Plastic Stability Research Articles

Forget to Learn (F2L): Circumventing plasticity–stability trade-off in continuous unsupervised domain adaptation

In continuous unsupervised domain adaptation (CUDA), deep learning models struggle with the stability-plasticity trade-off—where the model must forget old knowledge to acquire new one. This paper introduces the “Forget to Learn” (F2L), a novel framework that circumvents such a trade-off. In contrast to state-of-the-art methods that aim to balance the two conflicting objectives, stability and plasticity, F2L utilizes active forgetting and knowledge distillation to circumvent the conflict’s root causes. In F2L, dual-encoders are trained, where the first encoder – the ‘Specialist’ – is designed to actively forget, thereby boosting adaptability (i.e., plasticity) and generating high-accuracy pseudo labels on the new domains. Such pseudo labels are then used to transfer/accumulate the specialist knowledge to the second encoder—the ‘Generalist’ through conflict-free knowledge distillation. Empirical and ablation studies confirmed F2L’s superiority on different datasets and against different SOTAs. Furthermore, F2L minimizes the need for hyperparameter tuning, enhances computational and sample efficiency, and excels in problems with long domain sequences—key advantages for practical systems constrained by hardware limitations.

The Flammability and Thermal Stability of Filling Epoxy Foam Plastics for Construction Purposes.

An effective type of polymer heat-insulating material (foams) based on reactive oligomers is casting epoxy foams with high technological and operational parameters. However, polyepoxide foams are highly flammable, which significantly restrains their application in the construction industry. The aim of this work was to develop effective methods for reducing the flammability of filling epoxy foams. In order to achieve the objective, the following objectives were addressed: determining the influence of the chemical nature and content of additive and reactive bromine- and phosphorus-containing compounds on the thermal stability, flammability and operational properties of filling epoxy foams, and the development of polyepoxy foams of reduced flammability with high-quality physical and mechanical characteristics. When estimating the flammability of epoxy foams, we used both state-approved methods and the methods described in scientific and technical literature. The thermal properties of epoxy foams were studied with the help of multimodular thermoanalytical complex DuPont-9900. The data on the influence of the apparent density of foams and oxygen concentration in the oxidant flow on the flame propagation speed on the horizontal surface of polyepoxy foams are presented. It was revealed that the chemical nature of amine hardeners does not affect the thermal stability and flammability of epoxy foams. It was established that phosphate plasticizers are ineffective flame retardants of foamed epoxy resin, and the chemical structure of additive organobromic flame retardants insignificantly affects their efficiency. It was shown that microencapsulated flame retardants are inferior in flame retardant efficiency to additive flame retardants. It was found that effective flame retardants for casting polyepoxy foams are phosphorus-containing oligoether methacrylate and epoxidized waste from the production of tetrabromodiphenylpropane. The results of this research will form the basis for the production of an experimental industrial batch of samples of pouring epoxy foams of reduced flammability.

Complete conversion of eucalyptus wood to dynamic covalent networks: An in-situ plasticising strategy

Ongoing innovation in bio-based plastics aims to meet more economical and diverse societal needs. However, the dependence on a single biomass source and the generally inadequate wet stability and moisture mechanical properties of traditional bio-based plastics severely limit their competitiveness. We have developed a high mechanical performance, fully bio-based, thermoset in-suit plastic from an almost worthless agricultural and forestry waste (eucalyptus) through a simple and environmentally friendly deconstruction-reconstruction strategy. In this process, the hydrogen and covalent bonds in the lignin and cellulose of eucalyptus are broken and then reorganised through dynamic covalent bonds. The resulting eucalyptus-based plastic exhibits high mechanical strength, excellent water resistance, UV ageing resistance, photothermal performance and light/heat controllable shape memory properties. By preserving the original structure of the lignin and cellulose, its natural degradability is ensured. This strategy for developing full-component plastics from solid agricultural and forestry waste offers a new approach to producing more competitive fully bio-based plastics.

Translucent zirconia dental prosthesis processed by Direct Ink Writing: Updates and challenges

Direct ink writing (DIW) is an extrusion-based additive manufacturing technique, which uses a layer-by-layer deposition of an ink, usually containing high solid loads and low concentration of additives, to provide plasticity and structural stability for the construction of near-net-shaped pieces. In this work, a zirconia stabilized with 5 mol% Y2O3 colloidal ink was developed aiming to obtain dense prototypes, partially translucent, with potential for making dental prostheses. Cylindrical pieces (Ø 20 mm × 2.5 mm), prismatic bars (55 × 5 × 4 mm) and 3-element dental prostheses were printed based on Computer-aided design (CAD) models, using a printing speed of 10 mm.s−1 and a nozzle with Ø 0.25 mm. The printed samples were dried at strictly controlled conditions, debinded using an optimized thermal cycle, and sintered at 1600 °C-2 h. The sintered parts were characterized by X-ray diffraction, scanning electron microscopy, Vickers hardness, fracture toughness and bending strength. Concerning dental prosthesis, a post-processing finishing strategy was performed on pre-sintered bodies to highlight the anatomical details. After sintering, samples presented relative density around 94–95 %, Vickers hardness, fracture toughness and Young Modulus of 12.7 ± 0.3GPa, 5.31 ± 0.21 MPa.m1/2 and 195.4 ± 45 GPa, respectively. A characteristic strength (σ0) of 303 MPa was attained, which is above the requirements for its application as ceramic single-unit dental prostheses. A critical analysis of the technological difficulties of this 3D printing technique for manufacturing dental prostheses is presented, while future directions are addressed.

The Influence of Microstructure and Process Design on the Plastic Stability of 4 wt% Medium‐Manganese Steels

The influence of different microstructures on the plastic stability of an air‐hardened industrially produced medium‐manganese steel is presented. For this matter, heat treatment parameters before and during intercritical annealing (IA) are varied, to achieve different microstructures. The resulting duplex microstructure is consecutively tested by tensile tests, which are monitored by digital image correlation (DIC) to obtain information on the local plastic deformation. The tests are accompanied by microstructure investigations using optical, scanning electron, and transmission electron microscopy. Finally, X‐ray and electron backscatter diffraction experiments are performed before and after deformation, to describe the altering phase fractions. It is demonstrated that the effect of the deformation temperature prior to IA treatment has a significant influence on the duplex microstructure, as it changes the austenite morphology from lamellar to globular and increases the phase fraction. The change in austenite phase fraction and morphology results in a higher yield strength (≈100 MPa), as well as higher uniform and total elongations (+2% and +5%, respectively). The DIC and tensile tests reveal that these differences in the austenite phase lead to a complete change in the strain hardening behavior, from continuous flow to discontinuous serrated flow, with clearly visible deformation bands during plastic deformation.

RNA binding tunes the conformational plasticity and intradomain stability of TDP-43 tandem RNA recognition motifs

TAR DNA binding protein 43 (TDP-43) is a nuclear RNA/DNA-binding protein with pivotal roles in RNA-related processes such as splicing, transcription, transport, and stability. The high binding affinity and specificity of TDP-43 toward its cognate RNA sequences (GU-rich) is mediated by highly conserved residues in its tandem RNA recognition motif (RRM) domains (aa: 104–263). Importantly, the loss of RNA binding to the tandem RRMs caused by physiological stressors and chemical modifications promotes cytoplasmic mislocalization and pathological aggregation of TDP-43. Despite the substantial implications of RNA binding in TDP-43 function and pathology, its precise effects on the intradomain stability, and conformational dynamics of the tandem RRMs is not properly understood. Here, we employed all-atom molecular dynamics (MD) simulations to assess the effect of RNA binding on the conformational landscape and intradomain stability of TDP-43 tandem RRMs. RNA limits the overall conformational space of the tandem RRMs and promotes intradomain stability through a combination of specific base stacking interactions and transient electrostatic interactions. In contrast, tandem RRMs exhibit a high intrinsic conformational plasticity in the absence of RNA, which, surprisingly, is accompanied by a tendency of RRM1 to adopt partially unfolded conformations. Overall, our simulations reveal how RNA binding dynamically tunes the structural and conformational landscape of TDP-43 tandem RRMs, contributing to physiological function and mitigating pathological aggregation.

Ionized copolyesters with pH-responsive degradability: Accelerated degradation in specific environments

The development of environmentally responsive biodegradable polymers is a promising solution for balancing the stability and degradability of biodegradable plastics. In this study, a commercial biodegradable polyester, poly(butylene adipate-co-butylene terephthalate) (PBAT), was used as the substrate and was synthetically modified with a small amount of anionic sodium 1–3-isophthalate-5-sulfonate (SIPA) to obtain the ionized random poly(butylene adipate-co-butylene terephthalate-co-butylene 5-sodiosulfoisophthalate) (PBATS). The introduction of the sodium sulfonate ionic group enhanced the mechanical and heat-resistant properties of the material, while significantly improving the hydrophilicity and water absorption of the copolyesters of PBATSs and endowing them with special pH-responsive degradation properties. Compared with PBAT, PBATS copolyesters could accelerate degradation in acidic or alkaline buffer solutions and natural seawater, while degradation was inhibited in neutral buffer solutions at pH 7.2. Degradation experiments in simulated gastric, intestinal, and body fluids revealed that the copolyester showed specific and rapid degradation in acidic gastric fluids. This environmentally-responsive degradable material greatly expands the special applications of biodegradable polyesters in the fields of environmental remediation and medical applications.

Performance stability of plastics for neutron-gamma pulse shape discrimination

The introduction of the first commercially available plastic scintillators with pulse shape discrimination (PSD) offered by Eljen Technology marked progress towards potentially replacing liquid scintillators in neutron detection. However, use of these plastics over several recent years has revealed an important flaw in these materials: the eventual degradation of scintillation light output and PSD performance. Studies described in this paper considered possible reasons for this degradation. Experiments conducted with numerous lab-prepared and commercial EJ-276 samples showed that the main factor affecting the instability is oxidation that involves highly reactive radicals generated during the polymerization process or from the further breakdown of polymer chains under oxygen/air exposure. Based on the obtained results, the stability of scintillation performance for PPO (2,5-Diphenyloxazole)-based PSD plastics has been improved through modifications of the composition via the utilization of scintillation dyes and compounds with antioxidant properties that diminish the effects of oxidation. Elements of these studies were used in the commercial production of the most recent EJ-276D PSD plastic version for fast neutron detection and 6Li-loaded plastics for thermal neutron and antineutrino detection applications. Performance projections of the new PSD plastics indicate a likely degradation of less than 10 % over 5–10 years in comparison to previous EJ-276 that might lose up to 30–40 % of the scintillation light during 1–2 years of storage or deployment under ambient conditions.

Organic Ionic Plastic Crystal/Polymer Composite Electrolyte Prepared By Solution Casting Method for Solid-State Lithium Batteries

Solid-state electrolytes have been considered as a promising candidate to address the safety issues for next-generation lithium batteries. Organic ionic plastic crystals (OIPCs) are attracting increasing interests as solid electrolyte materials due to their unique advantages, such as plasticity, nonflammability, good thermal and electrochemical stability. In this study, an OIPC-based composite electrolyte consisting of the OIPC 1-ethyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (Pyr12TFSI), lithium bis(trifluoromethylsulfonyl)imide (LiTFSI) and the polymer polyvinylidene fluoride (PVDF) has been developed by a facile solution casting strategy. A free-standing and flexible OIPC/polymer composite membrane was fabricated by the solution casting method, which not only provides flexibility and better electrode/electrolyte contact, but also is more compatible with current battery processing methods. The composite membrane used in Li/Li symmetric cell was cycled stably over 900 h at a current density of 0.1 mA cm−2 at 50 °C, demonstrating that the OIPC/polymer composite electrolyte enabled the reversible and stable lithium plating and stripping behaviors. Further tests of the OIPC/polymer composite as solid electrolyte in LiFePO4/Li cell presented a high specific capacity of 149 mAh g−1 at 0.1 C and a long cycle life of over 440 cycles with capacity retention of 89% at 0.5 C at 50 °C, which showed improved rate capability and cycling stability in comparison with the composites with similar compositions but obtained by powder pressing method. This study demonstrated the potential of the OIPC/polymer composite solid electrolyte prepared by solution casting method and will promote the development of high-performance OIPC-based composite electrolytes for solid-state batteries.

Clonal plasticity and trait stability may facilitate knotweed invasion in Europe

Abstract Invasive plant species pose significant ecological and economic threats due to their establishment and dominance in non-native ranges. Previous studies have yielded mixed results regarding the plants' adaptive mechanisms for thriving in new environments, and particularly, little is known about how the phenotypic plasticity of growth and defense-related traits may facilitate plant invasion. This study addressed these uncertainties by employing the aggressive weed Reynoutria japonica as a study model. We examined the differences in growth, defense-related traits, and biomass allocation between R. japonica populations from native and introduced ranges grown in two common gardens with distinct climate conditions. Our results demonstrated that while the introduced populations did not exhibit increases in height and total dry mass, nor reductions in leaf defense levels, their investment in leaf production was significantly higher compared to the native populations. Additionally, introduced populations displayed greater phenotypic plasticity in clonal ramet but less phenotypic plasticity in biomass production than native populations across varying environments. These findings highlight the roles of phenotypic plasticity and specific trait adaptations, such as clonality, in the successful invasion of R. japonica. This study has important implications for managing invasive plant species under changing environmental conditions.

Photocatalytic Cracking of non-Biodegradable Plastics to Chemicals and Fuels.

Plastic pollution is worsening the living conditions on Earth, primarily due to the toxicity and stability of non-biodegradable plastics (NBPs). Photocatalytic cracking of NBPs is emerging as a promising way to cleave inert C-C bonds and abstract the carbon atoms from these wastes into valuable chemicals and fuels. However, controlling these processes is a huge challenge, ascribed to the complicated reactions of various NBPs. Herein, we summarize recent advances in the CO2 and carbon-radical-mediated photocatalytic cracking of NBPs, with an emphasis on the pivotal intermediates. The CO2-mediated cracking proceeded with indiscriminate C-H/C-C bond cleavage of NBPs and tandem photoreduction of CO2, while carbon-radical-mediated cracking was realized by the prior activation of C-H bonds for selective C-C bond cleavage of NBPs. Catalytic generation and conversion of different intermediates greatly depend on the kinds of active species and the structure of photocatalysts under irradiation. Meanwhile, the fate of a specific intermediate is compared with small molecule activation to reveal the key problems in the cracking of NBPs. Finally, the challenges and potential directions are discussed to improve the overall efficiency in the photocatalytic cracking of NBPs.

Experimental study on the dynamic properties of soft clay with sand interlayers under cyclic loading

Unlike uniform soils, soft clays with sand interlayers in coastal soft clays, can affect their mechanical properties, potentially impacting underground-construction safety and stability. Consolidated undrained cyclic triaxial tests were conducted to study the dynamic properties and deformation behavior of clay, focusing on how the thickness ratio between the sand and clay layers and the cyclic-stress ratio influence the pore pressure, axial strain, shear-modulus ratio, and normalized damping ratio. The results indicate that higher thickness ratios and cyclic-stress ratios lead to a faster decay of the shear-modulus ratio, quicker increases in pore pressure, faster strain accumulation, and fewer cycles to failure. The normalized damping ratio has three different forms: decreasing, decreasing then increasing, and increasing. However, at a cyclic-stress ratio of 0.2 and thickness ratio of 0.25, the samples exhibit better dynamic characteristics. Soft clay with sand layers exhibits characteristics in line with the stability theory. At low thickness and cyclic-stress ratios, purely elastic and elastically stable phases are observed. As the thickness and cyclic-stress ratios increase, it transitions to plastic stability and incremental failure.

The Effect of Fuel Quality on Cavitation Phenomena in Common-Rail Diesel Injector—A Numerical Study

Plastic is one of the most widely used materials worldwide. The problem with plastic arises when it becomes waste, which needs to be treated. One option is to transform plastic waste into synthetic fuels, which can be used as replacements or additives for conventional fossil fuels and can contribute to more sustainable plastic waste treatment compared with landfilling and other traditional waste management processes. Thermal and catalytic pyrolysis are common processes in which synthetic fuels can be produced from plastic waste. The properties of pyrolytic oil are similar to those of fossil fuels, but different additives and plastic stabilizers can affect the quality of these synthetic fuels. The quality of fuels and the permissible particle sizes and number density are regulated by fuel standards. Particle size in fuels is also regulated by fuel filters in vehicles, which are usually designed to capture particles larger than 4 μm. Problems can arise with the number density (quantity) of particles in synthetic fuels compared to that in fossil fuels. The present work is a numerical study of how particle size and number density (quantity) influence cavitation phenomena and cavitation erosion (abrasion) in common-rail diesel injectors. The results provide more information on whether pyrolysis oil (synthetic fuel) from plastic waste can be used as a substitute for fossil fuels and whether their use can contribute to more sustainable plastic waste treatments. The results indicate that the particle size and number density slightly influence cavitation phenomena in diesel injectors and significantly influence abrasion.

Microstructure and mechanical properties evolution of 310S and GH3536 in hydrogen metallurgy service

The evolution of microstructure and mechanical properties of 310S austenitic stainless steel and GH3536 nickel-based alloy in hydrogen metallurgy service condition is investigated by conducting heat treatment under high temperature and hydrogen atmosphere. As the annealing time increases at 750 °C, carbide precipitate phases of the σ and μ brittle phases appear in the materials. At 900 °C, the dissolution of carbides induces the dispersion of brittle phases, while the hydrogen content reaching its peak. These brittle phases are still present at defects like grain boundaries at 1050 °C, with the surface of precipitates showing corrosion pits. Materials exhibit increasing strength and hardness initially with temperature and annealing time, followed by a decrease. Meanwhile, fracture elongation shows a positive correlation with temperature but a negative correlation with time. After annealing at 1050 °C for 500 h, GH3536 retains its high-temperature softening behavior and elongation at fracture, demonstrating excellent plastic stability. Furthermore, the mechanism of high temperature and hydrogen affecting metals is expounded, providing reference for the selection and optimization of materials which service in high temperature and hydrogen.

Beyond Immune Balance: The Pivotal Role of Decidual Regulatory T Cells in Unexplained Recurrent Spontaneous Abortion.

Recurrent spontaneous abortion (RSA) is defined as two or more consecutive pregnancy failures, which brings tremendous stress to women of childbearing age and seriously affects family well-being. However, the reason in about 50% of cases remains unknown and is defined as unexplained recurrent spontaneous abortion (URSA). The immunological perspective in URSA has attracted widespread attention in recent years. The embryo is regarded as a semi-allogeneic graft to the mother. A successful pregnancy requires transition to an immune environment conducive to embryo survival at the maternal-fetal interface. As an important member of regulatory immunity, regulatory T (Treg) cells play a key role in regulating immune tolerance at the maternal-fetal interface. This review will focus on the phenotypic plasticity and lineage stability of Treg cells to illustrate its relationship with URSA.

Enhanced Plastic Stability: Achieving High Performance in a Al6xxx Alloy Fabricated by Additive Manufacturing.

Additive manufacturing (AM) facilitates the creation of materials with unique microstructural features and distinctive phenomena as compared to conventional manufacturing methods. Among the various well-fabricated AM alloys, aluminum alloys garner substantial attention due to their extensive applications in the automotive and aerospace industries. In this work, an Al6xxx alloy is successfully fabricated with outstanding performance. A nucleation agent is introduced to diminish the susceptibility to cracking during the AM process, thereby inducing a heterogeneous microstructure in this alloy. However, the introduction of ultrafine grains induces plastic instability, evidenced by the presence of Lüders band. This work investigates the evolution of the Lüders band and the strategy to reduce their undesirable effect. The heterogeneity destabilizes the band propagation and thus deteriorates the ductility. Through a T6 heat treatment, the local Lüders strain decreases from 10.0% to 6.2%, leading to a substantial enhancement in plastic stability. With the increase in grain growth and the enlargement of coarse grain regions, the mismatch between the local and macroscopic Lüders strain disappears. Importantly, the strength and the thermal conductivity are concurrently increased. The findings demonstrate the significance of ensuring plastic stability to achieve improved strength-ductility trade-off in AM alloys with heterogeneous microstructures.

Study on the effect of stress path on the deformation and non-coaxial characteristics of modified iron tailings

In order to study the deformation and non-coaxial characteristics of fiber cement modified iron tailing sand (FCIT) under different stress paths. The evolution law of the dynamic stress ratio (η) on the cumulative deformation and non-coaxial angle of FCIT under different tension-compression amplitude ratios (α) was explored through hollow torsional shear tests. The deformation behavior of FCIT is analyzed by using the stability theory. The research results show that: 1) The increase of dynamic stress level will deepen the cumulative deformation of FCIT, while the increase of α will make the deformation mode of FCIT develop into bulging failure-shear failure-tensile failure. 2) According to the development trend of cumulative strain and cumulative strain rate of FCIT, it can be divided into three stages: plastic stability, plastic creep and incremental collapse, and the cumulative strain rate development prediction model is established, and the prediction error distribution is within ±20%. 3) The stress path determines the non-coaxiality of FCIT to a certain extent, and the non-coaxial angle fluctuates and decreases with the increase of the principal stress direction angle. When α=0.125, the maximum and minimum values of the non-coaxial angle of FCIT are 1.5 rad and 0.4 rad respectively. 4) Cement hydration reaction generates calcium alumina and hydrated calcium silicate (C-S-H) to make FCIT structure more compact, fiber-matrix interfacial connections more dense, and play a role in filling the pores.

Investigating the Relationship between Cadmium Exposure and the Risk of Prostate Cancer: A Systematic Review and Dose-Response Meta-Analysis.

Cadmium, a toxic heavy metal, experienced a surge in production during the 20th century due to the rise of nickel-cadmium batteries, metal plating, and plastic stabilizers. Exposure to cadmium primarily occurs through the consumption of contaminated food, such as vegetables and grains, as well as drinking water or inhaling polluted air. The objective of this study was to investigate the relationship between cadmium exposure and the incidence of prostate cancer using a systematic review and meta-analysis approach. This research involved searching and retrieving observational and experimental studies conducted until May 2022 from various databases, including ISI Web of Science, Cochrane, Science Direct, Scopus, Pub-Med, and Google Scholar. Data analysis was performed using Stata 15 statistical software. The initial search yielded 794 articles, which were subsequently reduced to 427 articles after eliminating duplicates. Following the application of inclusion and exclusion criteria, a total of 16 studies were included in the meta-analysis. The odds ratio of prostate cancer compared to the first quartile of exposure in the second quartile was 1.03 (0.95-1.12), in the third quartile it was 1.12 (0.99-1.26) and in the fourth quartile of exposure was equal to 1.16 (0.79-1.70). Regarding the investigation of the probability of the occurrence of publication bias, the results of Begg's and Egger's tests were not statistically significant. Although exposure to cadmium leads to an increase in the chance of prostate cancer, this chance increase was not statistically significant.

Influence of colourants on environmental degradation of plastic litter

Plastic degradation and the resultant production of microplastics has an important effect on the environment and fauna across the world. This paper shows that the colourant incorporated into plastic formulations has a significant effect on the stability of plastics. A static experimental exposure of differently coloured polypropylene bottle tops from the same manufacturer to a moderate climate over 3 years showed that black, white and silver plastics were almost unaffected whereas the specific blue, green and especially red pigments used in this study were significantly degraded. The second part of the study collected littered HDPE plastic containers from a remote South African beach and analysed their condition as a function of the given manufacturing date stamp. Most items were black or white and samples up to 45 years old were found with relatively little environmental degradation other than mild abrasion. It appears that carbon and titanium dioxide colourants protect the HDPE polymer from photolytic degradation. While anthraquinone, phthalocyanine and diketopyrrolopyrrole pigments were found to enable UV light to degrade the polymer leading to brittle plastics, promoting the formation of microplastics, it is likely that other pigments that do not strongly absorb in the UV will result in similar degradation.

Neurotoxicity of Benzotriazole Ultraviolet Stabilizers in Teleost Fishes: A Review.

Plastic additives that maintain integrity have been extensively studied for potential toxicity to fish; however, chemicals that protect polymers from (artificial) UV degradation are less studied. Benzotriazole UV stabilizers (BUVSs) are the most widely used UV stabilizers in plastics and are often used in sunscreens, cosmetics, paint, and food packaging. BUVSs can negatively affect aquatic wildlife when released into the environment via plastic degradation. In this review, we summarize the distribution of BUVSs globally and discuss neurotoxicological endpoints measured in fish to understand how these plastic additives can affect the neurological health of teleost fishes. BUVSs have been detected in aquatic environments at concentrations ranging from 0.05 up to 99,200 ng/L. Studies show that BUVSs affect behavioral responses and acetylcholinesterase activity, indicators of neurotoxicity. Our computational analysis using transcriptome data suggests certain pathways associated with neurodegeneration are responsive to exposure to BUVSs, like "Complement Activation in Alzheimer's Disease". Based on our review, we identify some research needs for future investigations: (1) molecular studies in the central nervous system to define precise mechanisms of neurotoxicity; (2) a wider range of tests for assessing aberrant behaviors given that BUVSs can affect the activity of larval zebrafish; and (3) histopathology of the nervous system to accompany biochemical analyses. These data are expected to enhance understanding of the neurotoxicity potential of benzotriazoles and other plastic additives.