Search results for: growth dynamics

Authors: Mitchell J. Baum, Badin Gibbes, Greg Collecutt

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This study details a three-dimensional field-scale numerical investigation conducted for the Gold Coast Desalination Plant (GCDP) offshore multiport brine diffuser. Quantitative assessment of diffuser performance with regard to trajectory, dilution and mapping of seafloor concentration distributions was conducted for 100% plant operation. The quasi-steady Computational Fluid Dynamics (CFD) simulations were performed using the Reynolds averaged Navier-Stokes equations with a k-ω shear stress transport turbulence closure scheme. The study compliments a field investigation, which measured brine plume characteristics under similar conditions. CFD models used an iterative mesh in a domain with dimensions 400 m long, 200 m wide and an average depth of 24.2 m. Acoustic Doppler current profiler measurements conducted in the companion field study exhibited considerable variability over the water column. The effect of this vertical variability on simulated discharge outcomes was examined. Seafloor slope was also accommodated into the model. Ambient currents varied predominantly in the longshore direction – perpendicular to the diffuser structure. Under these conditions, the alternating port orientation of the GCDP diffuser resulted in simultaneous subjection to co-propagating and counter-propagating ambient regimes. Results from quiescent ambient simulations suggest broad agreement with empirical scaling arguments traditionally employed in design and regulatory assessments. Simulated dynamic ambient regimes showed the influence of ambient crossflow upon jet trajectory, dilution and seafloor concentration is significant. The effect of ambient flow structure and the subsequent influence on jet dynamics is discussed, along with the implications for using these different simulation approaches to inform regulatory decisions.

Keywords: computational fluid dynamics, desalination, field-scale simulation, multiport brine diffuser, negatively buoyant jet

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Authors: Serier Bouchenak NORA, Bouguerni ABDELMADJID

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Algeria is a Mediterranean country which provides an ideal habitat for a wide range of species of medicinal plants. The objective of this current work is to extract the gel contained in the leaves of Aloe vera in order to formulate an oral gel as a prebiotic and see its effects on probiotics (lactic and pseudo lactic bacteria and bifido bacterium). Aloe vera polysaccharid extract is a matrix mainly composed of non-digestible oligosaccharids or slow-fermentation polysaccharids, as this produces a lower pH. The behavior of Aloe vera during in vitro fermentation of the colon was similar to that of lactulose, indicating the possibility of using Aloe vera and its polysaccharids extracts as a prebiotic. The microbiological control of the two kinds of bacteria (bifidobacteria and staphylococci) has demonstrated the gel capacity to stimulate them by these bioactive compounds. The generation time of Bifidobacteria in fermented milk with added prebiotic Aloe vera gel is 80.408 min with a µ growth rate equal to 0.012 min -1. The doubling time is 61.459 min with a growth rate µ equal to 0.016 min -1 for the Streptococcus sp. species.

Keywords: aloe vera, probiotics, prebiotics, growth rate, bifidobacteria

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Authors: Sami Ali Metwally, Bedour Helmy Abou-Leila, Hussien Ibrahim Abdel-Shafy

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This study was carried out at the pilot plant area in the National Research Centre during the two successive seasons, 2020 and 2022. The aim is to investigate the response of vegetative growth and chemical constituents of sunflowers plants irrigated by two types of wastewater, namely: black wastewater W1 (Bathroom) and grey wastewater W1, under irradiation conditions of helium-neon (He-Ne) laser. The examined data indicated that irrigation of W1 significantly increased the growth and flowering parameters (plant height, leaves number, leaves area, leaves fresh and dry weight, flower diameter, flower stem length, flower stem thickness, number of days to flower, and total chlorophyll). Treated sunflower plants with 0 to 10 min. recorded an increase in the fresh weight and dry weight of leaves. However, the superiority of increasing vase life and delaying flowers were recorded by prolonging exposure time by up to 10 min. Regarding the effect of interaction treatments, the data indicated that the highest values on almost growth parameters were obtained from plants treated with W1+0 laser followed by W2+10 min. laser, compared with all interaction treatments. As for flowering parameters, the interactions between W2+2 min. time exposure, W1+0 time, w1+10 min., and w1+2 min. exposures recorded the highest values on flower diameter, flower stem length, flower stem thickness, vase life, and delaying flowering.

Keywords: greywater, sunflower plant, water reuse, vegetative growth, laser radiation

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Authors: Saeed Khandan Siar, Stefan Tenbohlen, Christian Breuer, Raphael Lebreton

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The goal of this article is to investigate the detailed temperature distribution and the fluid flow of an oil cooled winding of a power transformer by means of computational fluid dynamics (CFD). The experimental setup consists of three passes of a zig-zag cooled disc type winding, in which losses are modeled by heating cartridges in each winding segment. A precise temperature sensor measures the temperature of each turn. The laboratory setup allows the exact control of the boundary conditions, e.g. the oil flow rate and the inlet temperature. Furthermore, a simulation model is solved using the open source computational fluid dynamics solver OpenFOAM and validated with the experimental results. The model utilizes the laminar and turbulent flow for the different mass flow rate of the oil. The good agreement of the simulation results with experimental measurements validates the model.

Keywords: CFD, conjugated heat transfer, power transformers, temperature distribution

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Authors: Yong Eun Yoon, Eric N. Johnson, Liling Ren

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Multirotor is one of the most popular types of small unmanned aircraft systems and has already been used in many areas including transport, military, surveillance, and leisure. Together with its popularity, the needs for proper flight control is growing because in most applications it is required to conduct its missions autonomously, which is in many aspects based on autonomous flight control. There have been many studies about the flight control for multirotor, but there is still room for enhancements in terms of performance and efficiency. This paper presents an autonomous flight control method for multirotor based on alternative input output linearization coupled with nested saturations. With alternative choice of the output of the multirotor flight control system, we can reduce computational cost regarding Lie algebra, and the linearized system can be stabilized with the introduction of nested saturations with real poles of our own design. Stabilization of internal dynamics is also based on the nested saturations and accompanies the determination of part of desired states. In particular, outer control loops involving state variables which originally are not included in the output of the flight control system is naturally rendered through this internal dynamics stabilization. We can also observe that desired tilting angles are determined by error dynamics from outer loops. Simulation results show that in any tracking situations multirotor stabilizes itself with small time constants, preceded by tuning process for control parameters with relatively low degree of complexity. Future study includes control of piecewise linear behavior of multirotor with actuator saturations, and the optimal determination of desired states while tracking multiple waypoints.

Keywords: automatic flight control, input output linearization, multirotor, nested saturations

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Authors: Garry Gorman, Nigel McKelvey, James Connolly

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This study will evaluate a growth mindset intervention with Junior Cycle Coding and Senior Cycle Computer Science students in Ireland, where gamification will be used to incentivise growth mindset behaviour. An artificial intelligence (AI) driven personalised learning system will be developed to present computer programming learning tasks in a manner that is best suited to the individuals’ own learning preferences while incentivising and rewarding growth mindset behaviour of persistence, mastery response to challenge, and challenge seeking. This research endeavours to measure mindset with before and after surveys (conducted nationally) and by recording growth mindset behaviour whilst playing a digital game. This study will harness the capabilities of AI and aims to determine how a personalised learning (PL) experience can impact the mindset of a broad range of students. The focus of this study will be to determine how personalising the learning experience influences female and disadvantaged students' sense of belonging in the computer science classroom when tasks are presented in a manner that is best suited to the individual. Whole Brain Learning will underpin this research and will be used as a framework to guide the research in identifying key areas such as thinking and learning styles, cognitive potential, motivators and fears, and emotional intelligence. This research will be conducted in multiple school types over one academic year. Digital games will be played multiple times over this period, and the data gathered will be used to inform the AI algorithm. The three data sets are described as follows: (i) Before and after survey data to determine the grit scores and mindsets of the participants, (ii) The Growth Mind-Set data from the game, which will measure multiple growth mindset behaviours, such as persistence, response to challenge and use of strategy, (iii) The AI data to guide PL. This study will highlight the effectiveness of an AI-driven personalised learning experience. The data will position AI within the Irish educational landscape, with a specific focus on the teaching of CS. These findings will benefit coding and computer science teachers by providing a clear pedagogy for the effective delivery of personalised learning strategies for computer science education. This pedagogy will help prevent students from developing a fixed mindset while helping pupils to exhibit persistence of effort, use of strategy, and a mastery response to challenges.

Keywords: computer science education, artificial intelligence, growth mindset, pedagogy

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Authors: Arash Sadeghi, Taimaz Larimian

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This study explores the intricate interplay between community-based social capital (CBSC) and neighbourhood dynamics in enhancing resilience of Iranian SMEs, particularly under the strain of international sanctions. Utilising fuzzy-set Qualitative Comparative Analysis (fsQCA), we examine how different dimensions of CBSC—structural, relational, and cognitive—interact with neighbourhood socio-economic and built-environment characteristics to influence SME resilience. Findings reveal four configurations that contribute to the presence of resistance and five configurations associated with the adaptation outcome. Each configuration demonstrates a distinct combination of social capital elements, which vary according to the specific socio-economic and built-environmental characteristics of the neighbourhoods. The first configuration highlights the importance of structural social capital in deprived areas for building resistance, while the second emphasises the role of relational social capital in low-density, minimally deprived areas. Overall, cognitive social capital seems to be less effective in driving economic resilience compared to structural and relational types. This research contributes to the literature by providing a nuanced understanding of the synergistic effects of CBSC dimensions and neighbourhood characteristics on SME resilience. By adopting a configurational approach, we move beyond traditional methodologies, offering a comprehensive view of the complex dynamics of CBSC and neighbourhood characteristics and their impact on SME resilience in varying neighbourhoods.

Keywords: community-based social capital, fuzzy-set qualitative comparative analysis (fsQCA), place-based resilience, resistance

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Authors: Teerada Apibunyopas, Nithinant Thammakoranonta

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Many organizations bring e-Learning to use as a tool in their training and human development department. It is getting more popular because it is easy to access to get knowledge all the time and also it provides a rich content, which can develop the employees skill efficiently. This study focused on the factors that affect using e-Learning efficiently, so it will make job satisfaction increased. The questionnaires were sent to employees in large commercial banks, which use e-Learning located in Bangkok, the results from multiple linear regression analysis showed that employee’s characteristics, characteristics of e-Learning, learning and growth have influence on job satisfaction.

Keywords: e-Learning, job satisfaction, learning and growth, Bangkok

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Authors: Akunna Agunwah, Kevin Gallimore, Kathryn Kinnmond

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Entrepreneurship and project management are widely associated and seen as a vehicle for economic growth, but are studied separately. A few authors have considered the interconnectivity existing between these two fields, but relatively little empirical data currently exist in the literature. The purpose of the present empirical study is to explore whether successful entrepreneurs utilise project management approaches in enhancing enterprise growth by understanding the working practices and experiences of the entrepreneurs’ using the Theory of Planned Behaviour (TPB) as a lens. In order to understand those experiences, ten successful entrepreneurs in various business sectors in the North West of England were interviewed through a face-to-face semi-structured interview method. The collected audio tape-recorded data was transcribed and analysed using the deductive thematic technique (qualitative approach). The themes were viewed through the lens of Theory of Planned Behaviour to identify the three intentional antecedents (attitude, subjective norms, and perceived behavioural control) and to understand how they relate to the project management approaches (Planning, execution, and monitoring). The findings are twofold, the first evidence of the three intentional antecedents, which make up Theory of Planned Behaviour was present. Secondly, the analysis of project management approaches themes (planning, execution, and monitoring) using the lens of the theory of planned behaviour shows evidence of the three intentional antecedents. There were more than one intentional antecedents found in a particular project management theme, which indicates that the entrepreneur does utilise these approaches without categorising them into definite themes. However, the entrepreneur utilised these intentional antecedents as processes to enhanced business growth. In conclusion, the work presented here showed a way of understanding the interconnectivity between entrepreneurship and project management towards enhancing enterprise growth by examining the working practices and experiences of the successful entrepreneurs in the North-West England.

Keywords: business growth, entrepreneurship, project management approaches, theory of planned behaviour

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Authors: Marco Ferretti, Marcello Risitano, Maria Cristina Pietronudo, Lina Ozturk

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A green port is the result of a sustainable long-term strategy adopted by an entire port infrastructure, therefore by the set of actors involved in port activities. The strategy aims to realise the development of sustainable port infrastructure focused on the reduction of negative environmental impacts without jeopardising economic growth. Green technology represents the core tool to implement sustainable solutions, however, they are not a magic bullet. Ports have always been integrated in the local territory affecting the environment in which they operate, therefore, the sustainable strategy should fit with the entire local systems. Therefore, adopting a sustainable strategy means to know how to involve and engage a wide stakeholders’ network (industries, production, markets, citizens, and public authority). The existing research on the topic has not well integrated this perspective with those of sustainability. Research on green ports have mixed the sustainability aspects with those on the maritime industry, neglecting dynamics that lead to the development of the green port phenomenon. We propose an analysis of green ports adopting the lens of ecosystem studies in the field of management. The ecosystem approach provides a way to model relations that enable green solutions and green practices in a port ecosystem. However, due to the local dimension of a port and the port trend on innovation, i.e., sustainable innovation, we draw to a specific concept of ecosystem, those on local innovation systems. More precisely, we explore if a green port is a local innovation system engaged in developing sustainable innovation with a large impact on the territory or merely an innovation adopter. To address this issue, we adopt a comparative case study selecting two innovative ports in Europe: Rotterdam and Genova. The case study is a research method focused on understanding the dynamics in a specific situation and can be used to provide a description of real circumstances. Preliminary results show two different approaches in supporting sustainable innovation: one represented by Rotterdam, a pioneer in competitiveness and sustainability, and the second one represented by Genoa, an example of technology adopter. The paper intends to provide a better understanding of how sustainable innovations are developed and in which manner a network of port and local stakeholder support this process. Furthermore, it proposes a taxonomy of green ports as developers and adopters of sustainable innovation, suggesting also best practices to model relationships that enable the port ecosystem in applying a sustainable strategy.

Keywords: green port, innovation, sustainability, local innovation systems

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Authors: S. Da Costa, D. Páez, F. Sánchez

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We examine the causal role of positive affect on creativity, the association of creativity or innovation in the ideation phase with functional emotional regulation, successful adjustment to stress and dispositional emotional creativity, as well as the predictive role of creativity for positive emotions and social adjustment. The study examines the effects of modification of positive affect on creativity. Participants write three poems, narrate an infatuation episode, answer a scale of personal growth after this episode and perform a creativity task, answer a flow scale after creativity task and fill a dispositional emotional creativity scale. High and low positive effect was induced by asking subjects to write three poems about high and low positive connotation stimuli. In a neutral condition, tasks were performed without previous affect induction. Subjects on the condition of high positive affect report more positive and less negative emotions, more personal growth (effect size r = .24) and their last poem was rated as more original by judges (effect size r = .33). Mediational analysis showed that positive emotions explain the influence of the manipulation on personal growth - positive affect correlates r = .33 to personal growth. The emotional creativity scale correlated to creativity scores of the creative task (r = .14), to the creativity of the narration of the infatuation episode (r = .21). Emotional creativity was also associated, during performing the creativity task, with flow (r = .27) and with affect balance (r = .26). The mediational analysis showed that emotional creativity predicts flow through positive affect. Results suggest that innovation in the phase of ideation is associated with a positive affect balance and satisfactory performance, as well as dispositional emotional creativity is adaptive.

Keywords: affectivity, creativity, induction, innovation, psychological factors

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Authors: Takele Bekele Bayu

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Though Ethiopia is an ancient country with ethnocultural and linguistic diversity, modern Ethiopia came into being in the second half of the 19th century under the military expansion of King Menelik II. Since then, the subsequent political system in the country failed to recognize and accommodate the country’s ethnolinguistic diversity. However, in 1991 the new government led by the Ethiopian People's Revolutionary Democratic Front (EPRDF) adopted federal-state structuring whereby constitutionally recognized and institutionally accommodated the country’s diversity. This investigation aimed to analyze drivers of ethnic conflict and its dynamism along the Eastern shared border of the Somali and Oromia regional administrations within the federal framework. The paper employed a comparative research design, adopted mixed research methods, and used survey questionnaires and focus group discussions (FGDs) for data collection. The study found that the Somali-Oromo conflict is complex and the dynamics and the sources of conflict in the study areas are similar.

Keywords: Ethiopia, Oromo, Somali, ethnic conflict, federalism

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Authors: Liliia N. Butymova, Vladimir Ya Modorskii

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To ensure the gas transmittal GCU's efficient operation, leakages through the labyrinth packings (LP) should be minimized. Leakages can be minimized by decreasing the LP gap, which in turn depends on thermal processes and possible rotor vibrations and is designed to ensure absence of mechanical contact. Vibration mitigation allows to minimize the LP gap. It is advantageous to research influence of processes in the dynamic gas-structure system on LP vibrations. This paper considers influence of rotor vibrations on LP gas dynamics and influence of the latter on the rotor structure within the FSI unidirectional dynamical coupled problem. Dependences of nonstationary parameters of gas-dynamic process in LP on rotor vibrations under various gas speeds and pressures, shaft rotation speeds and vibration amplitudes, and working medium features were studied. The programmed multi-processor ANSYS CFX was chosen as a numerical computation tool. The problem was solved using PNRPU high-capacity computer complex. Deformed shaft vibrations are replaced with an unyielding profile that moves in the fixed annulus "up-and-down" according to set harmonic rule. This solves a nonstationary gas-dynamic problem and determines time dependence of total gas-dynamic force value influencing the shaft. Pressure increase from 0.1 to 10 MPa causes growth of gas-dynamic force oscillation amplitude and frequency. The phase shift angle between gas-dynamic force oscillations and those of shaft displacement decreases from 3π/4 to π/2. Damping constant has maximum value under 1 MPa pressure in the gap. Increase of shaft oscillation frequency from 50 to 150 Hz under P=10 MPa causes growth of gas-dynamic force oscillation amplitude. Damping constant has maximum value at 50 Hz equaling 1.012. Increase of shaft vibration amplitude from 20 to 80 µm under P=10 MPa causes the rise of gas-dynamic force amplitude up to 20 times. Damping constant increases from 0.092 to 0.251. Calculations for various working substances (methane, perfect gas, air at 25 ˚С) prove the minimum gas-dynamic force persistent oscillating amplitude under P=0.1 MPa being observed in methane, and maximum in the air. Frequency remains almost unchanged and the phase shift in the air changes from 3π/4 to π/2. Calculations for various working substances (methane, perfect gas, air at 25 ˚С) prove the maximum gas-dynamic force oscillating amplitude under P=10 MPa being observed in methane, and minimum in the air. Air demonstrates surging. Increase of leakage speed from 0 to 20 m/s through LP under P=0.1 MPa causes the gas-dynamic force oscillating amplitude to decrease by 3 orders and oscillation frequency and the phase shift to increase 2 times and stabilize. Increase of leakage speed from 0 to 20 m/s in LP under P=1 MPa causes gas-dynamic force oscillating amplitude to decrease by almost 4 orders. The phase shift angle increases from π/72 to π/2. Oscillations become persistent. Flow rate proved to influence greatly on pressure oscillations amplitude and a phase shift angle. Work medium influence depends on operation conditions. At pressure growth, vibrations are mostly affected in methane (of working substances list considered), and at pressure decrease, in the air at 25 ˚С.

Keywords: aeroelasticity, labyrinth packings, oscillation phase shift, vibration

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Authors: Amritanshu Shriwastav, Purnendu Bose

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Algal photo bioreactors were operated at incident light intensities of 0.24, 2.52 and 5.96 W L-1 to determine the impact of light on algal growth. Low specific Chlorophyll-a content of algae was a strong indicator of light induced stress on algal cells. It was concluded that long term operation of photo bioreactors in the continuous illumination mode was infeasible under the range of incident light intensities examined and provision of a dark period after each light period was necessary for algal cells to recover from light-induced stress. Long term operation of photo bioreactors in the intermittent illumination mode was however possible at light intensities of 0.24 and 2.52 W L-1. Further, the incident light intensity in the photo bioreactors was found to decline exponentially with increase in algal concentration in the reactor due to algal ‘self-shading’. This may be an important determinant for photo bioreactor performance at higher algal concentrations.

Keywords: Algae, algal growth, photo bioreactor, photo-inhibition, ‘self-shading’

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Authors: Ming-Tzu Tsai, Jui-Ting Hsu, Chia-Chieh Lin, Feng-Tsai Chiang, Cheng-Chin Huang

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Far infrared (FIR), an invisible and short electromagnetic waves ranges from 6-14 μm also defines as the “growth ray.” Although the mechanism of FIR is still unknown, most data have suggested that FIR could accelerate the skin microcirculation by elevating the blood flow and nitric-oxide (NO) synthesis. In this present work, the effect of FIR irradiation and endothelial cell growth supplement (ECGS) on human umbilical vascular endothelial cells (HUVECs) was evaluated. To understand whether the cell viability and NO production of HUVECs affected by NO, cells with/without ECGS were treated in the presence or absence of L-NAME, an eNOS inhibitor. For FIR exposure, FIR-emitted ceramic powders consisted of a variety of well-mixed metal oxides were developed. The results showed that L-NAME did had a strong effect on the inhibition of NO production, especially in the ECGS-treated group. However, the cell viability of each group was rarely affected in the presence of L-NAME. Cells with the incubation of ECGS showed much higher cell viability compared to the control. Moreover, NO production of HUVECs exposed to FIR irradiation was significantly inhibited in the presence of L-NAME. It suggested that NO could play a role modulating the downstream signals of HUVECs during FIR exposure.

Keywords: far-infrared irradiation (FIR), nitric oxide (NO), endothelial nitric oxide synthase (eNOS), endothelial cell growth supplement (ECGS)

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Authors: Nora Laref, Bettache Guessas

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Preservation of foods mainly depends on delaying or inhibiting the growth of spoilage microorganisms, and antifungal activity of lactic acid bacteria is one of the technological properties researched. The antifungal activity was screened with overlay method of six strains of lactic acid bacteria (Lactobacillus plantarum LB54, LB52, LB51, LB20, LB24 Lactobacillus farciminis LB53) isolated from silage, camel milk and carrot against Aspergillus sp. Lactobacillus plantarum and farciminis inhibit spore germination and mycelia growth of Aspergillus sp., the production of antifungal compounds by these strains was detectable after 4h of incubation at 30°C and show total inhibition after 24h in liquid media, but in solid media showed a good inhibition after 96h of incubation, these compounds cause malformations in the thalle, conidiophore and conidia. These strains could be used as agents of biopreservation since have the ability to retard Aspergillus sp., growth in apricot juice with and without sugar conserved in refrigerator but not in bread.

Keywords: lactobacillus, antifungal substances, aspergillus, biopreservation

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Authors: A. Maria G. Melero, A. M. Senna, J. A. Domingues, M. A. Hausen, E. Aparecida R. Duek, V. R. Botaro

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A hydrogel from cellulose acetate cross linked with ethylenediaminetetraacetic dianhydride (HAC-EDTA) was synthesized by our research group, and submitted to characterization and biological tests. Cytocompatibility analysis was performed by confocal microscopy using human adipocyte derived stem cells (ASCs). The FTIR analysis showed characteristic bands of cellulose acetate and hydroxyl groups and the tensile tests evidence that HAC-EDTA present a Young’s modulus of 643.7 MPa. The confocal analysis revealed that there was cell growth at the surface of HAC-EDTA. After one day of culture the cells presented spherical morphology, which may be caused by stress of the sequestration of Ca²⁺ and Mg²⁺ ions at the cell medium by HAC-EDTA, as demonstrated by ICP-MS. However, after seven days and 14 days of culture, the cells present fibroblastoid morphology, phenotype expected by this cellular type. The results give efforts to indicate this new material as a potential biomaterial for tissue engineering, in the future in vivo approach.

Keywords: cellulose acetate, hydrogel, biomaterial, cellular growth

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Authors: Etsuo Morishita

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In this paper, we show shallow water in a tin box as an analogous simulation tool for high-speed aerodynamics education and research. It is customary that we use a water tank to create shallow water flow. While a flow in a water tank is not necessarily uniform and is sometimes wavy, we can visualize a clear supercritical flow even when we move a body manually in stationary water in a simple shallow tin box. We can visualize a blunt shock wave around a moving circular cylinder together with a shock pattern around a diamond airfoil. Another interesting analogous experiment is a hydrodynamic shock tube with water and tea. We observe the contact surface clearly due to color difference of the two liquids those are invisible in the real gas dynamics experiment. We first revisit the similarities between high-speed aerodynamics and shallow water hydraulics. Several educational and research experiments are then introduced for engineering students. Shallow water experiments in a tin box simulate properly the high-speed flows.

Keywords: aerodynamics compressible flow, gas dynamics, hydraulics, shock wave

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Authors: Vasileios Floros

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This article delves into the intricate interplay between leadership styles and teacher satisfaction within the Greek educational framework, underscoring the pivotal role of school leadership in shaping educational success and fostering a conducive school culture. Through a comprehensive analysis, the study explores various leadership theories, the psychological contract between teachers and leaders, and the impact of leadership on teacher job satisfaction and group dynamics within educational institutions. It highlights how leadership efficacy can significantly influence the organizational climate, teacher motivation, and, ultimately, educational outcomes. The findings suggest that effective leadership, characterized by a deep understanding of teacher psychology, thoughtful engagement with the school culture, and strategic application of leadership styles, can lead to heightened teacher satisfaction and enhanced educational performance. This research offers valuable insights for educational policymakers, school leaders, and the broader academic community interested in optimizing leadership practices to foster an enriching educational environment in Greece.

Keywords: educational leadership, teacher satisfaction, school culture, leadership styles, Greek education

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Authors: Muhammad Naveed, Sohail Yousaf, Zahir Ahmad Zahir, Birgit Mitter, Angela Sessitsch

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Most bacterial endophytes originate from the soil and enter plants via the roots followed by further spread through the inner tissues. The mechanisms allowing bacteria to colonize plants endophytically are still poorly understood for most bacterial and plant species. Specific bacterial functions are required for plant colonization, but also the plant itself is a determining factor as bacterial ability to establish endophytic populations is very often dependent on the plant genotype (cultivar) and inoculums density. The effect of inoculum density (107, 108, 109 CFU mL-1) of Burkholderia phytofirmans strain PsJN was evaluated on growth and endophytic colonization of different maize and potato cultivars under axenic and natural soil conditions. PsJN inoculation significantly increased maize seedling growth and tuber yield of potato at all inoculum density compared to uninoculated control. Under axenic condition, PsJN inoculation (108 CFU mL-1) significantly improved the germination, root/shoot length and biomass up to 62, 115, 98 and 135% of maize seedling compared to uninoculated control. In case of potato, PsJN inoculation (109 CFU mL-1) showed maximum response and significantly increased root/shoot biomass and tuber yield under natural soil condition. We confirmed that PsJN is able to colonize the rhizosphere, roots and shoots of maize and potato cultivars. The endophytic colonization increased linearly with increasing inoculum density (within a range of 8 x 104 – 3 x 107 CFU mL-1) and were highest for maize (Morignon) and potato (Romina) as compared to other cultivars. Efficient colonization of cv. Morignon and Romina by strain PsJN indicates the specific cultivar colonizing capacity of the bacteria. The findings of the study indicate the non-significant relationship between colonization and plant growth promotion in maize under axenic conditions. However, the inoculum level (109 CFU mL-1) that promoted colonization of rhizosphere and plant interior (endophytic) also best promoted growth and tuber yield of potato under natural soil conditions.

Keywords: crop genotype, inoculum density, Burkholderia phytofirmans PsJN, colonization, growth, potato

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Authors: L. Steponavičiūtė, L. Steponavičienė

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Despite the rapid nanotechnology progress and recognition, its potential impact in ecosystems and health of humans is still not fully known. In this paper, the study of ecotoxicological dangers of nanomaterials is presented. By chemical reduction method, silver (AgNPs) and gold (AuNPs) nanoparticles were synthesized, characterized and used in experiments to examine their impact on microorganisms (Escherichia coli, Staphylococcus aureus and Candida albicans) and terrestrial flora (Phaseolus vulgaris and Lepidium sativum). The results collected during experiments with terrestrial flora show tendentious growth stimulations caused by gold nanoparticles. In contrast to these results, silver nanoparticle solutions inhibited growth of beans and garden cress, compared to control samples. The results obtained from experiments with microorganisms show similarities with ones collected from experiments with terrestrial plants. Samples treated with AuNPs of size 13 nm showed stimulation in the growth of the colonies compared with 3,5 nm size nanoparticles.

Keywords: nanomaterials, ecotoxicology, nanoparticles, ecosystems

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Authors: Ryeong-Hyeon Kim, Ah-Reum Lee, Seong-Soo Roh, Gyo-Nam Kim

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Appropriate regulation of melanogenesis is important for the management of skin pigmentation-related disease. Although several beneficial effects of fisetin (3,7,3’,4’-tetrahydroxyflavone) have been reported, the precise role and molecular mechanisms of fisetin in skin health both remain unclear. Here, we induced melanogenesis of HRM2 mice (n=7/group) by UVB irradiation for 20 days. UVB-induced HRM2 mice showed that the significantly increased melanin accumulation, however, fisetin treatment (25mg and 50mg/kg of body weight) dose-dependently and significantly inhibits UVB-induced melanogenesis. In line with this, fisetin treatment effectively down-regulated m RNA and expression levels of tyrosinase, TRP2, and MITF. In addition, our inhibitor assay revealed the down-regulated melanogenic marker genes by fisetin treatment were mediated with connective tissue growth factor (CCN2)/TGF-β signaling pathway. Useful information is provided for development of functional foods using fisetin for skin health.

Keywords: connective tissue growth factor, fisetin, melanogenesis, skin, TGF-beta

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Authors: Ahmad Haidar

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Modern economic systems are characterized by growing complexity, and addressing their challenges requires innovative approaches. This study examines the implications of artificial intelligence (AI) on unemployment in Europe from a macroeconomic perspective, employing data modeling techniques to understand the relationship between AI integration and labor market dynamics. To understand the AI-unemployment nexus comprehensively, this research considers factors such as sector-specific AI adoption, skill requirements, workforce demographics, and geographical disparities. The study utilizes a panel data model, incorporating data from European countries over the last two decades, to explore the potential short-term and long-term effects of AI implementation on unemployment rates. In addition to investigating the direct impact of AI on unemployment, the study also delves into the potential indirect effects and spillover consequences. It considers how AI-driven productivity improvements and cost reductions might influence economic growth and, in turn, labor market outcomes. Furthermore, it assesses the potential for AI-induced changes in industrial structures to affect job displacement and creation. The research also highlights the importance of policy responses in mitigating potential negative consequences of AI adoption on unemployment. It emphasizes the need for targeted interventions such as skill development programs, labor market regulations, and social safety nets to enable a smooth transition for workers affected by AI-related job displacement. Additionally, the study explores the potential role of AI in informing and transforming policy-making to ensure more effective and agile responses to labor market challenges. In conclusion, this study provides a comprehensive analysis of the macroeconomic implications of AI on unemployment in Europe, highlighting the importance of understanding the nuanced relationships between AI adoption, economic growth, and labor market outcomes. By shedding light on these relationships, the study contributes valuable insights for policymakers, educators, and researchers, enabling them to make informed decisions in navigating the complex landscape of AI-driven economic transformation.

Keywords: artificial intelligence, unemployment, macroeconomic analysis, european labor market

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Authors: M. Youngsabanant-Areekijseree, C. Thepsithar, K. Sribuddhachart, J. Tananantayot

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Porcine oviductal fluid (pOF) from oviduct, an unused organ from the slaughterhouse, was effectively used for biotechnology studies. The fluid components consisted of micro- and macro-nutrients, amino acids, carbon source and proteins that played important roles in animal cell and embryo development. This was our knowledge on investigating pOF as growth promoting substance in culture medium of an orchid, Dendrobium mirbelianum. Two-leaf shoots were cultured in liquid Vacin and Went (VW) medium as a standard medium supplemented with 2 g/L peptone (Pe) or 100 g/ L boiled-potato water (Po) alone or in combinations, and added with 0, 1, 3 or 5 ml/L pOF. All explants were cultured in a stationary condition for 8 weeks. It was found that medium added with 100 g/L Po and 1 ml/L pOF provided the best results (1.02 g fresh weight, 4.2 shoots, 0.53 cm shoot height, 4.4 protocorms, 11.0 leaves and 5.7 roots with 100% survival) when compared to other medium, but not statistically significant difference from medium added with 100 g/L Po (0.86 g fresh weight, 4.3 shoots, 0.51 cm shoot height, 4.6 protocorms, 12.4 leaves and 6.6 roots with 100% survival). However, VW medium supplemented with 1 or 3 ml/L pOF alone showed the higher percentage of survival (100%) than VW medium (86.67%). It was shown the potential role of pOF as an organic supplement for promoting growth of plants. Acknowledgements—The project was funded by a grant from Silpakorn University Research & Development Institute (SURDI) and Faculty of Science, Silpakorn University, Thailand.

Keywords: Dendrobium mirbelianum, pig, oviductal fluid, in vitro growth

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Authors: Ragini Verma, J. Ponmozhi

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The oral cavity is home to a wide variety of microorganisms that lead to various diseases and even oral cancer. Despite advancements in the diagnosis and detection at the initial phase, the situation hasn’t improved much. Saliva-on-a-chip is an innovative point-of-care platform for early diagnosis of oral cancer and other oral diseases in live and dead cells using a microfluidic device with a current perspective. Some of the major challenges, like real-time imaging of the oral cancer microbes, high throughput values, obtaining a high spatiotemporal resolution, etc. were faced by the scientific community. Integrated microfluidics and microscopy provide powerful approaches to studying the dynamics of oral pathology, microbe interaction, and the oral microenvironment. Here we have developed a saliva-on-chip (salivary microbes) device to monitor the effect on oral cancer. Adhesion of cancer-causing F. nucleatum; subsp. Nucleatum and Prevotella intermedia in the device was observed. We also observed a significant reduction in the oral cancer growth rate when mortality and morbidity were induced. These results show that this approach has the potential to transform the oral cancer and early diagnosis study.

Keywords: microfluidic device, oral cancer microbes, early diagnosis, saliva-on-chip

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Authors: Prince Suka Neekia Momta, Rita Iheoma Achonyeulo

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Ant Tracking seismic attribute applied over 4-seconds seismic volume revealed structural features triggered by clay diapirism, growth fault development, rapid deltaic sedimentation and intense drilling. The attribute was extracted on vertical seismic sections and time slices. Mega tectonic structures such as growth faults and clay diapirs are visible on vertical sections with obscured minor lineaments or fractures. Fractures are distinctively visible on time slices yielding recognizable patterns corroborating established geologic models. This model seismic attribute enabled the understanding of fluid flow characteristics and production responses. Three structural patterns recognized in the field include: major growth faults, minor faults or lineaments and network of fractures. Three growth faults mapped on seismic section form major deformation bands delimiting the area into three blocks or depocenters. The growth faults trend E-W, dip down-to-south in the basin direction, and cut across the study area. The faults initiating from about 2000ms extended up to 500ms, and tend to progress parallel and opposite to the growth direction of an upsurging diapiric structure. The diapiric structures form the major deformational bands originating from great depths (below 2000ms) and rising to about 1200ms where series of sedimentary layers onlapped and pinchout stratigraphically against the diapir. Several other secondary faults or lineaments that form parallel streaks to one another also accompanied the growth faults. The fracture networks have no particular trend but form a network surrounding the well area. Faults identified in the study area have potentials for structural hydrocarbon traps whereas the presence of fractures created a fractured-reservoir condition that enhanced rapid fluid flow especially water. High aquifer flow potential aided by possible fracture permeability resulted in rapid decline in oil rate. Through the application of Ant Tracking attribute, it is possible to obtain detailed interpretation of structures that can have direct influence on oil and gas production.

Keywords: seismic, attributes, production, structural

Procedia PDF Downloads 70

Authors: T. Büyüksırıt, H. Kuleaşan

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Natural antimicrobials are used to preserve foods that can be found in plants, animals, and microorganisms. Antimicrobial substances are natural or artificial agents that produced by microorganisms or obtained semi/total chemical synthesis are used at low concentrations to inhibit the growth of other microorganisms. Food borne pathogens and spoilage microorganisms are inactivated by the use of antagonistic microorganisms and their metabolites. Yeasts can produce toxic proteins or glycoproteins (toxins) that cause inhibition of sensitive bacteria and yeast species. Antimicrobial substance producing phenotypes belonging different yeast genus were isolated from different sources. Toxins secreted by many yeast strains inhibiting the growth of other yeast strains. These strains show antimicrobial activity, inhibiting the growth of mold and bacteria. The effect of antimicrobial agents produced by yeasts can be extremely fast, and therefore may be used in various treatment procedures. Rapid inhibition of microorganisms is possibly caused by microbial cell membrane lipopolysaccharide binding and in activation (neutralization) effect. Antimicrobial agents inhibit the target cells via different mechanisms of action.

Keywords: antimicrobial agents, yeast, toxic protein, glycoprotein

Procedia PDF Downloads 362

Authors: Hanee Ryu

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The former president Lee Myung-bak's administration of Korea presented “green growth” as a catchphrase from 2008. He declared “low-carbon, green growth” the nation's vision for the next decade according to United Nation Framework on Climate Change. The government designed omnidirectional policy for low-carbon and green growth with concentrating all effort of departments. The structural change was expected because this slogan is the identity of the government, which is strongly driven with the whole department. After his administration ends, the purpose of this paper is to quantify the policy effect and to compare with the value of the other OECD countries. The major target values under direct policy objectives were suggested, but it could not capture the entire landscape on which the policy makes changes. This paper figures out the policy impacts through comparing the value of ex-ante between the one of ex-post. Furthermore, each index level of Korea’s low-carbon and green growth comparing with the value of the other OECD countries. To measure the policy effect, indicators international organizations have developed are considered. Environmental Sustainable Index (ESI) and Environmental Performance Index (EPI) have been developed by Yale University’s Center for Environmental Law and Policy and Columbia University’s Center for International Earth Science Information Network in collaboration with the World Economic Forum and Joint Research Center of European Commission. It has been widely used to assess the level of natural resource endowments, pollution level, environmental management efforts and society’s capacity to improve its environmental performance over time. Recently OCED publish the Green Growth Indicator for monitoring progress towards green growth based on internationally comparable data. They build up the conceptual framework and select indicators according to well specified criteria: economic activities, natural asset base, environmental dimension of quality of life and economic opportunities and policy response. It considers the socio-economic context and reflects the characteristic of growth. Some selected indicators are used for measuring the level of changes the green growth policies have induced in this paper. As results, the CO2 productivity and energy productivity show trends of declination. It means that policy intended industry structure shift for achieving carbon emission target affects weakly in the short-term. Increasing green technologies patents might result from the investment of previous period. The increasing of official development aids which can be immediately embarked by political decision with no time lag present only in 2008-2009. It means international collaboration and investment to developing countries via ODA has not succeeded since the initial stage of his administration. The green growth framework makes the public expect structural change, but it shows sporadic effect. It needs organization to manage it in terms of the long-range perspectives. Energy, climate change and green growth are not the issue to be handled in the one period of the administration. The policy mechanism to transfer cost problem to value creation should be developed consistently.

Keywords: comparing ex-ante between ex-post indicator, green growth indicator, implication for green growth policy, measuring policy effect

Procedia PDF Downloads 448

Authors: Alexander Blokhin, Ekaterina Kruglova, Boris Semisalov

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Mathematical model based on the mesoscopic theory of polymer dynamics is developed for numerical simulation of the flows of polymeric liquid between two coaxial cylinders. This model is a system of nonlinear partial differential equations written in the cylindrical coordinate system and coupled with the heat conduction equation including a specific dissipation term. The stationary flows similar to classical Poiseuille ones are considered, and the resolving equations for the velocity of flow and for the temperature are obtained. For solving them, a fast pseudospectral method is designed based on Chebyshev approximations, that enables one to simulate the flows through the channels with extremely small relative values of the radius of inner cylinder. The numerical analysis of the dependance of flow on this radius and on the values of dissipation constant is done.

Keywords: dynamics of polymeric liquid, heat dissipation, singularly perturbed problem, pseudospectral method, Chebyshev polynomials, stabilization technique

Procedia PDF Downloads 290

Authors: Raghavi Janaswamy, Srinivas Janaswamy

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Emotional Intelligence (EI) measures the degree to which individuals can identify, understand and manage emotions. Indeed, it highlights the intricate relationship between thoughts, feelings, and behavior of an individual. In today's world, EI competencies appear to be more valuable compared to cognitive and/or technical expertise. Higher EI endows realistic confidence to perceive challenges with positive thinking and, in turn, offers a steady growth as well as the speed of work and discerning ability. It certainly plays a vital role for aspirants to ascend the organizational ladder and distinguishes outstanding leaders from the rest. Emotional maturity further reflects on the behavioral pattern toward dealing with self and the immediate environment. Indeed, it aids in cementing inter-personal relations at a workplace with a thorough understanding and certainly paves the way for leaders to their prosperity as well as organizational growth. Herein, EI contributions to an individual, team, and organizational success are discussed with an emphasis on the required tools to acquire higher EI traits. The strategies for promoting self-awareness, empathy, and social skills and changing trends of the new programs for the EI improvement are also highlighted.

Keywords: emotional intelligence, leadership, organizational growth, self-awareness skills

Procedia PDF Downloads 82