieved higher moduli, even after U.V exposure, due to good interaction between PE matrix and CNT-functionalized fibers, which restricts the molecular mobility. The characterization sentence declares that composite filled with CNT-functionalized fibers is the most stable formula. [ABSTRACT FROM AUTHOR]

The influx of microplastics (MPs) into the Arctic Ocean poses a collective risk, particularly with pronounced sea ice depletion due to global warming. A total of 73 replicate sediment samples were collected at different depths (38 to 79 m) from Chukchi and the Beaufort Seas at 8 stations in the Arctic region during the R/V Mirai cruise (MR22-06C) from August to September 2022. The average concentration of MPs is 79.25 ± 31.08 items/kg d.w. Fibrous MPs of 0–1 mm size range are predominant, with blue being the most prevalent colour. Polymer characterization identified polyethylene (PE) as the predominant polymer. Arctic Ocean regions face heightened health risks from the coexistence of MPs and harmful additives, amplifying concerns over plastic pollution. The alarming surge in MPs within Arctic sediment underscores the urgent need for a proactive, collaborative approach to mitigate this environmental threat and its far-reaching impacts. • Chukchi Sea sediment reveals high levels of microplastic contaminations. • Blue fibrous MP particles are dominant. • Microplastics of the size of 100 μm to 1 mm are high and 4–5 mm are the least recorded. • Polyethylene (PE) and phenol formaldehyde (PF) resin are the predominant polymers. [ABSTRACT FROM AUTHOR]

Micro- and nanoplastics (MNP) have recently received particular attention in freshwater and marine ecosystems, but less is known about their impact on terrestrial species. Ants can be used as biological indicators for many types of pollutants and are therefore a good candidate to explore the effects of MNP pollution. In the present study, we investigated the ability of workers from seven colonies of the acrobat ant Crematogaster scutellaris to detect MNP in their food. After two days of starvation, groups of ten ants were tested for their preference toward control and polyethylene-treated solutions. Every 5 min over a total 20 min period, the number of workers feeding on either solution was counted. The results showed that C. scutellaris workers could detect and avoid contaminated food, feeding more often on the uncontaminated solution in the first 10 min. However, after 10 min the food preference was no longer significant between the groups, likely owing to feeding satiation. We then assessed whether this feeding behaviour is sufficient to cause the accumulation of MNP in the ant. We thereby provided a solution containing fluorescent MNP (fMNP) at the same concentration as in the previous experiments. Observation of the ants' mouthparts using fluorescent light microscopy showed that after 10 min dense aggregations of fMNP were visible. Further investigations are needed to understand the mechanisms of detection of MNP by ants, and the accumulation dynamics in ants' bodies. Moreover, the effects of MNP on the integrity and fitness of ant colonies, as well as the potential transfer across terrestrial trophic chains should be explored. [Display omitted] • The presence of toxic substances is one factor influencing insects' food choice. • Crematogaster scutellaris workers initially avoided polyethylene-treated food at 5 mg l−1. • Ants' preference for the polyethylene-free solution decreased throughout the food choice experiment. • Plastic particles accumulated in ants' mouthparts according to their size during feeding activity. [ABSTRACT FROM AUTHOR]

Physico-chemical properties of microplastics (MPs) change during weathering in the environment. There is a lack of knowledge about the effects of such environmentally relevant MPs on organisms. We investigated: 1) the physico-chemical changes of MPs due to UV–VIS weathering, and 2) compared the effect of pristine and aged MPs on the behaviour of the water flea Daphnia magna and terrestrial crustacean Porcellio scaber. Dry powders of MPs were produced from widely used polymer types: disposable three-layer polypropylene (PP) medical masks (inner, middle and outer), polyester textile fibres, car tires and low-density polyethylene (LDPE) bags and were subjected to accelerated ultraviolet–visible (UV–VIS) ageing. Our results show that the extent of transformation depends on the type of polymer, with PP showing the most changes, followed by LDPE, textile fibres and tire particles. Obvious fragmentation was observed in PP and textile fibres. In the case of PP, but not polyester textile fibres, changes in FTIR spectra and surface properties were observed. Tire particles and LDPE did not change in size, but clear changes were observed in their FTIR spectra. Most MPs, aged and pristine, did not affect the swimming of daphnids. The only effect observed was a significant increase in path length and swimming speed for the pristine tire particles when the recording was done with particles remaining in the wells. After transfer to a clean medium, this effect was no longer present, suggesting a physical rather than chemical effect. Similarly, woodlice showed no significant avoidance response to the MPs tested, although there was a noticeable trend to avoid soils contaminated with pristine polyester textile fibers and preference towards the soils contaminated with aged MP of the middle mask layer. Overall, the apparent changes in physico-chemical properties of MPs after accelerated ageing were not reflected in their effects on woodlice and daphnids. [Display omitted] • PP MPs undergo the most significant physico-chemical changes after UV–VIS aging. • PP, and polyester textile fibres fragment to smaller particles. • Significant chemical changes in FTIR spectra are found for PP, tire particles, and LDPE. • Most MPs, except for pristine tire particles, do not affect the swimming of daphnids. • Only pristine textile fibers and aged middle mask MPs change the behaviour of woodlice. [ABSTRACT FROM AUTHOR]

Low-density polyethylene (LDPE) is extensively used worldwide in various applications due to its versatile features and abundant commercial availability. This study investigated, for the first time, the beneficial use of a novel chemically modified commercial-grade LDPE as a sorbent for oil-water separation in industrial wastewater treatment. Several laboratory tests were conducted in batch and continuous fixed-bed modes to evaluate the LDPE adsorbent's capacity, performance repeatability and recyclability under relevant field conditions. These results were compared to walnut shell (WS), a widely used sorbent for removing oil from industrial wastewaters, including produced water from oil and gas operations. Untreated LDPE achieved higher total organic carbon (TOC) removals and retention capacities, ∼20 % and ∼66 mg/g, respectively, when compared to untreated WS, <5 % and <1 mg/g, respectively. Improved kinetics and adsorption behavior favorability were achieved for LDPE after chemical modification using a cationic monomer. Both the chemically treated LDPE and WS showed comparable TOC removal rates (ranging from 60 % to 80 %). However, the modified LDPE exhibited higher sorption capacities (∼61 mg/g) compared to the treated WS (8.0 mg/g). Chemical regeneration of LDPE with toluene demonstrated superior performance recovery (>90 %) when compared to physical cleaning with deionized water (<40 %). The study presented promising results in advancing novel materials like LDPE to support circular economy in industrial wastewater treatment. [Display omitted] • Low density polyethylene (LDPE) surface was modified for industrial water treatment. • LDPE performance was compared to commercial walnut shell (WS) media. • Oil removal efficiency of LDPE was enhanced after modification (from 20 % to 60 %). • LDPE showed higher sorption capacity than WS media (∼8.0 vs ∼61 mg/g). • Chemical regeneration of LDPE was more effective than physical cleaning. [ABSTRACT FROM AUTHOR]

Three quarters of all plastics produced each year are discarded to landfill after a single use without proper waste management practices, causing a global environmental crisis: waste plastics suffocating our world at enormously large volumes. Discarding plastics into landfill, inefficiently processing them to lower value materials, or incinerating them cause an irreversible loss of the stored energy in plastics. These plastics, however, represent a tremendous resource for the production of chemicals and can be upcycled into high-quality value-added refinery feedstock that could be used to produce virgin polyolefins. In this article, we review pyrolysis and hydrogenolysis based chemical transformations to convert waste polyolefins into liquid hydrocarbons with a special emphasis on life cycle assessment (LCA), reactor technologies, and integration to existing refineries. Several patented technologies are described in detail to shed a light on engineering aspects of the chemical recycling. Liquid products obtained from chemical recycling are examined from the circularity point of view. Feedstock and stream locations in existing refineries and around steam crackers are recommended to feed and/or blend the products obtained from chemical recycling of polyolefins. Challenges, perspectives, and emerging areas of research and engineering are mentioned. [Display omitted] [ABSTRACT FROM AUTHOR]

Two burrowing clam species, namely Meretrix meretrix and Paphia undulata , were offered two sizes (small: 45–53 μm, and large: 106–125 μm) of fluorescent red polyethylene microbeads, and the ingestion (number of MPs in the body tissue and faeces) and rejection (number of MPs in pseudofaeces) of MPs investigated. Overall, MP beads ingested were 36 % more than those rejected. There was also a significant interaction between the size and fate of MPs. For both species, significantly more small beads were ingested than rejected, but there was no difference for the large beads. P. undulata ingested more MPs than M. meretrix and both species could depurate all the ingested MPs in 72 h, although a longer time was needed for the former species. The results can provide guidance on seafood selection and pre-treatment to minimize the number of MPs ingested by humans. • MP beads being ingested were 36 % more than those being rejected. • P. undulata ingested significantly more MPs than M. meretrix. • Significant interaction occurred between the size and fate of MPs, with smaller beads tended to be ingested. • Both species could depurate all the ingested MPs in 72 h. • The clams collected from the wild or aquaculture farms are recommended to depurate in clean seawater for 1–2 days. [ABSTRACT FROM AUTHOR]

This study investigated the spatio-temporal variability of microplastics (MPs) in the sediments of the River Thames (UK) catchment over 30 months (July 2019 – Dec 2021). The average MP concentration was 61 items kg−1 d.w., with fragments <1 mm being dominant and polyethylene (PE) the most common polymer. Adjacent land use influenced MP concentrations and types, with industrial sites showing particularly high levels and a prevalence of small beads and industrial polymers. MP concentrations generally decreased after higher winter flows, likely due to sediment rearrangement or winnowing. This study describes the seasonal concentrations and characteristics of MPs present in sediment from the River Thames catchment, and attempts to identify their likely origin. Further, the study provides new insights into the mobility and fate of MPs in riverine settings under varying flow conditions, which is vital given the predicted increases in flooding under various global heating scenarios. [Display omitted] • Microplastics were pervasive across the catchment; • Microplastic concentrations generally decreased under high flows; • Land use determined microplastic abundance, shape, size and composition. [ABSTRACT FROM AUTHOR]