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2D transition metal dichalcogenides have been studied extensively in the field of electronics and photonics. Among them, the molybdenum chalcogenides have been receiving considerable attention due to their potential usage in field‐effect transistors and biosensors. Despite such promising aspects of these materials, studies regarding temperature effects on MoSe remain relatively rare. Herein, MoxSey (x = 0 ≈ 10, y = 0 ≈ 2) thin films are fabricated by radio frequency (RF) magnetron cosputtering on silicon and investigated using scanning electron microscopy for various atomic ratios and annealing temperatures from room temperature to 500 °C. Above the melting point of Se, Se evaporates and forms a layer, subsequently leading Mo to be exposed on the surface of the thin films. From the X‐ray diffraction and X‐ray photoelectron spectroscopy results, silicon peaks are observed due to the evaporation of Se. In addition, both Mo and Se are oxidized at above 300 °C. The work functions of the MoxSey thin films show the highest value at 200 °C measured by ultraviolet photoelectron spectroscopy and a Kelvin probe. Above the melting point of Se, there is a tendency for the work function to decrease due to the influence of Mo. [ABSTRACT FROM AUTHOR]

Migrants' workplace experiences in their host society, including failure, shape their social adjustment, yet how migrants learn from failures is under-investigated. The study presented here examined how North Korean migrants struggling for a foothold in South Korea sought to learn from failures in their workplaces and everyday life. The article draws on nine months of ethnographic research in South Korean restaurants and cafés employing North Korean migrants. Data sources include informal conversations and loosely structured interviews with five purposefully selected women who started, or planned to start, their own enterprise. The findings reveal that these migrants perceived failure in five interrelated spheres: financial, relational, physical, psychological and professional. Participants developed perspectives to understand failure as an integral part of learning in a new society and adopting unfamiliar role expectations and responsibilities. They also applied knowledge they had acquired through their failures to change their approach to their career and to strengthen their personal and business capacity to obtain a legitimate social position. Paradoxically, failures that were beyond their control, such as legal problems, created opportunities to receive practical support from, and increase trust in, South Koreans. In addition to challenging the discourse that portrays North Korean migrants as deficient, these findings contribute to adult education scholarship on migrants' situated learning in their host societies. [ABSTRACT FROM AUTHOR]

While the various physicochemical properties of engineered nanomaterials influence their toxicities, their understanding is still incomplete. A predictive framework is required to develop safe nanomaterials, and a Bayesian network (BN) model based on adverse outcome pathway (AOP) can be utilized for this purpose. In this study, to explore the applicability of the AOP-based BN model in the development of safe nanomaterials, a comparative study was conducted on the change in the probability of toxicity pathways in response to changes in the dimensions and surface functionalization of multi-walled carbon nanotubes (MWCNTs). Based on the results of our previous study, we developed an AOP leading to cell death, and the experimental results were collected in human liver cells (HepG2) and bronchial epithelium cells (Beas-2B). The BN model was trained on these data to identify probabilistic causal relationships between key events. The results indicated that dimensions were the main influencing factor for lung cells, whereas -OH or -COOH surface functionalization and aspect ratio were the main influencing factors for liver cells. Endoplasmic reticulum stress was found to be a more sensitive pathway for dimensional changes, and oxidative stress was a more sensitive pathway for surface functionalization. Overall, our results suggest that the AOP-based BN model can be used to provide a scientific basis for the development of safe nanomaterials. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the underlying mechanism of multi-walled carbon nanotubes (MWCNT) induced cellular response and their potential cross-talk, specifically, between endoplasmic reticulum (ER) stress, MAPK activation and apoptosis and how these nano-bio interactions depend on the physico-chemical properties of MWCNT. For this purpose, human bronchial epithelial (Beas2B) and human hepatoma (HepG2) cell lines, were exposed to five kinds of MWCNTs which differ in functionalization and aspect ratios. Tissue-specific sensitivity was evident for calcium homeostasis, ER-stress response, MAPK activation and apoptosis, which further depended on surface functionalization as well as aspect ratios of MWCNT. By applying specific pharmaceutical inhibitors, relevant biomarkers gene and proteins expressions, we found that possibly MWCNT induce activation of IRE1a-XPB1 pathway- mediated ER-stress response, which in turn trigger apoptosis through JNK activation in both type of cells but with variable intensity. The information presented here would have relevance in better understanding of MWCNT toxicity and their safer applications. [ABSTRACT FROM AUTHOR]

Drawing on critical theory for adult education, the authors of this article examine the Academic Credit Bank System (ACBS), an open educational system operating in the Republic of Korea since 1998. It was designed to provide both traditional-age and mature students with opportunities to earn academic qualifications, including Bachelor's degrees, at low cost and in collaboration with the traditional system. In a literature review, the authors analyse the system with reference to the underlying ideology (i.e., credentialism, an emphasis on formal credentials) and hegemonic (dominant) characteristics (i.e., the foci of formal education and the educational norms created by the government-centred administrative system) in which ACBS operates, particularly in the context of lifelong learning. The authors investigate why an ACBS degree is still not considered to be equivalent to a traditional degree in the job market. Their data are drawn from the domestic and international literature relating to ACBS, including policy reports which tend to offer only descriptions of ACBS without subjecting the educational system itself to even small-scale analysis. The authors found that ACBS is limited primarily with regard to social recognition and that this systemic limitation is an outcome of Korea's academic credentialism. In particular, they argue that a non-formal learning domain cannot be successful unless the credentials it produces are perceived as comparable to those from the dominant (i.e., traditional) system of higher education. Overall, this study advances the education field's understanding of ACBS by using a critical lens to unveil tensions in practice and identify problems at the ground level, which cannot be identified merely through statistical evaluation. The authors conclude this article with a suggestion of in-depth, qualitative examinations and critical reflection on ACBS. [ABSTRACT FROM AUTHOR]

Although ecotoxicological and toxicological risk assessments are performed separately from each other, recent efforts have been made in both disciplines to reduce animal testing and develop predictive approaches instead, for example, via conserved molecular markers, and in vitro and in silico approaches. Among them, adverse outcome pathways (AOPs) have been proposed to facilitate the prediction of molecular toxic effects at larger biological scales. Thus, more toxicological data are used to inform on ecotoxicological risks and vice versa. An AOP has been previously developed to predict reproductive toxicity of silver nanoparticles via oxidative stress on the nematode Caenorhabditis elegans (AOPwiki ID 207). Following this previous study, our present study aims to extend the biologically plausible taxonomic domain of applicability (tDOA) of AOP 207. Various types of data, including in vitro human cells, in vivo, and molecular to individual, from previous studies have been collected and structured into a cross‐species AOP network that can inform both human toxicology and ecotoxicology risk assessments. The first step was the collection and analysis of literature data to fit the AOP criteria and build a first AOP network. Then, key event relationships were assessed using a Bayesian network modeling approach, which gave more confidence in our overall AOP network. Finally, the biologically plausible tDOA was extended using in silico approaches (Genes‐to‐Pathways Species Conservation Analysis and Sequence Alignment to Predict Across Species Susceptibility), which led to the extrapolation of our AOP network across over 100 taxonomic groups. Our approach shows that various types of data can be integrated into an AOP framework, and thus facilitates access to knowledge and prediction of toxic mechanisms without the need for further animal testing. Environ Toxicol Chem 2024;00:1–14. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Refugees from diverse socio-cultural backgrounds and geopolitical locations face temporal challenges during their transition, yet more research needs to be conducted to understand their time conception in the host society. This study explores how North Korean refugees from remote rural areas in North Korea and China adjusted their time conception in a metropolitan city in South Korea. Data were collected through a pilot study (January-March 2017) and ethnographic fieldwork (February-July 2018), entailing semi-structured interviews, informal conversations, and field notes. Vygotsky’s psychological tool and Ricoeur’s interpretive approach were employed to solicit the mediation of time conception through organizational activities and narrative meanings. The analysis reveals themes that challenge refugees’ time conception reflecting North Korean values and daily activities—Kimilsungism, collectivism, and task-oriented attitude—and the changes in time conception on the sense of the self. Refugees’ learning in time conception is a holistic spiritual, social, and personal process. [ABSTRACT FROM AUTHOR]

Increasing concern over microplastics has recently brought increased attention to studies on microplastic toxicity. Here, we conduct a systematic review on toxicity of microplastics that focuses on identifying data gaps in the mechanisms of microplastic toxicity. We observe that microplastic toxicology research thus far has focused on ecotoxicity using apical endpoints and only a few studies deal with toxicity mechanisms. Based on this review, we propose putative Adverse Outcome Pathways (AOPs) applicable to microplastic management to understand microplastic toxicity. We matched toxicity mechanisms and apical endpoints to a key event (KE) and adverse outcome (AO) information from the AOP Wiki. Overall, our results suggest that the molecular initiating event (MIE) was reactive oxygen species (ROS) formation and the AO was increased mortality, decreased growth and feeding, and reproduction failure. However, there are a limited number of studies on toxicity mechanisms of microplastics and, therefore, evidence concerning the relationship between KEs is not sufficient. Clearly, more studies on toxicity mechanisms are required to fill these gaps in data. This study also suggests that the AOP framework is a suitable tool to integrate existing data from various literature sources and can identify data gaps in microplastic toxicity mechanisms. Image 1 • Microplastic toxicity mechanisms in terms of ecotoxicity and human health toxicity were reviewed. • Microplastic toxicology research has focused on ecotoxicity using apical endpoints. • Toxicity mechanisms matched with KE from the AOP Wiki and putative AOPs were proposed. • MIE is ROS formation and AOs are increasing mortality, reduction of growth, and reproduction failure. [ABSTRACT FROM AUTHOR]

Unusual cases of fatal lung injury, later determined to be a result of exposure to chemicals used as humidifier disinfectants, were reported among Korean children from 2006 to 2011. This resulted in considerable study of the pulmonary toxicity of humidifier disinfectant chemicals to establish the causal relationship between exposure and lung disease. However, the systemic toxicity of the former and health effects other than lung disease are not fully understood. Here, we investigated the effect of 5-chloro-2-methyl-4-isothiazoline-3-one and 2-methyl-4-isothiazolin-3-one (CMIT/MIT), among the humidifier disinfectants used in the accidents, on the development of metabolic toxicity in the model organism, Caenorhabditis elegans using an exposure scenario comparison. We screened the potential of CMIT/MIT to induce metabolic toxicity using C. elegans oga-1(ok1207) and ogt-1(ok1474) mutants. We also performed a pathway analysis based on C. elegans transcription factor RNAi library screening to identify the underlying toxicity mechanisms. Finally, to understand the critical window of exposure for metabolic toxicity, responses to exposure during different periods in the life cycles of the worms were compared. We determined that CMIT/MIT could induce metabolic toxicity through O-linked N -acetylglucosamine transferase and early life seems to be the critical window for exposure for metabolic toxicity for this substance. The O-linked N -acetylglucosamine transferase pathway is conserved from worms to humans; our results thus insinuate that early-life exposure to CMIT/MIT could cause metabolic health problems during adult life in humans. We therefore suggest that a systemic toxicity approach should be considered to comprehensively understand the adverse health effects of humidifier disinfectant misuse. • Metabolic toxicity of a biocide, CMIT/MIT, was investigated in C. elegans oga-1(ok1207) and ogt-1(ok1474) mutants. • CMIT/MIT causes metabolic toxicity via the O-linked N-acetylglucosamine transferase (OGT) pathway. • Oxidative stress, fatty acid metabolism and locomotive behavior were associated with CMIT/MIT-induced metabolic toxicity. • FOXO signaling pathway was involved in CMIT/MIT-induced metabolic toxicity. • Early life seems to be the critical window for exposure for metabolic toxicity of CMIT/MIT. [ABSTRACT FROM AUTHOR]

Copper‐tin (CuSn) nanomaterials have been receiving substantial attention due to their excellent thermal, electrical, and optical properties. However, how such properties are affected based on heat treatment temperature and chemical composition of copper and tin is still not very well understood. In this paper, CuSn nanofibers were fabricated by electrospinning a precursor solution of polyacrylonitrile, copper, and tin. Calcination temperatures were selected using thermogravimetric/differential thermal analysis (TG/DTA) and Fourier transform infrared (FT‐IR) results. Analytical techniques such as scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and ultraviolet photoelectron spectroscopy (UPS) were employed to investigate the physicochemical properties of the CuSn nanofibers. SEM images and EDS revealed the formation of pores on the nanofibers and high concentrations of tin were in the core, while copper was located on the surface. XRD results confirmed the monoclinic phase of Cu6Sn5 for the CuSn nanofibers because peaks for diffraction angles at 27.6°, 53.4°, and 60.0° were observed. XPS results showed that Cu―C and Sn―C bonds occur at binding energies around 932 and 484 eV, respectively. The work function of the CuSn NF heat treated at 150°C was calculated from the UPS spectra, and the value was 4.19 eV. [ABSTRACT FROM AUTHOR]

ATP-binding cassette (ABC) transporters constitute one of the largest gene families in all living organisms, most of which mediate transport across biological membranes by hydrolyzing ATP. However, detailed studies of ABC transporter genes in the important oil crop, soybean, are still lacking. In the present study, we carried out genome-wide identification and phylogenetic and transcriptional analyses of the ABC gene family in G. max. A total of 261 G. max ABC (GmABCs) genes were identified and unevenly localized onto 20 chromosomes. Referring to protein-domain orientation and phylogeny, the GmABC family could be classified into eight (ABCA-ABCG and ABCI) subfamilies and ABCG were the most abundantly present. Further, investigation of whole genome duplication (WGD) signifies the role of segmental duplication in the expansion of the ABC transporter gene family in soybean. The Ka/Ks ratio indicates that several duplicated genes are governed by intense purifying selection during evolution. In addition, in silico expression analysis based on RNA-sequence using publicly available database revealed that ABC transporters are differentially expressed in tissues and developmental stages and in dehydration. Overall, we provide an extensive overview of the GmABC transporter gene family and it promises the primary basis for the study in development and response to dehydration tolerance. [ABSTRACT FROM AUTHOR]

Abstract: We identified and characterized a partial cDNA of StAR-related lipid transfer domain containing protein gene from Chironomus riparius (CrSTART1) having homology with human MLN64 and Drosophila melanogaster START1 (DmSTART1) and evaluated the effects of cadmium chloride (Cd) and nonylphenol (NP) on its expression. Pfam analysis identified the presence of two StAR-related lipid transfer (START) domains in CrSTART1 having several conserved amino acid residues, characteristic of the MLN64 and DmSTART1. The mRNA expression of CrSTART1 was observed in all developmental stages. The modulation in the mRNA expression of CrSTART1 was investigated after exposure to different concentrations Cd (0, 2, 10, and 20mg/L) and NP (0, 10, 50, and 100μg/L) for different time intervals in fourth instar larvae of C. riparius. Significant downregulation of CrSTART1 mRNA was observed after exposure to 2, 10 and 20mg/L of Cd for 24, 48 and 72h. Significant upregulation of CrSTART1 was observed after exposure to 10 and 50μg/L of NP for 24, and 48h period. At 100μg/L of NP significant upregulation of CrSTART1 was observed after 12h and downregulated after 24, 48 and 72h. [Copyright &y& Elsevier]

Abstract: We characterized thioredoxin reductase 1 (TrxR1) from Chironomus riparius (CrTrxR1) and studied its expression under oxidative stress. The full-length cDNA is 1820bp long and contains an open reading frame (ORF) of 1488bp. The deduced CrTrxR1 protein has 495 amino acids and a calculated molecular mass of 54.41kDa and an isoelectric point of 6.15. There was a 71bp 5’ and a 261bp 3'' untranslated region with a polyadenylation signal site (AATAAA). Homologous alignments showed the presence of conserved catalytic domain Cys–Val–Asn–Val–Gly–Cys (CVNVGC), the C-terminal amino acids ‘CCS’ and conserved amino acids required in catalysis. The expression of CrTrxR1 is measured using quantitative real-time PCR after exposure to 50 and 100mg/L of paraquat (PQ) and 2, 10 and 20mg/L of cadmium chloride (Cd). CrTrxR1 mRNA was upregulated after PQ exposure at all conditions tested. The highest level of CrTrxR1 expression was observed after exposure to 10mg/L of Cd for 24h followed by 20mg/L for 48h. Significant downregulation of CrTrxR1 was observed after exposure to 10 and 20mg/L of Cd for 72h. This study shows that the CrTrxR1 could be potentially used as a biomarker of oxidative stress inducing environmental contaminants. [Copyright &y& Elsevier]

Abstract: Chironomus riparius, a non-biting midge (Chironomidae, Diptera), is extensively used as a model organism in aquatic ecotoxicological studies, although little is known about its genome sequences. Ecdysteroids are steroid hormones that play an important role in development, growth, moulting of larva, and reproduction in Chironomus spp. The effect of ecdysteroids is mediated by their binding to the ecdysteroid receptor (EcR). To study the effect of environmental stressors, nonylphenol and silver nanoparticles (AgNPs), on the modulation of EcR mRNA, in this study, full length cDNA of C. riparius ecdysone receptor (CrEcR) was identified from the Expressed Sequence Tags (ESTs) database and expression of the corresponding mRNA was analyzed following exposure to nonylphenol and AgNPs. The CrEcR cDNA was 2548 base pairs (bp) in length, with a 5′ untranslated region (UTR) of 242bp and a 3′ UTR of 684bp. The open reading frame contains 1617 nucleotides, encoding 539 amino acids with a predicted molecular weight of 61kDa and pI of 5.89, and revealed the presence of several domains associated with DNA binding, dimerization, ligand binding and transcriptional activation characteristic of steroid receptor family members. It was found that the expression level of CrEcR was significantly up-regulated on exposure to nonylphenol and significant up or down regulation was observed on exposure to AgNPs. These finding shows that nonylphenol as well as AgNPs could modulate the ecdysone nuclear receptor and may have significant implications in different developmental stages in C. riparius. [Copyright &y& Elsevier]

Abstract: In this study, the effect of organophosphorous (OP) pesticide, fenitrothion (FT), on the non-target organism was investigated using the soil nematode, Caenorhabditis elegans. Toxicity was investigated on multiple biological levels, from organism to molecular levels, such as, immoblity, growth, fertility, development, acetyl cholinesterase (AChE) activity and stress-response gene expressions. FT may provoke serious consequences on the C. elegans population, as it induced significant developmental disturbance. As expected, FT exposure inhibits AChE activity of C. elegans. The increased expression of the cytochrome p450 family protein 35A2 (cyp35a2) gene was also observed in FT exposed worms. To experimentally demonstrate the relationships between organism-level effects and the cyp35a2 gene expression in FT-exposed C. elegans, the integration of the gene expression with biochemical-, and organism level endpoints were attempted using a C. elegans cyp35a2 RNA interference (RNAi) and cyp35a2 mutant (gk317). The 24h-EC50s of C. elegans on FT exposure were in the order of cyp35a2 RNAi in cyp35a2 mutant (gk317)> cyp35a2 mutant (gk317)> cyp35a2 RNAi in wildtype (N2)> wildtype (N2). The higher EC50 values of cyp35a2 RNAi and cyp35a2 mutant (gk317) compared to that of wildtype C. elegans strongly supported that cyp35a2 gene plays an important role in the toxicity of FT towards C. elegans. The experiments with cyp35a2 RNAi also indicated that the development disturbance and decreased AChE activity, which were observed in FT exposed wildtype C. elegans were significantly rescued in the cyp35a2 RNAi C. elegans. Overall results suggest that the cyp35a2 may be an important gene for exerting FT toxicity in C. elegans. [Copyright &y& Elsevier]

Abstract: A full-length ribosomal protein L15 cDNA from Chironomus riparius (CrRPL15) was identified from the Expressed Sequence Tag (EST) database developed vt 454 pyrosequencing, and expression of the corresponding mRNA was analyzed during different developmental stages and following exposure to Cadmium chloride (Cd) and Silver nanoparticles (AgNPs). The CrRPL15 cDNA contains an open reading frame (ORF) of 615 base pairs (bp) encoding a putative protein of 204 amino acids, with a high level of sequence similarity to RPL15 proteins from other species. The consensus sequence, GXXXXGKS, which is present in other RPL15 proteins, was also present in the putative CrRPL15 protein. The CrRPL15 transcript was present at all life stages, but was most abundant in the eggs. Expression of the CrRPL15 gene was significantly down-regulated in response to exposure to both Cd and AgNPs. In contrast, expression of the heat shock protein 70 (HSP70) gene, a general stress indicator, was significantly up-regulated. [Copyright &y& Elsevier]

Abstract: Calcium plays a critical role in a variety of cellular processes in cells. However, relatively little is known about the biological effects of Ca2+ signaling on morphogenesis and pathogenesis in the rice blast fungus Magnaporthe oryzae compared to other signaling pathways. We have previously demonstrated that MoPLC1-mediated calcium regulation is important for infection-related development and pathogenicity in M. oryzae. In the present study, four genes encoding phospholipase C (PLC) isozymes (MoPLC2 to MoPLC5), which differ from MoPLC1 in their domain organization, were additionally identified. The C2 domain involved in Ca2+-dependent membrane binding is found only in MoPLC2 and MoPLC3. Detailed functional analysis using deletion mutants for MoPLC2 and MoPLC3 indicated that MoPLC2 and MoPLC3 play essential roles in development. The two deletion mutants for MoPLC2 and MoPLC3 showed reduced conidiation and a defect in appressorium-mediated penetration. Reintroduction of the genes restored defects of ΔMoplc2 and ΔMoplc3. Notably, ΔMoplc2 and ΔMoplc3 mutants developed multiple appressoria on separate germ tubes of a conidium, indicating that MoPLC2- and MoPLC3-regulated signaling suppresses a feedback loop of a pathway for appressorial development. The similarity in phenotypic defects between the two mutants indicates that both MoPLC2 and MoPLC3 are important for regulation of appropriate levels of signaling molecules in a similar manner. Comparative analysis indicated that the two MoPLCs-mediated signaling pathways have interrelated, but distinct, roles in the development of M. oryzae. [Copyright &y& Elsevier]

Abstract: In this study, we report the identification and characterization of 13 cytosolic GST genes in Chironomus riparius from Expressed Sequence Tags (ESTs) database generated using pyrosequencing. Comparative and phylogenetic analyses were undertaken with Drosophila melanogaster and Anopheles gambiae GSTs and 3 Delta, 4 Sigma, 1 each in Omega, Epsilon, Theta, Zeta and 2 unclassified classes of GSTs were identified and characterized. The relative mRNA expression levels of all of the C. riparius GSTs (CrGSTs) genes under different developmental stages were varied with low expression in the larval stage. The antioxidant role of CrGSTs was studied by exposing fourth instar larvae to a known oxidative stress inducer Paraquat and the relative mRNA expression to different concentrations of cadmium (Cd) and silver nanoparticles (AgNPs) for various time intervals were also studied. All the CrGSTs showed up- or down regulation to varying levels based upon the concentration, and duration of exposure. The highest mRNA expression was noticed in Delta3, Sigma4 and Epsilon1 GST class in all treatments. These results show the role of CrGST genes in defense against oxidative stress and its potential as a biomarker to Cd and AgNPs exposure. [Copyright &y& Elsevier]

An essay is presented which discusses South Korean distribution of Chinese films. Restrictions on the distribution of Chinese-language films, South Korean cultural policies, and the popularity of martial arts films produced in Hong Kong, China are examined. Rivalry between the Japanese, South Korean, and Chinese film industries is also explored.

Abstract: In this study, the potentially harmful effect of the exposure to fumed and porous silicon dioxide (silica) nanoparticles was investigated using human bronchial epithelial cell, Beas-2B, with a focus on the involvement of oxidative stress as the toxic mechanism. Silica nanoparticles-induced oxidative stress was assessed by examining the formation of reactive oxygen species (ROS) and induction of antioxidant enzymes, such as superoxide dismutase (SOD) and heme oxygenase-1 (HO-1). Subsequently, to understand the mechanism of nanoparticles-induced oxidative stress, the involvement of oxidative stress-responding transcription factors, such as, nuclear factor-kappaB (NF-κB) and nuclear factor-E2-related factor-2 (Nrf-2), as well as the mitogen-activated protein (MAP) kinase signal transduction pathway were investigated. From the overall results, silica nanoparticles exerted toxicity via oxidative stress, which lead to the induction of HO-1 via the Nrf-2–ERK MAP kinase signaling pathway; cells exposed to porous silica nanoparticles showed a more sensitive response than those exposed to fumed silica. Nevertheless, the parameters tested were rather limited in terms of gaining a full understanding of the oxidative stress and cellular response due to exposure to silica nanoparticles. Further studies on the mechanism by which silica nanoparticles induce the Nrf-2–ERK MAP kinase pathway, to more clearly elucidate the silica-induced oxidative stress, as well as on the relationship between the physico-chemical properties of nanoparticles and their cytotoxicity are warranted to gain an understanding of the phenomenon of different sensitivities between porous and fumed silica. [Copyright &y& Elsevier]

Abstract: Octachlorostyrene (OCS) is a ubiquitously distributed compound, of which, ecotoxicological property is little known. To investigate the ecotoxicity of OCS, short- and long-term experiments were conducted under controlled laboratory conditions, using the aquatic midge, Chironomus tentans, as a biological model system. Ecophysiological responses using organism/population level endpoints, such as growth, reproduction and development, were investigated. Moreover, oxidative stress-related parameters and the expression of heat shock protein and hemoglobin gene were also investigated as potential biomarkers for OCS exposure. Significant disturbance in male/female adult ratio and on oviposition by chronic exposure to OCS suggests that this compound may have serious consequences on Chironomus population by affecting reproduction. To elucidate the mechanism of these speculated phenomena, direct experimental demonstrations on the relationships between observed ecotoxicological response and upstream-induced molecular/biochemical events may be needed. [Copyright &y& Elsevier]

Abstract: To understand the molecular mechanism of previously observed cerium oxide (CeO2) nanoparticles-induced oxidative stress, an in vitro toxicity assay was conducted using human bronchial epithelial cell, Beas-2B, focusing on the involvement of the oxidative stress responding signal transduction pathway and transcription factors in the toxicity of CeO2 nanoparticles. Extracellular signal-regulating kinase (ERK), p38 and c-Jun N-terminal kinase (JNK) signaling pathways, along with nuclear factor-kappaB (NF-κB) and nuclear factor-E2-related factor-2 (Nrf-2), were investigated as the upstream events of oxidative stress from exposure to CeO2 nanoparticles. The overall results suggest that CeO2 nanoparticles may exert their toxicity through oxidative stress, as they cause significant increases in the cellular reactive oxygen species (ROS) concentrations, subsequently leading to the strong induction of heme oxygenase-1 (HO-1) via the p38-Nrf-2 signaling pathway. Further studies on the mechanism by which CeO2 nanoparticles induce the p38-Nrf-2 signaling pathway are warranted for a better understanding of the CeO2 nanoparticles-induced oxidative stress; studies with other signaling pathways, with concentration–response and time course experiments would also be justified. [Copyright &y& Elsevier]

Abstract: Ca2+-dependent signaling plays important roles in cellular development and metabolism in fungi. Pharmacological and molecular evidence clearly indicates that Ca2+-dependent signaling is required for infection-related development and pathogenicity in the rice blast fungus Magnaporthe oryzae. However, little information is available on downstream regulators in the Ca2+-dependent signaling pathway. To understand the role of a calcineurin-dependent transcription factor in the rice blast fungus, an ortholog of Saccharomyces cerevisiae CRZ1 in M. oryzae, MoCRZ1, was identified and functionally characterized. The Δmocrz1 mutant exhibited impaired growth in the presence of Ca2+ ions or cell wall perturbing agents. The Δmocrz1 mutant also showed reduced conidiation and reduced pathogenicity, which is mainly due to a defect in host penetration. MoCRZ1 fused to EGFP was trans-localized into the nucleus in a Ca2+/calcineurin-dependent manner. The MoCRZ1 gene is also required for the calcineurin-dependent transcriptional induction of FKS1, a gene encoding a β-1,3 glucan synthase, CHS2 and CHS4, genes encoding two chitin synthases, and PMC and PMR gene families encoding P-type ATPases in response to Ca2+. These results suggest that MoCRZ1 is a downstream regulator in Ca2+-dependent signaling for pathogenicity in M. oryzae, and its biochemical mechanisms are well conserved among fungal species. [Copyright &y& Elsevier]

Abstract: The effects of environmental contaminants (i.e., nonylphenol, bisphenol A diglycidyl ether, benzo[a]pyrene, chlorpyriphos, paraquat dichloride, and lead nitrate) on Chironomus hemoglobin were investigated in the 4th instar larvae of Chironomus riparius (Diptera: Chironomidae), with respect to the total hemoglobin contents, individual globin gene expression, individual globin protein expression and hemoglobin oxidation. In our studies, 7 and 6 globin isoforms were preliminarily characterized by molecular weight and isoelectric point, respectively, in the 4th instar larvae of C. riparius. Most chemicals were unable to modify the total hemoglobin contents, however, the expression patterns of the globin transcript and proteins suggest that C. riparius globin exists in both inducible and consecutively expressed forms, with multiplicity that may allow this animal to better adapt toward stressful environmental conditions, including pollution stress. The oxyhemoglobin was observed to be downregulated in C. riparius on exposure to bisphenol A and chlorpyriphos, probably reflecting its increased autoxidation to methemoglobin. The overall results would suggest that globin can be a target molecule of environmental contaminants, and of the tested parameters, the alteration of individual globin levels (i.e., mRNA or protein levels) may have potential for the development of a biomarker for ecotoxicity monitoring. [Copyright &y& Elsevier]

Abstract: In this study, a preliminary characterization of the multiplicity of Chironomus hemoglobin (Hb) was conducted on the larvae of Chironomus tentans Mg. (Diptera: Chironomidae) by the molecular mass and isoelectric point. In order to identify Chironomus Hb as potential biomarker of environmental contamination, alteration of individual Hb by exposure to environmental chemicals, namely, nonylphenol, benzo[a]pyrene, chloropyriphos and cadmium chloride, were evaluated. To validate the ecotoxicological relevance of Chironomus Hb as a potential biomarker, ecotoxicity test using growth rate as toxic endpoint was also conducted. This study revealed a striking heterogeneity in C. tentans Hb; 10 Hb isoforms were observed in the larvae of 4th instar C. tentans by their molecular mass and by their isoelectric point. Chemical-induced alteration of individual Hb expression suggests that C. tentans Hb can be a target molecule for chemical exposure. Overall results suggest that the expression pattern of Hb proteins may potentially contribute to the development of a biomarker for ecotoxicity monitoring in C. tentans. [Copyright &y& Elsevier]

Abstract: Cerium oxide nanoparticles of different sizes (15, 25, 30, 45nm) were prepared by the supercritical synthesis method, and cytotoxicity was evaluated using cultured human lung epithelial cells (BEAS-2B). Exposure of the cultured cells to nanoparticles (5, 10, 20, 40μg/ml) led to cell death, ROS increase, GSH decrease, and the inductions of oxidative stress-related genes such as heme oxygenase-1, catalase, glutathione S-transferase, and thioredoxin reductase. The increased ROS by cerium oxide nanoparticles triggered the activation of cytosolic caspase-3 and chromatin condensation, which means that cerium oxide nanoparticles exert cytotoxicity by an apoptotic process. Uptake of the nanoparticles to the cultured cells was also tested. It was observed that cerium oxide nanoparticles penetrated into the cytoplasm and located in the peri-region of the nucleus as aggregated particles, which may induce the direct interaction between nanoparticles and cellular molecules to cause adverse cellular responses. [Copyright &y& Elsevier]

Abstract: For the screening of the risk from environmental contamination, the cytotoxic/genotoxic effects of various model pollutants were determined using an in vivo system comprised of human HeLa cells; the ecotoxicity was also determined using the acute and genotoxicity tests on two aquatic sentinel species widely used in biomonitoring, namely, freshwater crustacean, Daphnia magna and larva of aquatic midge, Chironomus tentans. Nonylphenol (NP), bisphenol A (BPA), bis(2-ethylhexyl) phthalate (DEPH) and paraquat dichloride (PQ) were used as the model pollutants. The results showed that exposure of HeLa cells to NP, BPA and DEHP was sufficient for the expression of noticeable genotoxic and cytotoxic effects. Ecotoxicity results showed that, as expected, D. magna was more sensitive than C. tentans to chemical exposure. BPA may exert a genotoxic effect on D. magna and C. tentans, given that DNA strand breaks increased in both species exposed to this compound, whereas NP-induced DNA damage occurred only in C. tentans. In vivo genotoxic data obtained in aquatic sentinel species could provide valuable information for freshwater quality monitoring. From the results of the present study, the use of cytotoxic, genotoxic and ecotoxic tests using human cell system, as well as, biomonitoring species, seems to be relevant for preliminary evaluation of the human health and ecological effects of pollutants and thus, a promising screening tool for environmental monitoring and risk assessment. [Copyright &y& Elsevier]

This article focuses on point of view (POV) shots in films. Recent literature in the philosophy of film not only attempts to explain the cognitive processes involved in engaging with fiction film, but also addresses the textual cues that contribute to evoking an emotional response from the viewer. Murray Smith focuses on POV shots as one of the important features that encourage the viewer to imagine the character's experience from the inside. The article focuses on Smith's claim that POV shots tend to activate central imagining.

Cognitive theories of emotions have provided us with explanations of how we emotionally engage with fiction, when we are aware that what is depicted is fictional. However, these theories left an important question unanswered: namely, what kinds of emotional responses to fiction are warranted responses. The main focus of this paper is how our emotional responses to fiction can be aesthetically warranted—that is, how emotions directed to fiction can be warranted given the fact that its object is an artwork. I consider three possible explanations of this phenomenon: the real-life principle, a correspondence model, and a functional model. I argue that the real-life principle and the correspondence model fall short of explaining how our emotional responses to film are aesthetically warranted, and instead I argue that a functional model provides such an explanation. In this paper, I will primarily focus on fiction films, although I will address novels and other art forms where necessary. [ABSTRACT FROM AUTHOR]

Criticizes the cognitive theory of fiction-directed emotion and proposes a noncognitivist approach toward fiction-directed emotion. Shortcomings of the cognitive approach; Impact of formal properties in evoking emotions; Likely mechanisms that direct emotional responses.

In this study, an attempt was made to develop a method to estimate oxidative damage of individual genes for assessing chemopreventive potential of dietary or medicinal plants. Oxidative damage was investigated on the two genes in gastric mucosal tissue infected with Helicobacter pylori, which were genes of glyceraldehydes-3-phosphate dehydrogenase (GAPDH), a house-keeping gene, and gene of insulin-like growth factor II receptor (IGFIIR), a gene known to be mutated frequently in gastric carcinoma. The oxidative damage in genomic DNA in the above tissue was confirmed by immunohistochemical study using monoclonal antibody to 8-hydroxyguanine (oh8G), which showed much higher degree of staining in their nuclei. Using the method we developed, it was demonstrated that the number of oh8G (indicated by 8-hydroxyguanine glycosylase (OGG1) sensitive sites) in GAPDH was almost not changed in H. pylori-infected tissue but in IGFIIR, it increased significantly. These results indicate that this method is valid for the estimate of oxidative damage of individual genes and also showed that the susceptibility of genomic DNA to attack of reactive oxygen species is not homogeneous but different depending upon the region of DNA. We expect to use this method in studies of carcinogenic mechanism and chemoprevention since it can provide more specific information pertaining to individual genes we are interested in. [Copyright &y& Elsevier]

Polystyrene (PS) nanoplastic exposure has been shown to affect the viability of neuronal cells isolated from mouse embryonic brains. However, the viability of mouse embryonic fibroblasts (MEFs) was not affected although PS nanoplastics accumulated in the cytoplasm. It is currently unknown whether MEFs do not respond to PS nanoplastics or their cellular functions are altered without compromising viability. Here, we found that PS nanoplastics entered the cells via endocytosis and were then released into the cytoplasm, probably by endosomal escape, or otherwise remained in the endosome. Oxidative and inflammatory stress caused by intracellular PS nanoplastics induced the antioxidant response pathway and activated the autophagic pathway. However, colocalization of the autophagic marker LC3B and PS nanoplastics suggested that PS nanoplastics in the cytoplasm might interfere with normal autophagic function. Furthermore, autophagic flux could be impaired, probably due to accumulation of PS nanoplastic-containing lysosomes or autolysosomes. Intriguingly, the level of accumulated PS nanoplastics decreased during prolonged culture when MEFs were no longer exposed to PS nanoplastics. These results indicate that accumulated PS nanoplastics are removed or exported out of the cells. Therefore, PS nanoplastics in the cytoplasm affect cellular functions, but it is temporal and MEFs can overcome the stress caused by PS nanoplastic exposure. [ABSTRACT FROM AUTHOR]

• 50 plastic additives are screened using ToxCast to identify MP toxicity mechanisms. • Deep learning models were developed to predict missing data. • Assays that could reflect animal toxicity were found through correlation analysis. • Neurotoxicity, inflammation, lipid metabolism, and cancer are potential mechanisms. • Potential Adverse Outcome Pathways relevant to MP were proposed. Various additives are used in plastic products to improve the properties and the durability of the plastics. Their possible elution from the plastics when plastics are fragmented into micro- and nano-size in the environment is suspected to one of the major contributors to environmental and human toxicity of microplastics. In this context, to better understand the hazardous effect of microplastics, the toxicity of chemical additives was investigated. Fifty most common chemicals presented in plastics were selected as target additives. Their toxicity was systematically identified using apical and molecular toxicity databases, such as ChemIDplus and ToxCast™. Among the vast ToxCast assays, those having intended gene targets were selected for identification of the mechanism of toxicity of plastic additives. Deep learning artificial neural network models were further developed based on the ToxCast assays for the chemicals not tested in the ToxCast program. Using both the ToxCast database and deep learning models, active chemicals on each ToxCast assays were identified. Through correlation analysis between molecular targets from ToxCast and mammalian toxicity results from ChemIDplus, we identified the fifteen most relevant mechanisms of toxicity for the understanding mechanism of toxicity of plastic additives. They are neurotoxicity, inflammation, lipid metabolism, and cancer pathways. Based on these, along with, previously conducted systemic review on the mechanism of toxicity of microplastics, here we have proposed potential adverse outcome pathways (AOPs) relevant to microplastics pollution. This study also suggests in vivo and in vitro toxicity database and deep learning model combined approach is appropriate to provide insight into the toxicity mechanism of the broad range of environmental chemicals, such as plastic additives. [ABSTRACT FROM AUTHOR]

As three academic researchers resisting the existing recognition order through generative, non-instrumentalizing relationships, we represent a substantive move away from the prevailing developmental model of doctoral student preparation. We highlight the struggle against misrecognition in the academy. Drawing on duoethnographic methods, we explore the nature of doctoral study and effective approaches to mentoring doctoral students as future researchers and university faculty. We contribute to the literature on mentoring non-traditional adult learners in higher education by defining organic mentoring as non-instrumental, relational, and collaborative. Additionally, we extend the use of duoethnography to trioethnography by involving three researchers in dialogic storytelling to illuminate overlapping experiences from different angles. Lastly, we further develop the use of Axel Honneth's recognition theory by linking it to adult mentoring in doctoral study. [ABSTRACT FROM AUTHOR]

Silica nanoparticles (SiNPs) are one of the popular nanomaterials used in industrial manufacturing, synthesis, engineering, and medicine. Recently, mechanisms underlying toxicity of silica nanoparticles have been reported; however, their uptake mechanisms have still not fully understood. In this study, toxicity of SiNPs was investigated in the nematode Caenohabditis elegans by using microarray and pathway analysis focusing the uptake mechanisms and their impact on toxicity. Physicochemical characterization of SiNPs was performed using dynamic light scattering (DLS) and zeta potential. No mortality was observed after 24 h exposure to SiNPs. However, reproductive ability was significantly reduced at the same concentrations. To ascertain a global mechanism of toxicity, microarray was conducted on C. elegans exposed to 10 mg/L SiNPs (20% reduction in reproductive ability). Microarray results indicated that genes involved in reproduction, such as msp (Major Sperm Protein) genes, were significantly downregulated in C. elegans exposed to SiNPs. Pathway analyses on differentially expressed genes (DEGs) revealed that endocytic pathway as a major pathway involved in the uptake of SiNPs. Involvement of endocytic pathway in the uptake of SiNPs was assessed using specific inhibitors (methyl-β-cyclodextrin, chlorpromazine, and LY294002 for caveolin-, clathrin-, and pinocytosis-mediated endocytosis, respectively). The inhibitor assay indicated that an internalization process facilitated by clathrin-mediated endocytosis is involved in the uptake of SiNPs. Functional analysis using endocytosis defective mutants, (i,e. cav-1, cup-2, and chc-1) confirmed the role of endocytosis on the reproductive toxicity of SiNPs. Overall results suggest that clathrin-mediated endocytosis pathway is a potential mechanism of uptake of SiNPs in C. elegans that in turn, affects general toxic outcome, such as, decrease in reproductive ability. • Reproductive ability was significantly reduced by SiNPs exposure. • The microarray profiling showed the uptake mechanism and reductive of fertility. • The clathrin-mediated endocytosis pathway is involved in internalization of SiNPs. [ABSTRACT FROM AUTHOR]

Ecotoxicity tests conducted under well-controlled lab conditions often do not reflect the real environmental conditions. To this end, we designed an ecotoxicity test using an aquatic midge, Chironomus riparius , raised in metal-contaminated field sediments (MCFS), which reflect the real environmental conditions, for five consecutive generations (F0–F4) followed by a toxic response to arsenic exposure (as a second challenge). The toxic responses (i.e. DNA damage, DNA methylation, stress response gene expression, and mortality) were compared to those organisms reared in lab sediments (LS). Under the MCFS condition, increased adult emergence was observed for the second and third generations (F1 and F2), while a decreased tendency was evident thereafter (F3 and F4) compared to that of F0. When comparing C. riparius raised in MCFS or LS exposed to arsenic, increased sensitivity (declined survival) was observed in the larvae from F2. However, that tendency was not present in F4 of the MCFS midges, indicating a possible physiological adaptation. Increased DNA damage was observed in the MCFS-exposed organisms (F0, F2, and F4) compared to the those exposed to LS, particularly at F0. Arsenic exposure induced hypermethylation at F0 and, in contrast, hypomethylation at the later generations (F2, F4) in the MCFS-exposed organisms. Global DNA methylation results were supported by the expression of genes involved in enzymatic methylation. Moreover, alterations in oxidative stress related to gene expression showed that significant oxidative stress and perturbation of glutathione reserves occurred under the MCFS and the subsequent arsenic exposure conditions. Overall, our results suggest that multigenerational rearing under MCFS conditions resulted in physiological adaptation of C. riparius to metal exposure, specifically at later generations, which in turn modulated its response to arsenic stress through possible genetic and epigenetic mechanisms. Unlabelled Image • Multigenerational exposure in MCFS showed physiological adaptation. • Higher sensitivity in early generations -development, DNA damage, oxidative stress • Increased tolerance in later generations to second challenge (arsenic exposure) • Alteration of global DNA methylation & its related genes (DNMTs) • Possible role of epigenetic in sensitivity to physiological adaption [ABSTRACT FROM AUTHOR]

Recent studies have highlighted the potential of the ToxCast™ database for mechanism-based prioritization of chemicals. To explore the applicability of ToxCast data in the context of regulatory inventory chemicals, we screened 510 priority existing chemicals (PECs) regulated under the Act on the Registration and Evaluation, etc. of Chemical Substances (K-REACH) using ToxCast bioassays. In our analysis, a hit-call data matrix containing 298984 chemical-gene interactions was computed for 949 bioassays with the intended target genes, which enabled the identification of the putative toxicity mechanisms. Based on the reactivity to the chemicals, we analyzed 412 bioassays whose intended target gene families were cytochrome P450, oxidoreductase, transporter, nuclear receptor, steroid hormone, and DNA-binding. We also identified 141 chemicals based on their reactivity in the bioassays. These chemicals are mainly in consumer products including colorants, preservatives, air fresheners, and detergents. Our analysis revealed that in vitro bioactivities were involved in the relevant mechanisms inducing in vivo toxicity; however, this was not sufficient to predict more hazardous chemicals. Overall, the current results point to a potential and limitation in using ToxCast data for chemical prioritization in regulatory context in the absence of suitable in vivo data. • A mechanism-based prioritization approach for identifying potential toxicants was proposed. • Significant ToxCast bioassays and priority existing chemicals were prioritized based the reactiveness. • Genes targeted by selected in vitro bioassays were involved in relevant mechanism inducing apical in vivo toxicity. • A potential and limitation of the application of ToxCast data to regulatory inventory chemicals were presented. [ABSTRACT FROM AUTHOR]

Discusses the article `Visible Traces: Documentary and the Contents of Photographs,' by Gregory Currie. How Currie defined documentary; Arguments on the scope of Currie's definition; Major claim of Currie on documentaries.

The copper (Cu) biotic ligand model (BLM) has been used for ecological risk assessment by taking into account the bioavailability of Cu in freshwater. The Cu BLM requires data for many water chemistry variables, such as pH, major cations, and dissolved organic carbon, which can be difficult to obtain from water quality monitoring programs. To develop an optimized predicted no‐effect concentration (PNEC) estimation model based on an available monitoring dataset, we proposed an initial model that considers all BLM variables, a second model that requires variables excluding alkalinity, and a third model using electrical conductivity as a surrogate for the major cations and alkalinity. Furthermore, deep neural network (DNN) models have been used to predict the nonlinear relationships between the PNEC (outcome variable) and the required input variables (explanatory variables). The predictive capacity of DNN models was compared with the results of other existing PNEC estimation tools using a look‐up table and multiple linear and multivariate polynomial regression methods. Three DNN models, using different input variables, provided better predictions of the Cu PNECs compared with the existing tools for the following four test datasets: Korean, United States, Swedish, and Belgian freshwaters. Consequently, it is expected that Cu BLM–based risk assessment can be applied to various monitoring datasets, and that the most applicable model among the three different types of DNN models could be selected according to data availability for a given monitoring database. Environ Toxicol Chem 2023;42:2271–2283. © 2023 SETAC [ABSTRACT FROM AUTHOR]

Nanoplastics (NPs) are potentially toxic and pose a health risk as they can induce an inflammatory response and oxidative stress at cellular and organismal levels. Humans can be exposed to NPs through various routes, including ingestion, inhalation, and skin contact. Notably, uptake into the body via inhalation could result in brain accumulation, which may occur directly across the blood-brain barrier or via other routes. NPs that accumulate in the brain may be endocytosed into neurons, inducing neurotoxicity. Recently, we demonstrated that exposure to polystyrene (PS)-NPs reduces the viability of neurons. We have also reported that inhibiting the retrograde transport of PS-NPs by histone deacetylase 6 (HDAC6) prevents their intracellular accumulation and promotes their export in mouse embryonic fibroblasts. However, whether HDAC6 inhibition can improve neuronal viability by increasing exocytosis of PS-NPs from neurons remains unknown. In this study, mice were intranasally administered fluorescent PS-NPs (PS-YG), which accumulated in the brain and showed potential neurotoxic effects. In cultured neurons, the HDAC6 inhibitor ACY-1215 reduced the fluorescence signal detected from PS-YG, suggesting that the removal of PS-YG from neurons was promoted. Therefore, these results suggest that blocking the retrograde transport of PS-NPs using an HDAC6 inhibitor can alleviate the neurotoxic effects of PS-NPs that enter the brain. • Intranasal administration of PS-NPs causes their accumulation in the mouse brain. • PS-NP accumulation in the mouse brain induces acute neurotoxic effects. • HDAC6 inhibition results in the rapid export of PS-NPs from neurons by exocytosis. • The rapid export of PS-NPs from neurons alleviates neurotoxic effects of PS-NPs. • The rapid export of PS-NPs from neurons reduces oxidative stress induced by PS-NPs. [ABSTRACT FROM AUTHOR]

Universal Design for Learning (UDL) is a framework for the teaching–learning transaction that conceptualizes knowledge through learner-centered foci emphasizing accessibility, collaboration, and community. Given the importance of access to achieving social justice, UDL is a promising approach to meeting all learners’ needs more effectively. In this article, the history and philosophy of UDL are discussed and elaborated, followed by an explanation of how the principles of UDL were used to improve an existing online course offering for adult learners. [ABSTRACT FROM AUTHOR]

An adverse outcome pathway (AOP) framework can facilitate the use of alternative assays in chemical regulations by providing scientific evidence. Previously, an AOP, peroxisome proliferative-activating receptor gamma (PPARγ) antagonism that leads to pulmonary fibrosis, was developed. Based on a literature search, PPARγ inactivation has been proposed as a molecular initiating event (MIE). In addition, a list of candidate chemicals that could be used in the experimental validation was proposed using toxicity database and deep learning models. In this study, the screening of environmental chemicals for MIE was conducted using in silico and in vitro tests to maximize the applicability of this AOP for screening inhalation toxicants. Initially, potential inhalation exposure chemicals that are active in three or more key events were selected, and in silico molecular docking was performed. Among the chemicals with low binding energy to PPARγ, nine chemicals were selected for validation of the AOP using in vitro PPARγ activity assay. As a result, rotenone, triorthocresyl phosphate, and castor oil were proposed as PPARγ antagonists and stressor chemicals of the AOP. Overall, the proposed tiered approach of the database- in silico - in vitro can help identify the regulatory applicability and assist in the development and experimental validation of AOP. [Display omitted] • A tiered approach for identify potential stressors of AOP was proposed. • Potential inhalation exposure and hazardous chemicals were collected from database. • In silico molecular docking identifies chemicals with low binding energy to PPARγ. • 3 chemicals were proposed as PPARγ antagonists by using in vitro PPARγ activity assay. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) are strong oxidants, and have attracted considerable attention in both biological and environmental fields. Although various methods for ROS detection, including optical and electrochemical techniques, have been developed, they still face challenging issues in terms of poor sensitivity, reproducibility, stability, and in vivo applicability. Here, we present a sensitive and selective optical sensor for ROS detection, based on single plasmonic nanoprobes and redox-active cytochrome c (Cyt c )-mediated plasmon resonance energy transfer. By measuring the spectral changes of plasmonic nanoprobes, derived from the unique molecular absorption of Cyt c in accordance with the redox state, calibration curves for H 2 O 2 , a representative ROS, in various media were obtained over a wide concentration range from 100 mM to 1 nM. Limit of detection and limit of quantification in accordance with the used medium were determined from 8.3 to 12.8 nM and from 27.6 to 42.7 nM, respectively. Selectivity coefficients for major interfering solutes were much lower than 0.1 indicating a good selectivity for ROS. From the dynamic spectral changes, we sensitively monitored ROS generated in Caenorhabditis elegans ( C. elegans ) exposed to graphene oxide. Based on the calibration curves, we also determined ROS levels in various aquatic environments, such as river streams and a small pond, as a way of environmental monitoring. We believe that our approach could provide an avenue for achieving dynamic and sensitive monitoring of ROS in toxicological, biological, and environmental fields in the future. [ABSTRACT FROM AUTHOR]

Biotic ligand models (BLMs) and the sensitivities of indigenous species are used to assess the environmental risk considering the bioavailability of metals, such as nickel. However, the BLM‐based acute–to–chronic ratio (ACR) is required if the predicted no‐effect concentration (PNEC) cannot be derived from the chronic species sensitivity distribution (SSD). The applicability of the ACR approach for estimating BLM‐based PNEC for nickel from acute toxicity data was evaluated in the present study. The BLM‐based acute SSD for nickel was built using the sensitivities of 21 indigenous species and different taxon‐specific BLMs for each taxonomic group. To predict the acute sensitivity of invertebrates, the chronic crustacean nickel BLM with pH effect term, which can account for nickel toxicity at high pH levels, was used. This was used instead of the existing acute BLM for crustacean, which has too narrow a pH range to cover the pH dependency of toxicity. The final BLM‐based ACR of nickel, determined within a factor of 1.53 from the species‐specific acute and chronic sensitivities of the six species, was more reliable than the typical ACR estimated within a factor of 1.84. A linear relationship (r2 = 0.95) was observed between the PNECs using BLM‐based ACR and the PNECs derived from the BLM‐based chronic SSD of the European Union Risk Assessment Reports. In conclusion, the BLM‐based PNEC for nickel could be derived using the ACR approach, unlike when copper BLM was applied. The BLM‐based ACR for nickel is the first result calculated by directly comparing acute and chronic species sensitivities, and will contribute to the application of BLM‐based risk assessment in broader ecoregions. Environ Toxicol Chem 2023;42:914–927. © 2023 SETAC [ABSTRACT FROM AUTHOR]

The widespread applications of graphene family nanomaterials (GFNs) raised the considerable concern over human health and environment. The cyto-genotoxic potentiality of GFNs has attracted much more attention, albeit the potential effects on the cellular epigenome remain largely unknown. The effects of GFNs on cellular genome were evaluated with single and double stranded DNA damage and DNA repair gene expressions while the effects on epigenome was accomplished by addressing the global DNA methylation and expression of DNA methylation machineries at non-cytotoxic to moderately cytotoxic doses in in vitro system. We used five different representatives of GFNs-pristine (GNP-Prist), carboxylated (GNP-COOH) and aminated (GNP-NH2) graphene nanoplatelets as well as single layer (SLGO) and few layer (FLGO) graphene oxide. The order of single stranded DNA damage was observed as GNP-Prist ≥ GNP-COOH > GNP-NH 2 ≥ FLGO > SLGO at 10 mg/L and marked dose dependency was found in SLGO. The GFNs possibly caused genotoxicity by affecting nucleotide excision repair and non-homologus end joining repair systems. Besides, dose dependent increase in global DNA methylation (hypermethylation) were observed in SLGO/FLGO exposure and conversely, GNPs treatment caused hypomethylation following the order as GNP-COOH > GNP-NH2 ≥ GNP-Prist. The decrements of DNA methyltransferase ( DNMT3B gene) and methyl-CpG binding domain protein ( MBD1 ) genes were probably the cause of global hypomethylation induced by GNPs. Conversely, the de novo methylation through the up-regulation of DNMT3B and MBD1 genes gave rise to the global DNA hypermethylation in SLGO/FLGO treated cells. In general, the GFNs induced genotoxicity and alterations of global DNA methylation exhibited compounds type specificity with differential physico-chemical properties. Taken together, our study suggests that the GFNs could cause more subtle changes in gene expression programming by modulating DNA methylation status and this information would be helpful for their prospective use in biomedical field. [ABSTRACT FROM AUTHOR]