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Feasibility of a Sprague–Dawley Rat Model for investigating the effects of seated whole-body vibration
No full textVehicular whole-body vibration (WBV) can have long-term adverse effects on human quality of life. Animal models can be used to study pathophysiologic effects of vibration. The goal of this study was to assess animal cooperation and well-being to determine the feasibility of a novel seated rat model for investigating the effects of WBV on biologic systems. Twenty-four male Sprague–Dawley rats were used. The experiment consisted of an acclimation phase, 2 training phases (TrP1 and TrP2), and a testing phase (TeP), including weekly radiographic imaging. During acclimation, rats were housed in pairs in standard cages without vibration. First, experimental (EG; n = 18) and control group 1 (C1; n = 3) rats were placed in a vibration apparatus without vibration, with increasing duration over 5 d during TrP1. EG rats were exposed to vertical random WBV that was increased in magnitude over 5 d during TrP2 until reaching the vibration signal used during TeP (15 min, 0.7 m·s−2 root mean square, unweighted). C1 rats were placed in the vibration apparatus but received no vibration during any phase. Control group 2 (C2; n = 3) rats remained in the home cages. Cooperation was evaluated with regard to rat-apparatus interactions and position compliance. Behavior, weight, and fecal glucocorticoid metabolite concentrations (fGCM) were used to evaluate animal well-being. We observed good cooperation and no behavioral patterns or weight loss between phases, indicating little or no animal stress. The differences in fGCM concentration between groups indicated that the EG rats had lower stress levels than the control rats in all phases except TrP1. Thus, this model elicited little or no stress in the conscious, unrestrained, seated rats
Unveiling novel Neocosmospora species from Thai mangroves as potent biocontrol agents against Colletotrichum species
Get PDFAims:
Neocosmospora species are saprobes, endophytes, and pathogens belonging to the family Nectriaceae. This study aims to investigate the taxonomy, biosynthetic potential, and application of three newly isolated Neocosmospora species from mangrove habitats in the southern part of Thailand using phylogeny, bioactivity screening, genome sequencing, and bioinformatics analysis.
Methods and results:
Detailed descriptions, illustrations, and a multi-locus phylogenetic tree with large subunit ribosomal DNA (LSU), internal transcribed spacer (ITS), translation elongation factor 1-alpha (ef1-α), and RNA polymerase II second largest subunit (RPB2) regions showing the placement of three fungal strains, MFLUCC 17–0253, MFLUCC 17–0257, and MFLUCC 17–0259 clustered within the Neocosmospora clade with strong statistical support. Fungal crude extracts of the new species N. mangrovei MFLUCC 17–0253 exhibited strong antifungal activity to control Colletotrichum truncatum CG-0064, while N. ferruginea MFLUCC 17–0259 exhibited only moderate antifungal activity toward C. acutatum CC-0036. Thus, N. mangrovei MFLUCC 17–0253 was sequenced by Oxford nanopore technology. The bioinformatics analysis revealed that 49.17 Mb genome of this fungus harbors 41 potential biosynthetic gene clusters.
Conclusion:
Two fungal isolates of Neocosmospora and a new species of N. mangrovei were reported in this study. These fungal strains showed activity against pathogenic fungi causing anthracnose in chili. In addition, full genome sequencing and bioinformatics analysis of N. mangrovei MFLUCC 17–0253 were obtained
Is adults’ ability to interpret iconicity shared between the spoken and gestural modalities?
No full textIconicity (the resemblance between form and meaning) exists in various modes of communication. This study investigated whether adults interpret iconicity in speech and gesture via a modality-independent ability. We tested 348 adult participants and assessed their ability to use iconic prosody and iconic gesture cues when interpreting novel verb meanings. We manipulated the rate of the spoken novel verbs (iconic prosody) and the rate of observed hand movements (iconic gestures) to be either fast or slow in two verb-action matching tasks. Adults could use these iconic speed cues to interpret novel verbs as referring to a fast or slow version of the same action. Adults showed similar performances in the two verb-action matching tasks: those who performed well in the iconic prosody task also performed well in the iconic gesture task. This positive correlation persisted even after controlling verbal working memory. Thus, we conclude that adults possess a modality-independent ability for interpreting iconicity
Solute effects on growth restriction in dilute ferrous alloys
Get PDFThe effect of dilute solute additions on growth restriction in binary ferrous alloys has been assessed by means of the heuristic growth restriction parameter (β) modelling framework (Fan et al. in Acta Mater. 152, 248–257, 2018). The CALPHAD (CALculation of PHAse Diagrams) methodology (Kaufman and Bernstein in Computer Calculation of Phase Diagrams, 1970) has been used to calculate β values from the liquidus slope m and the equilibrium distribution coefficient k values, at first approximation, in conjunction with the liquid-to-solid fraction to obtain true β values. Critical solute concentrations, below which solidification becomes partitionless, have also been calculated. Among 23 dilute binary ferrous alloy systems investigated, the five most efficient solutes on grain refinement are B, Y, O, S and C. A negative correlation, or inverse relationship, was observed between the true β values and the grain size values obtained from a study on experimental multicomponent dilute ferrous alloy systems (Li et al. in Metall. Mater. Trans. A 49 A, 2235–2247, 2018)
AI-enhanced cloud-edge-terminal collaborative network : survey, applications, and future directions
No full textThe cloud-edge-terminal collaborative network (CETCN) is considered as a novel paradigm for emerging applications owing to its huge potential in providing low-latency and ultra-reliable computing services. However, achieving such benefits is very challenging due to the heterogeneous computing power of terminal devices and the complex environment faced by the CETCN. In particular, the high-dimensional and dynamic environment states cause difficulties for the CETCN to make efficient decisions in terms of task offloading, collaborative caching and mobility management. To this end, artificial intelligence (AI), especially deep reinforcement learning (DRL) has been proven effective in solving sequential decision-making problems in various domains, and offers a promising solution for the above-mentioned issues due to several reasons. Firstly, accurate modelling of the CETCN, which is difficult to obtain for real-world applications, is not required for the DRL-based method. Secondly, DRL can effectively respond to high-dimensional and dynamic tasks through iterative interactions with the environment. Thirdly, due to the complexity of tasks and the differences in resource supply among different vendors, collaboration is required between different vendors to complete tasks. The multi-agent DRL (MADRL) methods are very effective in solving collaborative tasks, where the collaborative tasks can be jointly completed by cloud, edge and terminal devices which provided by different vendors. This survey provides a comprehensive overview regarding the applications of DRL and MADRL in the context of CETCN. The first part of this survey provides a depth overview of the key concepts of the CETCN and the mathematical underpinnings of both DRL and MADRL. Then, we highlight the applications of RL algorithms in solving various challenges within CETCN, such as task offloading, resource allocation, caching and mobility management. In addition, we extend discussion to explore how DRL and MADRL are making inroads into emerging CETCN scenarios like intelligent transportation system (ITS), the industrial Internet of Things (IIoT), smart health and digital agriculture. Furthermore, security considerations related to the application of DRL within CETCN are addressed, along with an overview of existing standards that pertain to edge intelligence. Finally, we list several lessons learned in this evolving field and outline future research opportunities and challenges that are critical for the development of the CETCN. We hope this survey will attract more researchers to investigate scalable and decentralized AI algorithms for the design of CETCN
Students' mental health during the pandemic : results of the observational cross-sectional COVID-19 MEntal health inTernational for university Students (COMET-S) study
No full textIntroduction: The aim of the study was to search rates of depression and mental health in university students, during the COVID-19 pandemic. Materials and methods: This is an observational cross-sectional study. A protocol gathering sociodemographic variables as well as depression, anxiety and suicidality and conspiracism was assembled, and data were collected anonymously and online from April 2020 through March 2021. The sample included 12,488 subjects from 11 countries, of whom 9,026 were females (72.2%; aged 21.11 ± 2.53), 3,329 males (26.65%; aged 21.61 ± 2.81) and 133 “non-binary gender” (1.06%; aged 21.02 ± 2.98). The analysis included chi-square tests, correlation analysis, ANCOVA, multiple forward stepwise linear regression analysis and Relative Risk ratios. Results: Dysphoria was present in 15.66% and probable depression in 25.81% of the total study sample. More than half reported increase in anxiety and depression and 6.34% in suicidality, while lifestyle changes were significant. The model developed explained 18.4% of the development of depression. Believing in conspiracy theories manifested a complex effect. Close to 25% was believing that the vaccines include a chip and almost 40% suggested that facemask wearing could be a method of socio-political control. Conspiracism was related to current depression but not to history of mental disorders. Discussion: The current study reports that students are at high risk for depression during the COVID-19 pandemic and identified specific risk factors. It also suggested a role of believing in conspiracy theories. Further research is important, as it is targeted intervention in students' groups that are vulnerable both concerning mental health and conspiracism
Resilient machine learning : advancement, barriers and opportunities in the nuclear industry
No full textThe widespread adoption and success of Machine Learning (ML) technologies depend on thorough testing of the resilience and robustness to adversarial attacks. The testing should focus on both the model and the data. It is necessary to build robust and resilient systems to withstand disruptions and remain functional despite the action of adversaries, specifically in the security-sensitive industry like the Nuclear Industry (NI) where consequences can be fatal in terms of both human lives and assets. We analyse ML based research works that have investigated adversaries and defence strategies in the NI. We then present the progress in the adoption of ML techniques, identify use cases where adversaries can threaten the ML-enabled systems and finally identify the progress on building Resilient Machine Learning (rML) systems entirely focusing on the NI domain
Adaptive fuzzy practical bipartite synchronization for multi-agent systems with intermittent feedback under multiple unknown control directions
No full textIn this article, we propose an adaptive fuzzy control design for the distributed competitive control problem of multiagent systems (MASs) with multiple unknown control directions. The bipartite synchronization control is investigated by using the fuzzy backstepping control framework and fuzzy logic systems. To broaden the application field for the distributed protocol design, we consider practical bipartite synchronization for a group of MASs consisting of followers subject to heterogeneous unknown control directions. To address these multiple unknown control directions, a novel Nussbaum-type function is developed. Moreover, to reduce the communication bandwidth, this article proposes two threshold strategies for event-triggered control to avoid any unnecessary sampling while taking flexibility into consideration, further improving the efficiency and feasibility of the developed bipartite protocol design. The experimental results indicate that the proposed control method can effectively realize bipartite synchronization of MASs with multiple unknown control directions
Intercultural learning and identity development as a form of teacher development through study abroad : narratives from English language practitioners
No full textThe spread of English and its increasing importance in intercultural encounters have challenged essentialist perspectives of culture in English language teaching. In addition to using English as a means of communication, students are expected to develop intercultural awareness, which allows them to analyse and reflect on their intercultural encounters and to participate in social activities. Such a need draws great attention to language teachers’ perceptions of and engagement in intercultural teaching. As a narrative inquiry, this paper examines the reflections of English language practitioners who have returned from an overseas study experience and have become English language teachers in China. It focuses on their study abroad experiences, encompassing both their achievements and challenges in the context of intercultural learning, and examines how these experiences have influenced their current involvement in intercultural teaching. The findings help shed light on the shifts in teachers’ perceptions of intercultural encounters and how the processes of making sense of intercultural experiences inform their orientation towards intercultural learning. The paper considers the importance of helping teachers use their experiential understanding of language and culture to generate a critical pedagogical stance to promote intercultural education
Developmental associations between motor and communication outcomes in Fragile X syndrome : variation in the context of co-occurring autism
No full textFragile X syndrome (FXS), the leading heritable cause of intellectual disability, has a co-occurrence rate of autism spectrum disorder (ASD) estimated at ~60%. The onset and rates of motor development in FXS are slower relative to neurotypical development, and even more so in the context of co-occurring FXS + ASD. Extant evidence suggests these differences are likely to affect communication, yet this developmental process or how it varies in the context of co-occurring ASD remains unknown in FXS. We aimed to delineate developmental associations between early motor abilities and their rate of development from 9 to 60 months of age on communication outcomes in 51 children with FXS, 28 of whom had co-occurring ASD. We also aimed to identify variation in these developmental associations in the context of co-occurring ASD. Results captured within-syndrome variability in these developmental associations as a function of co-occurring ASD. Fine motor proved to be a robust predictor of receptive communication regardless of co-occurring ASD, but we identified differences between FXS with and without ASD in the association between aspects of motor development and expressive outcomes. Findings provide evidence for differential developmental processes in the context of co-occurring ASD with implications for timely developmental intervention. Lay abstract Fragile X syndrome (FXS), the leading heritable cause of intellectual disability, has a co-occurrence rate of autism spectrum disorder (ASD) estimated at ~60%. Children with FXS experience delayed achievement and slower development of key motor abilities, which happens to an even greater extent for children with both FXS and ASD. A multitude of studies have demonstrated that motor abilities are foundational skills related to later communication outcomes in neurotypical development, as well as in the context of ASD. However, these associations remain unexamined in FXS, or FXS + ASD. In this study, we aimed to determine the associations between early motor skills and their rate of development on communication outcomes in FXS. Furthermore, we investigated whether these associations varied in the context of co-occurring FXS + ASD. Results revealed within-FXS variation in the context of co-occurring ASD between some aspects of motor development and communication outcomes, yet within-FXS consistency between others. Findings provide evidence for variability in developmental processes and outcomes in FXS in the context of co-occurring ASD and offer implications for intervention