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Exploring mixotrophy of dinoflagellate species is critical to understanding red-tide dynamics and dinoflagellate evolution. Some species in the dinoflagellate genus Karenia have caused harmful algal blooms. Among 10 Karenia species, the mixotrophic ability of only two species, Karenia mikimotoi and Karenia brevis, has been investigated. These species have been revealed to be mixotrophic; however, the mixotrophy of the other species should be explored. Moreover, although K. mikimotoi was previously known to be mixotrophic, only a few potential prey species have been tested. We explored the mixotrophic ability of Karenia bicuneiformis, Karenia papilionacea, and Karenia selliformis and the prey spectrum of K. mikimotoi by incubating them with 16 potential prey species, including a cyanobacterium, diatom, prymnesiophyte, prasinophyte, raphidophyte, cryptophytes, and dinoflagellates. Cells of K. bicuneiformis, K. papilionacea, and K. selliformis did not feed on any tested potential prey species, indicating a lack of mixotrophy. The present study newly discovered that K. mikimotoi was able to feed on the common cryptophyte Teleaulax amphioxeia. The phylogenetic tree based on the large subunit ribosomal DNA showed that the mixotrophic species K. mikimotoi and K. brevis belonged to the same clade, but K. bicuneiformis, K. papilionacea, and K. selliformis were divided into different clades. Therefore, the presence or lack of a mixotrophic ability in this genus may be partially related to genetic characterizations. The results of this study suggest that Karenia species are not all mixotrophic, varying from the results of previous studies.

The mortality rate of red-tide dinoflagellates owing to predation is a major parameter that affects their population dynamics. The dinoflagellates Ansanella granifera and Ansanella sp. occasionally cause red tides. To understand the interactions between common heterotrophic protists and A. granifera, we explored the feeding occurrence of nine heterotrophic protists on A. granifera and the growth and ingestion rates of the heterotrophic dinoflagellate Gyrodinium dominans on A. granifera as a function of prey concentration and those of Oxyrrhis marina at a single high prey concentration. The heterotrophic dinoflagellates Aduncodinium glandula, G. dominans, Gyrodinium moestrupii, Luciella masanensis, Oblea rotunda, O. marina, Polykrikos kofoidii, and Pfiesteria piscicida and the naked ciliate Strombidium sp. were able to feed on A. granifera. With increasing mean prey concentrations, the growth and ingestion rates of G. dominans feeding on A. granifera rapidly increased and became saturated or slowly increased. The maximum growth and ingestion rates of G. dominans on A. granifera were 0.305 d-1 and 0.42 ng C predator-1 d-1 (3.8 cells predator-1 d-1), respectively. Furthermore, the growth and ingestion rates of O. marina on A. granifera at 1,700 ng C mL-1 (15,454 cells mL-1) were 0.037 d-1 and 0.19 ng C predator-1 d-1 (1.7 cells predator-1 d-1), respectively. The growth and ingestion rates of G. dominans and O. marina feeding on A. granifera were almost the lowest among those on the dinoflagellate prey species. Therefore, G. dominans and O. marina may prefer A. granifera less than other dinoflagellate prey species. The low mortality rate of A. granifera may positively affect its bloom formation.

Noctiluca scintillans is a heterotrophic dinoflagellate that causes red-colored oceans during the day (red tides) and glowing oceans at night (bioluminescence). This species feeds on diverse prey, including phytoplankton, heterotrophic protists, and eggs of metazoans. Thus, many scientists have conducted studies on the ecophysiology of this species. It is easy to cultivate N. scintillans at a scale of 100 L because N. scintillans cells usually stay near the surface, while prey cells stay below the surface in large water tanks. To obtain mass-cultured N. scintillans cells, we developed an automatic system for cultivating N. scintillans on a scale of 100 L. The system consisted of four tanks containing fresh nutrients, the chlorophyte Dunaliella salina as prey, N. scintillans for growth, and N. scintillans for storage, respectively. The light intensities supporting the high growth rates of D. salina and N. scintillans were 300 and 20 μmol photons m-2 s-1, respectively. Twenty liters of D. salina culture from the prey culture tank were transferred to the predator culture tank, and subsequently 20 L of nutrients from the nutrient tank were transferred to the prey culture tank every 2 d. When the volume of N. scintillans in the predator culture tank reached 90 L 6 d later, 70 L of the culture were transferred to the predator storage tank. To prevent N. scintillans cells from being separated from D. salina cells in the predator culture tank, the culture was mixed using an air pump, a sparger, and a stirrer. The highest abundance of N. scintillans in the predator culture tank was 45 cells mL-1, which was more than twice the highest abundance when this dinoflagellate was cultivated manually. This automatic system supplies 100 L of N. scintillans pure culture with a high density every 10 d for diverse experiments on N. scintillans.

Water temperature affects plankton survival and growth. The dinoflagellate Shimiella gracilenta survives using theplastids of ingested prey, indicating kleptoplastidy. However, studies on the effects of water temperature on kleptoplastidicdinoflagellates are lacking. We explored the growth and ingestion rates of S. gracilenta as a function of water temperature.Furthermore, using data on its spatiotemporal distribution in Korean coastal waters during 2015–2018, we predictedits distribution under elevated temperature conditions of +2, +4, and +6°C. Growth rates of S. gracilenta with andwithout Teleaulax amphioxeia prey as well as ingestion rates were significantly affected by water temperature. Growthrates of S. gracilenta with and without prey were positive or zero at 5–25°C but were negative at ≥30°C. The maximumgrowth rate of S. gracilenta with T. amphioxeia was 0.85 d-1, achieved at 25°C, and 0.21 d-1 at 20°C without prey. The ingestionrate of S. gracilenta on T. amphioxeia at 25°C (0.05 ng C predator-1 d-1) was greater than that at 20°C (0.04 ng Cpredator-1 d-1). Thus, feeding may shift the optimal temperature for the maximum growth rate of S. gracilenta from 20 to25°C. In spring and winter, the distributions of S. gracilenta under elevated temperature conditions were predicted notto differ from those during 2015–2018. However, S. gracilenta was predicted not to survive at some additional stationsunder elevated temperature conditions of +2, +4, and +6°C in summer or under elevated temperature conditions of +6°Cin autumn. Therefore, global warming may affect the distribution of S. gracilenta.

The study aimed to explore the associations between the psychosocial and organizational factors, job satisfaction, and mental well-being of schoolteachers. A further aim was to examine whether job satisfaction mediated the relationship between these factors and mental well-being. A cross-sectional design was used to collect data using a self-reported questionnaire. Six hundred and nine schoolteachers were included in the final analyses. The relationships between the variables were tested in a path analysis model. The data fit the hypothesized model well. The results demonstrated that organizational justice, efficacy beliefs, and school climate were significantly associated with job satisfaction and that the relationships between these variables and mental well-being were mediated by job satisfaction. The findings have implications for programs targeted at promoting teachers’ well-being.

Some species in the dinoflagellate genus Alexandrium are bioluminescent. Of the 33 formally described Alexandrium species, the bioluminescence capability of only nine species have been tested, and eight have been reported to be bioluminescent. The present study investigated the bioluminescence capability of seven Alexandrium species that had not been tested. Alexandrium mediterraneum, A. pohangense, and A. tamutum were bioluminescent, but A. andersonii, A. hiranoi, A. insuetum, and A. pseudogonyaulax were not. We also measured the bioluminescent intensity of A. affine, A. fraterculus, A. mediterraneum, A. ostenfeldii, A. pacificum, A. pohangense, A. tamarense, and A. tamutum. The mean 200-second-integrated bioluminescence intensity per cell ranged from 0.02 to 32.2 × 104 relative luminescence unit per cell (RLU cell-1), and the mean maximum bioluminescence intensity per cell per second (BLMax) ranged from 0.01 to 10.3 × 104 RLU cell-1 s-1-1. BLMax was significantly correlated with the maximum growth rates of Alexandrium species, except for A. tamarense. A phylogenetic tree based on large subunit ribosomal DNA (LSU rDNA) showed that the bioluminescent species A. affine, A. catenella, A. fraterculus, A. mediterraneum, A. pacificum, and A. tamarense formed a large clade. However, the toxicity or mixotrophic capability of these species was split. Thus, their bioluminescence capability in this clade was more consistent than their toxicity or mixotrophic capability. Phylogenetic trees based on LSU rDNA and the luciferase gene of Alexandrium were consistent except for A. pohangense. The results of the present study can provide a basis for understanding the interspecific diversity in bioluminescence of Alexandrium.

To explore the ecophysiological characteristics of the kleptoplastidic dinoflagellate Shimiella gracilenta, we determined its spatiotemporal distribution in Korean coastal waters and growth and ingestion rates as a function of prey concentration. The abundance of S. gracilenta at 28 stations from 2015 to 2018 was measured using quantitative realtime polymerase chain reaction. Cells of S. gracilenta were detected at least once at all the stations and in each season, when temperature and salinity were 1.7–26.4°C and 9.9–35.6, respectively. Moreover, among the 28 potential prey species tested, S. gracilenta SGJH1904 fed on diverse prey taxa. However, the highest abundance of S. gracilenta was only 3 cells mL-1 during the study period. The threshold Teleaulax amphioxeia concentration for S. gracilenta growth was 5,618 cells mL-1, which was much higher than the highest abundance of T. amphioxeia (667 cells mL-1). Thus, T. amphioxeia was not likely to support the growth of S. gracilenta in the field during the study period. However, the maximum specific growth and ingestion rates of S. gracilenta on T. amphioxeia, the optimal prey species, were 1.36 d-1 and 0.04 ng C predator- 1 d-1, respectively. Thus, if the abundance of T. amphioxeia was much higher than 5,618 cells mL-1, the abundance of S. gracilenta could be much higher than the highest abundance observed in this study. Eurythermal and euryhaline characteristics of S. gracilenta and its ability to feed on diverse prey species and conduct kleptoplastidy are likely to be responsible for its common spatiotemporal distribution.

Given the challenges experienced by the Semai indigenous communities in Perak, Malaysia, and their distinct cultural beliefs, it is important to understand the role of the social and cultural networks in their resilience processes. In particular, further attention needs to be paid to how their families function and shape their beliefs about their lives, as there might be key mechanisms and processes that differ from existing general conceptualizations of family. This grounded theory analysis of 23 Semai Orang Asli (indigenous) community members established a model of the Semai’s family conceptualization and functioning. Findings revealed that the Semai’s concept of family encompasses an extensive network of individuals with their shared relationship with nyenang (spirit ancestors) and cultural heritage, which in turn leads them to have a deep sense of shared family identity and connectedness. This worldview guided the Semai’s family processes and functioning, captured by the following five dimensions: sharing obligations and responsibilities, making collective decisions, prioritizing community’s welfare, sharing of knowledge and resources, and willingness to work with everyone. These factors facilitate a conducive and supportive environment aimed at maintaining existing family relationships. This model can guide the development of culturally specific programs that promote and strengthen indigenous family relationships and resilience.

The key nutrient sources for red-tide species are freshwater and deep cold waters. However, a lack of data on their growth rates at different depths limits our understanding of the effects of deep cold waters on red-tide formation. Offshore water was collected from 0, 20, and 40 m in the South Sea of Korea and the growth rates of major red-tide species were measured after their addition to these waters. The growth rates of Margalefidinium polykrikoides in the waters from 0, 20, and 40 m (0.25, 0.25, and 0.21 d-1) were similar. The growth rates of Prorocentrum donghaiense, Tripos furca, and Alexandrium fraterculus in the water from 20 m (0.30, 0.37, and 0.42 d-1) were similar to those from 40 m but higher than those from 0 m (0.16, 0.04, and 0.21 d-1). The ability of P. donghaiense, T. furca, and A. fraterculus to reach deep waters is therefore a critical factor affecting red-tide formation. Considering their vertical migration depths and growth rates at different depths, P. donghaiense, T. furca, or A. fraterculus can dominate when deep waters are intruded to 10 m, while A. fraterculus or M. polykrikoides can dominate when deep waters retreat to 20 m. Only M. polykrikoides can dominate when deep waters retreat to 30 m. These scenarios are supported by the results recorded in the red-tide events of 2014. Red-tide species can thus be predicted using data on their growth rates at different depths, their vertical migration depths, and the position of deep cold waters.

The Coronavirus (COVID-19) national lockdowns profoundly affected the lives of many, as significant portions of the U.K. population were involuntarily sequestered away from their usual social landscapes into newfound states of solitude. Many millennials (those between the ages of 25 and 40 at the point of study), having lived in an age of constant connection, found themselves in an extended period of solitude for the first time. The current qualitative study explores through Interpretative Phenomenological Analysis (IPA) how some UK millennials were able to harness the unique self-transformative properties of positive solitude during the COVID-19 national lockdowns. Analysis revealed a narrative of self-discovery, as domains of positive solitude granted the participants freedom from the demands of performative social burdens and encouraged opportunities to engage with mindfulness and meaningful introspection. These activities, within the experience of solitude, encouraged an alignment of inward beliefs and outward behaviors for the participants, thus helping them to cultivate a more congruent self-concept and subsequently a heightened sense of authenticity and enhanced psychological well-being. Clinical implications leading on from the current study highlight the importance of mindfulness and other solitude-promoting interventions as a method to ameliorate depressive symptoms and improve psychological well-being.

A small dinoflagellate, ~13 μm in cell length, was isolated from Jinhae Bay, Korea. Light microscopy showed that it was similar to the kleptoplastidic dinoflagellate Gymnodinium gracilentum nom. inval. rDNA sequences were obtained and its anatomy and morphology described using light and scanning and transmission electron microscopy. Phylogenetic analyses indicated that it belonged to the family Kareniaceae. However, its large subunit (LSU) rDNA sequences were 5.2-9.5% different from those of the other five genera in the family, and its clade was clearly divergent from that of each genus. Its overall morphology was different from those of the other five genera in the family and from Gymnodinium. Unlike Gymnodinium, this dinoflagellate did not have a horseshoe-shaped apical groove, nuclear envelope chambers, or a nuclear fibrous connective (NFC). It had an apical line of narrow amphiesmal vesicles and an elongated apical furrow crossing the apex. Cells were covered with polygonal amphiesmal vesicles arranged in 16 rows. Starved cells did not contain their own plastids, eyespots, pyrenoids, peridinin, or fucoxanthin. However, they could survive without added prey for approximately one month using chloroplasts from the cryptophyte prey Teleaulax amphioxeia, indicating kleptoplastidy. Because this taxon is genetically distinct at the generic rank from the other genera in Kareniaceae, it is placed in Shimiella gen. nov., and because G. gracilentum was invalid, the new bionomial S. gracilenta sp. nov. is proposed.

Mental health practitioners in many developing countries are faced with high job demands and a lack of institutional support. Given their high levels of work-related stress, it is important to identify mechanisms that help them to maintain psychological well-being and job satisfaction. Recent research has focused on the role that positive orientation (POS) may play in mediating the negative impact of stress on individual well-being. The present study investigated whether POS predicts mental health practitioners' perceived levels of stress, mental health and job satisfaction. If POS measures a person's tendency to take a positive attitude to life and their ability to cope with difficulties, a high POS could be linked to reduced levels of stress and increased levels of job satisfaction and well-being. This study examined associations between self-reported POS and psychological outcomes in a sample of 100 Malaysian mental health practitioners. The results showed that POS significantly predicted job satisfaction positively and mental health issues and perceived stress negatively, even when socio-demographic variables were controlled. Overall, we found a strong effect of POS on individual functioning across the sample of mental health practitioners. Our results have implications for improving practitioner wellbeing and job satisfaction.

Dinoflagellates are a major component of marine ecosystems, and very cold and hot water may affect their survival. Global warming has amplified the magnitude of water temperature fluctuations. To investigate the molecular responses of dinoflagellates to very cold and hot water, we compared the differentially expressed genes of the phototrophic dinoflagellate Biecheleriopsis adriatica grown under optimal temperature and cold and heat stress. The number of genes upregulated or downregulated between optimal temperature and cold stress was twice than that between optimal temperature and heat stress. Moreover, the number of upregulated genes was greater than that of the downregulated genes under cold stress, whereas the number of upregulated genes was less than that of the downregulated genes under heat stress. Furthermore, among the differentially expressed genes, the number of genes upregulated under cold stress and with unchanged expression under heat stress was the highest, while the number of the genes downregulated under cold stress, but not under heat stress, was the second-highest. Facilitated trehalose transporter Tret1 and DnaJ-like subfamily B member 6-A were upregulated and downregulated, respectively, under cold stress; however, their expression remained unchanged under heat stress. In contrast, Apolipoprotein d lipocalin and Troponin C in skeletal muscle were upregulated and downregulated, respectively, under both cold and heat stress. This study provides insight into the genetic responses of dinoflagellates to climate change-driven large water temperature fluctuations.

In recent decades, organic semiconductors (OSCs), which are lightweight, flexible, and have low processing costs, have enabled significant progress in terms of efficiency in the field of organic electronics [e.g., as active materials in organic photovoltaics (OPVs), hole-transporting materials (HTMs) in perovskite solar cells (PSCs), and semiconducting materials in organic thin-film transistors (OTFTs)]. However, most OSCs are currently being processed in halogenated toxic solvents, which creates conditions that are hazardous to the human body and the environment. Accordingly, for large-area fabrication and commercialization, OSCs must be developed to show high solubility in environmentally friendly and non-harmful solvents as well as high performance. This review considers environmentally benign solvents and potential approaches for increasing the solubility of OSCs in relation to Hansen solubility parameters (HSPs) and molecular design. It also provides guidelines regarding molecular design for advanced OSCs possessing additional functions, sustaining green-solvent processability, and superior efficiency. We believe that these efforts toward an environmentally benign process will contribute to the development and commercialization of organic electronics and shed light on future directions for OSC research in relation to industry, the environment, and human life.

The phlorotannin compounds, dieckol and phlorofucofuroeckol (PFF), extracted from Ecklonia cava, have been suggested to exhibit anti-inflammatory, anti-adipogenic or anti-tumorigenic activity. However, role of dieckol or PFF in LPS/TLR-4 signaling that regulates cancer development still remains to be determined. Here we report that dieckol or PFF blocked lipopolysaccharide (LPS)-induced migration and invasion of human breast cancer MCF-7 or MDA-MB-231 cells by about 50% (p

Coronavirus disease 2019 (COVID-19) outbreak has led to the closure of schools and universities, which forced students to reorganize their daily and academic lives. The pandemic has thus impacted the well-being of students in various ways. This study aimed to investigate the relationship between the perceived employability, self-efficacy, ambition, organizational commitment, and career planning of students, as well as mental well-being, student engagement, and academic burnout during the pandemic. A total of 269 Italian university students participated in an online questionnaire. Our results highlight that students experienced high levels of uncertainty about their employability and career planning. In contrast, however, they reported healthy levels of mental well-being and student engagement, high career ambitions, and strong self-efficacy, despite the impact of COVID-19. We suggested that intervention and supportive programs should be offered to students over the long term in order to minimize the negative impact of the pandemic.

The aim of the work was to develop and validate the COVID-19 Risk Perception Scale (CoRP), a brief self-report questionnaire for individuals’ perceptions of risk in the COVID-19 pandemic. Two studies were conducted in order to evaluate the new scale’s psychometric properties. Study 1 included 269 Italian participants (77.3% female) to initially test the scale’s structure and construct validity. Study 2 involved 1061 (76.2% female) Italians aged 18 to 80 years old and examined the structure of the scale, construct validity, and age invariance. Exploratory and Confirmatory factor analyses confirmed the one-factor solution, and the structure of the scale was found to be invariant across age groups. The scale also demonstrated a high internal reliability. The CoRP correlated positively with the fear of COVID-19 scale, and low with the Impact of Event and distressing phenomena as measured by GHQ. The present work thus affirms that the CoRP is a valid instrument for measuring individuals’ risk perception of COVID-19.

Cyberbullying amongst adolescents is a rapidly growing and alarming global phenomenon that can significantly harm their well-being. Studying cyberbullying in East Asia is especially important, where peer pressure based on collectivistic ideals and rigid cultural scripts for social interactions remain strong. Furthermore, the countries represented in this review are amongst the top globally for internet usage, suggesting that adolescents in East Asia are likely to be excessive users of social media communication and be more exposed to various forms of cyberbullying. This systematic review summarizes findings from peer-reviewed journal articles and book chapters on cyberbullying amongst adolescents between the ages of 10 and 19 in East Asian countries (N = 21). SCOPUS, Google Scholar, and PsycINFO databases were searched for relevant work published between 2008 and 2020. Search strategies involved using keywords related to cyberbullying, adolescents, East Asia, and the name of each country represented in the region (China, South Korea, Japan, Hong Kong and Taiwan). Key factors associated with cyberbullying specific to adolescents in this region are identified and discussed in this review, such as gender socialization patterns and literacy with digital media communication, emphasis on academic achievement and school factors, urban-rural digital divide, relationship with parents and teachers, and collectivistic values. The present review highlights the need to pay further attention to the sociocultural context in future cyberbullying research and calls for more context-specific cyberbullying prevention programs and awareness initiatives.

Naphthalene diimide (NDI)-based copolymers are promising polymer acceptors in all-polymer solar cells (all-PSCs), but their large crystal domains cause large-scale phase separation in all-polymer blend films. This limits the photovoltaic performance and mechanical stability of all-PSCs. Herein, we control all-polymer blend films by introducing a fluorinated copolymer of NDI and (E)-1,2-bis(3-fluorothiophen-2-yl)ethene (FTVT) (PNDI–FTVT) as a polymer acceptor for flexible all-PSCs. The copolymer PNDI–FTVT has a less crystalline structure and higher electron mobility than its nonfluorinated copolymer counterpart (PNDI–TVT). A blended film incorporating PNDI–FTVT exhibits a well-mixed morphology and improves the chain interconnectivity with a polymer donor, providing better charge transport pathways and enhanced mechanical resilience. The PNDI–FTVT-based flexible all-PSC exhibits enhanced photovoltaic performance in comparison with a PNDI–TVT-based flexible all-PSC (5.11–7.14%) as well as excellent mechanica...

The purpose of this article is to argue for the deconstruction rather than the decolonisation of the neocolonial curriculum. Globalisation facilitates the democratisation of higher education, which is now accessible to more people than ever before, but globalisation also facilitates the expansion of the ideological dominance of the Global North over the Global South by means of the neocolonial curriculum. Contemporary attempts to decolonise Global South curricula are proceeding very slowly. We propose an alternative, the deconstruction of the Global North curriculum, i.e. a radical change to the Global North curriculum that exploits the neoliberal imperative to maximise profit in order to undermine the neocolonial curriculum. We use two case studies – Frantz Fanon and Çiğdem Kağitçibaşi – to demonstrate how the deconstruction of the Global North curriculum can be achieved, by the prioritisation of theory and practice that are sensitive to context.

Background: The emphasis of education within the collectivistic Malaysian culture has exposed Malaysian university students to high levels of academic stressors. The experience of stress that stems from the experience of such stressors can be positive (eustress) or negative (distress). However, the presence of adaptive abilities to academic stress may influence the experience of stress. The present study examines psychological capital as the adaptive ability to academic stress among a collectivistic Malaysian university student sample. Methods: This cross-sectional study was conducted with a total of 183 students from a university in Malaysia. Findings: Analyses showed that university students with high academic distress did not predict low academic performance; while, university students with high academic eustress predicted high academic performance. Psychological capital was found to mitigate the influence of academic distress on academic performance but not on the influence of academic eustress on academic performance. Conclusion: The study debunked the common misconceptions about academic stress. It highlighted that the experience of eustress and the presence of psychological capital may be an important resource for students’ stress coping.

Values, political beliefs, and family perceptions are sensitive to cultural change, which embraces change in the political, economic, and other societal-level spheres. This study investigated the impact of culture-level individualism and gender on family perceptions and the interrelations between the macro-level and individual level factors in South Korea and Hungary, two countries that have undergone recent social change. The study included data from 288 university students. Cultural and gender influences on Postmodernist values, democratic beliefs, political interest, political conservatism, perceptions of family relatedness and democratisation were found, and the overall model of interrelations between all the variables was tested using SEM (structural equation modelling) analysis.