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Phytotherapeutic analysis of chloroform-based fractions of Alstonia scholaris and Wrightia tinctoria extracts reveals potent anti-psoriatic activity: an in vitro and in vivo study
Get PDFBackground/Objectives: Psoriasis, a prevalent dermatological disorder, poses therapeutic challenges due to limited effective treatments or adverse side-effects. Traditional medicinal plants like Alstonia scholaris and Wrightia tinctoria, historically used in Ayurvedic and Siddha practices, show potential in treating inflammatory skin diseases. This study aims to explore their in vitro and in vivo anti-psoriatic properties to develop safer and more effective therapies. Methods: Chloroform:methanol fractions from ethanol extracts of Alstonia scholaris and Wrightia tinctoria were evaluated for anti-psoriatic activity. In vitro assays using HaCaT cells assessed cell viability, apoptosis, and inflammatory markers. In vivo studies utilized an IMQ-induced psoriasis mouse model, evaluating skin lesions, histopathology, and cytokine profiles. Results: Chloroform fractions significantly reduced HaCaT cell viability and induced apoptosis. They also dose-dependently downregulated IL-8 and RANTES levels. In vivo, these fractions reduced skin inflammation, edema, and psoriasis scores. Histopathological analysis showed decreased epidermal thickness and dermal inflammation. Key psoriasis biomarkers IL-17 and IL-23 were significantly reduced. Conclusions: Chloroform:methanol fractions from Alstonia scholaris and Wrightia tinctoria demonstrated potent anti-psoriatic effects in vitro and in vivo. These findings support their potential as novel phytotherapeutic agents for managing psoriasis, offering promise for further development and clinical application.Pharmaceutical
Analysis of factors driving foreign direct investment in the liquefied natural gas sector: case study Nigeria
No full textHuo, Da - Associate SupervisorThe empirical data revealed facts about factors driving foreign direct investment
in the Nigerian LNG sector. This research uses the primary data gathered to
contribute uniquely to empirical findings and knowledge. Some factors are
deemed adequate when attracting foreign direct investment. The sufficient
factors identified are political stability having a considerable impact on investor
decisions, and long-term investment commitments in the LNG sector. The second
significant factor identified is government efficiency, and the last factor is
corruption with different components classified into two broad categories:
attractors and deterrents. In this context, sufficiency is defined as the condition
where FDI is likely to occur when a sufficient amount of the three factors listed
are in place. Previous research has failed to understand and explain all three
factors adequately. This is a new insight and contribution to knowledge. This
study explains how factors driving foreign direct investment in Nigeria's liquefied
natural gas sector have an impact. The research utilises the successful Bonny
NLNG projects as an example to investigate the reasons behind the failure of the
Olokola and Brass LNG projects, which were unable to reach a final investment
decision. Distinct empirical analysis and research design show key factors driving
foreign direct investment in the Nigerian LNG sector. Foreign direct investment is
a type of cross-border investment that occurs when an investor from one country
develops a long-term stake in and a considerable degree of control over an
enterprise located in another country. Additionally, in green-field investment,
foreign direct investment is in the form of a parent company establishing a
subsidiary in another country and commencing operations from the ground up.
The goal of foreign direct investment is the priority of gaining benefits from the
investment, maximising return on investment, and seeking to control assets. It
offers capital funding in exchange for an equity stake. LNG projects are capital-
intensive, it requires sizable up-front financing. LNG project financing can be
difficult due to their long-term nature, high costs, and associated risks. Securing
funds from foreign lenders, equity investors, and project sponsors can be
herculean, only the major exploration and production companies can achieve it.
Thus, the research will focus on factors driving FDI in the LNG sector. Key
stakeholders, policymakers, and investors will be interviewed. This thesis
compiles feedback from stakeholders to identify the key factors driving foreign
direct investment in Nigerian liquefied natural gas. The study presents evidence
on the factors driving the inflow of foreign direct investment into the Nigerian LNG
sector to policymakers, lawmakers, government executives, investors,
community leaders, and financial institutions to test the effectiveness and
efficiency of the research.
The research design incorporates a mixed-method approach. Data collected
through a questionnaire-based survey, semi-structured interviews, and focus
group discussions, provide solid insight into the factors driving foreign direct
investment in the Nigerian LNG sector. The questionnaire-based survey was
used to gather data from 118 respondents. Data was gathered from 12 top gas
stakeholders through semi-structured interviews, and an additional 4 executive
participants participated in the focus group discussion. The study employs
purposive sampling to identify the participants and interviewees. The
fundamental value of the research comes from the real-world data it collects and
the conclusions by looking at factors driving FDI in the LNG sector. Stakeholder
theories were chosen as the theoretical framework for the research, emphasising
the study's focus and applying the researcher's terminology to address the
research questions. The literature review guided this decision. Nigeria's
abundance of natural resources, particularly its substantial natural gas reserves,
attracts foreign investors. The Nigerian gas sector presents opportunities for
economic development, energy diversification, and environmental sustainability
in the future. Nigeria has about nine hundred times more gas assets than the
country's oil deposits, and its reputation as an oil producer overshadowed the gas
sector's potential, even though the country's gas reserves are greater than oil.
Gas asset is a necessary factor, but it is not sufficient enough to attract foreign
direct investment.PhD in Energy and Powe
Agent-based modelling of crop management
Get PDFWaine, Toby W. - Associate Supervisor
Metcalfe, Helen - Associate Supervisor
Alonso-Chavez, Vasthi - Associate SupervisorThis study aims to explore the benefits of integrating Agent-Based Models
(ABMs) of farmer behaviour with biophysical models to describe and understand
the complex agroecological systems that influence decision-making in arid and
semi-arid regions. Through a mixed-methods approach combining surveys,
interviews, and ABM, the research provides insights into the complex dynamics
shaping farmer behaviour and evaluates the potential impacts of various
management strategies on agricultural sustainability. Initial online surveys across
diverse agro-climatic zones in Morocco revealed that farmer decisions are
influenced by environmental pressures, crop characteristics, and water
availability. Follow-up in-depth interviews in the Al Haouz Basin highlighted
institutional barriers like land tenure insecurity and bureaucratic processes as key
constraints to adopting sustainable practices. The study integrates empirical data
with Structural Equation Modelling and the Theory of Planned Behaviour to
parameterize an ABM. This coupled behavioural-biophysical simulation captures
feedback loops between environmental conditions and human decisions. Model
simulations revealed potential unintended consequences of policies aimed at
increasing productivity, such as increased soil salinization and land abandonment
resulting from expanded groundwater access. Key contributions include
advancing the understanding of temporal adaptation dynamics in agricultural
systems under climate change and developing a novel methodological framework
integrating qualitative and quantitative approaches for studying complex socio-
ecological systems. By bridging social and natural sciences, this research
establishes a comprehensive framework for addressing agricultural sustainability
challenges in water-scarce regions.PhD in Environment and Agrifoo
A study of the motion response of floating solar PV and cross-flow savonius turbine in moored conditions
Get PDFThe transition towards Net Zero Emissions (NZEs) is being accelerated by hybrid renewable technologies such as Floating Photovoltaic (FPV) systems and marine current turbines, which combine solar panels and cross-flow marine turbines mounted on floating structures for near-shore applications. Despite their innovative potential, these renewable technologies face significant challenges in stability and durability due to the effects of wind, waves, and ocean currents. Therefore, a flexible mooring system is essential to address these challenges. This research examines the influence of variations in the number of mooring lines and wave direction on the hydrodynamic response of FPV systems. Utilizing a catenary mooring system consisting of anchors, mooring lines, floats, and connectors, the study evaluates various configurations to determine the optimal solution for enhanced motion stability. Computational Fluid Dynamics (CFD) simulations are employed to analyze the dynamic response of FPV systems under different environmental conditions, represented on a sea-state scale, with a focus on pure oscillatory motions: heave, roll, and pitch. The findings aim to provide valuable insights for the design and operation of more stable and efficient FPV systems in marine environments, thereby supporting the advancement of sustainable renewable energy.The research scheme is financed by Internal fund from Institut Teknologi Sepuluh Nopember (ITS) . The funding is disbursed through the PRIME ENGINEERING SEED FUND for the 2024/2025, Batch 2, with contract number 2502/PKS/ITS/2024.5th Sustainability and Resilience of Coastal Management (SRCM 2024)BIO Web of Conference
The known unknowns of petrogenic organic carbon in soils
Get PDFIntensifying effects of global climate change have spurred efforts to enhance carbon sequestration and the long‐term storage of soil organic carbon (OC). Current soil carbon models predominantly assume that inputs of OC are biospheric, that is, primarily derived from plant decomposition. However, these overlook the contribution of OC from soil parent material, including petrogenic organic carbon (OCpetro) from OC‐bearing (meta‐)sedimentary bedrock. To our knowledge, no soil carbon model accounts for the inputs of OCpetro to soils, resulting in significant gaps in our understanding about the roles OCpetro plays in soils. Here, we call for cross‐disciplinary research to investigate the transport and stability of OCpetro across the bedrock–soil continuum. We pose four key questions as motivation for this effort. Ignoring the inputs of OCpetro to soils has significant implications, including overestimating biospheric carbon stocks and turnover times. Furthermore, we lack information on the role that OCpetro may play in priming microbial communities, as well as the impacts of land management on OCpetro stocks.The Perspective is the product of a workshop on petrogenic OC at ETH Zurich held in September 2023, supported by a Royal Society International Exchange grant awarded to Daniel L. Evans at Cranfield University (IES\R3\213037) in collaboration with Thomas Blattmann at ETH ZurichAGU Advance
Kahneman's legacy in project management: improving decision-making and performance
Get PDFInternational Journal of Project Managemen
Capacity and impedance characteristics of the lithium-ion battery and mechanical properties of the battery pack under coupled temperature-vibration conditions: an experimental approach
Get PDFSince electric vehicles are subject to constant vibration and temperature fluctuations during operation, it is critical to understand the impact of these factors on the performance of batteries and battery enclosures. This study investigates the impact of vibration (random frequencies from 8 Hz to 200 Hz) and temperature (ranging from −20 °C to 60 °C in 10 °C increments) on lithium-ion batteries at varying states of charge (SOC, from 0 % to 100 % in 10 % intervals). A 3D-printed plastic enclosure was used for the battery pack to assess its mechanical performance under operational vibration. Analysis of the experimental data reveals that battery internal resistance shows an upward trend, with increases ranging from 0.1 mΩ to 0.5 mΩ under standard conditions and up to 1 mΩ at low temperatures after vibration. Battery capacity exhibited a slight decline after vibration, typically around 0.5 %, across most conditions. Temperature did not significantly impact the SOC response, with similar resistance and capacity trends observed across the temperature spectrum after vibration. For the battery pack, structural integrity was maintained under thermal and vibrational stress, as indicated by minimal changes in natural frequency (within 0.5 Hz). These results confirm the feasibility and potential of using 3D-printed battery enclosures in practical applications.Journal of Power Source
Proposal of a new category of lunar regolith simulants: reduced particle-density simulants that exhibit equivalent self-weight in Earth gravity to native regolith in lunar gravity
Get PDFCurrent “normal density” lunar regolith simulants used in Earth gravity can be viewed as a poor replication of bulk material handling behaviour of lunar regolith in lunar gravity. The six-times greater self-weight of such normal simulants on Earth compared to the Moon can be the viewed as the underlying cause. The use of such normal simulants in Earth gravity as part of technology development for lunar use may fail to adequately predict lunar behaviour and result in sub-optimal outcomes. This paper proposes a new class of reduced self-weight lunar regolith simulants to minimise this issue.
The current work elaborates the case for this new class of lunar regolith simulants with reduced particle density of one-sixth native lunar regolith resulting in reduced self-weight. To justify further this approach a series of studies are reported to highlight the expected differences between the current and proposed simulant uses. First, analytical arguments are used based around Jenike theory and the concept of Bond Number to highlight expected differences. Second, Discrete Element Method simulation is used show the expected difference in behaviour between the two simulants classes. Third, a laboratory breadboarded discharge hopper is used to demonstrate behaviour differences between normal and reduced self-weight stimulants. Additionally, a list of requirements for such reduced self-weight simulants is proposed.
The work concludes that the proposed new class of reduced particle density lunar simulants appears to have value and should be further pursued by the relevant communities.Acta Astronautic
Study on eco-efficiency optimization based on LCA-MFCA integration method: a case study on the cement industry
Get PDFCement production in China suffers from low eco-efficiency due to high coal and electricity consumption and substantial emissions. This study proposes a novel approach integrating Life Cycle Assessment (LCA) and Material Flow Cost Accounting (MFCA) to improve both economic and environmental performance. The method includes: (1) quantifying material, economic, and environmental losses using LCA and MFCA; (2) identifying improvement strategies through Pareto analysis, hypothesis testing, and expert input; and (3) validating results using an empirical case study. Applied to a cement company in Xinjiang, the approach increased eco-efficiency from 0.8737 to 1.0519, demonstrating synchronous economic and environmental gains. This is one of the first studies to apply LCA–MFCA integration in China’s cement sector.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: National Social Science Fund Project of China (No: 21BGL184).The Journal of Environment & Developmen
Cost-effective sensor-based digital twin for fused deposition modeling 3D printers
Get PDFIn a highly digitalized world, Digital Twin (DT) technology is becoming vital in manufacturing, especially in additive manufacturing. This research work presents cost-effective digital twin development and implementation for Fused Deposition Modeling (FDM) 3D printers. This developed system enhances real-time process monitoring, anomaly detection, and autonomous control through a logical approach. Sensor data that measures and tracks filament flow, vibrations, and nozzle position are processed in real-time for the detection of anomalies such as layer shifting, under- and over-extrusion, and excessive vibrations. Magnetic encoders enable monitoring the filament flow with 0.73% error, position sensors identify nozzle displacement to monitor layer shifts. The sensor data are stored in the Firebase and visualized in the Unity interface with a 500- 700 ms data lag. In contrast to traditional systems, this developed system works independently without the need for external hosts, providing a very low-cost, modular solution (less than $50) appropriate for small-scale applications. This research also addresses the gap in FDM 3D printers and sensor-based DT by demonstrating practical, real-time interventions for quality assurance in FDM processes.The research is funded by Nazarbayev University under the Faculty Development Competitive Research Grant Program (FDCRGP), Grant No. 11022021FD2904.International Journal of Computer Integrated Manufacturin