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•TK/TD behavior in mice is MPs particle size-dependent.•Mice-based TK parameters and threshold criteria could be derived.•Assist in designing robust researches to evaluate human MP ...consumption.
While a large body of literature has shown that microplastics (MPs) are highly likely to be accumulated in marine organisms and terrestrial animals, information about toxicity of MPs in mammal from a mechanistic point of view is more limited. Our paper fills this knowledge gap by assessing polystyrene (PS)-MPs-mice system based on toxicity-based toxicokinetic/toxicodynamic (TBTK/TD) modeling to quantify organ-bioaccumulation and biomarker responses appraised with published dataset. The key TBTK-parameters for mice liver, kidney, and gut posed by 5 or 20 μm PS-MPs could be obtained. We found that gut had the highest bioaccumulation factor (BCF) of ∼8 exposed to 5 μm PS-MPs with a mean residence time of ∼17 days. We showed that threshold concentrations of 5 and 20 μm PS-MPs among the most sensitive biomarkers were 8 ± 5 (mean ± SE) and 0.71 ± 0.14 μg g−1 bw, respectively, implicating that particle size was likely to affect TK/TD behavior in mice. The mice-based TK parameters and threshold criteria greatly assist in designing robust researches to evaluate MP consumption by humans. We establish a TBTK/TD framework for mechanistically assessing potential from mice size-specific MPs exposure that would offer a tool-kit for extrapolating to humans from health risk assessment perspective.
A novel approach for using conjugated rod–coil materials as a floating gate in the fabrication of nonvolatile photonic transistor memory devices, consisting of n‐type Sol‐PDI and p‐type C10‐DNTT, is ...presented. Sol‐PDI and C10‐DNTT are used as dual functions of charge‐trapping (conjugated rod) and tunneling (insulating coil), while n‐type BPE‐PDI and p‐type DNTT are employed as the corresponding transporting layers. By using the same conjugated rod in the memory layer and transporting channel with a self‐assembled structure, both n‐type and p‐type memory devices exhibit a fast response, a high current contrast between “Photo‐On” and “Electrical‐Off” bistable states over 105, and an extremely low programing driving force of 0.1 V. The fabricated photon‐driven memory devices exhibit a quick response to different wavelengths of light and a broadband light response that highlight their promising potential for light‐recorder and synaptic device applications.
High‐performance photonic transistor memory devices are fabricated using conjugated rod–coil materials as a photoactive floating gate, in which the conjugated rods and side‐chain coils act as charge‐trapping and tunneling moieties, respectively. By inheriting their self‐assembled structure, both n‐type and p‐type memory devices exhibit a fast response, a current contrast over 105, and an extremely low programing driving force of 0.1 V.
Donor–acceptor type polymers and supramolecules are promising electrets in photonic field‐effect transistor (FET)‐type memory because of their diversified polymer‐structure design and favorable ...mechanical tolerance. Using intermolecular association, supramolecule electrets can surpass donor–acceptor type polymers with versatile facile combining processes. Currently, there has been no application of charge‐transfer (CT) supramolecules in electrets of photonic FET memory devices. Herein, a novel series of CT‐based supramolecular electrets comprising poly(1‐pyrenemethyl methacrylate) (PPyMA) and 7,7,8,8‐tetracyanoquinodimethane (TCNQ) is used to elucidate the effect of CT on photonic FET memory. Accordingly, memory devices based on the supramolecular electret with an equimolar content of pyrene and TCNQ exhibit superior bistable memory switchability using electrical/photoprograming with UV (365 nm) and green light (525 nm). This shows a broad memory window of 34 V and favorable memory ratio of over 106 after 104 s. The memory performance can be attributed to the favorable molecular association and dispersion between pyrene and TCNQ in the solid state. The results provide evidence that CT‐based supramolecular electrets warrant applications in optoelectronic applications.
A series of charge transfer‐based supramolecular electrets comprising poly(1‐pyrenemethyl methacrylate) and 7,7,8,8‐tetracyanoquinodimethane are applied to elucidate the effect of charge transfer on photonic field‐effect transistor memory. Accordingly, the devices based on the supramolecular electret exhibit superior memory switchability using electrical/photoprograming under UV (365 nm) and green light, showing a broad memory window of 34 V and memory ratio of over 106 after 104 s.
•Toxicokinetic (TK) data of microplastics (MPs) and nanoplastics (NPs) are compiled.•TK properties and mechanisms of MPs and NPs are thoroughly discussed.•Several conceptual PBTK model structures are ...proposed for MPs and NPs in mammals.•Challenges and implication of PBTK modeling for MPs and NPs are discussed.
Microplastics (MPs) and nanoplastics (NPs) pollution has emerged as a significant and widespread environmental issue. Humans are inevitably exposed to MPs and NPs via ingestion, inhalation, and dermal contacts from various sources. However, mechanistic knowledge of their distribution, interaction, and potency in the body is still lacking. To address this knowledge gap, we have undertaken the task of elucidating the toxicokinetic (TK) behaviors of MPs and NPs, aiming to provide mechanistic information for constructing a conceptual physiologically based toxicokinetic (PBTK) model to support in silico modeling approaches. Our effort involved a thorough examination of the existing literature and data collation on the presence of MPs in the human body and in vitro/ex vivo/in vivo biodistribution across various cells and tissues. By comprehending the absorption, distribution, metabolism, and excretion mechanisms of MPs and NPs in relation to their physicochemical attributes, we established a foundational understanding of the link between external exposure and internal tissue dosimetry. We observed that particle size and surface chemistry have been thoroughly explored in previous experimental studies. However, certain attributes, such as polymer type, shape, and biofilm/biocorona, warrant attention and further examination. We discussed the fundamental disparities in TK properties of MPs/NPs from those of engineered nanoparticles. We proposed a preliminary PBTK framework with several possible modeling approaches and discussed existing challenges for further investigation. Overall, this article provides a comprehensive compilation of existing TK data of MPs/NPs, a critical overview of TK processes and mechanisms, and proposes potential PBTK modeling approaches, particularly regarding their applicability to the human system, and outlines future perspectives for developing PBTK models and their integration into human health risk assessment of MPs and NPs.
Carbosilane side chain-equipped isoindigo–bithiophene semiconducting polymers (PII2T) have been designed and synthesized for stretchable electronics applications. Systematically tailoring the length ...and branch position of carbosilane side chains (C6 to C10) offers an effective route to optimize charge-transport behavior and improve the mechanical properties of semiconducting polymer thin films. The basic polymer properties, surface morphology, electrical characteristics, and strain-dependent performance of polymers with various lengths of carbosilane side chains were explored. The series of polymers exhibited a field-effect mobility over 2 cm2 V–1 s–1, and an odd–even effect was observed relating to the length of side chains. On the other hand, when the longer side chain was incorporated, a lower thin-film modulus was reached because the extended side chain can dilute the volume of the rigid polymer backbone and open up the space between polymer chains (i.e., larger lamellar spacing). Surprisingly, PII2T-C10 thin films possess desirable electrical and mechanical properties, achieving a mobility of 1 cm2 V–1 s–1 even when stretched under 100% strain, which is the best electrical performance among intrinsically stretchable conjugated polymers in the research community.
Recent research interest in organic field‐effect transistor (FET) memory has shifted to the functionality of photoprogramming in terms of its potential uses in multibit data storage and ...light‐assisted encryption and its low‐energy consumption and broad response to various optical bands. Phototransistor memory can be modulated through both electrical stress and light illumination, allowing it to function as an orthogonal operation method without mutual interference. Herein, the basic design concepts, requirements, and architectures of phototransistor memory are introduced. Design architectures such as channel‐only, channel‐with‐photogate, photochromatic channel devices and floating gate, photoactive polymer, and organic molecule‐based electrets are systematically categorized. The operational mechanism and impact of effective combinations of channels and electrets are reviewed to provide a fundamental understanding of photoprogramming as well as its potential future developmental applications as nonvolatile memory. Furthermore, recent advances in phototransistors and their diverse applications, including nonvolatile memory, artificial synapses, and photodetectors, are summarized. Finally, the outlook for the future development of phototransistors is briefly discussed. A comprehensive picture of the recent progress in phototransistors is provided.
Herein, the basic design concepts and architectures of phototransistors are introduced. Design strategies involving channel‐only and channel‐with‐photogate devices as well as devices using floating gate, photoactive polymer, and organic molecule electrets are systematically categorized. Recent advances in phototransistors and their diverse applications: nonvolatile memory, artificial synapses, and photodetectors, are summarized. This review sheds light on the future development of phototransistors.
Poly(butyl acrylate) (PBA) side chain equipped isoindigo-bithiophene (II2T) conjugated polymers have been designed and synthesized for stretchable electronic applications. The PBA segment possesses ...low glass transition temperature and high softness, offering a great opportunity to improve the mechanical property of semiconducting polymer thin films that typically contain lots of rigid conjugated rings. Polymers with 0, 5, 10, 20 and 100% of PBA side chains, named PII2T, PII2T-PBA5, PII2T-PBA10, PII2T-PBA20, and PII2T-PBA100, were explored, and their polymer properties, surface morphology, electrical characteristics, and strain-dependent performance were investigated systematically. The series polymers showed a charge carrier mobility of 0.06–0.8 cm2 V–1 s–1 with an on/off current ratio over 105 dependent on different amounts of PBA chains as probed using a top-contact transistor device. Moreover, we can still achieve a mobility higher than 0.2 cm2 V–1 s–1 even if 10% of PBA side chains were added (i.e., PII2T-PBA10). Such PII2T-PBA polymers, more attractive, exhibited superior thin film ductility with a low tensile modulus down to 0.12 GPa (PII2T-PBA20) due to the soft PBA side chain. The more PBA segment was incroporated, the lower modulus was reached. The mobility performance, at the same time, remained approximately 0.08 cm2 V–1 s–1 based on PII2T-PBA10 films even under a 60% strain and could be simultaneously operated over 400 stretching/releasing cycles without significant electrical degradations. The above results suggest that the rational design of soft PBA side chains provides a great potential for next-generation soft and wearable electronic applications.
The present study introduced Ren'py software as a digital storytelling (DST) tool to explore the effective use of digital game design learning in promoting critical thinking among high school ...students. A sample of 46 high school students enrolled in “Thinking Utopia,” an elective course in critical thinking for civics education, was put into groups of 3 to 4 for learning activities towards their collaborative designs of DST games. The course stretched across 9 weeks. Students' performance in critical thinking tests was also closely examined using paired‐sample t‐test analysis, which found no significant improvements; however, their interview responses were carefully studied using qualitative analysis and revealed that many of them agreed that the proposed collaborative activities for game script writing and for their collaborative designs of original hurdle questions have stimulated their critical thinking ability and contributed to the development of their other skills such as communication, problem‐solving and media literacy.
Lay Description
What is already known about this topic
• Critical thinking is a key 21st century skill for students to arrive at an impartial judgement on controversial issues.
• Digital storytelling and its practical value as an emerging technology may contribute to students' ability in critical thinking.
• Collaboration and teamwork for design‐based learning may help students achieve deep learning.
What this paper adds
• A model course plan on civics education featuring collaborative learning through digital game‐based design.
• Further discussions on students' ability in critical thinking and their learning experience in a course involving collaborative design of digital storytelling games.
Implications for practice and/or policy
• Collaborative learning through digital storytelling game‐based design may not promote critical thinking among high school students if they failed to initiate active discussions among themselves.
• Collaborative learning through digital storytelling game‐based design among high school students may benefit other aspects of their learning, such as their skills in communication, problem‐solving, media literacy and test taking.
Thus far, there is still no study systematically investigating the influence of asymmetric side-chain design on a polymer’s stretchability and its associated stretchable device applications. Herein, ...three kinds of asymmetric side chains consisting of carbosilane side chain (Si-C8), siloxane-terminated side chain (SiO-C8), and decyltetradecane side chain (DT) are engineered in isoindigo-bithiophene (PII2T, P1–P3) and isoindigo-difluorobithiophene (PII2TF, P4–P6) conjugated polymers, and their structure–stretchability correlation is explored in field-effect transistor characterization. It is revealed that owing to the geometric difference between the side chains, different asymmetric side-chain combinations impose distinct influences on the molecular stacking and orientation of the derived polymers. Surprisingly, the combination of asymmetric side chains and backbone fluorination is shown to deliver the best stretchability and mechanical durability of the derived polymer. Consequently, P6 consisting of asymmetric Si-C8/DT side chains and fluorinated backbone possesses the best mobility preservation of 81% at 100% strain with the stretching force perpendicular to the charge-transporting direction. Moreover, it presents 90% mobility retention after 400 stretching–releasing cycles with 60% strain, greatly exceeding the value (36%) of the non-fluorinated counterpart (P3). Our results suggest that the rational design of asymmetric side chains and backbone fluorination provides an efficient way to enhance the intrinsic stretchability of conjugated polymers.
Conjugated polymers synthesized through random terpolymerization have recently attracted great research interest due to the synergetic effect on the polymer’s crystallinity and semiconducting ...properties. Several studies have demonstrated the efficacy of random terpolymerization in fine-tuning the aggregation behavior and optoelectronic property of conjugated polymers to yield enhanced device performance. However, as an influential approach of backbone engineering, its efficacy in modulating the mobility–stretchability property of high-performance conjugated polymers has not been fuller explored to date. Herein, a series of random terpolymers based on the diketopyrrolopyrrole-bithiophene (DPP-2T) backbone incorporating different amounts of isoindigo (IID) unit are synthesized, and their structure–mobility–stretchability correlation is thoroughly investigated. Our results reveal that random terpolymers containing a low IID content (DPP95 and DPP90) show enhanced interchain packing and solid-state aggregation to result in improved charge-transporting performance (can reach 4 order higher) compared to the parent polymer DPP100. In addition, owing to the enriched amorphous feature, DPP95 and DPP90 deliver an improved orthogonal mobility (μh) of >0.01 cm2 V–1 s–1 under a 100% strain, higher than the value (∼0.002 cm2 V–1 s–1) of DPP100. Moreover, DPP95 even yields 20% enhanced orthogonal μh retention after 800 stretching–releasing cycles with 60% strain. As concluded from a series of analyses, the improved mobility–stretchability property exerted by random terpolymerization arises from the enriched amorphous feature and enhanced aggregation behavior imposed by the geometry mismatch between different acceptors (DPP and IID). This study demonstrates that backbone engineering through rational random terpolymerization not only enhances the mobility–stretchability of a conjugated polymer but also realizes a better mechanical endurance, providing a new perspective for the design of high-performance stretchable conjugated polymers.
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