ABSTRACT
Nanoplastics (NPs, <1 µm) are of great concern worldwide because of their high potential risk toward organisms in aquatic systems, while very little work has been focused on their tissue-specific toxicokinetics due to the limitations of NP quantification for such a purpose. In this study, NPs with two different sizes (86 and 185 nm) were doped with palladium (Pd) to accurately determine the uptake and depuration kinetics in various tissues (intestine, stomach, liver, gill, and muscle) of tilapia (Oreochromis niloticus) in water, and subsequently, the corresponding toxic effects in the intestine were explored. Our results revealed uptake and depuration constants of 2.70-378 L kg-1 day-1 and 0.138-0.407 day-1 for NPs in tilapia for the first time, and the NPs in tissues were found to be highly dependent on the particle size. The intestine exhibited the greatest relative accumulation of both sizes of NPs; the smaller NPs caused more severe damage than the larger NPs to the intestinal mucosal layer, while the larger NPs induced a greater impact on microbiota composition. The findings of this work explicitly indicate the size-dependent toxicokinetics and intestinal toxicity pathways of NPs, providing new insights into the ecological effects of NPs on aquatic organisms.
Subject(s)
Cichlids , Tilapia , Water Pollutants, Chemical , Animals , Tilapia/metabolism , Cichlids/metabolism , Microplastics , Intestines , Liver/metabolism , Water Pollutants, Chemical/metabolismABSTRACT
There is a growing concern about the effects of nanoplastics on biological safety and human health because of their global ubiquity in the environment. Methodologies for quantitative analysis of nanoplastics are important for the critical evaluation of their possible risks. Herein, a sensitive yet simple and environmentally friendly extraction approach mediated by protein corona is developed and coupled to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) for nanoplastic determination in environmental waters. The developed methodology involved the formation of protein corona by addition of bovine serum albumin (BSA) to samples and protein precipitation via salting out. Then, the resulting extract was directly introduced to Py-GC/MS for nanoplastic mass quantification. Taking 50 nm polystyrene (PS) particles as a model, the highest extraction efficiency for nanoplastics was achieved under the extraction conditions of BSA concentration of 20 mg/L, equilibration time of 5 min, pH 3.0, 10% (w/v) NaCl, incubation temperature of 80 °C, and incubation period of 15 min. The extraction was confirmed to be mediated by the protein corona by transmission electron microscopy (TEM) analysis of the extracted nanoplastics. In total, 1.92 and 2.82 µg/L PS nanoplastics were detected in river water and the influent of wastewater treatment plant (WWTP), respectively. Furthermore, the feasibility of the present methodology was demonstrated by applying to extract PS and poly(methyl methacrylate) (PMMA) nanoplastics from real waters with recoveries of 72.1-98.9% at 14.2-50.4 µg/L spiked levels. Consequently, our method has provided new insights and possibilities for the investigation of nanoplastic pollution and its risk assessment in the environment.
Subject(s)
Protein Corona , Water Pollutants, Chemical , Gas Chromatography-Mass Spectrometry , Humans , Microplastics , Polystyrenes/analysis , Pyrolysis , Water Pollutants, Chemical/analysisABSTRACT
Micro- and nanoplastics unavoidably enter into organisms and humans as a result of widespread exposures through drinking waters, foods, and even inhalation. However, owing to the limited availability of quantitative analytical methods, the effect of nanoplastics inside animal bodies is poorly understood. Herein, we report a sensitive and robust method to determine the chemical composition, mass concentration, and size distribution of nanoplastics in biological matrices. This breakthrough is based on a novel procedure including alkaline digestion and protein precipitation to extract nanoplastics from tissues of aquatic animals, followed by quantitative analysis with pyrolysis gas chromatography-mass spectrometry. The optimized procedure exhibited good reproducibility and high sensitivity with the respective detection limits of 0.03 µg/g for polystyrene (PS) nanoplastics and 0.09 µg/g poly(methyl methacrylate) (PMMA) nanoplastics. This method also preserved the original morphology and size of nanoplastics. Furthermore, to demonstrate the feasibility of the proposed method, 14 species of aquatic animals were collected, and PS nanoplastics in a concentration range of 0.093-0.785 µg/g were detected in three of these animals. Recovery rates of 73.0-89.1% were further obtained for PS and PMMA nanospheres when they were spiked into the tissues of Zebra snail and Corbicula fluminea at levels of 1.84-2.12 µg/g. Consequently, this method provides a powerful tool for tracking nanoplastics in animals.
Subject(s)
Polystyrenes , Water Pollutants, Chemical , Animals , Microplastics , Polymethyl Methacrylate , Reproducibility of Results , Water Pollutants, Chemical/analysisABSTRACT
Fog, frost, ice, and other natural phenomena can inevitably affect human life and the function of equipment. Therefore, removal or prevention is an urgent problem to be solved. As a new type of 2D material, graphene possesses great application potential in defogging and antiicing. In this work, a graphene film with intentionally increased defects and uniformly distributed wrinkles is synthesized on copper-zinc alloy substrates by chemical vapor deposition, and transparent electrothermal film defoggers are prepared based on such material. The defoggers can completely remove fog within 5 s when supplying a safe voltage of 28 V. The surface resistance of the defoggers is sensitive to humidity and it can monitor the defogging process in real time. Such outstanding performance is attributed to the ultrafast evaporation mechanism, which can prevent excessive water accumulation. The antiicing performance of wrinkled graphene (WG) is further studied. The antiicing coatings can delay freezing for 1.25 h at -15 °C or 2.8 h at -10 °C. The superior performance of WG can be explained by its unique surface structure and nanoscale roughness. Taken together, WG is expected to be used in antifog glass, rearview mirror defogging, aircraft surface deicing, and other applications.
ABSTRACT
Portable humidity sensors with ultrafast responses fabricated in wearable devices have promising application prospects in disease diagnostics, health status monitoring, and personal healthcare data collecting. However, prolonged exposures to high-humidity environments usually cause device degradation or failure due to excessive water adsorbed on the sensor surface. In the present work, a graphene film based humidity sensor with a hydrophobic surface and uniformly distributed ring-like wrinkles is designed and fabricated that exhibits excellent performance in breath sensing. The wrinkled morphology of the graphene sensor is able to effectively prevent the aggregation of water microdroplets and thus maximize the evaporation rate. The as-fabricated sensor responds to and recovers from humidity in 12.5 ms, the fastest response of humidity sensors reported so far, yet in a very stable manner. The sensor is fabricated into a mask and successfully applied to monitoring sudden changes in respiratory rate and depth, such as breathing disorder or arrest, as well as subtle changes in humidity level caused by talking, cough and skin evaporation. The sensor can potentially enable long-term daily monitoring of breath and skin evaporation with its ultrafast response and high sensitivity, as well as excellent stability in high-humidity environments.
Subject(s)
Graphite/chemistry , Water/analysis , Humidity , Water/chemistry , Wearable Electronic DevicesABSTRACT
Rechargeable aqueous zinc-ion batteries (RAZIBs) offer low cost, high energy density, and safety but struggle with anode corrosion and dendrite formation. Gel polymer electrolytes (GPEs) with both high mechanical properties and excellent electrochemical properties are a powerful tool to aid the practical application of RAZIBs. In this work, guided by a machine learning (ML) model constructed based on experimental data, polyacrylamide (PAM) with a highly entangled structure was chosen to prepare GPEs for obtaining high-performance RAZIBs. By controlling the swelling degree of the PAM, the obtained GPEs effectively suppressed the growth of Zn dendrites and alleviated the corrosion of Zn metal caused by water molecules, thus improving the cycling lifespan of the Zn anode. These results indicate that using ML models based on experimental data can effectively help screen battery materials, while highly entangled PAMs are excellent GPEs capable of balancing mechanical and electrochemical properties.
ABSTRACT
Previous research suggests that self-compassion is associated with mental health and well-being. However, little has been done to understand the role of self-compassion in the family context. Hence, the present study investigated the associations between parents' self-compassion, parent's depressive symptoms, and child adjustment. A total 189 Chinese parents (101 mothers) whose children were 2-8 years old were recruited to complete a questionnaire, including measures of parents' self-compassion, depressive symptoms, and children's prosocial behavior, internalizing problems, and externalizing problems. Findings indicated mediation effects, in that parents' depressive symptoms mediated the association between their self-compassion and child adjustment outcomes, namely children's internalizing and externalizing problems, after controlling for the effects of monthly family income, child gender, and parent gender. Competing hypothesis suggested that parents' self-compassion did not moderate between parents' depressive symptoms and child adjustment outcomes. Hence, the association between parental depressive symptoms and child adjustment was not dependent on the level of parents' self-compassion. As an implication, researchers and practitioners should be made aware of the benefits of parents' self-compassion on parents' mental health and child adjustment.
Subject(s)
Depression , Self-Compassion , Child , Child, Preschool , Depression/epidemiology , Depression/psychology , Female , Humans , Mental Health , Mothers/psychology , Parent-Child Relations , Surveys and QuestionnairesABSTRACT
A new unsymmetric small-molecule acceptor (SMA) BTPOSe-4F was designed by unsymmetric structure modification to Y6 with an alkyl upper side chain replaced by an alkoxy side chain and a sulfur atom in its central fused ring replaced by a selenium atom, for the application as an acceptor to fabricate organic solar cells (OSCs). BTPOSe-4F exhibits a higher lowest unoccupied molecular orbital (LUMO) energy level, a reduced nonradiation energy loss, and better charge extraction properties in its binary OSCs with a higher Voc of 0.886. Furthermore, the ternary OSCs with the addition of PC71BM demonstrated a higher power conversion efficiency (PCE) of 17.33% with Voc of 0.890 V. This work reveals that the unsymmetric modification strategy can further give impetus to the photovoltaic performance promotion of OSCs for Y6-series SMAs.
ABSTRACT
With the wide applications of terahertz (THz) devices in future communication technology, THz protection materials are essential to overcome potential threats. Recently, THz metamaterials (MMs) based on two-dimensional (2D) materials (e.g., graphene, MXenes) have been extensively investigated due to their unique THz response properties. In this review, THz protection theories are briefly presented first, including reflection loss and shielding mechanisms. Then, the research progress of graphene and other 2D material-based THz MMs and intrinsic materials are reviewed. MMs absorbers in the forms of single layer, multiple layers, hybrid and tunable metasurfaces show excellent THz absorbing performance. These studies provide a sufficient theoretical and practical basis for THz protection, and superior properties promised the wide application prospects of 2D MMs. Three-dimensional intrinsic THz absorbing materials based on porous and ordered 2D materials also show exceptional THz protection performance and effectively integrate the advantages of intrinsic properties and the structural characteristics of 2D materials. These special structures can optimize the surface impedance matching and enable multiple THz scatterings and electric transmission loss, which can realize high-efficiency absorption loss and active controllable protection performance in ultra-wide THz wavebands. Finally, the advantages and existing problems of current THz protection materials are summarized, and their possible future development and applications are prospected.
ABSTRACT
BACKGROUND: Insomnia as one of the dominant diseases of traditional Chinese medicine (TCM) has been extensively studied in recent years. To explore the novel approaches of research on TCM diagnosis and treatment, this paper presents a strategy for the research of insomnia based on machine learning. METHODS: First of all, 654 insomnia cases have been collected from an experienced doctor of TCM as sample data. Secondly, in the light of the characteristics of TCM diagnosis and treatment, the contents of research samples have been divided into four parts: the basic information, the four diagnostic methods, the treatment based on syndrome differentiation and the main prescription. And then, these four parts have been analyzed by three analysis methods, including frequency analysis, association rules and hierarchical cluster analysis. Finally, a comprehensive study of the whole four parts has been conducted by random forest. RESULTS: Researches of the above four parts revealed some essential connections. Simultaneously, based on the algorithm model established by the random forest, the accuracy of predicting the main prescription by the combinations of the four diagnostic methods and the treatment based on syndrome differentiation was 0.85. Furthermore, having been extracted features through applying the random forest, the syndrome differentiation of five zang-organs was proven to be the most significant parameter of the TCM diagnosis and treatment. CONCLUSIONS: The results indicate that the machine learning methods are worthy of being adopted to study the dominant diseases of TCM for exploring the crucial rules of the diagnosis and treatment.
ABSTRACT
In this work, an easy, low-cost, and widely applicable method was developed to improve the compatibility between the ceramic fillers and the polymer matrix by adding 3-aminopropyltriethoxysilane (KH550) as a coupling agent during the fabrication process of BaTiO3-P(VDF-CTFE) nanocomposites through solution casting. Results show that the use of KH550 can modify the surface of ceramic nanofillers; therefore, good wettability on the ceramic-polymer interface was achieved, and the enhanced energy storage performances were obtained by a suitable amount of the coupling agent. This method can be used to prepare flexible composites, which is highly desirable for the production of high-performance film capacitors. If an excessive amount of coupling agent is used in the process, the non-attached coupling agent can participate in complex reactions, which leads to a decrease in dielectric constant and an increase in dielectric loss.
Subject(s)
Electricity , Nanocomposites/chemistry , Polymers/chemistry , Barium Compounds , Nanocomposites/ultrastructure , Surface Properties , TitaniumABSTRACT
Selective laser melting (SLM) is known to generate large and anisotropic residual stresses in the samples. Accurate measurement of residual stresses on SLM-produced samples is essential for understanding the residual stress build-up mechanism during SLM, while a dramatic fluctuation can be observed in the residual stress values reported in the literature. On the basis of studying the influence of surface roughness on residual stress measured using X-ray diffraction (XRD), we propose a procedure coupling XRD technique with pretreatment consisting of mechanical polishing and chemical etching. The results highlight that residual stresses measured using XRD on as-built SLM-produced samples with high surface roughness are significantly lower than those measured on samples with finished surface, which is due to the stress relaxation on the spiked surface of as-built samples. Surface distribution of residual stresses and the effect of scanning strategy were systematically investigated for SLM-produced AlSi10Mg samples. Microstructural morphology was observed at the interface between sample and building platform and was linked to the surface distribution of residual stresses. This procedure can help us accurately measure the residual stresses in SLM-produced samples and thus better understand its build-up mechanism during the SLM process.
ABSTRACT
In the present work, we have introduced a series of stable radical-doped coordination compounds composed of donor-acceptor structures and shown to produce organic radicals in situ as a result of unconventional lone pair-π interactions in ambient conditions. Inconspicuous lone pair-π and C-Hπ interactions were shown to play a key role in self-assembly as well as the charge transfer process, resulting in a long-lived charge-separated state able to generate organic radicals. The resultant species displayed broad-spectrum antimicrobial activity, including against multi-drug-resistant bacteria. This study unveiled the promise of reactive organic radical-doped materials as a new platform for developing antimicrobial agents that can overcome antibiotic resistance.
Subject(s)
Anti-Bacterial Agents/chemistry , Free Radicals/chemistry , Metal-Organic Frameworks/chemistry , Naphthalimides/chemistry , Anti-Bacterial Agents/pharmacology , Bacillus subtilis , Drug Resistance, Multiple, Bacterial , Escherichia coli , Metal-Organic Frameworks/pharmacology , Microbial Sensitivity Tests , Pseudomonas aeruginosa , Semiconductors , Staphylococcus aureus , Structure-Activity RelationshipABSTRACT
Two Pd(II) complexes based on tetradentate chelate ligands with either a 1,2,4-triazolyl (Pd1) or 1,2,3-triazolyl (Pd2) unit were synthesized, and their structure-property relationships were studied. Both Pd1 and Pd2 are rare bright deep blue Pd(II) phosphors with contrasting properties. Pd1 displays stimuli-responsive luminescence in response to UV irradiation, concentration, or temperature change, which is ascribed to the facile switching of monomer to excimer emission. In contrast, a similar stimuli-responsive luminescence was not observed for Pd2. Crystal structures and time-dependent density functional theory computational studies established that the excimer formation of Pd1 is caused by electronically favored intermolecular π-π interactions and less steric protection of the Pd core because of the position of its alkyl chains, compared to Pd2. In solution, the excimer emission of Pd1 shows a much greater sensitivity toward oxygen than the monomer emission with a very large Stern-Volmer constant ( Ksv) that is more than twice that of the monomer emission. Both Pd(II) complexes are found to be outstanding oxygen sensors in ethyl cellulose films with superior sensitivity ( Ksvapp = 0.228-0.346 Torr-1) over their Pt(II) equivalents ( Ksvapp = 0.00674-0.0110 Torr-1), owing to their long phosphorescence decay lifetimes. Furthermore, Pd1 shows an excellent photostability, compared to the Pt(II) analogue, making it one of the best and highly robust oxygen sensors based on cyclometalated metal complexes.
ABSTRACT
Porcine-derived xenogeneic sources for transplantation are a promising alternative strategy for providing organs for treatment of end-stage organ failure in human patients because of the shortage of human donor organs. The recently developed blastocyst or pluripotent stem cell (PSC) complementation strategy opens a new route for regenerating allogenic organs in miniature pigs. Since the eye is a complicated organ with highly specialized constituent tissues derived from different primordial cell lineages, the development of an intact eye from allogenic cells is a challenging task. Here, combining somatic cell nuclear transfer technology (SCNT) and an anophthalmic pig model (MITFL247S/L247S), allogenic retinal pigmented epithelium cells (RPEs) were retrieved from an E60 chimeric fetus using blastocyst complementation. Furthermore, all structures were successfully regenerated in the intact eye from the injected donor blastomeres. These results clearly demonstrate that not only differentiated functional somatic cells but also a disabled organ with highly specialized constituent tissues can be generated from exogenous blastomeres when delivered to pig embryos with an empty organ niche. This system may also provide novel insights into ocular organogenesis.