Search results for: Alternative fuel

Authors: Abhishek Sharma, Arnab Banerjee

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The research is intended to study the solar electric propulsion (SEP) technology for planetary missions. The main benefits of using solar electric propulsion for such missions are shorter flight times, more frequent target accessibility and the use of a smaller launch vehicle than that required by a comparable chemical propulsion mission. Energized by electric power from on-board solar arrays, the electrically propelled system uses 10 times less propellant than conventional chemical propulsion system, yet the reduced fuel mass can provide vigorous power which is capable of propelling robotic and crewed missions beyond the Lower Earth Orbit (LEO). The various thrusters used in the SEP are gridded ion thrusters and the Hall Effect thrusters. The research is solely aimed to study the ion thrusters and investigate the complications related to it and what can be done to overcome the glitches. The ion thrusters are used because they are found to have a total lower propellant requirement and have substantially longer time. In the ion thrusters, the anode pushes or directs the incoming electrons from the cathode. But the anode is not maintained at a very high potential which leads to divergence. Divergence leads to the charges interacting against the surface of the thruster. Just as the charges ionize the xenon gases, they are capable of ionizing the surfaces and over time destroy the surface and hence contaminate it. Hence the lifetime of thruster gets limited. So a solution to this problem is using substances which are not easy to ionize as the surface material. Another approach can be to increase the potential of anode so that the electrons don’t deviate much or reduce the length of thruster such that the positive anode is more effective. The aim is to work on these aspects as to how constriction of the deviation of charges can be done by keeping the input power constant and hence increase the lifetime of the thruster. Predominantly ring cusp magnets are used in the ion thrusters. However, the study is also intended to observe the effect of using solenoid for producing micro-solenoidal magnetic field apart from using the ring cusp magnetic field which are used in the discharge chamber for prevention of interaction of electrons with the ionization walls. Another foremost area of interest is what are the ways by which power can be provided to the Solar Electric Propulsion Vehicle for lowering and boosting the orbit of the spacecraft and also provide substantial amount of power to the solenoid for producing stronger magnetic fields. This can be successfully achieved by using the concept of Electro-dynamic tether which will serve as a power source for powering both the vehicle and the solenoids in the ion thruster and hence eliminating the need for carrying extra propellant on the spacecraft which will reduce the weight and hence reduce the cost of space propulsion.

Keywords: electro-dynamic tether, ion thruster, lifetime of thruster, solar electric propulsion vehicle

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Authors: Reem Osama Yousif Ali, Osama Yousif Ali Al Gibali

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Introduction: Balanced nutrition is undeniably essential for maintaining health, body functions, and integrity of cell metabolism; however, some sick patients cannot tolerate oral or enteral feeding to meet their nutritional needs, so partial or total parenteral nutrition (PN) may be the most suitable alternative route in such situations. Dietitians are fundamental personnel among the medical team to ensure the proper provision of PN service, which was introduced in Sudan in the 1980s. Objective: The study aimed to recognize the dietitians' awareness of parenteral nutrition and their role in providing this service in Sudan – Khartoum State. Methodology: Formulated questionnaire forms composed of twelve questions were distributed to the dietitians working in four tertiary level hospitals. Results: The majority (75%) of the responded dietitians had reasonable knowledge about the importance of PN, its advantages, and its indications. Sixty percent of them were mindful of the PN side effects. Most of the dietitians were aware of the different assessment measurements and PN calculations and were exposed in their clinical practice to patients who were in need of PN, but only a few of them (about 30%) had the actual chance to participate in the formulation and application of PN therapy. The unavailability of the multidisciplinary team, lack of the required equipment and financial support, and associated complications were basic obstacles to the provision of long-term PN service in Khartoum state hospitals. Conclusion: Although dietitians in Khartoum state hospitals have good information about PN definition, indications, accesses, and assessment measures, they do not have enough knowledge and clinical exposure that make them confident to provide the PN service. Establishing a few models of parenteral nutrition units in tertiary hospitals will be of great help, as well as providing the dietitian's training in the area of parenteral nutrition. Further study can explore more requirements to run this service.

Keywords: nutrition support, dietitian, Sudan, parenteral nutrition, nutrition support team

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Authors: Concetta Busacca, Leone Frusteri, Orazio Di Blasi, Alessandra Di Blasi

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The large-scale extension of renewable energy led, recently, to the development of efficient and low-cost electrochemical energy storage (EES) systems such as batteries. Although lithium-ion battery (LIB) technology is relatively mature, several issues regarding safety, cyclability, and high costs must be overcome. Thanks to the availability and low cost of sodium, sodium-ion batteries (NIB) have the potential to meet the energy storage needs of the large-scale grid, becoming a valid alternative to LIB in some energy sectors, such as the stationary one. However, important challenges such as low specific energy and short cyclic life due to the large radius of Na+ must be faced to introduce this technology into the market. As an important component of SIBs, cathode materials have a significant effect on the electrochemical performance of SIBs. Recently, sodium layer transition metal oxides, phosphates, and organic compounds have been investigated as cathode materials for SIBs. In particular, phosphate-based compounds such as NaₓMPO₄ (M= Fe, Co, Mn) have been extensively studied as cathodic polyanion materials due to their long cycle stability and appropriate operating voltage. Among these, an interesting cathode material is the NaMnPO₄ based one, thanks to the stability and the high redox potential of the Mn²⁺/Mn³⁺ ion pair (3÷4 V vs. Na+/Na), which allows reaching a high energy density. This work concerns with the synthesis of a composite material based on NaMnPO₄ and carbon nanofibers (NaMnPO₄-CNF) characterized by a mixed crystalline structure between the maricite and olivine phases and a self-standing manufacture obtained by electrospinning technique. The material was tested in a Na-ion battery coin cell in half cell configuration, and showed outstanding electrocatalytic performances with a specific discharge capacity of 125 mAhg⁻¹ and 101 mAhg⁻¹ at 0.3C and 0.6C, respectively, and a retention capacity of about 80% a 0.6C after 100 cycles.

Keywords: electrospinning, self standing materials, Na ion battery, cathode materials

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Authors: M. S. Yalfani, J. Kohzadi, P. Ghadimi, S. Sobhani, M. Ghadimi

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The use of oil and water-soluble corrosion inhibitors has been established in Iranian oil and gas production systems for a long time. Imidazoline and its derivatives are being extensively used which are known as conventional corrosion inhibitors. This type of product has shown significant performance and low side effects, so that could monopolize the market of inhibitors in this region. However, the price growth of imidazolines, as well as the development of new lower-cost components with similar or even higher performance than imidazoline, have influenced the exclusive market of imidazoline-based products. During the latest years, pyridine and its derivatives have challenged imidazoline due to their remarkable anticorrosive properties and lower prices as well. Recently, we presented a formulated water-soluble inhibitor based on pyridine - an alkyl pyridine quaternary salt (APQS) - which could successfully pass all lab tests and eventually succeeded in being applied in an offshore sweet oil pipeline. The product was able to achieve high corrosion protection (> 90 %) with the LPR technique at low dosages of 15-25 ppm under severe corrosion conditions. Moreover, the lab test results showed that the APQS molecule is able to form a strong and persistent bond with the metal surface. The product was later nominated to be evaluated through a field trial in an offshore sweet oil pipeline where PH2S < 0.05 psi and CO2 is 6.4 mol%. The three-month trial - extended to six months- resulted in remarkable internal protection obtained by continuous injection of 10 ppm inhibitor, which was as low as 1 mpy measured by both weight loss corrosion coupons and online ER probes. In addition, no side effects, such as tight emulsion and stable foaming, were observed. The residual of the corrosion inhibitor was measured at the end of the pipeline to ensure the full coverage of the inhibitor throughout the pipeline. Eventually, these promising results were able to convince the end user to consider pyridine-based inhibitors as a reliable alternative to imidazoline.

Keywords: corrosion inhibitor, pyridine, sweet oil, pipeline, offshore

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Authors: Kamil Jonski

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Last year vividly demonstrated, that populism and political instability can endanger democratic institutions in countries regarded as democratic transition champions (Poland) or cornerstones of liberal order (UK, US). So called ‘illiberal democracy’ is winning hearts and minds of voters, keen to believe that rule of strongman is a viable alternative to perceived decay of western values and institutions. These developments pose a serious threat to the democratic institutions (including rule of law), proven critical for both personal freedom and economic development. Although scholars proposed some structural explanations of the illiberal wave (notably focusing on inequality, stagnant incomes and drawbacks of globalization), they seem to have little predictive value. Indeed, events like Trump’s victory, Brexit or Polish shift towards populist nationalism always came as a surprise. Intriguingly, in the case of US election, simple rules like ‘Bread and Peace model’ gauged prospects of Trump’s victory better than pundits and pollsters. This paper attempts to compile set of indicators, in order to gauge various democracies’ vulnerability to populism, instability and pursuance of ‘illiberal’ projects. Among them, it identifies the gap between consensus assessment of institutional performance (as measured by WGI indicators) and citizens’ subjective assessment (survey based confidence in institutions). Plotting these variables against each other, reveals three clusters of countries – ‘predictable’ (good institutions and high confidence, poor institutions and low confidence), ‘blind’ (poor institutions, high confidence e.g. Uzbekistan or Azerbaijan) and ‘disillusioned’ (good institutions, low confidence e.g. Spain, Chile, Poland and US). It seems that this clustering – carried out separately for various institutions (like legislature, executive and courts) and blended with economic indicators like inequality and living standards (using PCA) – offers reasonably good watchlist of countries, that should ‘expect the unexpected’.

Keywords: illiberal democracy, populism, political instability, political risk measurement

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Authors: Helen L. Hein, Joachim Schwarte

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As a pillar of sustainable development, ecology has become an important milestone in research community, especially due to global challenges like climate change. The ecological performance of products can be scientifically conducted with life cycle assessments. In the construction sector, significant amounts of CO₂ emissions are assigned to the energy used for building heating purposes. Therefore, sustainable construction materials for insulating purposes are substantial, whereby aerogels have been explored intensively in the last years due to their low thermal conductivity. Therefore, the WALL-ACE project aims to develop an aerogel-based thermal insulating plaster that would achieve minor thermal conductivities. But as in the early stage of development phases, a lot of information is still missing or not yet accessible, the ecological performance of innovative products bases increasingly on uncertain data that can lead to significant deviations in the results. To be able to predict realistically how meaningful the results are and how viable the developed products may be with regard to their corresponding respective market, these deviations however have to be considered. Therefore, a classification method is presented in this study, which may allow comparing the ecological performance of modern products with already established and competitive materials. In order to achieve this, an alternative calculation method was used that allows computing with lower and upper bounds to consider all possible values without precise data. The life cycle analysis of the considered products was conducted with an interval arithmetic based calculation method. The results lead to the conclusion that the interval solutions describing the possible environmental impacts are so wide that the result usability is limited. Nevertheless, a further optimization in reducing environmental impacts of aerogels seems to be needed to become more competitive in the future.

Keywords: aerogel-based, insulating material, early development phase, interval arithmetic

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Authors: Yevheniia Varyvoda, Douglas Taren

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At the aggregate level, climate variability, the rising number of active violent conflicts, globalization and industrialization of agriculture, the loss in diversity of crop species, the increase in demand for agricultural production, and the adoption of healthy and sustainable dietary patterns are exacerbating factors of food system destabilization. The importance of pseudocereals to fuel and sustain resilient food systems is recognized by leading organizations working to end hunger, particularly for their critical capability to diversify livelihood portfolios and provide plant-sourced healthy nutrition in the face of systemic shocks and stresses. Amaranth, buckwheat, and quinoa are the most promising and used pseudocereals for ensuring food system resilience in the reality of climate change due to their high nutritional profile, good digestibility, palatability, medicinal value, abiotic stress tolerance, pest and disease resistance, rapid growth rate, adaptability to marginal and degraded lands, high genetic variability, low input requirements, and income generation capacity. The study provides the rationale and examples of advancing local and regional food systems' resilience by scaling up the utilization of amaranth, buckwheat, and quinoa along all components of food systems to architect indirect nutrition interventions and climate-smart approaches. Thus, this study aims to explore the drivers for ancient pseudocereal utilization, the potential resilience benefits that can be derived from using them, and the challenges and opportunities for pseudocereal utilization within the food system components. The PSALSAR framework regarding the method for conducting systematic review and meta-analysis for environmental science research was used to answer these research questions. Nevertheless, the utilization of pseudocereals has been slow for a number of reasons, namely the increased production of commercial and major staples such as maize, rice, wheat, soybean, and potato, the displacement due to pressure from imported crops, lack of knowledge about value-adding practices in food supply chain, limited technical knowledge and awareness about nutritional and health benefits, absence of marketing channels and limited access to extension services and information about resilient crops. The success of climate-resilient pathways based on pseudocereal utilization underlines the importance of co-designed activities that use modern technologies, high-value traditional knowledge of underutilized crops, and a strong acknowledgment of cultural norms to increase community-level economic and food system resilience.

Keywords: resilience, pseudocereals, food system, climate change

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Authors: Kevin Soubly, Kaysara Khatun

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This study applies the existing Middle-Out Perspective (MOP) as a complementing analytical alternative to the customary dichotomous options of top-down vs. bottom-up strategies of international development and commons governance. It expands the framework by applying it to a new context of land management and environmental change, enabling fresh understandings of decision making around land use. Using a case study approach in Central Kalimantan, Indonesia among a village of indigenous Dayak, this study explores influences from both internal and external middle actors, utilizing qualitative empirical evidence and incorporating responses across 25 village households and 11 key stakeholders. Applying the factors of 'agency' and 'capacity' specific to the MOP, this study demonstrates middle actors’ unique capabilities and criticality to change due to their influence across various levels of decision-making. Study results indicate that middle actors play a large role, both passively and actively, both directly and indirectly, across various levels of decision-making, perception-shaping, and commons governance. In addition, the prominence of novel 'passive' middle actors, such as the internet, can provide communities themselves with a level of agency beyond that provided by other middle actors such as NGOs and palm oil industry entities – which often operate at the behest of the 'top' or out of self-interest. Further, the study posits that existing development and decision-making frameworks may misidentify the 'bottom' as the 'middle,' raising questions about traditional development and livelihood discourse, strategies, and support, from agricultural production to forest management. In conclusion, this study provides recommendations including that current policy preconceptions be reevaluated to engage middle actors in locally-adapted, integrative manners in order to improve governance and rural development efforts more broadly.

Keywords: environmental management, governance, Indonesia, land use, middle actors, middle-out perspective

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Authors: Keyao Li, Sai On Cheung

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Incorporation of alternative dispute resolution (ADR) mechanism has been the main feature of current trend of construction project dispute resolution (CPDR). ADR approaches have been identified as efficient mechanisms and are suitable alternatives to litigation and arbitration. Moreover, the use of ADR in this multi-tiered dispute resolution process often leads to repeated evaluations of a same dispute. Multi-tiered CPDR may become a breeding ground for cognitive biases. When completed knowledge is not available at the early tier of construction dispute resolution, disputing parties may form preconception of the dispute matter or the counterpart. This preconception would influence their information processing in the subsequent tier. Disputing parties tend to search and interpret further information in a self-defensive way to confirm their early positions. Their imbalanced information collection would boost their confidence in the held assessments. Their attitudes would be hardened and difficult to compromise. The occurrence of cognitive bias, therefore, impedes efficient dispute settlement. This study aims to explore ways to minimize bias in CPDR. Based on a comprehensive literature review, three types of bias minimizing approaches were collected: strategy-based, attitude-based and process-based. These approaches were further operationalized into bias minimizing measures. To verify the usefulness and practicability of these bias minimizing measures, semi-structured interviews were conducted with ten CPDR third party neutral professionals. All of the interviewees have at least twenty years of experience in facilitating settlement of construction dispute. The usefulness, as well as the implications of the bias minimizing measures, were validated and suggested by these experts. There are few studies on cognitive bias in construction management in general and in CPDR in particular. This study would be the first of its type to enhance the efficiency of construction dispute resolution by highlighting strategies to minimize the biases therein.

Keywords: bias, construction project dispute resolution, minimization, multi-tiered, semi-structured interview

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Authors: Patrícia T. Souza, Marina Ansolin, Eduardo A. C. Batista, Antonio J. A. Meirelles, Matthieu Tubino

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Lipid oxidation is a major cause of the deterioration of the quality of the biodiesel, because the waste generated damages the engines. Among the main undesirable effects are the increase of viscosity and acidity, leading to the formation of insoluble gums and sediments which cause the blockage of fuel filters. The auto-oxidation is defined as the spontaneous reaction of atmospheric oxygen with lipids. Unsaturated fatty acids are usually the components affected by such reactions. They are present as free fatty acids, fatty esters and glycerides. To determine the oxidative stability of biodiesels, through the induction period, IP, the Rancimat method is used, which allows continuous monitoring of the induced oxidation process of the samples. During the oxidation of the lipids, volatile organic acids are produced as byproducts, in addition, other byproducts, including alcohols and carbonyl compounds, may be further oxidized to carboxylic acids. By the methodology developed in this work using ion chromatography, IC, analyzing the water contained in the conductimetric vessel, were quantified organic anions of carboxylic acids in samples subjected to oxidation induced by Rancimat. The optimized chromatographic conditions were: eluent water:acetone (80:20 v/v) with 0.5 mM sulfuric acid; flow rate 0.4 mL min-1; injection volume 20 µL; eluent suppressor 20 mM LiCl; analytical curve from 1 to 400 ppm. The samples studied were methyl biodiesel from soybean oil and unsaturated fatty acids standards: oleic, linoleic and linolenic. The induced oxidation kinetics curves were constructed by analyzing the water contained in the conductimetric vessels which were removed, each one, from the Rancimat apparatus at prefixed intervals of time. About 3 g of sample were used under the conditions of 110 °C and air flow rate of 10 L h-1. The water of each conductimetric Rancimat measuring vessel, where the volatile compounds were collected, was filtered through a 0.45 µm filter and analyzed by IC. Through the kinetic data of the formation of the organic anions of carboxylic acids, the formation rates of the same were calculated. The observed order of the rates of formation of the anions was: formate >>> acetate > hexanoate > valerate for the oleic acid; formate > hexanoate > acetate > valerate for the linoleic acid; formate >>> valerate > acetate > propionate > butyrate for the linolenic acid. It is possible to suppose that propionate and butyrate are obtained mainly from linolenic acid and that hexanoate is originated from oleic and linoleic acid. For the methyl biodiesel the order of formation of anions was: formate >>> acetate > valerate > hexanoate > propionate. According to the total rate of formation these anions produced during the induced degradation of the fatty acids can be assigned the order of reactivity: linolenic acid > linoleic acid >>> oleic acid.

Keywords: anions of carboxylic acids, biodiesel, ion chromatography, oxidation

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Authors: S. B. D. Samarasinghe, Malini Herath

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Participatory planning is a very important process for decision making and choosing the best alternative options for community welfare, development of the society and its interactions among community and professionals. People’s involvement is considered as the key guidance in participatory planning. Presently, Participatory planning is being used in many fields. It's not only limited to planning but also to disaster management, poverty, housing, etc. In the past, Disaster management practice was a top-down approach, but it raised many issues as it was converted to a bottom-up approach. There are several approaches that can aid disaster management. Community-Based Disaster Risk Management (CBDRM) is a very successful participatory approach to risk management that is often successfully applied by other disaster-prone countries. In the local context, CBDRM has been applied to prevent Diseases as well as to prevent disasters such as landslides, tsunamis and floods. From three years before, Sri Lanka has initiated the CBDRM approach to minimize landslide vulnerability. Hence, this study mainly focuses on the impact of CBDRM approaches on landslide hazards. Also to identify their successes and failures from both implementing parties and community. This research is carried out based on a qualitative method combined with a descriptive research approach. A successful framework was prepared via a literature review. Case studies were selected considering landslide CBDRM programs which were implemented by Disaster Management Center and National Building Research Organization in Badulla. Their processes were evaluated. Data collection is done through interviews and informal discussions. Then their ideas were quantified by using the Relative Effectiveness index. The resulting numerical value was used to rank the program effectiveness and their success, failures and impacting factors. Results show that there are several failures among implementing parties and the community. Overcoming those factors can make way for better conduction of future CBDRM programs.

Keywords: community-based disaster risk management, disaster management, preparedness, landslide

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Authors: F. Gallop, C. Ward, M. Zaky, M. Vaghela, R. Sabaratnam

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Nitrous oxide (N₂O) has been used in anaesthesia for over 150 years owing to advantageous physical and pharmacological properties. However, with a global warming potential of 310, we have an urgent responsibility to reduce its usage and emission. Anecdotal evidence in our hospital trust suggests minimal N₂O usage, yet our theatres receive a staggering supply. This warranted further investigation. We used a data collection tool to prospectively capture quantitative and qualitative data regarding N₂O cases during one week: this recorded demographics, N₂O indications, clinical management, and total N₂O consumption in litres. In addition, N₂O usage in dental sedation suites and paediatric theatres was separately quantified. Pipeline supply data was acquired from British Oxygen Company accounts. We captured 490 cases. 4% (n=19) used N₂O, 63% (n=12) of these in dental theatres. Common N₂0 indications were induction speed (37%) and rapidly increasing anaesthesia depth (32%). In adult cases, N₂O was always used intraoperatively rather than solely at induction. 74% (n=14) of anaesthetists reported environmental concern over using N₂O. The week’s total N₂O usage was 8109 litres, amounting to 421,668 litres annually. However, the annual N₂O pipeline supply is 2,997,000 litres; an enormous 1.8 million Kg of CO₂. Our results supportively demonstrate that the N₂O pipeline supply greatly exceeds its clinical use. Acknowledging clinical areas not audited, the discrepancy between supply and usage suggests approximately 2.5 million litres of yearly wastage. We consequently recommend terminating the N₂O pipeline supply in minimally used areas, eliminating 1.5 million Kg of CO₂ emissions. High usage clinical areas could consider portable N₂O cylinders as an alternative. In Sweden, N₂O destruction technology is routinely used to minimise CO₂ emissions. Our results support National Health System investment in similar infrastructure.

Keywords: anaesthesia, environment, medical gases, nitrous oxide, sustainability

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Authors: Mahfoudha Sid'Elemine

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The refugee resettlement process profoundly shapes the trajectories of individuals in their new host countries, exerting lasting effects on their long-term integration. Prevailing literature underscores the pivotal role of trust in facilitating successful refugee resettlement. However, this research challenges the notion of trust as universally paramount, contending that its significance is contingent upon variables such as the nature of resettlement programs and the diverse backgrounds and perspectives of refugees. Rather than advocating for a blanket approach to trust-building, this research contends that for certain resettlement programs, trust may prove counterproductive amidst resource constraints and tight service timelines. Moreover, trust may not uniformly emerge as a primary requisite for all refugees, presenting formidable challenges in its establishment. Focusing specifically on resettlement in the United States, this study illustrates how the temporal constraints of resettlement services, coupled with refugees' varied cultural experiences, can impede the cultivation of trust between aid workers and refugees. As an alternative paradigm, this research proposes an approach centered on fostering opportunities for reciprocal engagement, positioning refugees as active contributors within their newfound communities. Embracing reciprocity as the cornerstone of burgeoning relationships promises to fortify refugees' ties with the broader community, bolster their autonomy, and facilitate sustained integration over time. The research draws upon qualitative analyses of in-depth interviews conducted with a subset of resettled refugees, as well as aid workers and volunteers involved in refugee resettlement endeavors within Hampton Roads, Virginia, over the past decade. Through this nuanced examination, the study offers insights into the complexities of trust dynamics in refugee resettlement contexts and advocates for a paradigm shift towards reciprocal integration strategies.

Keywords: Resettlement programs, Trust dynamics, Reciprocity, Long-term integration

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Authors: Ishan Tank, Ashmita Rupal, Sanjay Kumar Sharma

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Concrete, a widely used building material, has cement as its main constituent. An excessive amount of emissions are released into the atmosphere during the manufacture of cement, which is detrimental to the environment. To minimize this problem, innovative materials like geopolymer mortar (GPM) seem to be a better alternative. By using fly ash-based geopolymer instead of standard cement mortar as a binding ingredient, this concept has been successfully applied to the building sector. The advancement of this technology significantly reduces greenhouse gas emissions and helps in source reduction, thereby minimizing pollution of the environment. In order to produce mortar and use this geopolymer mortar in the development of building materials, the current investigation is properly introducing this geopolymeric material, namely fly ash, as a binder in place of standard cement. In the domain of the building material industry, fly ash based geopolymer is a new and optimistic replacement for traditional binding materials because it is both environmentally sustainable and has good durability. The setting behaviour and strength characteristics of fly ash, when mixed with alkaline activator solution with varied concentration of sodium hydroxide solution, alkaline liquids mix ratio, and curing temperature, must be investigated, though, in order to determine its suitability and application in comparison with the traditional binding material, by activating the raw materials, which include various elements of silica and alumina, finer material known as geopolymer mortar is created. The concentration of the activator solution has an impact on the compressive strength of the geopolymer concrete formed. An experimental examination of compressive strength after 7, 14, and 28 days of fly ash-based geopolymer concrete is presented in this paper. Furthermore, the process of geopolymerization largely relies on the curing temperature. So, the setting time of Geopolymer mortar due to different curing temperatures has been studied and discussed in this paper.

Keywords: geopolymer mortar, setting time, flyash, compressive strength, binder material

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Authors: Rajkumar Ghosh

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Urban flooding is a common occurrence throughout Asia. Almost every city is vulnerable to urban floods in some fashion, and city people are particularly vulnerable. Pluvial and fluvial flooding are the most prominent causes of urban flooding in the Gomti Nagar region of Lucknow, Uttar Pradesh, India. The pluvial flooding is regarded to be less damaging because it is caused by heavy rainfall, Seasonal rainfall fluctuations, water flows off concrete infrastructures, blockages of the drainage system, and insufficient drainage capacity or low infiltration capacity. However, this study considers pluvial flooding in Lucknow to be a significant source of cumulative damage over time, and the risks of such events are increasing as a result of changes in ageing infrastructure, hazard exposure, rapid urbanization, massive water logging and global warming. As a result, urban flooding has emerged as a critical field of study. The popularity of analytical approaches to project the spatial extent of flood dangers has skyrocketed. To address future urban flood resilience, more effort is needed to enhance both hydrodynamic models and analytical tools to simulate risks under present and forecast conditions. Proper urban planning with drainage system and ample space for high infiltration capacity are required to reduce urban flooding. A better India with no urban flooding is a pipe dream that can be realized by putting household rooftop rainwater collection systems in every structure. According to the current study, domestic RTRWHs are strongly recommended as an alternative source of water, as well as to prevent surface runoff and urban floods in this region of Lucknow, urban areas of India.

Keywords: rooftop rainwater harvesting, urban flood, pluvial flooding, fluvial flooding

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Authors: Virginia Venturini, Elisabet Walker, Aylen Carrasco-Millan

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Latin America stands at the front of climate change impacts, with forecasts projecting accelerated temperature and sea level rises compared to the global average. These changes are set to trigger a cascade of effects, including coastal retreat, intensified droughts in some nations, and heightened flood risks in others. In Argentina, wildfires historically affected forests, but since 2004, wetland fires have emerged as a pressing concern. By 2021, the wetlands of the Paraná River faced a dangerous situation. In fact, during the year 2021, a high-risk scenario was naturally formed in the wetlands of the Paraná River, in Argentina. Very low water levels in the rivers, and excessive standing dead plant material (fuel), triggered most of the fires recorded in the vast wetland region of the Paraná during 2020-2021. During 2008 fire events devastated nearly 15% of the Paraná Delta, and by late 2021 new fires burned more than 300,000 ha of these same wetlands. Therefore, the goal of this work is to explore remote sensing tools to monitor environmental conditions and the severity of prescribed burns in the Paraná River wetlands. Thus, two prescribed burning experiments were carried out in the study area (31°40’ 05’’ S, 60° 34’ 40’’ W) during September 2023. The first experiment was carried out on Sept. 13th, in a plot of 0.5 ha which dominant vegetation were Echinochloa sp., and Thalia, while the second trial was done on Sept 29th in a plot of 0.7 ha, next to the first burned parcel; here the dominant vegetation species were Echinochloa sp. and Solanum glaucophyllum. Field campaigns were conducted between September 8th and November 8th to assess the severity of the prescribed burns. Flight surveys were conducted utilizing a DJI® Inspire II drone equipped with a Sentera® NDVI camera. Then, burn severity was quantified by analyzing images captured by the Sentera camera along with data from the Sentinel 2 satellite mission. This involved subtracting the NDVI images obtained before and after the burn experiments. The results from both data sources demonstrate a highly heterogeneous impact of fire within the patch. Mean severity values obtained with drone NDVI images of the first experience were about 0.16 and 0.18 with Sentinel images. For the second experiment, mean values obtained with the drone were approximately 0.17 and 0.16 with Sentinel images. Thus, most of the pixels showed low fire severity and only a few pixels presented moderated burn severity, based on the wildfire scale. The undisturbed plots maintained consistent mean NDVI values throughout the experiments. Moreover, the severity assessment of each experiment revealed that the vegetation was not completely dry, despite experiencing extreme drought conditions.

Keywords: prescribed-burn, severity, NDVI, wetlands

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Authors: Abdullah Ansari, Sinika Rambaran, Sirpaul Jaikishun

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Vermiwash could be used to enhance plant productivity and resistance to some harmful plant pathogens, as well as provide benefit through the disposal of waste matter. Alternaria rot caused by the fungus Alternaria alternata (Fr.) Keissl., is a common soil-borne pathogen that results in postharvest fruit rot of cucumbers, peppers and other cash crops. The production and distribution of Cucumis sativus L. (cucumber) could be severely affected by Alternaria rot. Fungicides are the traditional treatment however; they are not only expensive but can also cause environmental and health problems. Vermiwash was prepared from various medicinal plants (Ocimum tenuiflorum L. {Tulsi}, Azadirachta indica A. Juss. {neem}, Cymbopogon citratus (DC. ex Nees) Stapf. {lemon grass} and Oryza sativa L. {paddy straw} and applied, in vitro, to A. alternata to investigate their effectiveness as organic alternatives to traditional fungicides. All of the samples of vermiwash inhibited the growth of A. alternata. The inhibitive effects on the fungus appeared most effective when A. indica and O. tenuiflorum were used in the production of the vermiwash. Using the serial dilution method, vermiwash from O. tenuiflorum showed the highest percent of inhibition (93.2%), followed by C. citratus (74.7%), A. indica (68.7%), O. sativa, combination, and combination without worms. Using the sterile disc diffusion method, all of the samples produced zones of inhibition against A. alternata. Vermiwash from A. indica produced a zone of inhibition, averaging 15.3mm, followed by O. tenuiflorum (14.0mm), combination without worms, combination, C. citratus and O. sativa. Nystatin produced a zone of inhibition of 10mm. The results indicate that vermiwash is not simply an organic alternative to more traditional chemical fungicides, but it may in fact be a better and more effective product in treating certain fungal plant infections, particularly A. alternata.

Keywords: vermiwash, earthworms, soil, bacteria, alternaria alternata, antifungal, antibacterial

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Authors: Checkfaith I. Aizebeoje, Temitope O. Lawal, Bolanle A. Adeniyi

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The overuse and abuse of antibiotics in treating zoonotic infections in humans and opportunistic infections in rabbit has contributed to the increase in antimicrobial drug resistance, therefore, an alternative to antibiotics is needed in treating these infections. The study was carried out to determine the antimicrobial activity of lactic acid bacteria (LAB) isolated from rabbit’s faeces against multidrug-resistant (MDR) pathogens isolated from the same rabbit. Twelve faecal samples and twelve swabs from fur samples were randomly collected aseptically from apparently healthy rabbits from Ajibode, Ibadan and University of Ibadan research farm in Ibadan, Oyo state, Nigeria. Lactic acid bacteria and multidrug-resistant pathogens were isolated using appropriate agar media and identified by partial sequencing of the 16SrRNA gene. Antibiotic susceptibility pattern of isolated bacteria and LAB were determined by the agar diffusion method. The antibacterial activity of the LAB against the test pathogens was determined using the agar overlay and agar diffusion methods. The pathogens Myroides gitamensis, Citrobacter rodentium, Acinetobacter johnsonii, Enterobacter oryzendophyticus and Serratia marcescens as well as twenty-eight (28) species of LAB belonging to Acetobacter and Lactobacillus genera were identified and characterized. Lactobacillus plantarum had the highest (60.71%) occurrence of the LAB. Viable cells and cell free supernatant (CFS) of isolated LAB inhibited the growth of the test organisms with the largest zone of inhibition (40 mm) produced by Lactobacillus plantarum against Citrobacter rodentium. This study showed that LAB from rabbit possess considerable antibacterial activity against multidrug-resistant bacteria from the same environment.

Keywords: antibacterial activities, cell-free supernatant, lactic acid bacteria; multidrug-resistant pathogens, rabbits’ faeces

Procedia PDF Downloads 133

Authors: Pradeep Kulshrestha, Maulana Ayoub Ali

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The level of penetration of Islamic banking products and services has recorded a reasonable growth at an exponential rate in many parts of the world. There are many factors which have contributed to this growth including, but not limited to the rapid growth of number of Muslims who are uncomfortable with the conventional ways of banking, interest and higher interest rates scheduled by conventional banks and financial institutions as well as the financial inclusion campaign conducted in many countries. The system is facing legal challenges which open the research fdoor for practitioners and academicians for the sake of finding out solutions to those challenges. This paper tries to investigate the development of the Islamic banking system in the United Kingdom (UK), Saudi Arabia, Malaysia, Iran, Kenya, Nigeria and Uganda in order to understand the modalities which have been employed to run an Islamic banking system in the aforementioned countries. The methodology which has been employed in doing this research paper is Doctrinal, of which legislations, policies and other legal tools have been carefully studied and analysed. Again, papers from academic journals, books and financial reports have been deeply analysed for the purpose of enriching the paper and come up with a tangible results. The paper found that in Asia, Malaysia has created the smoothest legal platform for Islamic banking system to work properly in the country. The United Kingdom has tried harder to smooth the banking system without affecting the conventional banking methods and without favouring the operations of Islamic banks. It also tries harder to make UK as an Islamic banking and finance hub in Europe. The entire banking system in Iran is Islamic, while Nigeria has undergone several legal reforms to suit Islamic banking system in the country. Kenya and Uganda are at a different pace in making Islamic Banking system work alongside the conventional banking system.  

Keywords: shariah, Islamic banking, law, alternative banking

Procedia PDF Downloads 151

Authors: Nora Kuiper, Candace Rowell, Hugues Preud'Homme, Basem Shomar

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As the global dependence on seawater desalination as a primary drinking water resource increases, a unique class of secondary pollutants is emerging. The presence of bromide salts in seawater may result in increased levels of bromine and brominated byproducts in drinking water. The State of Qatar offers a unique setting to study these pollutants and their impacts on consumers as the country is 100% dependent on seawater desalination to supply municipal tap water and locally produced bottled water. Tap water (n=115) and bottled water (n=62) samples were collected throughout the State of Qatar and analyzed for a suite of inorganic and organic compounds, including 54 volatile organic compounds (VOCs), with an emphasis on brominated byproducts. All VOC identification and quantification was completed using a Bruker Scion GCMSMS with static headspace technologies. A risk survey tool was used to collect information regarding local consumption habits, health outcomes and perception of water sources for adults and children. This study is the first of its kind in the country. Dibromomethane, bromoform, and bromobenzene were detected in 61%, 88% and 2%, of the drinking water samples analyzed. The levels of dibromomethane ranged from approximately 100-500 ng/L and the concentrations of bromoform ranged from approximately 5-50 µg/L. Additionally, bromobenzene concentrations were 60 ng/L. The presence of brominated compounds in drinking water is a public health concern specific to populations using seawater as a feed water source and may pose unique risks that have not been previously studied. Risk assessments are ongoing to quantify the risks associated with prolonged consumption of disinfection byproducts; specifically the risks of brominated trihalomethanes as the levels of bromoform found in Qatar’s drinking water reach more than 60% of the US EPA’s Maximum Contaminant Level of all THMs.

Keywords: brominated byproducts, desalination, trihalomethanes, risk assessment

Procedia PDF Downloads 428

Authors: Aminu Abdullahi Isyaku

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Semi-arid Bornu basin in northeast Nigeria is characterised with flat topography, thick cover sediments and lack of continuous bedrock outcrops discernible for field geology. This paper presents the methodology for the characterisation of neotectonic surface structures and surface lithology in the north-eastern Bornu basin in northeast Nigeria as an alternative approach to field geological mapping using free multispectral Landsat 7 ETM+, SRTM DEM and ASAR Earth Observation datasets. Spectral lithological mapping herein developed utilised spectral discrimination of the surface features identified on Landsat 7 ETM+ images to infer on the lithology using four steps including; computations of band combination images; band ratio images; supervised image classification and inferences of the lithological compositions. Two complementary approaches to lineament mapping are carried out in this study involving manual digitization and automatic lineament extraction to validate the structural lineaments extracted from the Landsat 7 ETM+ image mosaic covering the study. A comparison between the mapped surface lineaments and lineament zones show good geospatial correlation and identified the predominant NE-SW and NW-SE structural trends in the basin. Topographic profiles across different parts of the Bama Beach Ridge palaeoshorelines in the basin appear to show different elevations across the feature. It is determined that most of the drainage systems in the northeastern Bornu basin are structurally controlled with drainage lines terminating against the paleo-lake border and emptying into the Lake Chad mainly arising from the extensive topographic high-stand Bama Beach Ridge palaeoshoreline.

Keywords: Bornu Basin, lineaments, spectral lithology, tectonics

Procedia PDF Downloads 139

Authors: Radegunda Kessy, Justus Ochieng, Victor Afari-Sefa, Takemore Chagomoka, Ngoni Nenguwo

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Vegetables are excellent sources of dietary fiber, vitamins, and minerals which constitute an indispensable constituent of diets, but in Tanzania and other Sub-Saharan African countries, they are not readily available all year round due to seasonal variations in the production cycle. Drying of vegetables is one of the traditional methods for food preservation known to man. The Dodoma and Singida regions of Tanzania are characterized by semi-arid agro-climate, thereby experiencing short seasonal supply of fresh vegetables followed by long drought in which dried vegetables become an alternative to meet high household demands. A primary survey of 244 of rural consumers was carried out to understand how knowledge, attitudes, and perceptions of rural consumers affect consumption of dried vegetables. The sample respondents were all found to be aware of open sun drying of vegetables while less than 50% of them were aware of solar-dried vegetables. Consumers were highly concerned with the hygiene, nutritional values, taste, drying method, freshness, color of dried vegetables, timely availability and easiness of cooking as important factors they consider before they purchase dried vegetables. Logit model results show that gender, income, years of consuming dried vegetables, awareness of the importance of solar dried vegetables vis-à-vis sun-dried alternatives and employment status influenced rural consumer’s decision to purchase dried vegetables. Preference on dried vegetables differs across the regions which are also important considerations for any future planned interventions. The findings imply that development partners and policymakers need to design better social marketing and promotion techniques for the enhanced adoption of solar drying technology, which will greatly improve the quality and utilization of dried vegetables by target households.

Keywords: dried vegetables, postharvest management, sun drying, solar drying

Procedia PDF Downloads 198

Authors: Odaleia de O. Farias, Suzelene C. Marinho, Ecleidson B. Fragoso, Daniel S. Lima, Francisco R. S. Lira, Lara S. Araújo, Gabriel dos S. D. Soares

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In populous cities, prehospital care services that use vehicles alternative to ambulances are needed in order to reduce costs and improve response time to occurrences in areas with large concentration of people, such as leisure and tourism spaces. In this context, it was implanted a program called BIKE VIDA, that is innovative quick access and assistance program. The aim of this study is to describe the implantation and initial profile of occurrences performed by an urgency/emergency pre-hospital care service through paramedics on bicycles. It is a cross-sectional, descriptive study carried out in the city of Fortaleza, Ceara, Brazil. The data included service records from July to August 2017. Ethical aspects were respected. The service covers a perimeter of 4.5 km, divided into three areas with perimeter of 1.5 km for each paramedic, attending from 5 am to 9 pm. Materials transported by bicycles include External Automated Defibrillator - DEA, portable oxygen, oximeter, cervical collar, stethoscope, sphygmomanometer, dressing and immobilization materials and personal protective equipment. Occurrences are requested directly by calling the emergency number 192 or through direct approach to the professional. In the first month of the program, there were 93 emergencies/urgencies, mainly in the daytime period (71,0%), in males (59,7%), in the age range of 26 to 45 years (46,2%). The main nature was traumatic incidents (53.3%). Most of the cases (88,2%) did not require ambulance transport to the hospital, and there were two deaths. Pre-hospital service through bicycles is an innovative strategy in Brazil and has shown to be promising in terms of reducing costs and improving the quality of the services offered.

Keywords: emergency, response time, prehospital care, urgency

Procedia PDF Downloads 197

Authors: Farouq Sule Garo, Yahaya Yusuf

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The purpose of this study is to investigate why there is a general lack of successful adoption of sustainable energy in Nigeria. This is particularly important given the current global campaign for net-zero emissions. The 26th United Nations Conference of the Parties (COP26), held in 2021, was hosted by the UK, in Glasgow, where, amongst other things, countries including Nigeria agreed to a zero emissions pact. There is, therefore, an obligation on the part of Nigeria for transition from fossil fuel-based economy to a sustainable net-zero emissions economy. The adoption of renewable energy is fundamental to achieving this ambitious target if decarbonisation of economic activities were to become a reality. Nigeria has an abundance of sources of renewable energy and yet there has been poor uptake and where attempts have been made to develop and harness renewable energy resources, there has been limited success. It is not entirely clear why this is the case. When analysts allude to corruption as the reason for failure for successful adoption of renewable energy or project implementation, it is arguable that corruption alone cannot explain the situation. Therefore, there is the need for a thorough investigation into the underlying issues surrounding poor uptake of renewable energy in Nigeria. This pilot study, drawing upon stakeholders’ theory, adopts a multi-stakeholder’ perspectives to investigate the influence and impacts of economic, political, technological, social factors in adoption of renewable energy in Nigeria. The research will also investigate how these factors shape (or fail to shape) strategies for achieving successful adoption of renewable energy in the country. A qualitative research methodology has been adopted given the nature of the research requiring in-depth studies in specific settings rather than a general population survey. There will be a number of interviews and each interview will allow thorough probing of sources. This, in addition to the six interviews that have already been conducted, primarily focused on economic dimensions of the challenges in adoption of renewable energy. The six participants in these initial interviews were all connected to the Katsina Wind Farm Project that was conceived and built with the view to diversifying Nigeria's energy mix and capitalise on the vast wind energy resources in the northern region. The findings from the six interviews provide insights into how the economic factors impacts on the wind farm project. Some key drivers have been identified, including strong governmental support and the recognition of the need for energy diversification. These drivers have played crucial roles in initiating and advancing the Katsina Wind Farm Project. In addition, the initial analysis has highlighted various challenges encountered during the project's implementation, including financial, regulatory, and environmental aspects. These challenges provide valuable lessons that can inform strategies to mitigate risks and improve future wind energy projects.

Keywords: challenges in adoption of renewable energy, economic factors, net-zero emission, political factors

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Authors: Farzaneh Bahrami

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Different indicators, such as modal shares in mobility practices or car ownership, may suggest that the century of car dominance - at least in Europe and North America - is already behind us. If the emergence of the car had radical spatial and social consequences, what would be the implications of its gradual disappearance - which could be expected in the context of ecological consciousness, economic and energetic constraints as a result of both urban policies as well as lifestyle choices? To what extend shall urban experts account for this limited but visible transition from car-dominated systems towards alternative models of mobility in which the individual-motorized mobility (car) is not central; what models of urbanity could be imagined to support such a transformation? We have examined a selection of projects at different scales and within different contexts - new planned cities, dense urban areas or territories of dispersion – whose visions involve a significant shift from the current car system. We have been looking into their tools, strategies and different measures of car reduction, as well as their varied approaches to public space as an inevitable corollary to this change. The car’s dominance was formerly questioned by advocates of public space, rather than through interests in ecological urban design or other urban planning concerns. In the 60s already a universal longing for the qualities of traditional urban space led to a critique of the proliferation of fast roads, and thus the car’s colonization of everyday life. Reclamation of public space as the city’s quintessential social territory reappears today in contemporary discourses and reinforces the shift-provoking trends towards a new urbanity freed from car dominance. In a hypothetical process of the progressive phasing-out of the car, we shall expect fundamental transformations in spatial practices of the city, accompanied by the physical configuration of its public spaces. What will be the main characteristics of the new emerging spaces of sociability and where shall we encounter them? This contribution is an ongoing research within the framework of Post-Car World, an interdisciplinary project that explores the future of mobility through the role of the car.

Keywords: mobility, urbanity, future visions, public space

Procedia PDF Downloads 370

Authors: Chengliang Xie, Jinhyun Ryu, Hyun Joon Kim, Gyeong Jae Cho, Wan Sung Choi, Sang Soo Kang, Kye Man Cho, Dong Hoon Lee

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Obesity has become a global health problem and a source of major metabolic diseases like type-2 diabetes, hypertension, heart disease, nonalcoholic fatty liver and cancer. Synthetic anti-obesity drugs are effective but very costly and with undesirable side effects, so natural products such as soybean are needed as an alternative for obesity treatment. Lactobacillus Plantarum P1201is a probiotic bacterial strain reported to produce conjugated linoleic acid (CLA) and increase the ratio of aglycone-isoflavone of soybean, both of which have anti-obesity effect. In this study, the anti-obesity effect of the fermented soybean extract with P1201 (FSE) will be evaluated compared with that of the soybean extract (SE) by 3T3-L1 cells as an in vitro model of adipogenesis. 3T3-L1 cells were treated with SE and FSE during the nine days of the differentiation, lipid accumulation was evaluated by oil-red staining and triglyceride content and the mRNA expression level of adipogenic or lipogenic genes were analyzed by RT-PCR and qPCR. The results showed that formation of lipid droplets in differentiated 3T3-L1 cells was inhibited and triglyceride content was reduced by 23.1% after treated with 1000 μg/mL of FSE compared with control. For SE-treated groups, no delipidating effect was observed. The effect of FSE on adipogenesis inhibition can be attributed to the down-regulation of mRNA expressionof CCAAT/enhancer binding protein (C/EBP-α), lipoprotein lipase (LPL), adiponectin, adipocyte fatty acid-binding protein (aP2), fatty acid synthesis (FAS) and CoA carboxylase (ACC). Our results demonstrated that the anti-obesity effect of soybean can be improved by fermentation with P1201, and P1201can be used as a potential probiotic bacterial strain to produce natural anti-obesity food.

Keywords: fermentation, Lactobacillus plantarum P1201, obesity, soybean

Procedia PDF Downloads 333

Authors: Pradeep Kulshrestha, Maulana Ayoub Ali

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The concept of financial inclusion has been tabled in the whole world where practitioners, academicians, policy makers and economists are working hard to look for the best possible opportunities in order to enable the whole society to be in the banking cycle. The Islamic banking system is considered to be one of the said opportunities. Countries like the United Kingdom, United States of America, Malaysia, Saudi Arabia, the whole of the United Arab Emirates and many African countries have accommodated the aspect of Islamic banking in the conventional banking system as one of the financial inclusion strategies. This paper tries to analyse the current state of affairs of the Islamic Banking system in Tanzania in order to understand the improvement of the provision of Islamic banking products and services in the said country. The paper discusses the historical background of the banking system in Tanzania, the level of penetration of banking products and services and the coming of the Islamic banking system in the country. Furthermore, the paper discusses banking regulatory bodies, legal instruments governing banking operations as well as number of legal challenges facing Islamic banking operations in the country. Following a critical literature review, the paper discovered that there is no legal instrument which talks about the introduction and provision of Islamic banking system in Tanzania. Furthermore, the Islamic banking system was considered as a banking product which is absolutely incorrect because Islamic banking is considered to be as a banking system of its own. In addition to that, it has been discovered that lack of a proper regulatory system and legal instruments to harmonize the conventional and Islamic banking systems has resulted in the closure of one Islamic window in the country, which in the end affects the credibility of the newly introduced banking system. In its conclusive remarks, the paper suggests that Tanzania should work on all legal challenges affecting the smooth operations of the Islamic banking system. This can be in a way of adopting various Islamic banking legal models which are used in countries like Malaysia and others, or a borrowing legal harmonization process which has been adopted by the UK, Uganda, Nigeria and Kenya.

Keywords: Islamic banking, Islamic windows, regulations, banks

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Authors: Seyede Sanaz Seyedebrahimi, Shima Rahimi, Shohreh Fakhari, Ali Jalili

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Background: CXCR4, as a chemokine receptor, plays well-known roles in various types of cancers. Several studies have been conducted to overcome CXCR4 axis acts in multiple myeloma (MM) pathogenesis and progression. Dexamethasone, a standard treatment for multiple myeloma, has been shown to increase CXCR4 levels in multiple myeloma cell lines. Herein, we focused on the effects of metformin and dexamethasone on CXCR4 at the cellular level and the migration rate of cell lines after exposure to a combination compared to single-agent models. Materials and Method: Multiple myeloma cell lines (U266 and RPMI8226) were cultured with different metformin and dexamethasone concentrations in single-agent and combination models. The simultaneous combination doses were calculated by CompuSyn software. Cell surface and mRNA expression of CXCR4 were determined using flow cytometry and the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay, respectively. The Transwell cell migration assay evaluated the migration ability. Results: In concurred with previous studies, our results showed a dexamethasone up-regulation effect on CXCR4 in a dose-dependent manner. Although, the metformin single-agent model could reduce CXCR4 expression of U266 and RPMI8226 in cell surface and mRNA expression level. Moreover, the administration of metformin and dexamethasone simultaneously exerted a higher suppression effect on CXCR4 expression than the metformin single-agent model. The migration rate through the combination model's matrigel membrane was remarkably lower than the metformin and dexamethasone single-agent model. Discussion: According to our findings, the combination of metformin and dexamethasone effectively inhibited dexamethasone-induced CXCR4 expression in multiple myeloma cell lines. As a result, metformin may be counted as an alternative medicine combined with other chemotherapies to combat multiple myeloma. However, more research is required.

Keywords: CXCR4, dexamethasone, metformin, migration, multiple myeloma

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Authors: Azadeh Yasari, Michael Ganzle, Stephen Strelkov, Nuanyi Liang, Jonathan Curtis, Nat N. V. Kav

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Pathogenic fungi cause significant yield losses and quality reductions to major crops including wheat, canola, and barley. Toxic metabolites produced by phytopathogenic fungi also pose significant risks to animal and human health. Extensive application of synthetic fungicides is not a sustainable solution since it poses risks to human, animal and environmental health. Unsaturated fatty acids may provide an environmentally friendly alternative because of their direct antifungal activity against phytopathogens as well as through the stimulation of plant defense pathways. The present study assessed the in vitro and in vivo efficacy of two hydroxy fatty acids, coriolic acid and ricinoleic acid, against the phytopathogens Fusarium graminearum, Pyrenophora tritici-repentis, Pyrenophora teres f. teres, Sclerotinia sclerotiorum, and Leptosphaeria maculans. Antifungal activity of coriolic acid and ricinoleic acid was evaluated using broth micro-dilution method to determine the minimum inhibitory concentration (MIC). Results indicated that both ricinoleic acid and coriolic acid showed antifungal activity against phytopathogens, with the strongest inhibitory activity against L. maculans, but the MIC varied greatly between species. An antifungal effect was observed for coriolic acid in vivo against pathogenic fungi of wheat and barley. This effect was not correlated to the in vitro activity because ricinoleic acid with equivalent in vitro antifungal activity showed no protective effect in vivo. Moreover, neither coriolic acid nor ricinoleic acid controlled fungal pathogens of canola. In conclusion, coriolic acid inhibits some phytopathogens in vivo and may have the potential to be an effective crop protection agent.

Keywords: coriolic acid, minimum inhibitory concentration, pathogenic fungi, ricinoleic acid

Procedia PDF Downloads 177

Authors: Rachmat Mauludin, Nurmazidah

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Background and purpose: Famotidine is an H2 receptor blocker. Absorption orally is rapid enough, but famotidine can be degraded by stomach acid causing dose reduction until 35.8% after 50 minutes. This drug also undergoes first-pass metabolism which reduced its bio availability only until 40-50%. To overcome these problems, Solid Lipid Nano particles (SLNs) as alternative delivery systems can be formulated. SLNs is a lipid-based drug delivery technology with 50-1000 nm particle size, where the drug incorporated into the bio compatible lipids and the lipid particles are stabilized using appropriate stabilizers. When the particle size is 200 nm or below, lipid containing famotidine can be absorbed through the lymphatic vessels to the subclavian vein, so first-pass metabolism can be avoided. Method: Famotidine SLNs with various compositions of stabilizer was prepared using a high-speed homogenization and sonication method. Then, the particle size distribution, zeta potential, entrapment efficiency, particle morphology and in vitro release profiles were evaluated. Optimization of sonication time also carried out. Result: Particle size of SLN by Particle Size Analyzer was in range 114.6 up to 455.267 nm. Ultrasonicated SLNs within 5 minutes generated smaller particle size than SLNs which was ultrasonicated for 10 and 15 minutes. Entrapment efficiency of SLNs were 74.17 up to 79.45%. Particle morphology of the SLNs was spherical and distributed individually. Release study of Famotidine revealed that in acid medium, 28.89 up to 80.55% of famotidine could be released after 2 hours. Nevertheless in basic medium, famotidine was released 40.5 up to 86.88% in the same period. Conclusion: The best formula was SLNs which stabilized by 4% Poloxamer 188 and 1 % Span 20, that had particle size 114.6 nm in diameter, 77.14% famotidine entrapped, and the particle morphology was spherical and distributed individually. SLNs with the best drug release profile was SLNs which stabilized by 4% Eudragit L 100-55 and 1% Tween 80 which had released 36.34 % in pH 1.2 solution, and 74.13% in pH 7.4 solution after 2 hours. The optimum sonication time was 5 minutes.

Keywords: famotodine, SLN, high speed homogenization, particle size, release study

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