Growth-dependent haemolymph physiology in freshwater crayfish farmed in Western Australia

Five experiments on crayfish under laboratory and outdoor field conditions were conducted to (1) establish relationships between moult stages and haemolymph osmolality (2) evaluate the interactions among size-dependent haemolymph ionic profile and physiology, feed ingestion and foregut evacuation rate and (3) evaluate the effects of abiotic and abiotic factors on the productivity of yabby populations. Moult stages significantly affected the haemolymph physiology, growth and health status. Zooplankton density and phosphorus influenced the yabby productivity

Nonparametric estimation of the fragmentation kernel based on a PDE stationary distribution approximation

We consider a stochastic individual-based model in continuous time to describe a size-structured population for cell divisions. This model is motivated by the detection of cellular aging in biology. We address here the problem of nonparametric estimation of the kernel ruling the divisions based on the eigenvalue problem related to the asymptotic behavior in large population. This inverse problem involves a multiplicative deconvolution operator. Using Fourier technics we derive a nonparametric estimator whose consistency is studied. The main difficulty comes from the non-standard equations connecting the Fourier transforms of the kernel and the parameters of the model. A numerical study is carried out and we pay special attention to the derivation of bandwidths by using resampling

A Study on Derailment at Railway Turnout Using the Multi-body Dynamics Simulation

In this study, the locomotive and the turnout were simulated with three-dimensional models. The purpose of this study is prediction the derailment phenomenon of the locomotive running on the turnout in Vietnam. Multi-body simulations were implemented by SIMPACK software to determine the derailment coefficient, the wheel unloading factor, and the lateral force. The interaction between the locomotive and the track structure at turnout was considered unified. The derailment coefficient, the wheel unloading factor, and the lateral force were calculated for locomotive-D19E at turnout (tg0.15) for 1000 mm gauge according to QCVN 18:2011/BGTVT, EN 14363:2016, and TCVN 8784:2011. The derailment coefficient, the wheel unloading factor, and the lateral force for the locomotive at max speed V=27.8 km/h are 0.94, 0.61, and 67.46 kN, respectively. These results show that the locomotive will not derail when it passes the turnout at a speed V 27.8 km/h

A Study on Derailment at Railway Turnout Using the Multi-body Dynamics Simulation

In this study, the locomotive and the turnout were simulated with three-dimensional models. The purpose of this study is prediction the derailment phenomenon of the locomotive running on the turnout in Vietnam. Multi-body simulations were implemented by SIMPACK software to determine the derailment coefficient, the wheel unloading factor, and the lateral force. The interaction between the locomotive and the track structure at turnout was considered unified. The derailment coefficient, the wheel unloading factor, and the lateral force were calculated for locomotive-D19E at turnout (tg0.15) for 1000 mm gauge according to QCVN 18:2011/BGTVT, EN 14363:2016, and TCVN 8784:2011. The derailment coefficient, the wheel unloading factor, and the lateral force for the locomotive at max speed V=27.8 km/h are 0.94, 0.61, and 67.46 kN, respectively. These results show that the locomotive will not derail when it passes the turnout at a speed V 27.8 km/h

The influence of scalar unparticle on the production of multiple photons in the Randall- Sundrum model

The influence of scalar unparticle on the production of multiple photons in the Randall- Sundrum model at muon colliders with the center of mass energy $\sqrt{s} = 3 - 10$ TeV is evaluated in detail. The results indicate that the total cross-sections depend strongly on the polarization of the muon and antimuon beams, the collision energy $\sqrt{s}$, the scaling dimension $d_{U}$ of the unparticle operator $\mathcal{O}_{U}$ and the energy scale $\Lambda_{U}$. Numerical evaluation shows that the cross - sections for the production of four - photons at the final state are much larger than the associated production of two - photons with the unparticle under the same conditions.Comment: 13 figures, 1 table. arXiv admin note: text overlap with arXiv:1807.0045

Improving the reliability of system for secure information trasmission

Запропоновано спосіб підвищення надійності систем прихованої передачі інформації з використанням синхронізованих генераторів хаосу на базі тунельних діодів. Розглянуто особливості зміни параметрів хаотичного сигналу для підвищення ступеня скритності інформації.The proposed method aims to improve the reliability of the system of secure information transmission using synchronized chaos generators on the basis of tunnel diodes. The features of changes of the parameters of the chaotic signal should be considered in order to increase the degree of the secretiveness of information.Предложено способ повышение надежности систем скрытой передачи информации с использованием синхронизированных генераторов хаоса на базе туннельных диодов. Рассмотрены особенности изменения параметров хаотического сигнала для повышения степени скрытности информации

Preschool STEM Activities and Associated Outcomes: A Scoping Review

This review highlights the need for further investigation into the benefits of STEM activities in preschool children’s learning, girls’ engagement and learning of children with disabilities in the STEM field. The review process involved accessing 19 relevant studies from Scopus, ERIC and Google Scholar databases in March 2023. Through the synthesis of information from these studies, seven STEM activities were identified as effective in enhancing preschool children’s learning: educational robots, educational games, argumentative interactions, inquiry-based learning and engineering design, drawing and telling about engineers, free play and pretend play, and group membership. Each of these activities contributes to different learning outcomes for children. Moreover, the review emphasizes the importance of role-playing activities ‘as if’ engineers and scientists, facilitated by teachers, in fostering girls’ motivation and engagement in the STEM field from an early age. Long-term scientific interventions at home have a significant positive impact on the science literacy skills of deaf children. The implications of this review are particularly relevant for early childhood educators, as it provides valuable insights into the use of STEM activities to enhance children’s learning outcomes

Linking Ethical Leadership to Employee Creative Performace: The Role of Leader-Member Exchange and Work Engagement

Purpose: The purpose of this research is to investigate the mediating role of leader-member exchange (LMX) and work engagement in the relationship between ethical leadership and creative performance.   Theoretical framework: The study is based on the theoretical foundation that ethical leadership positively influences creative performance. It further posits that this relationship is mediated by both leader-member exchange (LMX) and work engagement.   Design/Methodology/Approach: Data for this study was collected from a Vietnamese service firm, with a sample comprising 78 leaders and 354 employees. The collected data was analyzed using structural equation modeling (SEM) to examine the proposed relationships.   Findings: The findings of the study indicate a significant and positive correlation between ethical leadership and creative performance. Additionally, the study reveals that ethical leadership exerts an influence on both leader-member exchange (LMX) and work engagement, which subsequently enhance employees' demonstration of creativity in their work.   Research, practical & social implications: This research sheds light on the mediating mechanisms through which ethical leadership impacts creative performance. The findings highlight the importance of fostering positive leader-member relationships and promoting work engagement in order to enhance employees' creative behaviors. Practically, the study suggests that organizations should prioritize the development of ethical leadership qualities to foster a creative work environment. Moreover, the research contributes to the broader social implications by emphasizing the significance of ethical leadership in promoting creativity and innovation within organizations.   Originality/Value: This research contributes to the existing literature by examining the mediating role of leader-member exchange and work engagement in the relationship between ethical leadership and creative performance. The study provides valuable insights into the mechanisms through which ethical leaders can enhance creativity in the workplace. The findings of this research contribute to the understanding of the importance of ethical leadership and its impact on organizational outcomes, thereby adding to the originality and value of the study

The experience of using e-commerce platforms affects the online purchase intention of customers in the FMCG (Fast moving consumer goods) sector in Hanoi city

In recent times, the Vietnamese e-commerce market is in a period of strong development, in addition, to the sharp increase in people’s demands to join e-commerce platforms after the epidemic. The research group started with an overview study, then research hypotheses and models were proposed. After conducting preliminary qualitative and quantitative research to adjust the appropriate scales, the research group created a questionnaire and collected data in online forms with a sample size of 350. Next, the data was entered into the software for SEM analysis. The results of the study indicate that the quality of the e-commerce platform has an indirect impact on the purchase intention through the positive impact on the trust and the negative impact on the perceived risk. Attitudes towards information, trust, perceived risk, and perceived usefulness have direct influences on purchase intention. Attitude towards information, trust, and perceived usefulness have positive effects on purchase intention, while perceived risk harms purchase intention. In addition, purchase intention is relatively strongly influenced by trust and perceived usefulness. Perceived risk and attitude towards information have little influence on purchase intention. Finally, the research team proposes some solutions for businesses to increase the purchase intention of consumers through e-commerce platforms. &nbsp