Search results for: intuitionistic fuzzy cycle

Authors: Anna Carolina De Paula Sermarini, Rodrigo Flora Calili

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Energy Efficiency (EE) needs investments, new technologies, greater awareness and management on the side of citizens and organizations, and more planning. However, this issue is usually remembered and discussed only in moments of energy crises, and opportunities are missed to take better advantage of the potential of EE in the various sectors of the economy. In addition, there is little concern about the subject among the less favored classes, especially in low-income communities. Accordingly, this article presents suggestions for public policies that aim to increase EE for low-income housing and communities based on international and national experiences. After reviewing the literature, eight policies were listed, and to evaluate them; a multicriteria decision model was developed using the AHP (Analytical Hierarchy Process) and TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) methods, combined with fuzzy logic. Nine experts analyzed the policies according to 9 criteria: economic impact, social impact, environmental impact, previous experience, the difficulty of implementation, possibility/ease of monitoring and evaluating the policies, expected impact, political risks, and public governance and sustainability of the sector. The results found in order of preference are (i) Incentive program for equipment replacement; (ii) Community awareness program; (iii) EE Program with a greater focus on low income; (iv) Staggered and compulsory certification of social interest buildings; (v) Programs for the expansion of smart metering, energy monitoring and digitalization; (vi) Financing program for construction and retrofitting of houses with the emphasis on EE; (vii) Income tax deduction for investment in EE projects in low-income households made by companies; (viii) White certificates of energy for low-income. First, the policy of equipment substitution has been employed in Brazil and the world and has proven effective in promoting EE. For implementation, efforts are needed from the federal and state governments, which can encourage companies to reduce prices, and provide some type of aid for the purchase of such equipment. In second place is the community awareness program, promoting socio-educational actions on EE concepts and with energy conservation tips. This policy is simple to implement and has already been used by many distribution utilities in Brazil. It can be carried out through bids defined by the government in specific areas, being executed by third sector companies with public and private resources. Third on the list is the proposal to continue the Energy Efficiency Program (which obliges electric energy companies to allocate resources for research in the area) by suggesting the return of the mandatory investment of 60% of the resources in projects for low income. It is also relatively simple to implement, requiring efforts by the federal government to make it mandatory, and on the part of the distributors, compliance is needed. The success of the suggestions depends on changes in the established rules and efforts from the interested parties. For future work, we suggest the development of pilot projects in low-income communities in Brazil and the application of other multicriteria decision support methods to compare the results obtained in this study.

Keywords: energy efficiency, low-income community, public policy, multicriteria decision making

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Authors: Elena Pucci, Margherita Tufarelli, Leonardo Giliberti

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As central for human and social development of the future, sustainability is becoming a recurring theme also in the fashion industry, where the need to explore new possible directions aimed at achieving sustainability goals and their communication is rising. Scholars have been devoted to the overall environmental impact of the textile and fashion industry, which, emerging as one of the world’s most polluting, today concretely assumes the need to take the path of sustainability in both products and production processes. Every day we witness the impact of our consumption, showing that the sustainability concept is as vast as complex: with a sometimes ambiguous definition, sustainability can concern projects, products, companies, sales, packagings, supply chains in relation to the actors proximity as well as traceability, raw materials procurement, and disposal. However, in its primary meaning, sustainability is the ability to maintain specific values and resources for future generations. The contribution aims to address sustainability in the fashion system as a layered problem that requires substantial changes at different levels: in the fashion product (materials, production processes, timing, distribution, and disposal), in the functioning of the system (life cycle, impact, needs, communication) and last but not least in the practice of fashion design which should conceive durable, low obsolescence and possibly demountable products. Moreover, consumers play a central role for the growing awareness, together with an increasingly strong sensitivity towards the environment and sustainable clothing. Since it is also a market demand, undertaking significant efforts to achieve total transparency and sustainability in all production and distribution processes is becoming fundamental for the fashion system. Sustainability is not to be understood as purely environmental but as the pursuit of collective well-being in relation to conscious production, human rights, and social dignity with the aim to achieve intelligent, resource, and environmentally friendly production and consumption patterns. Assuming sustainability as a layered problem makes the role of communication crucial to convey scientific or production specific content so that people can obtain and interpret information to make related decisions. Hence, if it is true that “what designers make becomes the future we inhabit'', design is facing great and challenging responsibility. The fashion industry needs a system of rules able to assess the sustainability of products, which is transparent and easily interpreted by consumers, identifying and enhancing virtuous practices. There are still complex and fragmented value chains that make it extremely difficult for brands and manufacturers to know the history of their products, to identify exactly where the risks lie, and to respond to the growing demand from consumers and civil society for responsible and sustainable production practices in the fashion industry.

Keywords: fashion design, fashion system, sustainability, communication, complexity

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Authors: Fang Li, Jiazhao Wang, Jianmin Ma

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The practical application of Li-S batteries is hampered due to poor cycling stability caused by electrolyte-dissolved lithium polysulfides. Dual functionalities such as strong chemical adsorption stability and high conductivity are highly desired for an ideal host material for a sulfur-based cathode. Polypyrrole (PPy), as a conductive polymer, was widely studied as matrixes for sulfur cathode due to its high conductivity and strong chemical interaction with soluble polysulfides. Thus, a novel cathode structure consisting of a free-standing sulfur-polypyrrole cathode and a polypyrrole coated separator was designed for flexible Li-S batteries. The PPy materials show strong interaction with dissoluble polysulfides, which could suppress the shuttle effect and improve the cycling stability. In addition, the synthesized PPy film with a rough surface acts as a current collector, which improves the adhesion of sulfur materials and restrain the volume expansion, enhancing the structural stability during the cycling process. For further enhancing the cycling stability, a PPy coated separator was also applied, which could make polysulfides into the cathode side to alleviate the shuttle effect. Moreover, the PPy layer coated on commercial separator is much lighter than other reported interlayers. A soft-packaged flexible Li-S battery has been designed and fabricated for testing the practical application of the designed cathode and separator, which could power a device consisting of 24 light-emitting diode (LED) lights. Moreover, the soft-packaged flexible battery can still show relatively stable cycling performance after repeated bending, indicating the potential application in flexible batteries. A novel vapor phase deposition method was also applied to prepare uniform polypyrrole layer coated sulfur/graphene aerogel composite. The polypyrrole layer simultaneously acts as host and adsorbent for efficient suppression of polysulfides dissolution through strong chemical interaction. The density functional theory (DFT) calculations reveal that the polypyrrole could trap lithium polysulfides through stronger bonding energy. In addition, the deflation of sulfur/graphene hydrogel during the vapor phase deposition process enhances the contact of sulfur with matrixes, resulting in high sulfur utilization and good rate capability. As a result, the synthesized polypyrrole coated sulfur/graphene aerogel composite delivers a specific discharge capacity of 1167 mAh g⁻¹ and 409.1 mAh g⁻¹ at 0.2 C and 5 C respectively. The capacity can maintain at 698 mAh g⁻¹ at 0.5 C after 500 cycles, showing an ultra-slow decay rate of 0.03% per cycle.

Keywords: polypyrrole, strong chemical interaction, long-term stability, Li-S batteries

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Authors: Mohammad Emamjome Kashan, Alan S. Fung

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In Canada, more than 32% of the total energy demand is related to the building sector. Therefore, there is a great opportunity for Greenhouse Gases (GHG) reduction by integrating solar collectors to provide building heating load and domestic hot water (DHW). Despite the cold winter weather, Canada has a good number of sunny and clear days that can be considered for diurnal solar thermal energy storage. Due to the energy mismatch between building heating load and solar irradiation availability, relatively big storage tanks are usually needed to store solar thermal energy during the daytime and then use it at night. On the other hand, water tanks occupy huge space, especially in big cities, space is relatively expensive. This project investigates the possibility of using a specific building construction material (ICF – Insulated Concrete Form) as diurnal solar thermal energy storage that is integrated with a heat pump and microchannel solar thermal collector (MCST). Not much literature has studied the application of building pre-existing walls as active solar thermal energy storage as a feasible and industrialized solution for the solar thermal mismatch. By using ICF walls that are integrated into the building envelope, instead of big storage tanks, excess solar energy can be stored in the concrete of the ICF wall that consists of EPS insulation layers on both sides to store the thermal energy. In this study, two solar-based systems are designed and simulated inTransient Systems Simulation Program(TRNSYS)to compare ICF wall thermal storage benefits over the system without ICF walls. In this study, the heating load and DHW of a Canadian single-family house located in London, Ontario, are provided by solar-based systems. The proposed system integrates the MCST collector, a water-to-water HP, a preheat tank, the main tank, fan coils (to deliver the building heating load), and ICF walls. During the day, excess solar energy is stored in the ICF walls (charging cycle). Thermal energy can be restored from the ICF walls when the preheat tank temperature drops below the ICF wall (discharging process) to increase the COP of the heat pump. The evaporator of the heat pump is taking is coupled with the preheat tank. The provided warm water by the heat pump is stored in the second tank. Fan coil units are in contact with the tank to provide a building heating load. DHW is also delivered is provided from the main tank. It is investigated that the system with ICF walls with an average solar fraction of 82%- 88% can cover the whole heating demand+DHW of nine months and has a 10-15% higher average solar fraction than the system without ICF walls. Sensitivity analysis for different parameters influencing the solar fraction is discussed in detail.

Keywords: net-zero building, renewable energy, solar thermal storage, microchannel solar thermal collector

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Authors: Ana-María Gómez-Carvajal, Hernando Santamaría-García, Mateo Bernal, Mario Valderrama, Daniela Lizarazo, Juliana Restrepo, María Fernanda Barreto, Angélica Parra, Paula Torres, Diana Matallana, Jaime Silva, José Santamaría-García, Sandra Baez

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Higher levels of oxytocin are associated with better performance on social cognition tasks. However, higher levels of oxytocin have also been associated with increased levels of envy and schadenfreude. Considering these antecedents, this study aims to explore social emotions (i.e., envy and schadenfreude) and other components of social cognition (i.e. ToM and empathy), in women in the puerperal period and their respective partners, compared to a control group of men and women without children or partners. Control women should be in the luteal phase of the menstrual cycle or taking oral contraceptives as they allow oxytocin levels to remain stable. We selected this population since increased levels of oxytocin are present in both mothers and fathers of newborn babies. Both groups were matched by age, sex, and education level. Twenty-two parents of newborns (11 women, 11 men) and 15 controls (8 women, 7 men) performed an experimental task designed to trigger schadenfreude and envy. In this task, each participant was shown a real-life photograph and a description of two target characters matched in age and gender with the participant. The task comprised two experimental blocks. In the first block, participants read 15 sentences describing fortunate events involving either character. After reading each sentence, participants rated the event in terms of how much envy they felt for the character (1=no envy, 9=extreme envy). In the second block, participants read and reported the intensity of their pleasure (schadenfreude, 1=no pleasure, 9=extreme pleasure) in response to 15 unfortunate events happening to the characters. Five neutral events were included in each block. Moreover, participants were assessed with ToM and empathy tests. Potential confounding variables such as general cognitive functioning, stress levels, hours of sleep and depression symptoms were also measured. Results showed that parents of newborns showed increased levels of envy and schadenfreude. These effects are not explained by any confounding factor. Moreover, no significant differences were found in ToM or empathy tests. Our results offer unprecedented evidence of specific differences in envy and schadenfreude levels in parents of newborns. Our findings support previous studies showing a negative relationship between oxytocin levels and negative social emotions. Further studies should assess the direct relationship between oxytocin levels in parents of newborns and the performance in social emotions tasks.

Keywords: envy, empathy, oxytocin, schadenfreude, social emotions, theory of mind

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Authors: Vanessa Bennemann, Gabriela Laste, Márcia Inês Goettert

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The gestational period is a phase in which the pregnant woman undergoes constant physiological and hormonal changes, which are part of the woman’s biological cycle, the development of the fetus, childbirth, and lactation. These are factors of response to the immunological adaptation of the human reproductive process that is directly related to the pregnancy’s well-being and development. Although most pregnancies occur without complications, about 15% of pregnant women will develop potentially fatal complications, implying maternal and fetal risk. Therefore, requiring specialized care for high-risk pregnant women (HRPW) with obstetric interventions for the survival of the mother and/or fetus. Among the risk factors that characterize HRPW are the women's age, gestational diabetes mellitus (GDM), autoimmune diseases, infectious diseases such as syphilis and HIV, hypertension (SAH), preeclampsia, eclampsia, HELLP syndrome, uterine contraction abnormalities, and premature placental detachment (PPD), thyroid disorders, among others. Thus, pregnancy has an impact on the thyroid gland causing changes in the functioning of the mother's thyroid gland, altering the thyroid hormone (TH) profiles and production as pregnancy progresses. Considering, throughout the gestational period, the interpretation of the results of the tests to evaluate the thyroid functioning depends on the stage in which the pregnancy is. Thyroid disorders are directly related to adverse obstetric outcomes and in child development. Therefore, the adequate release of TH is important for a pregnancy without complications and optimal fetal growth and development. Objective: Investigate the physiological effects caused by thyroid disorders in the gestational period. Methods: A search for articles indexed in PubMed, Scielo, and MDPI databases, was performed using the term “AND”, with the descriptors: Pregnancy, Thyroid. With several combinations that included: Melatonin, Thyroidopathy, Inflammatory processes, Cytokines, Anti-inflammatory, Antioxidant, High-risk pregnancy. Subsequently, the screening was performed through the analysis of titles and/or abstracts. The criteria were: including clinical studies in general, randomized or not, in the period of 10 years prior to the research, in the English literature; excluded: experimental studies, case reports, research in the development phase. Results: In the preliminary results, a total of studies (n=183) were found, (n=57) excluded, such as studies of cancer, diabetes, obesity, and skin diseases. Conclusion: To date, it has been identified that thyroid diseases can impair the fetus’s brain development. Further research is suggested on this matter to identify new substances that may have a potential therapeutic effect to aid the gestational period with thyroid diseases.

Keywords: pregnancy, thyroid, melatonin, high-risk pregnancy

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Authors: Himanshu Kumar Gupta

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The Jaisalmer Basin is one of the parts of the Rajasthan basin in northwestern India. The presence of five major unconformities/hiatuses of varying span i.e. at the top of Archean basement, Cambrian, Jurassic, Cretaceous, and Eocene have created the foundation for constructing a sequence stratigraphic framework. Based on basin formative tectonic events and their impact on sedimentation processes three first-order sequences have been identified in Rajasthan Basin. These are Proterozoic-Early Cambrian rift sequence, Permian to Middle-Late Eocene shelf sequence and Pleistocene - Recent sequence related to Himalayan Orogeny. The Permian to Middle Eocene I order sequence is further subdivided into three-second order sequences i.e. Permian to Late Jurassic II order sequence, Early to Late Cretaceous II order sequence and Paleocene to Middle-Late Eocene II order sequence. In this study, Late Jurassic to Early Cretaceous sequence was identified and log-based interpretation of smaller order T-R cycles have been carried out. A log profile from eastern margin to western margin (up to Shahgarh depression) has been taken. The depositional environment penetrated by the wells interpreted from log signatures gave three major facies association. The blocky and coarsening upward (funnel shape), the blocky and fining upward (bell shape) and the erratic (zig-zag) facies representing distributary mouth bar, distributary channel and marine mud facies respectively. Late Jurassic Formation (Baisakhi-Bhadasar) and Early Cretaceous Formation (Pariwar) shows a lesser number of T-R cycles in shallower and higher number of T-R cycles in deeper bathymetry. Shallowest well has 3 T-R cycles in Baisakhi-Bhadasar and 2 T-R cycles in Pariwar, whereas deeper well has 4 T-R cycles in Baisakhi-Bhadasar and 8 T-R cycles in Pariwar Formation. The Maximum Flooding surfaces observed from the stratigraphy analysis indicate major shale break (high shale content). The study area is dominated by the alternation of shale and sand lithologies, which occurs in an approximate ratio of 70:30. A seismo-geological cross section has been prepared to understand the stratigraphic thickness variation and structural disposition of the strata. The formations are quite thick to the west, the thickness of which reduces as we traverse towards the east. The folded and the faulted strata indicated the compressional tectonics followed by the extensional tectonics. Our interpretation is supported with seismic up to second order sequence indicates - Late Jurassic sequence is a Highstand Systems Tract (Baisakhi - Bhadasar formations), and the Early Cretaceous sequence is Regressive to Lowstand System Tract (Pariwar Formation).

Keywords: Jaisalmer Basin, sequence stratigraphy, system tract, T-R cycle

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Authors: Adonis Menezes, J. C. Passos

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The current panorama of technology in heat transfer and the scarcity of information about the convective boiling of CO₂ and hydrocarbon in small diameter channels motivated the development of this work. Among non-halogenated refrigerants, CO₂/ R744 has distinct thermodynamic properties compared to other fluids. The R744 presents significant differences in operating pressures and temperatures, operating at higher values compared to other refrigerants, and this represents a challenge for the design of new evaporators, as the original systems must normally be resized to meet the specific characteristics of the R744, which creates the need for a new design and optimization criteria. To carry out the convective boiling tests of CO₂, an experimental apparatus capable of storing (m= 10kg) of saturated CO₂ at (T = -30 ° C) in an accumulator tank was used, later this fluid was pumped using a positive displacement pump with three pistons, and the outlet pressure was controlled and could reach up to (P = 110bar). This high-pressure saturated fluid passed through a Coriolis type flow meter, and the mass velocities varied between (G = 20 kg/m².s) up to (G = 1000 kg/m².s). After that, the fluid was sent to the first test section of circular cross-section in diameter (D = 4.57mm), where the inlet and outlet temperatures and pressures, were controlled and the heating was promoted by the Joule effect using a source of direct current with a maximum heat flow of (q = 100 kW/m²). The second test section used a cross-section with multi-channels (seven parallel channels) with a square cross-section of (D = 2mm) each; this second test section has also control of temperature and pressure at the inlet and outlet as well as for heating a direct current source was used, with a maximum heat flow of (q = 20 kW/m²). The fluid in a biphasic situation was directed to a parallel plate heat exchanger so that it returns to the liquid state, thus being able to return to the accumulator tank, continuing the cycle. The multi-channel test section has a viewing section; a high-speed CMOS camera was used for image acquisition, where it was possible to view the flow patterns. The experiments carried out and presented in this report were conducted in a rigorous manner, enabling the development of a database on the convective boiling of the R744 in macro and micro channels. The analysis prioritized the processes from the beginning of the convective boiling until the drying of the wall in a subcritical regime. The R744 resurfaces as an excellent alternative to chlorofluorocarbon refrigerants due to its negligible ODP (Ozone Depletion Potential) and GWP (Global Warming Potential) rates, among other advantages. The results found in the experimental tests were very promising for the use of CO₂ in micro-channels in convective boiling and served as a basis for determining the flow pattern map and correlation for determining the heat transfer coefficient in the convective boiling of CO₂.

Keywords: convective boiling, CO₂/R744, macro-channels, micro-channels

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Authors: Sofia Maria Poulimenou, Ioannis Deliyannis, Elisavet Filippidou, Stamatella Laboura

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Smart technologies are being actively used to improve the experience of travel and promote or demote a destination’s reputation via a wide variety of social media applications and platforms. This paper conceptualises the design and deployment of smart management apps to promote culture, sustainability and accessibility within two destinations in Greece that represent the extremes of visiting scale. One is the densely visited Corfu, which is a UNESCO’s heritage site. The problems caused by the lack of organisation of the visiting experience and infrastructures affect all parties interacting within the site: visitors, citizens, public and private sector. Second is Kilkis, a low tourism destination with high seasonality and mostly inbound tourism. Here the issue faced is that traditional approaches to inform and motivate locals and visitors to explore and taste of the culture have not flourished. The problem is apprehended via the design and development of two systems named “Hologrammatic Corfu” for Corfu old town and “BRENDA” for the area of Kilkis. Although each system is designed independently, featuring different solutions to the problems, both approaches have been designed by the same team and a novel gaming and gamification methodology. The “Hologramatic Corfu” application has been designed, for the exploration of the site covering user requirments before, during and after the trip, with the use of transmedia content such as photos, 360-degree videos, augmented reality and hologrammatic videos. Also, a statistical analysis of travellers’ visits to specific points of interest is actively utilized enabling visitors to dynamically re-rooted during their visit, safeguarding sustainability and accessibility and inclusivity along the entire tourism cycle. “BRENDA” is designed specifically to promote gastronomic and historical tourism. This serious game implements and combines gaming and gamification elements in order to connect local businesses with cultural points of interest. As the environment of the project has a strong touristic orientation, “BRENDA” supports food-related gamified processes and historical games involving active participation of both local communities (content providers) and visitors (players) which are more likely to be successfully performed in the informal environment of travelling and promote sustainable tourism experiences. Finally, the paper presents the ability to re-use existing gaming components within new areas of interest via minimal adaptation and the use of transmedia aspects that enables destinations to be rebranded into smart destinations.

Keywords: smart tourism, gamification, user experience, transmedia content

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Authors: Boriana Karamanova, Svetlana Veleva, Luybomir Soserov, Ana Arenillas, Francesco Lufrano, Antonia Stoyanova

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Supercapacitors have received a lot of research attention and are promising energy storage devices due to their high power and long cycle life. In order to developed an advanced device with significant capacity for storing charge and cheap carbon materials, efforts must focus not only on improving synthesis by controlling the morphology and pore size but also on improving electrode-electrolyte compatibility of the resulting systems. The present study examines the relationship between the surface chemistry of two activated carbon xerogels, the electrolyte type, and the electrochemical properties of supercapacitors. Activated carbon xerogels were prepared by varying the initial pH of the resorcinol-formaldehyde aqueous solution. The materials produced are physicochemical characterized by DTA/TGA, porous characterization, and SEM analysis. The carbon xerogel based electrodes were prepared by spreading over glass plate a slurry containing the carbon gel, graphite, and poly vinylidene difluoride (PVDF) binder. The layer formed was dried consecutively at different temperatures and then detached by water. After, the layer was dried again to improve its mechanical stability. The developed electrode materials and the Aquivion® E87-05S membrane (Solvay Specialty Polymers), socked in Na2SO4 as a polymer electrolyte, were used to assembly the solid-state supercapacitor. Symmetric supercapacitor cells composed by same electrodes and 1 M KOH electrolytes are also assembled and tested for comparison. The supercapacitor performances are verified by different electrochemical methods - cyclic voltammetry, galvanostatic charge/discharge measurements, electrochemical impedance spectroscopy, and long-term durability tests in neutral and alkaline electrolytes. Specific capacitances, energy, and power density, energy efficiencies, and durability were compared into studied supercapacitors. Ex-situ physicochemical analyses on the synthesized materials have also been performed, which provide information about chemical and structural changes in the electrode morphology during charge / discharge durability tests. They are discussed on the basis of electrode-electrolyte interaction. The obtained correlations could be of significance in order to design sustainable solid-state supercapacitors with high power and energy density. Acknowledgement: This research is funded by the Ministry of Education and Science of Bulgaria under the National Program "European Scientific Networks" (Agreement D01-286 / 07.10.2020, D01-78/30.03.2021). Authors gratefully acknowledge.

Keywords: carbon xerogel, electrochemical tests, neutral and alkaline electrolytes, supercapacitors

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Authors: Khalid Omari, Rene Chenier, Enrique Blondel, Ryan Ahola

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Northern Canadian coasts have vulnerable and very dynamic intertidal zones with very high tides occurring in several areas. The impact of climate change presents challenges not only for maintaining this biodiversity but also for navigation safety adaptation due to the high sediment mobility in these coastal areas. Thus, frequent mapping of shorelines and intertidal changes is of high importance. To help in quantifying the changes in these fragile ecosystems, remote sensing provides practical monitoring tools at local and regional scales. Traditional methods based on high-resolution optical sensors are often used to map intertidal areas by benefiting of the spectral response contrast of intertidal classes in visible, near and mid-infrared bands. Tidal areas are highly reflective in visible bands mainly because of the presence of fine sand deposits. However, getting a cloud-free optical data that coincide with low tides in intertidal zones in northern regions is very difficult. Alternatively, the all-weather capability and daylight-independence of the microwave remote sensing using synthetic aperture radar (SAR) can offer valuable geophysical parameters with a high frequency revisit over intertidal zones. Multi-polarization SAR parameters have been used successfully in mapping intertidal zones using incoherence target decomposition. Moreover, the crustal displacements caused by ocean tide loading may reach several centimeters that can be detected and quantified across differential interferometric synthetic aperture radar (DInSAR). Soil moisture change has a significant impact on both the coherence and the backscatter. For instance, increases in the backscatter intensity associated with low coherence is an indicator for abrupt surface changes. In this research, we present primary results obtained following our investigation of the potential of the fully polarimetric Radarsat-2 data for mapping an inter-tidal zone located on Tasiujaq on the south-west shore of Ungava Bay, Quebec. Using the repeat pass cycle of Radarsat-2, multiple seasonal fine quad (FQ14W) images are acquired over the site between 2016 and 2018. Only 8 images corresponding to low tide conditions are selected and used to build an interferometric stack of data. The observed displacements along the line of sight generated using HH and VV polarization are compared with the changes noticed using the Freeman Durden polarimetric decomposition and Touzi degree of polarization extrema. Results show the consistency of both approaches in their ability to monitor the changes in intertidal zones.

Keywords: SAR, degree of polarization, DInSAR, Freeman-Durden, polarimetry, Radarsat-2

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Authors: Christopher Latella, Ashlee M. Hendy, Dan Vander Westhuizen, Wei-Peng Teo

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Introduction: Neural adaptations following resistance training interventions have been widely investigated, however the evidence regarding the mechanisms of early adaptation are less clear. Understanding neural responses from an acute resistance training session is pivotal in the prescription of frequency, intensity and volume in applied strength and conditioning practice. Therefore the primary aim of this study was to investigate the time course of neurophysiological mechanisms post training against current super compensation theory, and secondly, to examine whether these responses reflect neural adaptations observed with resistance training interventions. Methods: Participants (N=14) completed a randomised, counterbalanced crossover study comparing; control, strength and hypertrophy conditions. The strength condition involved 3 x 5RM leg extensions with 3min recovery, while the hypertrophy condition involved 3 x 12 RM with 60s recovery. Transcranial magnetic stimulation (TMS) and peripheral nerve stimulation were used to measure excitability of the central and peripheral neural pathways, and maximal voluntary contraction (MVC) to quantify strength changes. Measures were taken pre, immediately post, 10, 20 and 30 mins and 1, 2, 6, 24, 48, 72 and 96 hrs following training. Results: Significant decreases were observed at post, 10, 20, 30 min, 1 and 2 hrs for both training groups compared to control group for force, (p <.05), maximal compound wave; (p < .005), silent period; (p < .05). A significant increase in corticospinal excitability; (p < .005) was observed for both groups. Corticospinal excitability between strength and hypertrophy groups was near significance, with a large effect (η2= .202). All measures returned to baseline within 6 hrs post training. Discussion: Neurophysiological mechanisms appear to be significantly altered in the period 2 hrs post training, returning to homeostasis by 6 hrs. The evidence suggests that the time course of neural recovery post resistance training occurs 18-40 hours shorter than previous super compensation models. Strength and hypertrophy protocols showed similar response profiles with current findings suggesting greater post training corticospinal drive from hypertrophy training, despite previous evidence that strength training requires greater neural input. The increase in corticospinal drive and decrease inl inhibition appear to be a compensatory mechanism for decreases in peripheral nerve excitability and maximal voluntary force output. The changes in corticospinal excitability and inhibition are akin to adaptive processes observed with training interventions of 4 wks or longer. It appears that the 2 hr recovery period post training is the most influential for priming further neural adaptations with resistance training. Secondly, the frequency of prescribed resistance sessions can be scheduled closer than previous super compensation theory for optimal strength gains.

Keywords: neural responses, resistance training, super compensation, transcranial magnetic stimulation

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Authors: Patrícia Severino, Luciana Nalone, Daniele Martins, Marco Chaud, Classius Ferreira, Cristiane Bani, Ricardo Albuquerque

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Hydrogels produced with polymers have been used in the development of dressings for wound treatment and tissue revitalization. Our study on polymer nanocomposites containing silver nanoparticles shows antimicrobial activity and applications in wound healing. The effects are linked with the slow oxidation and Ag⁺ liberation to the biological environment. Furthermore, bacterial cell membrane penetration and metabolic disruption through cell cycle disarrangement also contribute to microbial cell death. The silver antimicrobial activity has been known for many years, and previous reports show that low silver concentrations are safe for human use. This work aims to develop a hydrogel using natural polymers (sodium alginate and gelatin) combined with silver nanoparticles for wound healing and with antimicrobial properties in cutaneous lesions. The hydrogel development utilized different sodium alginate and gelatin proportions (20:80, 50:50 and 80:20). The silver nanoparticles incorporation was evaluated at the concentrations of 1.0, 2.0 and 4.0 mM. The physico-chemical properties of the formulation were evaluated using ultraviolet-visible (UV-Vis) absorption spectroscopy, Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric (TG) analysis. The morphological characterization was made using transmission electron microscopy (TEM). Human fibroblast (L2929) viability assay was performed with a minimum inhibitory concentration (MIC) assessment as well as an in vivo cicatrizant test. The results suggested that sodium alginate and gelatin in the (80:20) proportion with 4 mM of AgNO₃ in the (UV-Vis) exhibited a better hydrogel formulation. The nanoparticle absorption spectra of this analysis showed a maximum band around 430 - 450 nm, which suggests a spheroidal form. The TG curve exhibited two weight loss events. DSC indicated one endothermic peak at 230-250 °C, due to sample fusion. The polymers acted as stabilizers of a nanoparticle, defining their size and shape. Human fibroblast viability assay L929 gave 105 % cell viability with a negative control, while gelatin presented 96% viability, alginate: gelatin (80:20) 96.66 %, and alginate 100.33 % viability. The sodium alginate:gelatin (80:20) exhibited significant antimicrobial activity, with minimal bacterial growth at a ratio of 1.06 mg.mL⁻¹ in Pseudomonas aeruginosa and 0.53 mg.mL⁻¹ in Staphylococcus aureus. The in vivo results showed a significant reduction in wound surface area. On the seventh day, the hydrogel-nanoparticle formulation reduced the total area of injury by 81.14 %, while control reached a 45.66 % reduction. The results suggest that silver-hydrogel nanoformulation exhibits potential for wound dressing therapeutics.

Keywords: nanocomposite, wound healing, hydrogel, silver nanoparticle

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Authors: H. Mayton, X. Yan, A. G. Taylor

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Infested tomato seeds were used to investigate the influence of Xanthomonas euvesicatoria on germination and seed to seedling transmission in a controlled environment and greenhouse assays in an effort to develop effective seed treatments and characterize seed borne transmission of bacterial leaf spot of tomato. Bacterial leaf spot of tomato, caused by four distinct Xanthomonas species, X. euvesicatoria, X. gardneri, X. perforans, and X. vesicatoria, is a serious disease worldwide. In the United States, disease prevention is expensive for commercial growers in warm, humid regions of the country, and crop losses can be devastating. In this study, four different infested tomato seed lots were extracted from tomato fruits infected with bacterial leaf spot from a field in New York State in 2017 that had been inoculated with X. euvesicatoria. In addition, vacuum infiltration at 61 kilopascals for 1, 5, 10, and 15 minutes and seed soaking for 5, 10, 15, and 30 minutes with different bacterial concentrations were used to artificially infest seed in the laboratory. For controlled environment assays, infested tomato seeds from the field and laboratory were placed othe n moistened blue blotter in square plastic boxes (10 cm x 10 cm) and incubated at 20/30 ˚C with an 8/16 hour light cycle, respectively. Infested tomato seeds from the field and laboratory were also planted in small plastic trays in soil (peat-lite medium) and placed in the greenhouse with 24/18 ˚C day and night temperatures, respectively, with a 14-hour photoperiod. Seed germination was assessed after eight days in the laboratory and 14 days in the greenhouse. Polymerase chain reaction (PCR) using the hrpB7 primers (RST65 [5’- GTCGTCGTTACGGCAAGGTGGTG-3’] and RST69 [5’-TCGCCCAGCGTCATCAGGCCATC-3’]) was performed to confirm presence or absence of the bacterial pathogen in seed lots collected from the field and in germinating seedlings in all experiments. For infested seed lots from the field, germination was lowest (84%) in the seed lot with the highest level of bacterial infestation (55%) and ranged from 84-98%. No adverse effect on germination was observed from artificially infested seeds for any bacterial concentration and method of infiltration when compared to a non-infested control. Germination in laboratory assays for artificially infested seeds ranged from 82-100%. In controlled environment assays, 2.5 % were PCR positive for the pathogen, and in the greenhouse assays, no infected seedlings were detected. From these experiments, X. euvesicatoria does not appear to adversely influence germination. The lowest rate of germination from field collected seed may be due to contamination with multiple pathogens and saprophytic organisms as no effect of artificial bacterial seed infestation in the laboratory on germination was observed. No evidence of systemic movement from seed to seedling was observed in the greenhouse assays; however, in the controlled environment assays, some seedlings were PCR positive. Additional experiments are underway with green fluorescent protein-expressing isolates to further characterize seed to seedling transmission of the bacterial leaf spot pathogen in tomato.

Keywords: bacterial leaf spot, seed germination, tomato, Xanthomonas euvesicatoria

Procedia PDF Downloads 114

Authors: Katie Dolaghan, Christina Tran, Kim Hamilton, Amanda Beresford, Vicky Adams, Jamie Toole, John Marley

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During the Covid 19 pandemic routine outpatient appointments were not possible face to face. That resulted in many branches of healthcare starting virtual clinics. These clinics have continued following the return to face to face patient appointments. With these new types of clinic it is important to ensure that a high standard of patient care is maintained. In order to improve patient and clinician experience of the telephone clinics a quality improvement project was carried out to ensure the patient and clinician experience of these clinics was enhanced whilst remaining a safe, effective and an efficient use of resources. The project began by developing a process map for the consultation process and agreed on the design of a driver diagram and tests of change. In plan do study act (PDSA) cycle1 a single consultant completed an online survey after every patient encounter over a 5 week period. Baseline patient responses were collected using a follow-up telephone survey for each patient. Piloting led to several iterations of both survey designs. Salient results of PDSA1 included; patients not receiving appointment letters, patients feeling more anxious about a virtual appointment and many would prefer a face to face appointment. The initial clinician data showed a positive response with a provisional diagnosis being reached in 96.4% of encounters. PDSA cycle 2 included provision of a patient information sheet and information leaflets relevant to the patients’ conditions were developed and sent following new patient telephone clinics with follow-up survey analysis as before to monitor for signals of change. We also introduced the ability for patients to send an images of their lesion prior to the consultation. Following the changes implemented we noted an improvement in patient satisfaction and, in fact, many patients preferring virtual clinics as it lead to less disruption of their working lives. The extra reading material both before and after the appointments eased patients’ anxiety around virtual clinics and helped them to prepare for their appointment. Following the patient feedback virtual clinics are now used for review patients as well, with all four consultants within the department continuing to utilise virtual clinics. During this presentation the progression of these clinics and the reasons that these clinics are still operating following the return to face to face appointments will be explored. The lessons that have been gained using a QI approach have helped to deliver an optimal service that is valid and reliable as well as being safe, effective and efficient for the patient along with helping reduce the pressures from ever increasing waiting lists. In summary our work in improving the quality of virtual clinics has resulted in improved patient satisfaction along with reduced pressures on the facilities of the health trust.

Keywords: clinic, satisfaction, telephone, virtual

Procedia PDF Downloads 39

Authors: Abubakar Rashid, Muhammad Saad, Faheem Ahmed

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This paper provides a comprehensive study pertaining to diagnosis of intermittent high vibrations on an industrial gas turbine using detailed vibrations analysis, followed by its rectification. Engro Polymer & Chemicals Limited, a Chlor-Vinyl complex located in Pakistan has a captive combined cycle power plant having two 28 MW gas turbines (make Hitachi) & one 15 MW steam turbine. In 2018, the organization faced an issue of high vibrations on one of the gas turbines. These high vibration peaks appeared intermittently on both compressor’s drive end (DE) & turbine’s non-drive end (NDE) bearing. The amplitude of high vibration peaks was between 150-170% on the DE bearing & 200-300% on the NDE bearing from baseline values. In one of these episodes, the gas turbine got tripped on “High Vibrations Trip” logic actuated at 155µm. Limited instrumentation is available on the machine, which is monitored with GE Bently Nevada 3300 system having two proximity probes installed at Turbine NDE, Compressor DE &at Generator DE & NDE bearings. Machine’s transient ramp-up & steady state data was collected using ADRE SXP & DSPI 408. Since only 01 key phasor is installed at Turbine high speed shaft, a derived drive key phasor was configured in ADRE to obtain low speed shaft rpm required for data analysis. By analyzing the Bode plots, Shaft center line plot, Polar plot & orbit plots; rubbing was evident on Turbine’s NDE along with increased bearing clearance of Turbine’s NDE radial bearing. The subject bearing was then inspected & heavy deposition of carbonized coke was found on the labyrinth seals of bearing housing with clear rubbing marks on shaft & housing covering at 20-25 degrees on the inner radius of labyrinth seals. The collected coke sample was tested in laboratory & found to be the residue of lube oil in the bearing housing. After detailed inspection & cleaning of shaft journal area & bearing housing, new radial bearing was installed. Before assembling the bearing housing, cleaning of bearing cooling & sealing air lines was also carried out as inadequate flow of cooling & sealing air can accelerate coke formation in bearing housing. The machine was then taken back online & data was collected again using ADRE SXP & DSPI 408 for health analysis. The vibrations were found in acceptable zone as per ISO standard 7919-3 while all other parameters were also within vendor defined range. As a learning from subject case, revised operating & maintenance regime has also been proposed to enhance machine’s reliability.

Keywords: ADRE, bearing, gas turbine, GE Bently Nevada, Hitachi, vibration

Procedia PDF Downloads 116

Authors: Magdalena Grudzińska

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Passive systems allow solar radiation to be converted into thermal energy thanks to appropriate building construction. Greenhouse systems are particularly worth attention, due to the low costs of their realization and strong architectural appeal. The paper discusses the energy effects of using passive greenhouse systems, such as glazed balconies, in an example residential building. The research was carried out for five localities in Poland, belonging to climatic zones different in terms of external air temperature and insolation: Koszalin, Poznań, Lublin, Białystok and Zakopane The analysed apartment had a floor area of approximately 74 m² Three thermal zones were distinguished in the flat - the balcony, the room adjacent to it, and the remaining space, for which various internal conditions were defined. Calculations of the energy demand were made using the dynamic simulation program, based on the control volume method. The climatic data were represented by Typical Meteorological Years, prepared on the basis of source data collected from 1971 to 2000. In each locality, the introduction of a passive greenhouse system led to a lower demand for heating in the apartment, and the shortening of the heating season. The smallest effectiveness of passive solar energy systems was noted in Białystok. Demand for heating was reduced there by 14.5% and the heating season remained the longest, due to low temperatures of external air and small sums of solar radiation intensity. In Zakopane, energy savings came to 21% and the heating season was reduced to 107 days, thanks to the greatest insolation during winter. The introduction of greenhouse systems caused an increase in cooling demand in the warmer part of the year, but total energy demand declined in each of the discussed places. However, potential energy savings are smaller if the building's annual life cycle is taken into consideration, and amount from 5.6% up to 14%. Koszalin and Zakopane are localities in which the greenhouse system allows the best energy results to be achieved. It should be emphasized that favourable conditions for introducing greenhouse systems are connected with different climatic conditions. In the seaside area (Koszalin) they result from high temperatures in the heating season and the smallest insolation in the summer period, while in the mountainous area (Zakopane) they result from high insolation in the winter and low temperatures in the summer. In the region of middle and middle-eastern Poland active systems (such as solar energy collectors or photovoltaic panels) could be more beneficial, due to high insolation during summer. It is assessed that passive systems do not eliminate the need for traditional heating in Poland. They can, however, substantially contribute to lower use of non-renewable fuels and the shortening of the heating season. The calculations showed diversification in the effectiveness of greenhouse systems resulting from climatic conditions, and allowed to identify areas which are the most suitable for the passive use of solar radiation.

Keywords: solar energy, passive greenhouse systems, glazed balconies, climatic conditions

Procedia PDF Downloads 346

Authors: Walter Vera-Ortega, Idoia Busnadiego, Sam J. Wilson

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Introduction: Human Immunodeficiency Virus type 1 (HIV-1) is responsible for the acquired immunodeficiency syndrome (AIDS), a leading cause of death worldwide infecting millions of people each year. Despite intensive research in vaccine development, therapies against HIV-1 infection are not curative, and the huge genetic variability of HIV-1 challenges to drug development. Current animal models for HIV-1 research present important limitations, impairing the progress of in vivo approaches. Macaques require a CD8+ depletion to progress to AIDS, and the maintenance cost is high. Mice are a cheaper alternative but need to be 'humanized,' and breeding is not possible. The development of an HIV-1 clone able to replicate in mice is a challenging proposal. The lack of human co-factors in mice impedes the function of the HIV-1 accessory proteins, Tat and Rev, hampering HIV-1 replication. However, Tat and Rev function can be replaced by constitutive/chimeric promoters, codon-optimized proteins and the constitutive transport element (CTE), generating a novel HIV-1 clone able to replicate in mice without disrupting the amino acid sequence of the virus. By minimally manipulating the genomic 'identity' of the virus, we propose the generation of an HIV-1 clone able to replicate in mice to assist in antiviral drug development. Methods: i) Plasmid construction: The chimeric promoters and CTE copies were cloned by PCR using lentiviral vectors as templates (pCGSW and pSIV-MPCG). Tat mutants were generated from replication competent HIV-1 plasmids (NHG and NL4-3). ii) Infectivity assays: Retroviral vectors were generated by transfection of human 293T cells and murine NIH 3T3 cells. Virus titre was determined by flow cytometry measuring GFP expression. Human B-cells (AA-2) and Hela cells (TZMbl) were used for infectivity assays. iii) Protein analysis: Tat protein expression was determined by TZMbl assay and HIV-1 capsid by western blot. Results: We have determined that NIH 3T3 cells are able to generate HIV-1 particles. However, they are not infectious, and further analysis needs to be performed. Codon-optimized HIV-1 constructs are efficiently made in 293T cells in a Tat and Rev independent manner and capable of packaging a competent genome in trans. CSGW is capable of generating infectious particles in the absence of Tat and Rev in human cells when 4 copies of the CTE are placed preceding the 3’LTR. HIV-1 Tat mutant clones encoding different promoters are functional during the first cycle of replication when Tat is added in trans. Conclusion: Our findings suggest that the development of an HIV-1 Tat-Rev independent clone is challenging but achievable aim. However, further investigations need to be developed prior presenting our HIV-1 clone as a candidate model for research.

Keywords: codon-optimized, constitutive transport element, HIV-1, long terminal repeats, research model

Procedia PDF Downloads 280

Authors: Aderonke Olaitan Adesina

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Background: The paradigm shift to knowledge, as the key to organizational innovation and competitive advantage, has made the management of knowledge resources in organizations a mandate. A key component of the knowledge management (KM) cycle is knowledge creation, which is researched to be the result of the interaction between explicit and tacit knowledge. An effective knowledge creation process requires the use of the right model. The SECI (Socialisation, Externalisation, Combination, and Internalisation) model, proposed in 1995, is attested to be a preferred model of choice for knowledge creation activities. The model has, however, been criticized by researchers, who raise their concern, especially about its sequential nature. Therefore, this paper reviews extant literature on the practical application of each mode of the SECI model, from 1995 to date, with a view to ascertaining the relevance in modern-day KM practice. The study will establish the trends of use, with regards to the location and industry of use, and the interconnectedness of the modes. The main research question is, for organizational knowledge creation activities, is the SECI model indeed linear and sequential? In other words, does the model need to be reviewed in today’s KM practice? The review will generate a compendium of the usage of the SECI modes and propose a framework of use, based on the strength weaknesses opportunities and threats (SWOT) findings of the study. Method: This study will employ the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology to investigate the usage and SWOT of the modes, in order to ascertain the success, or otherwise, of the sequential application of the modes in practice from 1995 to 2019. To achieve the purpose, four databases will be explored to search for open access, peer-reviewed articles from 1995 to 2019. The year 1995 is chosen as the baseline because it was the year the first paper on the SECI model was published. The study will appraise relevant peer-reviewed articles under the search terms: SECI (or its synonym, knowledge creation theory), socialization, externalization, combination, and internalization in the title, abstract, or keywords list. This review will include only empirical studies of knowledge management initiatives in which the SECI model and its modes were used. Findings: It is expected that the study will highlight the practical relevance of each mode of the SECI model, the linearity or not of the model, the SWOT in each mode. Concluding Statement: Organisations can, from the analysis, determine the modes of emphasis for their knowledge creation activities. It is expected that the study will support decision making in the choice of the SECI model as a strategy for the management of organizational knowledge resources, and in appropriating the SECI model, or its remodeled version, as a theoretical framework in future KM research.

Keywords: combination, externalisation, internalisation, knowledge management, SECI model, socialisation

Procedia PDF Downloads 315

Authors: V. K. Rajaletchumy, S. L. Chia, M. I. Setyawati, M. S. Muthu, S. S. Feng, D. T. Leong

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Triple negative breast cancers (TNBC) can be classified as one of the most aggressive with a high rate of local recurrences and systematic metastases. TNBCs are insensitive to existing hormonal therapy or targeted therapies such as the use of monoclonal antibodies, due to the lack of oestrogen receptor (ER) and progesterone receptor (PR) and the absence of overexpression of human epidermal growth factor receptor 2 (HER2) compared with other types of breast cancers. The absence of targeted therapies for selective delivery of therapeutic agents into tumours, led to the search for druggable targets in TNBC. In this study, we developed a targeted micellar system of cetuximab-conjugated micelles of D-α-tocopheryl polyethylene glycol succinate (vitamin E TPGS) for targeted delivery of docetaxel as a model anticancer drug for the treatment of TNBCs. We examined the efficacy of our micellar system in xenograft models of triple negative breast cancers and explored the effect of the micelles on post-treatment tumours in order to elucidate the mechanism underlying the nanomedicine treatment in oncology. The targeting micelles were found preferentially accumulated in tumours immediately after the administration of the micelles compare to normal tissue. The fluorescence signal gradually increased up to 12 h at the tumour site and sustained for up to 24 h, reflecting the increases in targeted micelles (TPFC) micelles in MDA-MB-231/Luc cells. In comparison, for the non-targeting micelles (TPF), the fluorescence signal was evenly distributed all over the body of the mice. Only a slight increase in fluorescence at the chest area was observed after 24 h post-injection, reflecting the moderate uptake of micelles by the tumour. The successful delivery of docetaxel into tumour by the targeted micelles (TPDC) exhibited a greater degree of tumour growth inhibition than Taxotere® after 15 days of treatment. The ex vivo study has demonstrated that tumours treated with targeting micelles exhibit enhanced cell cycle arrest and attenuated proliferation compared with the control and with those treated non-targeting micelles. Furthermore, the ex vivo investigation revealed that both the targeting and non-targeting micellar formulations shows significant inhibition of cell migration with migration indices reduced by 0.098- and 0.28-fold, respectively, relative to the control. Overall, both the in vivo and ex vivo data increased the confidence that our micellar formulations effectively targeted and inhibited EGF-overexpressing MDA-MB-231 tumours.

Keywords: biodegradable polymers, cancer nanotechnology, drug targeting, molecular biomaterials, nanomedicine

Procedia PDF Downloads 256

Authors: Shi-Bo Feng, Sheng-Jie Zhang, Jin Zhou

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The relationship between microbial diversity and algal bloom has received considerable attention for decades. Microbes undoubtedly affect annual bloom events and impact the physiology of both partners, as well as shape ecosystem diversity. However, knowledge about interactions and network correlations among broader-spectrum microbes that lead to the dynamics in a complete bloom cycle are limited. In this study, pyrosequencing and network approaches simultaneously assessed the associate patterns among bacteria, archaea, and microeukaryotes in surface water and sediments in response to a natural dinoflagellate (Alexandrium sp.) bloom. In surface water, among the bacterial community, Gamma-Proteobacteria and Bacteroidetes dominated in the initial bloom stage, while Alpha-Proteobacteria, Cyanobacteria, and Actinobacteria become the most abundant taxa during the post-stage. In the archaea biosphere, it clustered predominantly with Methanogenic members in the early pre-bloom period while the majority of species identified in the later-bloom stage were ammonia-oxidizing archaea and Halobacteriales. In eukaryotes, dinoflagellate (Alexandrium sp.) was dominated in the onset stage, whereas multiply species (such as microzooplankton, diatom, green algae, and rotifera) coexistence in bloom collapse stag. In sediments, the microbial species biomass and richness are much higher than the water body. Only Flavobacteriales and Rhodobacterales showed a slight response to bloom stages. Unlike the bacteria, there are small fluctuations of archaeal and eukaryotic structure in the sediment. The network analyses among the inter-specific associations show that bacteria (Alteromonadaceae, Oceanospirillaceae, Cryomorphaceae, and Piscirickettsiaceae) and some zooplankton (Mediophyceae, Mamiellophyceae, Dictyochophyceae and Trebouxiophyceae) have a stronger impact on the structuring of phytoplankton communities than archaeal effects. The changes in population were also significantly shaped by water temperature and substrate availability (N & P resources). The results suggest that clades are specialized at different time-periods and that the pre-bloom succession was mainly a bottom-up controlled, and late-bloom period was controlled by top-down patterns. Additionally, phytoplankton and prokaryotic communities correlated better with each other, which indicate interactions among microorganisms are critical in controlling plankton dynamics and fates. Our results supplied a wider view (temporal and spatial scales) to understand the microbial ecological responses and their network association during algal blooming. It gives us a potential multidisciplinary explanation for algal-microbe interaction and helps us beyond the traditional view linked to patterns of algal bloom initiation, development, decline, and biogeochemistry.

Keywords: microbial community, harmful algal bloom, ecological process, network

Procedia PDF Downloads 86

Authors: Natalia Buderatskaya, Igor Ilyin, Julia Gontar, Sergey Lavrynenko, Olga Parnitskaya, Ekaterina Ilyina, Eduard Kapustin, Yana Lakhno

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Introduction: It is known that cryopreservation of oocytes has peculiar features due to the complex structure of the oocyte. One of the most important features is that mature oocytes contain meiotic division spindle which is very sensitive even to the slightest variation in temperature. Thus, the main objective of this study is to analyse the resulting euploid embryos obtained from thawed oocytes in comparison with the data of preimplantation genetic screening (PGS) in fresh embryo cycles. Material and Methods: The study was conducted at 'Medical Centre IGR' from January to July 2016. Data were analysed for 908 donor oocytes obtained in 67 cycles of assisted reproductive technologies (ART), of which 693 oocytes were used in the 51 'fresh' cycles (group A), and 215 oocytes - 16 ART programs with vitrification female gametes (group B). The average age of donors in the groups match 27.3±2.9 and 27.8±6.6 years. Stimulation of superovulation was conducted the standard way. Vitrification was performed in 1-2 hours after transvaginal puncture and thawing of oocytes were carried out in accordance with the standard protocol of Cryotech (Japan). Manipulation ICSI was performed 4-5 hours after transvaginal follicle puncture for fresh oocytes, or after defrosting - for vitrified female gametes. For the PGS, an embryonic biopsy was done on the third or on the fifth day after fertilization. Diagnostic procedures were performed using fluorescence in situ hybridization with the study of such chromosomes as 13, 16, 18, 21, 22, X, Y. Only morphologically quality blastocysts were used for the transfer, the estimation of which corresponded to the Gardner criteria. The statistical hypotheses were done using the criteria t, x^2 at a significance levels p<0.05, p<0.01, p<0.001. Results: The mean number of mature oocytes per cycle in group A was 13.58±6.65 and in group B - 13.44±6.68 oocytes for patient. The survival of oocytes after thawing totaled 95.3% (n=205), which indicates a highly effective quality of performed vitrification. The proportion of zygotes in the group A corresponded to 91.1%(n=631), in the group B – 80.5%(n=165), which shows statistically significant difference between the groups (p<0.001) and explained by non-viable oocytes elimination after vitrification. This is confirmed by the fact that on the fifth day of embryos development a statistically significant difference in the number of blastocysts was absent (p>0.05), and constituted respectively 61.6%(n=389) and 63.0%(n=104) in the groups. For the PGS performing 250 embryos analyzed in the group A and 72 embryos - in the group B. The results showed that euploidy in the studied chromosomes were 40.0%(n=100) embryos in the group A and 41.7% (n=30) - in the group B, which shows no statistical significant difference (p>0.05). The indicators of clinical pregnancies in the groups amounted to 64.7% (22 pregnancies per 34 embryo transfers) and 61.5% (8 pregnancies per 13 embryo transfers) respectively, and also had no significant difference between the groups (p>0.05). Conclusions: The results showed that the vitrification does not affect the resulting euploid embryos in assisted reproductive technologies and are not reflected in their morphological characteristics in ART programs.

Keywords: euploid embryos, preimplantation genetic screening, thawing oocytes, vitrification

Procedia PDF Downloads 301

Authors: Judson P. LaGrone

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Simulation-based education in curricula was once a luxurious component of nursing programs but now serves as a vital element of an individual’s learning experience. A debriefing occurs after the simulation scenario or clinical experience is completed to allow the instructor(s) or trained professional(s) to act as a debriefer to guide a reflection with a purpose of acknowledging, assessing, and synthesizing the thought process, decision-making process, and actions/behaviors performed during the scenario or clinical experience. Debriefing is a vital component of the simulation process and educational experience to allow the learner(s) to progressively build upon past experiences and current scenarios within a safe and welcoming environment with a guided dialog to enhance future practice. The aim of this integrative review was to assess current practices of debriefing models in simulation-based education for health care professionals and students. The following databases were utilized for the search: CINAHL Plus, Cochrane Database of Systemic Reviews, EBSCO (ERIC), PsycINFO (Ovid), and Google Scholar. The advanced search option was useful to narrow down the search of articles (full text, Boolean operators, English language, peer-reviewed, published in the past five years). Key terms included debrief, debriefing, debriefing model, debriefing intervention, psychological debriefing, simulation, simulation-based education, simulation pedagogy, health care professional, nursing student, and learning process. Included studies focus on debriefing after clinical scenarios of nursing students, medical students, and interprofessional teams conducted between 2015 and 2020. Common themes were identified after the analysis of articles matching the search criteria. Several debriefing models are addressed in the literature with similarities of effectiveness for participants in clinical simulation-based pedagogy. Themes identified included (a) importance of debriefing in simulation-based pedagogy, (b) environment for which debriefing takes place is an important consideration, (c) individuals who should conduct the debrief, (d) length of debrief, and (e) methodology of the debrief. Debriefing models supported by theoretical frameworks and facilitated by trained staff are vital for a successful debriefing experience. Models differed from self-debriefing, facilitator-led debriefing, video-assisted debriefing, rapid cycle deliberate practice, and reflective debriefing. A reoccurring finding was centered around the emphasis of continued research for systematic tool development and analysis of the validity and effectiveness of current debriefing practices. There is a lack of consistency of debriefing models among nursing curriculum with an increasing rate of ill-prepared faculty to facilitate the debriefing phase of the simulation.

Keywords: debriefing model, debriefing intervention, health care professional, simulation-based education

Procedia PDF Downloads 129

Authors: Harpreet Singh Kainth

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Rubidium salts have been commonly used as an electrolyte to improve the efficiency cycle of Li-ion batteries. In recent years, it has been implemented into the large scale for further technological advances to improve the performance rate and better cyclability in the batteries. X-ray absorption spectroscopy (XAS) is a powerful tool for obtaining the information in the electronic structure which involves the chemical state analysis in the active materials used in the batteries. However, this technique is not well suited for the industrial applications because it needs a synchrotron X-ray source and special sample file for in-situ measurements. In contrast to this, conventional wavelength dispersive X-ray fluorescence (WDXRF) spectrometer is nondestructive technique used to study the chemical shift in all transitions (K, L, M, …) and does not require any special pre-preparation planning. In the present work, the fluorescent Lα, Lβ₁ , Lβ₃,₄ and Lγ₂,₃ X-ray spectra of rubidium in different chemical forms (Rb₂CO₃ , RbCl, RbBr, and RbI) have been measured first time with high resolution wavelength dispersive X-ray fluorescence (WDXRF) spectrometer (Model: S8 TIGER, Bruker, Germany), equipped with an Rh anode X-ray tube (4-kW, 60 kV and 170 mA). In ₃₇Rb compounds, the measured energy shifts are in the range (-0.45 to - 1.71) eV for Lα X-ray peak, (0.02 to 0.21) eV for Lβ₁ , (0.04 to 0.21) eV for Lβ₃ , (0.15 to 0.43) eV for Lβ₄ and (0.22 to 0.75) eV for Lγ₂,₃ X-ray emission lines. The chemical shifts in rubidium compounds have been measured by considering Rb₂CO₃ compounds taking as a standard reference. A Voigt function is used to determine the central peak position of all compounds. Both positive and negative shifts have been observed in L shell emission lines. In Lα X-ray emission lines, all compounds show negative shift while in Lβ₁, Lβ₃,₄, and Lγ₂,₃ X-ray emission lines, all compounds show a positive shift. These positive and negative shifts result increase or decrease in X-ray energy shifts. It looks like that ligands attached with central metal atom attract or repel the electrons towards or away from the parent nucleus. This pulling and pushing character of rubidium affects the central peak position of the compounds which causes a chemical shift. To understand the chemical effect more briefly, factors like electro-negativity, line intensity ratio, effective charge and bond length are responsible for the chemical state analysis in rubidium compounds. The effective charge has been calculated from Suchet and Pauling method while the line intensity ratio has been calculated by calculating the area under the relevant emission peak. In the present work, it has been observed that electro-negativity, effective charge and intensity ratio (Lβ₁/Lα, Lβ₃,₄/Lα and Lγ₂,₃/Lα) are inversely proportional to the chemical shift (RbCl > RbBr > RbI), while bond length has been found directly proportional to the chemical shift (RbI > RbBr > RbCl).

Keywords: chemical shift in L emission lines, bond length, electro-negativity, effective charge, intensity ratio, Rubidium compounds, WDXRF spectrometer

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Authors: CA Kishore S. Peshori

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Introduction: India, a country with vast diversity and huge population is going to have largest young population by 2020. Higher education has and will always be the basic requirement for making a developing nation to a developed nation. To improve any system it needs to be bench-marked. There have been various tools for bench-marking the systems. Education is delivered in India by universities which are mainly funded by government. This universities for delivering the education sets up colleges which are again funded mainly by government. Recently however there has also been autonomy given to universities and colleges. Moreover foreign universities are waiting to enter Indian boundaries. With a large number of universities and colleges it has become more and more necessary to measure this institutes for bench-marking. There have been various tools for measuring the institute. In India college assessments have been made compulsory by UGC. Naac has been offically recognised as the accrediation criteria. The Naac criteria has been based on seven criterias namely: 1. Curricular assessments, 2. Teaching learning and evaluation, 3. Research Consultancy and Extension, 4. Infrastructure and learning resources, 5. Student support and progression, 6. Governance leadership and management, 7. Innovation and best practices. The Naac tries to bench mark the institution for identification, sustainability, dissemination and adaption of best practices. It grades the institution according to this seven criteria and the funding of institution is based on these grades. Many of the colleges are struggling to get best of grades but they have not come across a systematic tool to achieve the results. Balanced Scorecard developed by Kaplan has been a successful tool for corporates to develop best of practices so as to increase their financial performance and also retain and increase their customers so as to grow the organization to next level.It is time to test this tool for an educational institute. Methodology: The paper tries to develop a prototype for college based on the secondary data. Once a prototype is developed the researcher based on questionnaire will try to test this tool for successful implementation. The success of this research will depend on its implementation of BSC on an institute and its grading improved due to this successful implementation. Limitation of time is a major constraint in this research as Naac cycle takes minimum 4 years for accreditation and reaccreditation the methodology will limit itself to secondary data and questionnaire to be circulated to colleges along with the prototype model of BSC. Conclusion: BSC is a successful tool for enhancing growth of an organization. Educational institutes are no exception to these. BSC will only have to be realigned to suit the Naac criteria. Once this prototype is developed the success will be tested only on its implementation but this research paper will be the first step towards developing this tool and will also initiate the success by developing a questionnaire and getting and evaluating the responses for moving to the next level of actual implementation

Keywords: balanced scorecard, bench marking, Naac, UGC

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Authors: Luciana S. Almeida

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Nanotechnology has revolutionized the world of science and technology bringing great expectations due to its great potential of application in the most varied industrial sectors. The same characteristics that make nanoparticles interesting from the point of view of the technological application, these may be undesirable when released into the environment. The small size of nanoparticles facilitates their diffusion and transport in the atmosphere, water, and soil and facilitates the entry and accumulation of nanoparticles in living cells. The main objective of this study is to evaluate the environmental regulatory process of nanomaterials in the Brazilian scenario. Three specific objectives were outlined. The first is to carry out a global scientometric study, in a research platform, with the purpose of identifying the main lines of study of nanomaterials in the environmental area. The second is to verify how environmental agencies in other countries have been working on this issue by means of a bibliographic review. And the third is to carry out an assessment of the Brazilian Nanotechnology Draft Law 6741/2013 with the state environmental agencies. This last one has the aim of identifying the knowledge of the subject by the environmental agencies and necessary resources available in the country for the implementation of the Policy. A questionnaire will be used as a tool for this evaluation to identify the operational elements and build indicators through the Environment of Evaluation Application, a computational application developed for the development of questionnaires. At the end will be verified the need to propose changes in the Draft Law of the National Nanotechnology Policy. Initial studies, in relation to the first specific objective, have already identified that Brazil stands out in the production of scientific publications in the area of nanotechnology, although the minority is in studies focused on environmental impact studies. Regarding the general panorama of other countries, some findings have also been raised. The United States has included the nanoform of the substances in an existing program in the EPA (Environmental Protection Agency), the TSCA (Toxic Substances Control Act). The European Union issued a draft of a document amending Regulation 1907/2006 of the European Parliament and Council to cover the nanoform of substances. Both programs are based on the study and identification of environmental risks associated with nanomaterials taking into consideration the product life cycle. In relation to Brazil, regarding the third specific objective, it is notable that the country does not have any regulations applicable to nanostructures, although there is a Draft Law in progress. In this document, it is possible to identify some requirements related to the environment, such as environmental inspection and licensing; industrial waste management; notification of accidents and application of sanctions. However, it is not known if these requirements are sufficient for the prevention of environmental impacts and if national environmental agencies will know how to apply them correctly. This study intends to serve as a basis for future actions regarding environmental management applied to the use of nanotechnology in Brazil.

Keywords: environment; management; nanotecnology; politics

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Authors: Aipeng Zhu, Yun Zhang

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The growing grievous environment problems together with the exhaustion of energy resources put urgent demands for developing high energy density. Considering the factors including capacity, resource and environment, Manganese-based lithium-rich layer-structured cathode materials xLi₂MnO₃⋅(1-x)LiMO₂ (M = Ni, Co, Mn, and other metals) are drawing increasing attention due to their high reversible capacities, high discharge potentials, and low cost. They are expected to be one type of the most promising cathode materials for the next-generation Li-ion batteries (LIBs) with higher energy densities. Unfortunately, their commercial applications are hindered with crucial drawbacks such as poor rate performance, limited cycle life and continuous falling of the discharge potential. With decades of extensive studies, significant achievements have been obtained in improving their cyclability and rate performances, but they cannot meet the requirement of commercial utilization till now. One major problem for lithium-rich layer-structured cathode materials (LLOs) is the side reaction during cycling, which leads to severe surface degradation. In this process, the metal ions can dissolve in the electrolyte, and the surface phase change can hinder the intercalation/deintercalation of Li ions and resulting in low capacity retention and low working voltage. To optimize the LLOs cathode material, the surface coating is an efficient method. Considering the price and stability, Al₂O₃ was used as a coating material in the research. Meanwhile, due to the low initial Coulombic efficiency (ICE), the pristine LLOs was pretreated by KMnO₄ to increase the ICE. The precursor was prepared by a facile coprecipitation method. The as-prepared precursor was then thoroughly mixed with Li₂CO₃ and calcined in air at 500℃ for 5h and 900℃ for 12h to produce Li₁.₂[Ni₀.₂Mn₀.₆]O₂ (LNMO). The LNMO was then put into 0.1ml/g KMnO₄ solution stirring for 3h. The resultant was filtered and washed with water, and dried in an oven. The LLOs obtained was dispersed in Al(NO₃)₃ solution. The mixture was lyophilized to confer the Al(NO₃)₃ was uniformly coated on LLOs. After lyophilization, the LLOs was calcined at 500℃ for 3h to obtain LNMO@LMO@ALO. The working electrodes were prepared by casting the mixture of active material, acetylene black, and binder (polyvinglidene fluoride) dissolved in N-methyl-2-pyrrolidone with a mass ratio of 80: 15: 5 onto an aluminum foil. The electrochemical performance tests showed that the multiple surface modified materials had a higher initial Coulombic efficiency (84%) and better capacity retention (91% after 100 cycles) compared with that of pristine LNMO (76% and 80%, respectively). The modified material suggests that the KMnO₄ pretreat and Al₂O₃ coating can increase the ICE and cycling stability.

Keywords: Li-rich materials, surface coating, lithium ion batteries, Al₂O₃

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Authors: Joao Barbosa

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After an intense dispute between the big bang cosmology and its big rival, the steady-state cosmology, some important experimental observations, such as the determination of helium abundance in the universe and the discovery of the cosmic background radiation in the 1960s were decisive for the progressive and wide acceptance of big bang cosmology and the inevitable abandonment of steady-state cosmology. But, despite solid theoretical support and those solid experimental observations favorable to big bang cosmology, Fred Hoyle, one of the proponents of the steady-state and the main opponent of the idea of the big bang (which, paradoxically, himself he baptized), never gave up and continued to fight for the idea of a stationary (or quasi-stationary) universe until the end of his life, even after decades of widespread consensus around the big bang cosmology. We can try to understand this persistent attitude of Hoyle by applying Holton’s thematic analysis to cosmology. Holton recognizes in the scientific activity a dimension that, even unconscious or not assumed, is nevertheless very important in the work of scientists, in implicit articulation with the experimental and the theoretical dimensions of science. This is the thematic dimension, constituted by themata – concepts, methodologies, and hypotheses with a metaphysical, aesthetic, logical, or epistemological nature, associated both with the cultural context and the individual psychology of scientists. In practice, themata can be expressed through personal preferences and choices that guide the individual and collective work of scientists. Thematic analysis shows that big bang cosmology is mainly based on a set of themata consisting of evolution, finitude, life cycle, and change; the cosmology of the steady-state is based on opposite themata: steady-state, infinity, continuous existence, and constancy. The passionate controversy that these cosmological views carried out is part of an old cosmological opposition: the thematic opposition between an evolutionary view of the world (associated with Heraclitus) and a stationary view (associated with Parmenides). Personal preferences seem to have been important in this (thematic) controversy, and the thematic analysis that was developed shows that Hoyle is a very illustrative example of a life-long personal commitment to some themata, in this case to the opposite themata of the big bang cosmology. His struggle against the big bang idea was strongly based on philosophical and even religious reasons – which, in a certain sense and in a Holtonian perspective, is related to thematic preferences. In this personal and persistent struggle, Hoyle always refused the way how some experimental observations were considered decisive in favor of the big bang idea, arguing that the success of this idea is based on sociological and cultural prejudices. This Hoyle’s attitude is a personal thematic attitude, in which the acceptance or rejection of what is presented as proof or scientific fact is conditioned by themata: what is a proof or a scientific fact for one scientist is something yet to be established for another scientist who defends different or even opposites themata.

Keywords: cosmology, experimental observations, fred hoyle, interpretation, life-long personal commitment, Themata

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Authors: Jollen Dai, Truman You, Xinyun Du, Katrina Liu

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Transportation is one of the leading sources of greenhouse gas emissions (GHG). Thus, to meet the Paris Agreement 2015, all countries must adopt a different and more sustainable transportation system. From bikes to Maglev, the world is slowly shifting to sustainable transportation. To develop a utility public transit system, a sustainable web of buses must be implemented. As of now, only a handful of cities have adopted a detailed plan to implement a full fleet of e-buses by the 2030s, with Shenzhen in the lead. Every change requires a detailed plan and a focused analysis of the impacts of the change. In this report, the economic implications and financial implications have been taken into consideration to develop a well-rounded 10-year plan for New York City. We also apply the same financial model to the other cities, LA and Chicago. We picked NYC, Chicago, and LA to conduct the comparative NPB analysis since they are all big metropolitan cities and have complex transportation systems. All three cities have started an action plan to achieve a full fleet of e-bus in the decades. Plus, their energy carbon footprint and their energy price are very different, which are the key factors to the benefits of electric buses. Using TCO (Total Cost Ownership) financial analysis, we developed a model to calculate NPB (Net Present Benefit) /and compare EBS (electric buses) to DBS (diesel buses). We have considered all essential aspects in our model: initial investment, including the cost of a bus, charger, and installation, government fund (federal, state, local), labor cost, energy (electricity or diesel) cost, maintenance cost, insurance cost, health and environment benefit, and V2G (vehicle to grid) benefit. We see about $1,400,000 in benefits for a 12-year lifetime of an EBS compared to DBS provided the government fund to offset 50% of EBS purchase cost. With the government subsidy, an EBS starts to make positive cash flow in 5th year and can pay back its investment in 5 years. Please remember that in our model, we consider environmental and health benefits, and every year, $50,000 is counted as health benefits per bus. Besides health benefits, the significant benefits come from the energy cost savings and maintenance savings, which are about $600,000 and $200,000 in 12-year life cycle. Using linear regression, given certain budget limitations, we then designed an optimal three-phase process to replace all NYC electric buses in 10 years, i.e., by 2033. The linear regression process is to minimize the total cost over the years and have the lowest environmental cost. The overall benefits to replace all DBS with EBS for NYC is over $2.1 billion by the year of 2033. For LA, and Chicago, the benefits for electrification of the current bus fleet are $1.04 billion and $634 million by 2033. All NPB analyses and the algorithm to optimize the electrification phase process are implemented in Python code and can be shared.

Keywords: financial modeling, total cost ownership, net present benefits, electric bus, diesel bus, NYC, LA, Chicago

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Authors: Carlos A. C. G. Neto, Natan C. G. Silva, Thais O. Costa, Luciana R. B. Goncalves, Maria v. P. Rocha

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Galactosidases are enzymes responsible for catalyzing lactose hydrolysis reactions and also favoring transgalactosylation reactions for the production of prebiotics, among which lactulose stands out. These enzymes, when immobilized, can have some enzymatic characteristics substantially improved, and the coating of supports with multifunctional polymers in immobilization processes is a promising alternative in order to extend the useful life of the biocatalysts, for example, the coating with polyethyleneimine (PEI). PEI is a flexible polymer that suits the structure of the enzyme, giving greater stability, especially for multimeric enzymes such as β-galactosidases and also protects it from environmental variations, for example, pH and temperature. In addition, it can substantially improve the immobilization parameters and also the efficiency of enzymatic reactions. In this context, the aim of the present work was first to develop biocatalysts of β-galactosidase from Kluyveromyces lactis immobilized on PEI coated agarose, determining the immobilization parameters, its operational and thermal stability, and then to apply it in the hydrolysis of lactose and synthesis of lactulose, using whey as a substrate. This immobilization strategy was chosen in order to improve the catalytic efficiency of the enzyme in the transgalactosylation reaction for the production of prebiotics, and there are few studies with β-galactosidase from this strain. The immobilization of β-galactosidase in agarose previously functionalized with 48% (w/v) glycidol and then coated with 10% (w/v) PEI solution was evaluated using an enzymatic load of 10 mg/g of protein. Subsequently, the hydrolysis and transgalactosylation reactions were conducted at 50 °C, 120 RPM for 20 minutes, using whey (66.7 g/L of lactose) supplemented with 133.3 g/L fructose at a ratio of 1:2 (lactose/fructose). Operational stability studies were performed in the same conditions for 10 cycles. Thermal stabilities of biocatalysts were conducted at 50 ºC in 50 mM phosphate buffer, pH 6.6, with 0.1 mM MnCl2. The biocatalysts whose supports were coated were named AGA_GLY_PEI_GAL, and those that were not coated were named AGA_GLY_GAL. The coating of the support with PEI considerably improved immobilization yield (2.6-fold), the biocatalyst activity (1.4-fold), and efficiency (2.2-fold). The biocatalyst AGA_GLY_PEI_GAL was better than AGA_GLY_GAL in hydrolysis and transgalactosylation reactions, converting 88.92% of lactose at 5 min of reaction and obtaining a residual concentration of 5.24 g/L. Besides that, it was produced 13.90 g/L lactulose in the same time interval. AGA_GLY_PEI_GAL biocatalyst was stable during the 10 cycles evaluated, converting approximately 80% of lactose and producing 10.95 g/L of lactulose even after the tenth cycle. However, the thermal stability of AGA_GLY_GAL biocatalyst was superior, with a half-life time 5 times higher, probably because the enzyme was immobilized by covalent bonding, which is stronger than adsorption (AGA_GLY_PEI_GAL). Therefore, the strategy of coating the supports with PEI has proven to be effective for the immobilization of β-galactosidase from K. lactis, considerably improving the immobilization parameters, as well as the enzyme, catalyzed reactions. In addition, the use of whey as a raw material for lactulose production has proved to be an industrially advantageous alternative.

Keywords: β-galactosidase, immobilization, lactulose, polyethylenimine, whey

Procedia PDF Downloads 97