Search results for: controversial environmental sustainability issues
Commenced in January 2007
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Edition: International
Paper Count: 12039

Search results for: controversial environmental sustainability issues

369 Reactivities of Turkish Lignites during Oxygen Enriched Combustion

Authors: Ozlem Uguz, Ali Demirci, Hanzade Haykiri-Acma, Serdar Yaman

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Lignitic coal holds its position as Turkey’s most important indigenous energy source to generate energy in thermal power plants. Hence, efficient and environmental-friendly use of lignite in electricity generation is of great importance. Thus, clean coal technologies have been planned to mitigate emissions and provide more efficient burning in power plants. In this context, oxygen enriched combustion (oxy-combustion) is regarded as one of the clean coal technologies, which based on burning with oxygen concentrations higher than that in air. As it is known that the most of the Turkish coals are low rank with high mineral matter content, unburnt carbon trapped in ash is, unfortunately, high, and it leads significant losses in the overall efficiencies of the thermal plants. Besides, the necessity of burning huge amounts of these low calorific value lignites to get the desired amount of energy also results in the formation of large amounts of ash that is rich in unburnt carbon. Oxygen enriched combustion technology enables to increase the burning efficiency through the complete burning of almost all of the carbon content of the fuel. This also contributes to the protection of air quality and emission levels drop reasonably. The aim of this study is to investigate the unburnt carbon content and the burning reactivities of several different lignite samples under oxygen enriched conditions. For this reason, the combined effects of temperature and oxygen/nitrogen ratios in the burning atmosphere were investigated and interpreted. To do this, Turkish lignite samples from Adıyaman-Gölbaşı and Kütahya-Tunçbilek regions were characterized first by proximate and ultimate analyses and the burning profiles were derived using DTA (Differential Thermal Analysis) curves. Then, these lignites were subjected to slow burning process in a horizontal tube furnace at different temperatures (200ºC, 400ºC, 600ºC for Adıyaman-Gölbaşı lignite and 200ºC, 450ºC, 800ºC for Kütahya-Tunçbilek lignite) under atmospheres having O₂+N₂ proportions of 21%O₂+79%N₂, 30%O₂+70%N₂, 40%O₂+60%N₂, and 50%O₂+50%N₂. These burning temperatures were specified based on the burning profiles derived from the DTA curves. The residues obtained from these burning tests were also analyzed by proximate and ultimate analyses to detect the unburnt carbon content along with the unused energy potential. Reactivity of these lignites was calculated using several methodologies. Burning yield under air condition (21%O₂+79%N₂) was used a benchmark value to compare the effectiveness of oxygen enriched conditions. It was concluded that oxygen enriched combustion method enhanced the combustion efficiency and lowered the unburnt carbon content of ash. Combustion of low-rank coals under oxygen enriched conditions was found to be a promising way to improve the efficiency of the lignite-firing energy systems. However, cost-benefit analysis should be considered for a better justification of this method since the use of more oxygen brings an unignorable additional cost.

Keywords: coal, energy, oxygen enriched combustion, reactivity

Procedia PDF Downloads 253
368 Cotton Fabrics Functionalized with Green and Commercial Ag Nanoparticles

Authors: Laura Gonzalez, Santiago Benavides, Martha Elena Londono, Ana Elisa Casas, Adriana Restrepo-Osorio

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Cotton products are sensitive to microorganisms due to its ability to retain moisture, which might cause change into the coloration, mechanical properties reduction or foul odor generation; consequently, this represents risks to the health of users. Nowadays, have been carried out researches to give antibacterial properties to textiles using different strategies, which included the use of silver nanoparticles (AgNPs). The antibacterial behavior can be affected by laundering process reducing its effectiveness. In the other way, the environmental impact generated for the synthetic antibacterial agents has motivated to seek new and more ecological ways for produce AgNPs. The aims of this work are to determine the antibacterial activity of cotton fabric functionalized with green (G) and commercial (C) AgNPs after twenty washing cycles, also to evaluate morphological and color changes. A plain weave cotton fabric suitable for dyeing and two AgNPs solutions were use. C a commercial product and G produced using an ecological method, both solutions with 0.5 mM concentration were impregnated on cotton fabric without stabilizer, at a liquor to fabric ratio of 1:20 in constant agitation during 30min and then dried at 70 °C by 10 min. After that the samples were subjected to twenty washing cycles using phosphate-free detergent simulated on agitated flask at 150 rpm, then were centrifuged and dried on a tumble. The samples were characterized using Kirby-Bauer test determine antibacterial activity against E. coli y S. aureus microorganisms, the results were registered by photographs establishing the inhibition halo before and after the washing cycles, the tests were conducted in triplicate. Scanning electron microscope (SEM) was used to observe the morphologies of cotton fabric and treated samples. The color changes of cotton fabrics in relation to the untreated samples were obtained by spectrophotometer analysis. The images, reveals the presence of inhibition halo in the samples treated with C and G AgNPs solutions, even after twenty washing cycles, which indicated a good antibacterial activity and washing durability, with a tendency to better results against to S. aureus bacteria. The presence of AgNPs on the surface of cotton fiber and morphological changes were observed through SEM, after and before washing cycles. The own color of the cotton fiber has been significantly altered with both antibacterial solutions. According to the colorimetric results, the samples treated with C lead to yellowing while the samples modified with G to red yellowing Cotton fabrics treated AgNPs C and G from 0.5 mM solutions exhibited excellent antimicrobial activity against E. coli and S. aureus with good laundering durability effects. The surface of the cotton fibers was modified with the presence of AgNPs C and G due to the presence of NPs and its agglomerates. There are significant changes in the natural color of cotton fabric due to deposition of AgNPs C and G which were maintained after laundering process.

Keywords: antibacterial property, cotton fabric, fastness to wash, Kirby-Bauer test, silver nanoparticles

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367 Hygro-Thermal Modelling of Timber Decks

Authors: Stefania Fortino, Petr Hradil, Timo Avikainen

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Timber bridges have an excellent environmental performance, are economical, relatively easy to build and can have a long service life. However, the durability of these bridges is the main problem because of their exposure to outdoor climate conditions. The moisture content accumulated in wood for long periods, in combination with certain temperatures, may cause conditions suitable for timber decay. In addition, moisture content variations affect the structural integrity, serviceability and loading capacity of timber bridges. Therefore, the monitoring of the moisture content in wood is important for the durability of the material but also for the whole superstructure. The measurements obtained by the usual sensor-based techniques provide hygro-thermal data only in specific locations of the wood components. In this context, the monitoring can be assisted by numerical modelling to get more information on the hygro-thermal response of the bridges. This work presents a hygro-thermal model based on a multi-phase moisture transport theory to predict the distribution of moisture content, relative humidity and temperature in wood. Below the fibre saturation point, the multi-phase theory simulates three phenomena in cellular wood during moisture transfer, i.e., the diffusion of water vapour in the pores, the sorption of bound water and the diffusion of bound water in the cell walls. In the multi-phase model, the two water phases are separated, and the coupling between them is defined through a sorption rate. Furthermore, an average between the temperature-dependent adsorption and desorption isotherms is used. In previous works by some of the authors, this approach was found very suitable to study the moisture transport in uncoated and coated stress-laminated timber decks. Compared to previous works, the hygro-thermal fluxes on the external surfaces include the influence of the absorbed solar radiation during the time and consequently, the temperatures on the surfaces exposed to the sun are higher. This affects the whole hygro-thermal response of the timber component. The multi-phase model, implemented in a user subroutine of Abaqus FEM code, provides the distribution of the moisture content, the temperature and the relative humidity in a volume of the timber deck. As a case study, the hygro-thermal data in wood are collected from the ongoing monitoring of the stress-laminated timber deck of Tapiola Bridge in Finland, based on integrated humidity-temperature sensors and the numerical results are found in good agreement with the measurements. The proposed model, used to assist the monitoring, can contribute to reducing the maintenance costs of bridges, as well as the cost of instrumentation, and increase safety.

Keywords: moisture content, multi-phase models, solar radiation, timber decks, FEM

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366 From By-product To Brilliance: Transforming Adobe Brick Construction Using Meat Industry Waste-derived Glycoproteins

Authors: Amal Balila, Maria Vahdati

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Earth is a green building material with very low embodied energy and almost zero greenhouse gas emissions. However, it lacks strength and durability in its natural state. By responsibly sourcing stabilisers, it's possible to enhance its strength. This research draws inspiration from the robustness of termite mounds, where termites incorporate glycoproteins from their saliva during construction. Biomimicry explores the potential of these termite stabilisers in producing bio-inspired adobe bricks. The meat industry generates significant waste during slaughter, including blood, skin, bones, tendons, gastrointestinal contents, and internal organs. While abundant, many meat by-products raise concerns regarding human consumption, religious orders, cultural and ethical beliefs, and also heavily contribute to environmental pollution. Extracting and utilising proteins from this waste is vital for reducing pollution and increasing profitability. Exploring the untapped potential of meat industry waste, this research investigates how glycoproteins could revolutionize adobe brick construction. Bovine serum albumin (BSA) from cows' blood and mucin from porcine stomachs were the chosen glycoproteins used as stabilisers for adobe brick production. Despite their wide usage across various fields, they have very limited utilisation in food processing. Thus, both were identified as potential stabilisers for adobe brick production in this study. Two soil types were utilised to prepare adobe bricks for testing, comparing controlled unstabilised bricks with glycoprotein-stabilised ones. All bricks underwent testing for unconfined compressive strength and erosion resistance. The primary finding of this study is the efficacy of BSA, a glycoprotein derived from cows' blood and a by-product of the beef industry, as an earth construction stabiliser. Adding 0.5% by weight of BSA resulted in a 17% and 41% increase in the unconfined compressive strength for British and Sudanese adobe bricks, respectively. Further, adding 5% by weight of BSA led to a 202% and 97% increase in the unconfined compressive strength for British and Sudanese adobe bricks, respectively. Moreover, using 0.1%, 0.2%, and 0.5% by weight of BSA resulted in erosion rate reductions of 30%, 48%, and 70% for British adobe bricks, respectively, with a 97% reduction observed for Sudanese adobe bricks at 0.5% by weight of BSA. However, mucin from the porcine stomach did not significantly improve the unconfined compressive strength of adobe bricks. Nevertheless, employing 0.1% and 0.2% by weight of mucin resulted in erosion rate reductions of 28% and 55% for British adobe bricks, respectively. These findings underscore BSA's efficiency as an earth construction stabiliser for wall construction and mucin's efficacy for wall render, showcasing their potential for sustainable and durable building practices.

Keywords: biomimicry, earth construction, industrial waste management, sustainable building materials, termite mounds.

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365 An Absolute Femtosecond Rangefinder for Metrological Support in Coordinate Measurements

Authors: Denis A. Sokolov, Andrey V. Mazurkevich

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In the modern world, there is an increasing demand for highly precise measurements in various fields, such as aircraft, shipbuilding, and rocket engineering. This has resulted in the development of appropriate measuring instruments that are capable of measuring the coordinates of objects within a range of up to 100 meters, with an accuracy of up to one micron. The calibration process for such optoelectronic measuring devices (trackers and total stations) involves comparing the measurement results from these devices to a reference measurement based on a linear or spatial basis. The reference used in such measurements could be a reference base or a reference range finder with the capability to measure angle increments (EDM). The base would serve as a set of reference points for this purpose. The concept of the EDM for replicating the unit of measurement has been implemented on a mobile platform, which allows for angular changes in the direction of laser radiation in two planes. To determine the distance to an object, a high-precision interferometer with its own design is employed. The laser radiation travels to the corner reflectors, which form a spatial reference with precisely known positions. When the femtosecond pulses from the reference arm and the measuring arm coincide, an interference signal is created, repeating at the frequency of the laser pulses. The distance between reference points determined by interference signals is calculated in accordance with recommendations from the International Bureau of Weights and Measures for the indirect measurement of time of light passage according to the definition of a meter. This distance is D/2 = c/2nF, approximately 2.5 meters, where c is the speed of light in a vacuum, n is the refractive index of a medium, and F is the frequency of femtosecond pulse repetition. The achieved uncertainty of type A measurement of the distance to reflectors 64 m (N•D/2, where N is an integer) away and spaced apart relative to each other at a distance of 1 m does not exceed 5 microns. The angular uncertainty is calculated theoretically since standard high-precision ring encoders will be used and are not a focus of research in this study. The Type B uncertainty components are not taken into account either, as the components that contribute most do not depend on the selected coordinate measuring method. This technology is being explored in the context of laboratory applications under controlled environmental conditions, where it is possible to achieve an advantage in terms of accuracy. In general, the EDM tests showed high accuracy, and theoretical calculations and experimental studies on an EDM prototype have shown that the uncertainty type A of distance measurements to reflectors can be less than 1 micrometer. The results of this research will be utilized to develop a highly accurate mobile absolute range finder designed for the calibration of high-precision laser trackers and laser rangefinders, as well as other equipment, using a 64 meter laboratory comparator as a reference.

Keywords: femtosecond laser, pulse correlation, interferometer, laser absolute range finder, coordinate measurement

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364 Immobilization of β-Galactosidase from Kluyveromyces Lactis on Polyethylenimine-Agarose for Production of Lactulose

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

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363 Identifying the Needs for Renewal of Urban Water Infrastructure Systems: Analysis of Material, Age, Types and Areas: Case Study of Linköping in Sweden

Authors: Eman Hegazy, Stefan Anderberg, Joakim Krook

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Urban water infrastructure is crucial for efficient and reliable water supply in growing cities. With the growth of cities, the need for maintenance and renewal of these systems increases but often goes unfulfilled due to a variety of reasons, such as limited funding, political priorities, or lack of public awareness. Neglecting the renewal needs of these systems can lead to frequent malfunctions and reduced quality and reliability of water supply, as well as increased costs and health and environmental hazards. It is important for cities to prioritize investment in water infrastructure and develop long-term plans to address renewal needs. Drawing general conclusions about the rate of renewal of urban water infrastructure systems at an international or national level can be challenging due to the influence of local management decisions. In many countries, the responsibility for water infrastructure management lies with the municipal authorities, who are responsible for making decisions about the allocation of resources for repair, maintenance, and renewal. These decisions can vary widely based on factors such as local finances, political priorities, and public perception of the importance of water infrastructure. As a result, it is difficult to make generalizations about the rate of renewal across different countries or regions. In Sweden, the situation is not different, and the information from Svenskt Vatten indicates that the rate of renewal varies across municipalities and can be insufficient, leading to a buildup of maintenance and renewal needs. This study aims to examine the adequacy of the rate of renewal of urban water infrastructure in Linköping case city in Sweden. Using a case study framework, the study will assess the current status of the urban water system and the need for renewal. The study will also consider the role of factors such as proper identification processes, limited funding, competing for political priorities, and local management decisions in contributing to insufficient renewal. The study investigates the following questions: (1) What is the current status of water and sewerage networks in terms of length, age distribution, and material composition, estimated total water leakage in the network per year, damages, leaks, and outages occur per year, both overall and by district? (2) What are the main causes of these damages, leaks, and interruptions, and how are they related to lack of maintenance and renewal? (3) What is the current status of renewal work for the water and sewerage networks, including the renewal rate and changes over time, recent renewal material composition, and the budget allocation for renewal and emergency repairs? (4) What factors influence the need for renewal and what conditions should be considered in the assessment? The findings of the study provide insights into the challenges facing urban water infrastructure and identify strategies for improving the rate of renewal to ensure a reliable and sustainable water supply.

Keywords: case study, infrastructure, management, renewal need, Sweden

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362 Generating Ideas to Improve Road Intersections Using Design with Intent Approach

Authors: Omar Faruqe Hamim, M. Shamsul Hoque, Rich C. McIlroy, Katherine L. Plant, Neville A. Stanton

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Road safety has become an alarming issue, especially in low-middle income developing countries. The traditional approaches lack the out of the box thinking, making engineers confined to applying usual techniques in making roads safer. A socio-technical approach has recently been introduced in improving road intersections through designing with intent. This Design With Intent (DWI) approach aims to give practitioners a more nuanced approach to design and behavior, working with people, people’s understanding, and the complexities of everyday human experience. It's a collection of design patterns —and a design and research approach— for exploring the interactions between design and people’s behavior across products, services, and environments, both digital and physical. Through this approach, it can be seen that how designing with people in behavior change can be applied to social and environmental problems, as well as commercially. It has a total of 101 cards across eight different lenses, such as architectural, error-proofing, interaction, ludic, perceptual, cognitive, Machiavellian, and security lens each having its own distinct characteristics of extracting ideas from the participant of this approach. For this research purpose, a three-legged accident blackspot intersection of a national highway has been chosen to perform the DWI workshop. Participants from varying fields such as civil engineering, naval architecture and marine engineering, urban and regional planning, and sociology actively participated for a day long workshop. While going through the workshops, the participants were given a preamble of the accident scenario and a brief overview of DWI approach. Design cards of varying lenses were distributed among 10 participants and given an hour and a half for brainstorming and generating ideas to improve the safety of the selected intersection. After the brainstorming session, the participants spontaneously went through roundtable discussions regarding the ideas they have come up with. According to consensus of the forum, ideas were accepted or rejected. These generated ideas were then synthesized and agglomerated to bring about an improvement scheme for the intersection selected in our study. To summarize the improvement ideas from DWI approach, color coding of traffic lanes for separate vehicles, channelizing the existing bare intersection, providing advance warning traffic signs, cautionary signs and educational signs motivating road users to drive safe, using textured surfaces at approach with rumble strips before the approach of intersection were the most significant one. The motive of this approach is to bring about new ideas from the road users and not just depend on traditional schemes to increase the efficiency, safety of roads as well and to ensure the compliance of road users since these features are being generated from the minds of users themselves.

Keywords: design with intent, road safety, human experience, behavior

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361 Cloning and Expression a Gene of β-Glucosidase from Penicillium echinulatum in Pichia pastoris

Authors: Amanda Gregorim Fernandes, Lorena Cardoso Cintra, Rosalia Santos Amorim Jesuino, Fabricia Paula De Faria, Marcio José Poças Fonseca

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Bioethanol is one of the most promising biofuels and able to replace fossil fuels and reduce its different environmental impacts and can be generated from various agroindustrial waste. The Brazil is in first place in bioethanol production to be the largest producer of sugarcane. The bagasse sugarcane (SCB) has lignocellulose which is composed of three major components: cellulose, hemicellulose and lignin. Cellulose is a homopolymer of glucose units connected by glycosidic linkages. Among all species of Penicillium, Penicillium echinulatum has been the focus of attention because they produce high quantities of cellulase and the mutant strain 9A02S1 produces higher enzyme levels compared to the wild. Among the cellulases, the cellobiohydrolases enzymes are the main components of the cellulolytic system of fungi, and are also responsible for most of the potential hydrolytic in enzyme cocktails for the industrial processing of plant biomass and several cellobiohydrolases Penicillium had higher specific activity against cellulose compared to CBH I from Trichoderma reesei. This fact makes it an interesting pattern for higher yields in the enzymatic hydrolysis, and also they are important enzymes in the hydrolysis of crystalline regions of cellulose. Therefore, finding new and more active enzymes become necessary. Meanwhile, β-glycosidases act on soluble substrates and are highly dependent on cellobiohydrolases and endoglucanases action to provide the substrate in the hydrolysis of the biomass, but the cellobiohydrolases and endoglucanases are highly dependent β-glucosidases to maintain efficient hydrolysis. Thus, there is a need to understand the structure-function relationships that govern the catalytic activity of cellulolytic enzymes to elucidate its mechanism of action and optimize its potential as industrial biocatalysts. To evaluate the enzyme β-glucosidase of Penicillium echinulatum (PeBGL1) the gene was synthesized from the assembly sequence from a library in induction conditions and then the PeBGL1 gene was cloned in the vector pPICZαA and transformed into P. pastoris GS115. After processing, the producers of PeBGL1 were analyzed for enzyme activity and protein profile where a band of approximately 100 kDa was viewed. It was also carried out the zymogram. In partial characterization it was determined optimum temperature of 50°C and optimum pH of 6,5. In addition, to increase the secreted recombinant PeBGL1 production by Pichia pastoris, three parameters of P. pastoris culture medium were analysed: methanol, nitrogen source concentrations and the inoculum size. A 23 factorial design was effective in achieving the optimum condition. Altogether, these results point to the potential application of this P. echinulatum β-glucosidase in hydrolysis of cellulose for the production of bioethanol.

Keywords: bioethanol, biotechnology, beta-glucosidase, penicillium echinulatum

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360 The Effect of Slum Neighborhoods on Pregnancy Outcomes in Tanzania: Secondary Analysis of the 2015-2016 Tanzania Demographic and Health Survey Data

Authors: Luisa Windhagen, Atsumi Hirose, Alex Bottle

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Global urbanization has resulted in the expansion of slums, leaving over 10 million Tanzanians in urban poverty and at risk of poor health. Whilst rural residence has historically been associated with an increased risk of adverse pregnancy outcomes, recent studies found higher perinatal mortality rates in urban Tanzania. This study aims to understand to what extent slum neighborhoods may account for the spatial disparities seen in Tanzania. We generated a slum indicator based on UN-HABITAT criteria to identify slum clusters within the 2015-2016 Tanzania Demographic and Health Survey. Descriptive statistics, disaggregated by urban slum, urban non-slum, and rural areas, were produced. Simple and multivariable logistic regression examined the association between cluster residence type and neonatal mortality and stillbirth. For neonatal mortality, we additionally built a multilevel logistic regression model, adjusting for confounding and clustering. The neonatal mortality ratio was highest in slums (38.3 deaths per 1000 live births); the stillbirth rate was three times higher in slums (32.4 deaths per 1000 births) than in urban non-slums. Neonatal death was more likely to occur in slums than in urban non-slums (aOR=2.15, 95% CI=1.02-4.56) and rural areas (aOR=1.78, 95% CI=1.15-2.77). Odds of stillbirth were over five times higher among rural than urban non-slum residents (aOR=5.25, 95% CI=1.31-20.96). The results suggest that slums contribute to the urban disadvantage in Tanzanian neonatal health. Higher neonatal mortality in slums may be attributable to lack of education, lower socioeconomic status, poor healthcare access, and environmental factors, including indoor and outdoor air pollution and unsanitary conditions from inadequate housing. However, further research is required to ascertain specific causalities as well as significant associations between residence type and other pregnancy outcomes. The high neonatal mortality, stillbirth, and slum formation rates in Tanzania signify that considerable change is necessary to achieve international goals for health and human settlements. Disparities in access to adequate housing, safe water and sanitation, high standard antenatal, intrapartum, and neonatal care, and maternal education need to urgently be addressed. This study highlights the spatial neonatal mortality shift from rural settings to urban informal settlements in Tanzania. Importantly, other low- and middle-income countries experiencing overwhelming urbanization and slum expansion may also be at risk of a reversing trend in residential neonatal health differences.

Keywords: urban health, slum residence, neonatal mortality, stillbirth, global urbanisation

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359 Genetically Modified Fuel-Ethanol Industrial Yeast Strains as Biocontrol Agents

Authors: Patrícia Branco, Catarina Prista, Helena Albergaria

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Industrial fuel-ethanol fermentations are carried out under non-sterile conditions, which favors the development of microbial contaminants, leading to huge economic losses. Wild yeasts such as Brettanomyces bruxellensis and lactic acid bacteria are the main contaminants of industrial bioethanol fermentation, affecting Saccharomyces cerevisiae performance and decreasing ethanol yields and productivity. In order to control microbial contaminations, the fuel-ethanol industry uses different treatments, including acid washing and antibiotics. However, these control measures carry environmental risks such as acid toxicity and the rise of antibiotic-resistant bacteria. Therefore, it is crucial to develop and apply less toxic and more environmentally friendly biocontrol methods. In the present study, an industrial fuel-ethanol starter, S. cerevisiae Ethanol-Red, was genetically modified to over-express AMPs with activity against fuel-ethanol microbial contaminants and evaluated regarding its biocontrol effect during mixed-culture alcoholic fermentations artificially contaminated with B. bruxellensis. To achieve this goal, S. cerevisiae Ethanol-Red strain was transformed with a plasmid containing the AMPs-codifying genes, i.e., partial sequences of TDH1 (925-963 bp) and TDH2/3 (925-963 bp) and a geneticin resistance marker. The biocontrol effect of those genetically modified strains was evaluated against B. bruxellensis and compared with the antagonistic effect exerted by the modified strain with an empty plasmid (without the AMPs-codifying genes) and the non-modified strain S. cerevisiae Ethanol-Red. For that purpose, mixed-culture alcoholic fermentations were performed in a synthetic must use the modified S. cerevisiae Ethanol-Red strains together with B. bruxellensis. Single-culture fermentations of B. bruxellensis strains were also performed as a negative control of the antagonistic effect exerted by S. cerevisiae strains. Results clearly showed an improved biocontrol effect of the genetically-modified strains against B. bruxellensis when compared with the modified Ethanol-Red strain with the empty plasmid (without the AMPs-codifying genes) and with the non-modified Ethanol-Red strain. In mixed-culture fermentation with the modified S. cerevisiae strain, B. bruxellensis culturability decreased from 5×104 CFU/mL on day-0 to less than 1 CFU/mL on day-10, while in single-culture B. bruxellensis increased its culturability from 6×104 to 1×106 CFU/mL in the first 6 days and kept this value until day-10. Besides, the modified Ethanol-Red strain exhibited an enhanced antagonistic effect against B. bruxellensis when compared with that induced by the non-modified Ethanol-Red strain. Indeed, culturability loss of B. bruxellensis after 10 days of fermentation with the modified Ethanol-Red strain was 98.7 and 100% higher than that occurred in fermentations performed with the non-modified Ethanol-Red and the empty-plasmid modified strain, respectively. Therefore, one can conclude that the S. cerevisiae genetically modified strain obtained in the present work may be a valuable solution for the mitigation of microbial contamination in fuel-ethanol fermentations, representing a much safer and environmentally friendly preservation strategy than the antimicrobial treatments (acid washing and antibiotics) currently applied in fuel-ethanol industry.

Keywords: antimicrobial peptides, fuel-ethanol microbial contaminations, fuel-ethanol fermentation, biocontrol agents, genetically-modified yeasts

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358 Electrohydrodynamic Patterning for Surface Enhanced Raman Scattering for Point-of-Care Diagnostics

Authors: J. J. Rickard, A. Belli, P. Goldberg Oppenheimer

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Medical diagnostics, environmental monitoring, homeland security and forensics increasingly demand specific and field-deployable analytical technologies for quick point-of-care diagnostics. Although technological advancements have made optical methods well-suited for miniaturization, a highly-sensitive detection technique for minute sample volumes is required. Raman spectroscopy is a well-known analytical tool, but has very weak signals and hence is unsuitable for trace level analysis. Enhancement via localized optical fields (surface plasmons resonances) on nanoscale metallic materials generates huge signals in surface-enhanced Raman scattering (SERS), enabling single molecule detection. This enhancement can be tuned by manipulation of the surface roughness and architecture at the sub-micron level. Nevertheless, the development and application of SERS has been inhibited by the irreproducibility and complexity of fabrication routes. The ability to generate straightforward, cost-effective, multiplex-able and addressable SERS substrates with high enhancements is of profound interest for SERS-based sensing devices. While most SERS substrates are manufactured by conventional lithographic methods, the development of a cost-effective approach to create nanostructured surfaces is a much sought-after goal in the SERS community. Here, a method is established to create controlled, self-organized, hierarchical nanostructures using electrohydrodynamic (HEHD) instabilities. The created structures are readily fine-tuned, which is an important requirement for optimizing SERS to obtain the highest enhancements. HEHD pattern formation enables the fabrication of multiscale 3D structured arrays as SERS-active platforms. Importantly, each of the HEHD-patterned individual structural units yield a considerable SERS enhancement. This enables each single unit to function as an isolated sensor. Each of the formed structures can be effectively tuned and tailored to provide high SERS enhancement, while arising from different HEHD morphologies. The HEHD fabrication of sub-micrometer architectures is straightforward and robust, providing an elegant route for high-throughput biological and chemical sensing. The superior detection properties and the ability to fabricate SERS substrates on the miniaturized scale, will facilitate the development of advanced and novel opto-fluidic devices, such as portable detection systems, and will offer numerous applications in biomedical diagnostics, forensics, ecological warfare and homeland security.

Keywords: hierarchical electrohydrodynamic patterning, medical diagnostics, point-of care devices, SERS

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357 Microalgae Technology for Nutraceuticals

Authors: Weixing Tan

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Production of nutraceuticals from microalgae—a virtually untapped natural phyto-based source of which there are 200,000 to 1,000,000 species—offers a sustainable and healthy alternative to conventionally sourced nutraceuticals for the market. Microalgae can be grown organically using only natural sunlight, water and nutrients at an extremely fast rate, e.g. 10-100 times more efficiently than crops or trees. However, the commercial success of microalgae products at scale remains limited largely due to the lack of economically viable technologies. There are two major microalgae production systems or technologies currently available: 1) the open system as represented by open pond technology and 2) the closed system such as photobioreactors (PBR). Each carries its own unique features and challenges. Although an open system requires a lower initial capital investment relative to a PBR, it conveys many unavoidable drawbacks; for example, much lower productivity, difficulty in contamination control/cleaning, inconsistent product quality, inconvenience in automation, restriction in location selection, and unsuitability for cold areas – all directly linked to the system openness and flat underground design. On the other hand, a PBR system has characteristics almost entirely opposite to the open system, such as higher initial capital investment, better productivity, better contamination and environmental control, wider suitability in different climates, ease in automation, higher and consistent product quality, higher energy demand (particularly if using artificial lights), and variable operational expenses if not automated. Although closed systems like PBRs are not highly competitive yet in current nutraceutical supply market, technological advances can be made, in particular for the PBR technology, to narrow the gap significantly. One example is a readily scalable P2P Microalgae PBR Technology at Grande Prairie Regional College, Canada, developed over 11 years considering return on investment (ROI) for key production processes. The P2P PBR system is approaching economic viability at a pre-commercial stage due to five ROI-integrated major components. They include: (1) optimum use of free sunlight through attenuation (patented); (2) simple, economical, and chemical-free harvesting (patent ready to file); (3) optimum pH- and nutrient-balanced culture medium (published), (4) reliable water and nutrient recycling system (trade secret); and (5) low-cost automated system design (trade secret). These innovations have allowed P2P Microalgae Technology to increase daily yield to 106 g/m2/day of Chlorella vulgaris, which contains 50% proteins and 2-3% omega-3. Based on the current market prices and scale-up factors, this P2P PBR system presents as a promising microalgae technology for market competitive nutraceutical supply.

Keywords: microalgae technology, nutraceuticals, open pond, photobioreactor PBR, return on investment ROI, technological advances

Procedia PDF Downloads 137
356 p-Type Multilayer MoS₂ Enabled by Plasma Doping for Ultraviolet Photodetectors Application

Authors: Xiao-Mei Zhang, Sian-Hong Tseng, Ming-Yen Lu

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Two-dimensional (2D) transition metal dichalcogenides (TMDCs), such as MoS₂, have attracted considerable attention owing to the unique optical and electronic properties related to its 2D ultrathin atomic layer structure. MoS₂ is becoming prevalent in post-silicon digital electronics and in highly efficient optoelectronics due to its extremely low thickness and its tunable band gap (Eg = 1-2 eV). For low-power, high-performance complementary logic applications, both p- and n-type MoS₂ FETs (NFETs and PFETs) must be developed. NFETs with an electron accumulation channel can be obtained using unintentionally doped n-type MoS₂. However, the fabrication of MoS₂ FETs with complementary p-type characteristics is challenging due to the significant difficulty of injecting holes into its inversion channel. Plasma treatments with different species (including CF₄, SF₆, O₂, and CHF₃) have also been found to achieve the desired property modifications of MoS₂. In this work, we demonstrated a p-type multilayer MoS₂ enabled by selective-area doping using CHF₃ plasma treatment. Compared with single layer MoS₂, multilayer MoS₂ can carry a higher drive current due to its lower bandgap and multiple conduction channels. Moreover, it has three times the density of states at its minimum conduction band. Large-area growth of MoS₂ films on 300 nm thick SiO₂/Si substrate is carried out by thermal decomposition of ammonium tetrathiomolybdate, (NH₄)₂MoS₄, in a tube furnace. A two-step annealing process is conducted to synthesize MoS₂ films. For the first step, the temperature is set to 280 °C for 30 min in an N₂ rich environment at 1.8 Torr. This is done to transform (NH₄)₂MoS₄ into MoS₃. To further reduce MoS₃ into MoS₂, the second step of annealing is performed. For the second step, the temperature is set to 750 °C for 30 min in a reducing atmosphere consisting of 90% Ar and 10% H₂ at 1.8 Torr. The grown MoS₂ films are subjected to out-of-plane doping by CHF₃ plasma treatment using a Dry-etching system (ULVAC original NLD-570). The radiofrequency power of this dry-etching system is set to 100 W and the pressure is set to 7.5 mTorr. The final thickness of the treated samples is obtained by etching for 30 s. Back-gated MoS₂ PFETs were presented with an on/off current ratio in the order of 10³ and a field-effect mobility of 65.2 cm²V⁻¹s⁻¹. The MoS₂ PFETs photodetector exhibited ultraviolet (UV) photodetection capability with a rapid response time of 37 ms and exhibited modulation of the generated photocurrent by back-gate voltage. This work suggests the potential application of the mild plasma-doped p-type multilayer MoS₂ in UV photodetectors for environmental monitoring, human health monitoring, and biological analysis.

Keywords: photodetection, p-type doping, multilayers, MoS₂

Procedia PDF Downloads 83
355 The Architectural Conservation and Restoration Problems of Mevlevihanes

Authors: Zeynep Tanrıverdi, Ş. Barihüda Tanrıkorur

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Mevlevihanes are the dervish lodges of the Mevlevi Sufi Order of dervishes, which was founded on the teachings of Mevlâna Jalaluddin Rumi (1207-1273) in the late 13th century in the Anatolian city of Konya, from which they were administered until 1925, when their activities together with all other sufi dervish orders, were legally prohibited after the founding of the Turkish Republic. On their closure in 1925 over 150 mevlevihane architectural complexes, which had functioned for over 600 years through the late Seljuk, Emirates, and Ottoman periods of Turkish history, were to be found in the geographic areas that had been once occupied by the Ottoman Empire. Unfortunately, because of the history of their prohibition and closure after 1925, the public developed confused negative reactions towards sufi dervish orders and their buildings occupied a nebulous political status so that their upkeep and restoration became neglected, they were used for different, inappropriate functions or were abandoned within the Turkish Republic, until a more socially objective, educated viewpoint developed in the late 1970’s and 80’s. The declaration of the Mevlevi Ayin-i Şerifi (the Ritual Whirling Ceremony of the Mevlevi Dervish Order) with its complex composed music and sema (whirling movements) performance, as a Masterpiece of the Intangible Heritage of Humanity in 2005 by UNESCO and 2007 as the International Year of Mevlâna, started an increase in studies about mevlevihanes and a wave of restorations, especially of their semahanes (the large assembly whirling halls where the Mevlevi Ritual Whirling Ceremony was performed). However, due to inadequacies in legal procedures, socio-cultural changes, economic incapacity, negative environmental factors, and faulty repair practices, the studies and applications for the protection of mevlevihanes have not reached the desired level. Within this historical perspective, this study aims to reveal the particular architectural conservation and restoration problems of mevlevihanes and propose solutions for them. Firstly, the categorization and components of mevlevihane architecture was evaluated through its historical process. Secondly, their basic architectural characteristics were explained. Thirdly, by examining recently restored examples like Manisa, Edirne, Bursa, Tokat, Gelibolu, and Çankırı Mevlevihanes, using archival documents, old maps, drawings, photos and reports, building survey method, mevlevihane architectural conservation and restoration application problems were analyzed. Finally, solution suggestions were proposed for the problems that threaten the proper restoration of mevlevihanes. It is hoped that this study will contribute to the preservation of Mevlevihanes which have played an important role in the architectural, cultural heritage of Turkey, and that their authentic values will be properly transmitted to future generations.

Keywords: conservation, cultural heritage, mevlevihane architecture, reastoration

Procedia PDF Downloads 47
354 Inhibition of Mild Steel Corrosion in Hydrochloric Acid Medium Using an Aromatic Hydrazide Derivative

Authors: Preethi Kumari P., Shetty Prakasha, Rao Suma A.

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Mild steel has been widely employed as construction materials for pipe work in the oil and gas production such as down hole tubular, flow lines and transmission pipelines, in chemical and allied industries for handling acids, alkalis and salt solutions due to its excellent mechanical property and low cost. Acid solutions are widely used for removal of undesirable scale and rust in many industrial processes. Among the commercially available acids hydrochloric acid is widely used for pickling, cleaning, de-scaling and acidization of oil process. Mild steel exhibits poor corrosion resistance in presence of hydrochloric acid. The high reactivity of mild steel in presence of hydrochloric acid is due to the soluble nature of ferrous chloride formed and the cementite phase (Fe3C) normally present in the steel is also readily soluble in hydrochloric acid. Pitting attack is also reported to be a major form of corrosion in mild steel in the presence of high concentrations of acids and thereby causing the complete destruction of metal. Hydrogen from acid reacts with the metal surface and makes it brittle and causes cracks, which leads to pitting type of corrosion. The use of chemical inhibitor to minimize the rate of corrosion has been considered to be the first line of defense against corrosion. In spite of long history of corrosion inhibition, a highly efficient and durable inhibitor that can completely protect mild steel in aggressive environment is yet to be realized. It is clear from the literature review that there is ample scope for the development of new organic inhibitors, which can be conveniently synthesized from relatively cheap raw materials and provide good inhibition efficiency with least risk of environmental pollution. The aim of the present work is to evaluate the electrochemical parameters for the corrosion inhibition behavior of an aromatic hydrazide derivative, 4-hydroxy- N '-[(E)-1H-indole-2-ylmethylidene)] benzohydrazide (HIBH) on mild steel in 2M hydrochloric acid using Tafel polarization and electrochemical impedance spectroscopy (EIS) techniques at 30-60 °C. The results showed that inhibition efficiency increased with increase in inhibitor concentration and decreased marginally with increase in temperature. HIBH showed a maximum inhibition efficiency of 95 % at 8×10-4 M concentration at 30 °C. Polarization curves showed that HIBH act as a mixed-type inhibitor. The adsorption of HIBH on mild steel surface obeys the Langmuir adsorption isotherm. The adsorption process of HIBH at the mild steel/hydrochloric acid solution interface followed mixed adsorption with predominantly physisorption at lower temperature and chemisorption at higher temperature. Thermodynamic parameters for the adsorption process and kinetic parameters for the metal dissolution reaction were determined.

Keywords: electrochemical parameters, EIS, mild steel, tafel polarization

Procedia PDF Downloads 310
353 Variability of Physico-Chemical and Carbonate Chemistry of Seawater in Selected Portions of the Central Atlantic Coastline of Ghana

Authors: Robert Kwame Kpaliba, Dennis Kpakpor Adotey, Yaw Serfor-Armah

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Increase in the oceanic carbon dioxide absorbance from the atmosphere due to climate change has led to appreciable change in the chemistry of the oceans. The change in oceanic pH referred to as ocean acidification poses multiple threats and stresses on marine species, biodiversity, goods and services, and livelihoods. Marine ecosystems are continuously threatened by plethora of natural and anthropogenic stressors including carbon dioxide (CO₂) emissions causing a lot of changes which has not been experienced for approximately 60 years. Little has been done in Africa as a whole and Ghana in particular to improve the understanding of the variations of the carbonate chemistry of seawater and the biophysical impacts of ocean acidification on security of seafood, nutrition, climate and environmental change. There is, therefore, the need for regular monitoring of carbonate chemistry of seawater along Ghana’s coastline to generate reliable data to aid marine policy formulation. Samples of seawater were collected thrice every month for a one-year period from five study sites for the various parameters to be analyzed. Analysis of the measured physico-chemical and the carbonate chemistry parameters was done using simple statistics. Correlation test and ANOVA were run on both of the physico-chemical and carbonate chemistry parameters. The carbonate chemistry parameters were measured using computer software programme (CO₂cal v4.0.9) except total alkalinity and pH. The study assessed the variability of seawater carbonate chemistry in selected portions of the Central Atlantic Coastline of Ghana (Tsokomey/Bortianor, Kokrobitey, Gomoa Nyanyanor, Gomoa Fetteh, and Senya Breku landing beaches) over a 1-year period (June 2016–May 2017). For physico-chemical parameters, there was insignificant variation in nitrate (NO₃⁻) (1.62 - 2.3 mg/L), ammonia (NH₃) (1.52 - 2.05 mg/L), and salinity (sal) (34.50 - 34.74 ppt). Carbonate chemistry parameters for all the five study sites showed significant variation: partial pressure of carbon dioxide (pCO₂) (414.08-715.5 µmol/kg), carbonate ion (CO₃²⁻) (115-157.92 µmol/kg), pH (7.9-8.12), total alkalinity (TA) (1711.8-1986 µmol/kg), total carbon dioxide (TCO₂) (1512.1 - 1792 µmol/kg), dissolved carbon dioxide (CO₂aq) (10.97-18.92 µmol/kg), Revelle Factor (RF) (9.62-11.84), aragonite (ΩAr) (0.75-1.48) and calcite (ΩCa) (1.08-2.14). The study revealed that the partial pressure of carbon dioxide and temperature did not have a significant effect on each other (r² = 0.31) (p-value = 0.0717). There was an appreciable effect of pH on dissolved carbon dioxide (r² = 0.921) (p-value = 0.0000). The variation between total alkalinity and dissolved carbon dioxide was appreciable (r² = 0.731) (p-value = 0.0008). There was a significant correlation between total carbon dioxide and dissolved carbon dioxide (r² = 0.852) (p-value = 0.0000). Revelle factor correlated strongly with dissolved carbon dioxide (r² = 0.982) (p-value = 0.0000). Partial pressure of carbon dioxide corresponds strongly with atmospheric carbon dioxide (r² = 0.9999) (p-value = 0.00000).

Keywords: carbonate chemistry, seawater, central atlantic coastline, Ghana, ocean acidification

Procedia PDF Downloads 529
352 Rest Behavior and Restoration: Searching for Patterns through a Textual Analysis

Authors: Sandra Christina Gressler

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Resting is essentially the physical and mental relaxation. So, can behaviors that go beyond the merely physical relaxation to some extent be understood as a behavior of restoration? Studies on restorative environments emphasize the physical, mental and social benefits that some environments can provide and suggest that activities in natural environments reduce the stress of daily lives, promoting recovery against the daily wear. These studies, though specific in their results, do not unify the different possibilities of restoration. Considering the importance of restorative environments by promoting well-being, this research aims to verify the applicability of the theory on restorative environments in a Brazilian context, inquiring about the environment/behavior of rest. The research sought to achieve its goals by; a) identifying daily ways of how participants interact/connect with nature; b) identifying the resting environments/behavior; c) verifying if rest strategies match the restorative environments suggested by restorative studies; and d) verifying different rest strategies related to time. Workers from different companies in which certain functions require focused attention, and high school students from different schools, participated in this study. An interview was used to collect data and information. The data obtained were compared with studies of attention restoration theory and stress recovery. The collected data were analyzed through the basic descriptive inductive statistics and the use of the software ALCESTE® (Analyse Lexicale par Contexte d'un Ensemble de Segments de Texte). The open questions investigate perception of nature on a daily basis – analysis using ALCESTE; rest periods – daily, weekends and holidays – analysis using ALCESTE with tri-croisé; and resting environments and activities – analysis using a simple descriptive statistics. According to the results, environments with natural characteristics that are compatible with personal desires (physical aspects and distance) and residential environments when they fulfill the characteristics of refuge, safety, and self-expression, characteristics of primary territory, meet the requirements of restoration. Analyzes suggest that the perception of nature has a wide range that goes beyond the objects nearby and possible to be touched, as well as observation and contemplation of details. The restoration processes described in the studies of attention restoration theory occur gradually (hierarchically), starting with being away, following compatibility, fascination, and extent. They are also associated with the time that is available for rest. The relation between rest behaviors and the bio-demographic characteristics of the participants are noted. It reinforces, in studies of restoration, the need to insert not only investigations regarding the physical characteristics of the environment but also behavior, social relationship, subjective reactions, distance and time available. The complexity of the theme indicates the necessity for multimethod studies. Practical contributions provide subsidies for developing strategies to promote the welfare of the population.

Keywords: attention restoration theory, environmental psychology, rest behavior, restorative environments

Procedia PDF Downloads 158
351 Using Google Distance Matrix Application Programming Interface to Reveal and Handle Urban Road Congestion Hot Spots: A Case Study from Budapest

Authors: Peter Baji

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In recent years, a growing body of literature emphasizes the increasingly negative impacts of urban road congestion in the everyday life of citizens. Although there are different responses from the public sector to decrease traffic congestion in urban regions, the most effective public intervention is using congestion charges. Because travel is an economic asset, its consumption can be controlled by extra taxes or prices effectively, but this demand-side intervention is often unpopular. Measuring traffic flows with the help of different methods has a long history in transport sciences, but until recently, there was not enough sufficient data for evaluating road traffic flow patterns on the scale of an entire road system of a larger urban area. European cities (e.g., London, Stockholm, Milan), in which congestion charges have already been introduced, designated a particular zone in their downtown for paying, but it protects only the users and inhabitants of the CBD (Central Business District) area. Through the use of Google Maps data as a resource for revealing urban road traffic flow patterns, this paper aims to provide a solution for a fairer and smarter congestion pricing method in cities. The case study area of the research contains three bordering districts of Budapest which are linked by one main road. The first district (5th) is the original downtown that is affected by the congestion charge plans of the city. The second district (13th) lies in the transition zone, and it has recently been transformed into a new CBD containing the biggest office zone in Budapest. The third district (4th) is a mainly residential type of area on the outskirts of the city. The raw data of the research was collected with the help of Google’s Distance Matrix API (Application Programming Interface) which provides future estimated traffic data via travel times between freely fixed coordinate pairs. From the difference of free flow and congested travel time data, the daily congestion patterns and hot spots are detectable in all measured roads within the area. The results suggest that the distribution of congestion peak times and hot spots are uneven in the examined area; however, there are frequently congested areas which lie outside the downtown and their inhabitants also need some protection. The conclusion of this case study is that cities can develop a real-time and place-based congestion charge system that forces car users to avoid frequently congested roads by changing their routes or travel modes. This would be a fairer solution for decreasing the negative environmental effects of the urban road transportation instead of protecting a very limited downtown area.

Keywords: Budapest, congestion charge, distance matrix API, application programming interface, pilot study

Procedia PDF Downloads 172
350 Integrating High-Performance Transport Modes into Transport Networks: A Multidimensional Impact Analysis

Authors: Sarah Pfoser, Lisa-Maria Putz, Thomas Berger

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In the EU, the transport sector accounts for roughly one fourth of the total greenhouse gas emissions. In fact, the transport sector is one of the main contributors of greenhouse gas emissions. Climate protection targets aim to reduce the negative effects of greenhouse gas emissions (e.g. climate change, global warming) worldwide. Achieving a modal shift to foster environmentally friendly modes of transport such as rail and inland waterways is an important strategy to fulfill the climate protection targets. The present paper goes beyond these conventional transport modes and reflects upon currently emerging high-performance transport modes that yield the potential of complementing future transport systems in an efficient way. It will be defined which properties describe high-performance transport modes, which types of technology are included and what is their potential to contribute to a sustainable future transport network. The first step of this paper is to compile state-of-the-art information about high-performance transport modes to find out which technologies are currently emerging. A multidimensional impact analysis will be conducted afterwards to evaluate which of the technologies is most promising. This analysis will be performed from a spatial, social, economic and environmental perspective. Frequently used instruments such as cost-benefit analysis and SWOT analysis will be applied for the multidimensional assessment. The estimations for the analysis will be derived based on desktop research and discussions in an interdisciplinary team of researchers. For the purpose of this work, high-performance transport modes are characterized as transport modes with very fast and very high throughput connections that could act as efficient extension to the existing transport network. The recently proposed hyperloop system represents a potential high-performance transport mode which might be an innovative supplement for the current transport networks. The idea of hyperloops is that persons and freight are shipped in a tube at more than airline speed. Another innovative technology consists in drones for freight transport. Amazon already tests drones for their parcel shipments, they aim for delivery times of 30 minutes. Drones can, therefore, be considered as high-performance transport modes as well. The Trans-European Transport Networks program (TEN-T) addresses the expansion of transport grids in Europe and also includes high speed rail connections to better connect important European cities. These services should increase competitiveness of rail and are intended to replace aviation, which is known to be a polluting transport mode. In this sense, the integration of high-performance transport modes as described above facilitates the objectives of the TEN-T program. The results of the multidimensional impact analysis will reveal potential future effects of the integration of high-performance modes into transport networks. Building on that, a recommendation on the following (research) steps can be given which are necessary to ensure the most efficient implementation and integration processes.

Keywords: drones, future transport networks, high performance transport modes, hyperloops, impact analysis

Procedia PDF Downloads 305
349 The Effect of TiO₂ Nanoparticles on Zebrafish Embryos

Authors: Elena Maria Scalisi

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Currently, photodegradation by nanoparticles (NPs) is a common solution for wastewater treatment. Nanoparticles are efficient for removing organic and inorganic pollutants, heavy metals from wastewater and killing microorganisms through environmentally friendly. In this context, the major representative of photocatalytic technology for industrial wastewater treatment are TiO₂ nanoparticles (TiO₂-NPs). TiO₂-NPs have a strong catalytic activity that depends to their physicochemical properties. Thanks to their small size (between 1-100 nm), nanoparticles occupy less volume, then their surface area increases. The increase in the surface-to-volume ratio results in the increase of the particle surface energy, which improve their reactivity potential. However, these unique properties represent risks to the ecosystems and organisms when unintentionally TiO₂-NPs are release into the environment and absorbed by living organisms. Several studies confirm that there is a high level of interest concerning the safety of TiO₂-NPs in the aquatic environment, furthermore, ecotoxicological tools are useful to correctly evaluate their toxicity. In the current study, we aimed to characterize potential toxic effects of TiO₂-NP suspension to zebrafish during embryo-larval stages to evaluate parameters such as survival rates, malformation, hatching, the overall length of the larvae heartbeat, and biochemical biomarkers that reflect the acute toxicity and sublethal effects of TiO₂-NPs. Zebrafish embryos were exposed to titanium dioxide nanoparticles (TiO₂-NPs at 1mg/L, 2mg/L, and 4mg/L) from fertilization to the free swimming stage (144hpf). Every day, we recorded the toxicological endpoints, moreover, immunohistochemical analysis has been performed at the end of the exposure. In particular, we have evaluate the expression of the following biomarkers: Heat Shock Protein 70 (HSP70), Poly ADP-Ribose Polymerase-1 (PARP-1), Metallothioneins (MTs). Our results have shown that hatch ability, survival, and malformation rate were not affected by TiO₂ NPs at these exposure levels. However, TiO₂-NPs caused an increase of heartbeat and reduction of body length; at the same time, TiO₂-NPs have inducted the production of ROS and the expression of oxidative stress biomarkers HSP70 and PARP-1. Hight positivity for PARP-1 at all concentration tested was observed. As regards MT, positivity was found in the expression of this biomarker in the whole body of the embryo, with the exception of the end of the tail. Metallothioneins (MT) are biomarkers widely used in environmental monitoring programs for aquatic creatures. At the light of our results i.e. no death until the end of the experiment (144hpf), no malformation and expression of the biomarkers mentioned, it is evident that zebrafish larvae with their natural detoxification pathways are able to resist the presence of toxic substances and then they can tolerate the presence of metal concentrations. However, an excessive oxidative state can compromise cell function, therefore the uncontrolled release of nanoparticles into the environment is severe and must be constantly monitored.

Keywords: nanoparticles, embryo zebrafish, HSP70, PARP-1

Procedia PDF Downloads 115
348 The Effect of Vibration Amplitude on Tissue Temperature and Lesion Size When Using a Vibrating Cardiac Catheter

Authors: Kaihong Yu, Tetsui Yamashita, Shigeaki Shingyochi, Kazuo Matsumoto, Makoto Ohta

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During cardiac ablation, high power delivery for deeper lesion formation is limited by electrode-tissue interface overheating which can cause serious complications such as thrombus. To prevent this overheating, temperature control and open irrigation are often used. In temperature control, radiofrequency generator is adjusted to deliver the maximum output power, which maintains the electrode temperature at a target temperature (commonly 55°C or 60°C). Then the electrode-tissue interface temperature is also limited. The electrode temperature is a result of heating from the contacted tissue and cooling from the surrounding blood. Because the cooling from blood is decreased under conditions of low blood flow, the generator needs to decrease the output power. Thus, temperature control cannot deliver high power under conditions of low blood flow. In open irrigation, saline in room temperature is flushed through the holes arranged in the electrode. The electrode-tissue interface is cooled by the sufficient environmental cooling. And high power delivery can also be done under conditions of low blood flow. However, a large amount of saline infusions (approximately 1500 ml) during irrigation can cause other serious complication. When open irrigation cannot be used under conditions of low blood flow, a new overheating prevention may be required. The authors have proposed a new electrode cooling method by making the catheter vibrating. The previous work has introduced that the vibration can make a cooling effect on electrode, which may result form that the vibration could increase the flow velocity around the catheter. The previous work has also proved that increasing vibration frequency can increase the cooling by vibration. However, the effect of the vibration amplitude is still unknown. Thus, the present study investigated the effect of vibration amplitude on tissue temperature and lesion size. An agar phantom model was used as a tissue-equivalent material for measuring tissue temperature. Thermocouples were inserted into the agar to measure the internal temperature. Porcine myocardium was used for lesion size measurement. A normal ablation catheter was set perpendicular to the tissue (agar or porcine myocardium) with 10 gf contact force in 37°C saline without flow. Vibration amplitude of ± 0.5, ± 0.75, and ± 1.0 mm with a constant frequency (31 Hz or 63) was used. A temperature control protocol (45°C for agar phantom, 60°C for porcine myocardium) was used for the radiofrequency applications. The larger amplitude shows the larger lesion sizes. And the higher tissue temperatures in agar phantom are also shown with the higher amplitude. With a same frequency, the larger amplitude has the higher vibrating speed. And the higher vibrating speed will increase the flow velocity around the electrode more, which leads to a larger electrode temperature decrease. To maintain the electrode at the target temperature, ablator has to increase the output power. With the higher output power in the same duration, the released energy also increases. Consequently, the tissue temperature will be increased and lead to larger lesion sizes.

Keywords: cardiac ablation, electrode cooling, lesion size, tissue temperature

Procedia PDF Downloads 351
347 Testing Nitrogen and Iron Based Compounds as an Environmentally Safer Alternative to Control Broadleaf Weeds in Turf

Authors: Simran Gill, Samuel Bartels

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Turfgrass is an important component of urban and rural lawns and landscapes. However, broadleaf weeds such as dandelions (Taraxacum officinale) and white clovers (Trifolium repens) pose major challenges to the health and aesthetics of turfgrass fields. Chemical weed control methods, such as 2,4-D weedicides, have been widely deployed; however, their safety and environmental impacts are often debated. Alternative, environmentally friendly control methods have been considered, but experimental tests for their effectiveness have been limited. This study investigates the use and effectiveness of nitrogen and iron compounds as nutrient management methods of weed control. In a two-phase experiment, the first conducted on a blend of cool season turfgrasses in plastic containers, the blend included Perennial ryegrass (Lolium perenne), Kentucky bluegrass (Poa pratensis) and Creeping red fescue (Festuca rubra) grown under controlled conditions in the greenhouse, involved the application of different combinations of nitrogen (urea and ammonium sulphate) and iron (chelated iron and iron sulphate) compounds and their combinations (urea × chelated iron, urea × iron sulphate, ammonium sulphate × chelated iron, ammonium sulphate × iron sulphate) contrasted with chemical 2, 4-D weedicide and a control (no application) treatment. There were three replicates of each of the treatments, resulting in a total of 30 treatment combinations. The parameters assessed during weekly data collection included a visual quality rating of weeds (nominal scale of 0-9), number of leaves, longest leaf span, number of weeds, chlorophyll fluorescence of grass, the visual quality rating of grass (0-9), and the weight of dried grass clippings. The results drawn from the experiment conducted over the period of 12 weeks, with three applications each at an interval of every 4 weeks, stated that the combination of ammonium sulphate and iron sulphate appeared to be most effective in halting the growth and establishment of dandelions and clovers while it also improved turf health. The second phase of the experiment, which involved the ammonium sulphate × iron sulphate, weedicide, and control treatments, was conducted outdoors on already established perennial turf with weeds under natural field conditions. After 12 weeks of observation, the results were comparable among the treatments in terms of weed control, but the ammonium sulphate × iron sulphate treatment fared much better in terms of the improved visual quality of the turf and other quality ratings. Preliminary results from these experiments thus suggest that nutrient management based on nitrogen and iron compounds could be a useful environmentally friendly alternative for controlling broadleaf weeds and improving the health and quality of turfgrass.

Keywords: broadleaf weeds, nitrogen, iron, turfgrass

Procedia PDF Downloads 40
346 Operation '1 Household Dry Toilet for Planting 20 Fruit Trees and/or Acacias on Cropland': Strategy for Promoting Adoption of Well-Managed Agroforestry Systems and Prevent Streaming and Soil Erosion

Authors: Stanis Koko Nyalongomo, Benjamin Mputela Bankanza, Moise Kisempa Mahungudi

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Several areas in the Democratic Republic of Congo (DRC) experience serious problems of streaming and soil erosion. Erosion leads to degradation of soil health, and the three main causative factors of similar importance are deforestation, overgrazing, and land agricultural mismanagement. Degradation of soil health leads to a decrease in agricultural productivity and carbon dioxide (CO₂), and other greenhouse gas emissions. Agricultural productivity low, and sanitation-related diseases are a concern of a majority of DRC rural people -whose main livelihoods are conventional smallholder agriculture- due to degradation of agricultural soil health and prevalence of inappropriate sanitation in rural areas. Land management practices that increase soil carbon stocks on agricultural lands with practices including conservation agriculture and agroforestry do not only limit CO₂ emissions but also help prevent erosion while enhancing soil health and productivity. Promotion to adopt sustainable land management practices, especially conversion to well-managed agroforestry practices, is a necessity. This needs to be accompanied by incentives. Methods that incite smallholders to adopt practices that increase carbon stocks in agricultural lands and enhance soil health and productivity for social, economic, and environmental benefits, and give them the ability to get and use household dry toilets -included activities to inform and raise smallholder households awareness on the conversion of croplands to well-managed agroforestry systems through planting at least 20 fruit trees and/or acacias, soil carbon and practices that sequester it in soil and ecological sanitation; and offer smallholders technique and material supports and incentives under the form of dry toilets constructed for free for well-managed agroforestry implementation- were carried out to address problems of soil erosion as well as agricultural productivity and sanitation-related diseases. In 2018 and 2019, 19 of 23 targeted smallholder households expressed their satisfaction and converted their croplands to agroforestry through planting 374 trees, and each gotten 1 dry toilet constructed for free. Their neighbors expressed a willingness to participate in the project. Conversion to well-managed agroforestry practices offers many advantages to both farmers and the environment. The strategy of offering smallholders incentives for soil-friendly agricultural practices, especially well-managed agroforestry, is one of the solutions to prevent soil erosion. DRC rural people whose majority are smallholder households, need to be able to get and use dry toilets. So, dry toilets could be offered like incentives for well-managed agroforestry practices. Given the many advantages agroforestry and dry toilet can offer, recommendations are made for funding organizations to support such projects that promote the adoption of soil health practices.

Keywords: agroforestry, croplands, soil carbon, soil health

Procedia PDF Downloads 99
345 Impact of Sunflower Oil Supplemented Diet on Performance and Hematological Stress Indicators of Growing-Finishing Pigs Exposed to Hot Environment

Authors: Angela Cristina Da F. De Oliveira, Salma E. Asmar, Norbert P. Battlori, Yaz Vera, Uriel R. Valencia, Tâmara Duarte Borges, Antoni D. Bueno, Leandro Batista Costa

Abstract:

As homeothermic animals, pigs manifest maximum performance when kept at comfortable temperature levels, represented by a limit where thermoregulatory processes are minimal (18 - 20°C). In a stress situation where it will have a higher energy demand for thermal maintenance, the energy contribution to the productive functions will be reduced, generating health imbalances, drop in productive rates and welfare problems. The hypothesis of this project is that 5% starch replacement per 5% sunflower oil (SO), in growing and finishing pig’s diet (Iberic x Duroc), is effective as a nutritional strategy to reduce the negative impacts of thermal stress on performance and animal welfare. Seventy-two crossbred males (51± 6,29 kg body weight- BW) were housed according to the initial BW, in climate-controlled rooms, in collective pens, and exposed to heat stress conditions (30 - 32°C; 35% to 50% humidity). The experiment lasted 90 days, and it was carried out in a randomized block design, in a 2 x 2 factorial, composed of two diets (starch or sunflower oil (with or without) and two feed intake management (ad libitum and restriction). The treatments studied were: 1) control diet (5% starch x 0% SO) with ad libitum intake (n = 18); 2) SO diet (replacement of 5% of starch per 5% SO) with ad libitum intake (n = 18); 3) control diet with restriction feed intake (n = 18); or 4) SO diet with restriction feed intake (n = 18). Feed was provided in two phases, 50–100 Kg BW for growing and 100-140 Kg BW for finishing period, respectively. Hematological, biochemical and growth performance parameters were evaluated on all animals at the beginning of the environmental treatment, on the transition of feed (growing to finishing) and in the final of experiment. After the experimental period, when animals reached a live weight of 130-140 kg, they were slaughtered by carbon dioxide (CO2) stunning. Data have shown for the growing phase no statistical interaction between diet (control x SO) and management feed intake (ad libitum x restriction) on animal performance. At finishing phase, pigs fed with SO diet with restriction feed intake had the same average daily gain (ADG) compared with pigs in control diet with ad libitum feed intake. Furthermore, animals fed with the same diet (SO), presented a better feed gain (p < 0,05) due to feed intake reduce (p < 0,05) when compared with control group. To hematological and biochemical parameters, animals under heat stress had an increase in hematocrit, corpuscular volume, urea concentration, creatinine, calcium, alanine aminotransferase and aspartate aminotransferase (p < 0,05) when compared with the beginning of experiment. These parameters were efficient to characterize the heat stress, although the experimental treatments were not able to reduce the hematological and biochemical stress indicators. In addition, the inclusion of SO on pig diets improve feed gain in pigs at finishing phase, even with restriction feed intake.

Keywords: hematological, performance, pigs, welfare

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344 Survey of the Literacy by Radio Project as an Innovation in Literacy Promotion in Nigeria

Authors: Stella Chioma Nwizu

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The National Commission for Adult and Non Formal Education (NMEC) in Nigeria is charged with the reduction of illiteracy rate through the development, monitoring, and supervision of literacy programmes in Nigeria. In spite of various efforts by NMEC to reduce illiteracy, literature still shows that the illiteracy rate is still high. According to NMEC/UNICEF, about 60 million Nigerians are non-literate, and nearly two thirds of them are women. This situation forced the government to search for innovative and better approaches to literacy promotion and delivery. The literacy by radio project was adopted as an innovative intervention to literacy delivery in Nigeria because the radio is the cheapest and most easily affordable medium for non-literates. The project aimed at widening access to literacy programmes for the non-literate marginalized and disadvantaged groups in Nigeria by taking literacy programmes to their door steps. The literacy by radio has worked perfectly well in non-literacy reduction in Cuba. This innovative intervention of literacy by radio is anchored on the diffusion of innovation theory by Rogers. The literacy by radio has been going on for fifteen years and the efficacy and contributions of this innovation need to be investigated. Thus, the purpose of this research is to review the contributions of the literacy by radio in Nigeria. The researcher adopted the survey research design for the study. The population for the study consisted of 2,706 participants and 47 facilitators of the literacy by radio programme in the 10 pilot states in Nigeria. A sample of four states made up of 302 participants and eight facilitators were used for the study. Information was collected through Focus Group Discussion (FGD), interviews and content analysis of official documents. The data were analysed qualitatively to review the contributions of literacy by radio project and determine the efficacy of this innovative approach in facilitating literacy in Nigeria. Results from the field experience showed, among others, that more non-literates have better access to literacy programmes through this innovative approach. The pilot project was 88% successful; not less than 2,110 adults were made literate through the literacy by radio project in 2017. However, lack of enthusiasm and commitment on the part of the technical committee and facilitators due to non-payment of honorarium, poor signals from radio stations, interruption of lectures with adverts, low community involvement in decision making in the project are challenges to the success rate of the project. The researcher acknowledges the need to customize all materials and broadcasts in all the dialects of the participants and the inclusion of more civil rights, environmental protection and agricultural skills into the project. The study recommends among others, improved and timely funding of the project by the Federal Government to enable NMEC to fulfill her obligations towards the greater success of the programme, setting up of independent radio stations for airing the programmes and proper monitoring and evaluation of the project by NMEC and State Agencies for greater effectiveness. In an era of the knowledge-driven economy, no one should be allowed to get saddled with the weight of illiteracy.

Keywords: innovative approach, literacy, project, radio, survey

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343 Algal/Bacterial Membrane Bioreactor for Bioremediation of Chemical Industrial Wastewater Containing 1,4 Dioxane

Authors: Ahmed Tawfik

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Oxidation of 1,4 dioxane produces metabolites by-products involving glycolaldehyde and acids that have geno- and cytotoxicity impact on microbial degradation. Thereby, the incorporation of algae with bacteria in the treatment system would eliminate and overcome the accumulation of metabolites that are utilized as a carbon source for the build-up of biomass. Therefore, the aim of the present study is to assess the potential of algae/bacteria-based membrane bioreactor (AB-MBR) for biodegradation of 1,4 dioxane-rich wastewater at a high imposed loading rate. Three identical reactors, i.e., AB-MBR1, AB-MBR2, and AB-MBR3, were operated in parallel at 1,4 dioxane loading rates of 641.7, 320.9, and 160.4 mg/L. d., and HRTs of 6.0, 12 and 24 h. respectively. The AB-MBR1 achieved 1,4 dioxane removal rate of 263.7 mg/L.d., where the residual value in the treated effluent amounted to 94.4±22.9 mg/L. Reducing the 1,4 dioxane loading rate (LR) to 320.9 mg/L.d in the AB-MBR2 maximized the removal rate efficiency of 265.9 mg/L.d., with a removal efficiency of 82.8±3.2%. The minimum value of 1,4 dioxane of 17.3±1.8 mg/L in the treated effluent of AB-MBR3 was obtained at an HRT of 24.0 h and loading rate of 160.4 mg/L.d. The mechanism of 1,4 dioxane degradation in AB-MBR was a combination of volatilization (8.03±0.6%), UV oxidation (14.1±0.9%), microbial biodegradation (49.1±3.9%) and absorption/uptake and assimilation by algae (28.8±2.%). Further, the Thioclava, Afipia, and Mycobacterium genera oxidized and produced the required enzymes for hydrolysis and cleavage of the dioxane ring into 2-hydroxy-1,4 dioxane. Moreover, the fungi, i.e., Basidiomycota and Cryptomycota, played a big role in the degradation of the 1,4 dioxane into 2-hydroxy-1,4 dioxane. Xanthobacter and Mesorhizobium were involved in the metabolism process by secreting alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), and glycolate oxidase. Bacteria and fungi produced dehydrogenase (DH) for the transformation of 2-hydroxy-1,4 dioxane into 2-hydroxy-ethoxyacetaldehyde. The latter is converted into Ethylene glycol by Aldehyde hydrogenase (ALDH). Ethylene glycol is oxidized into acids using Alcohol hydrogenase (ADH). The Diatomea, Chlorophyta, and Streptophyta utilize the metabolites for biomass assimilation and produce the required oxygen for further oxidation of the dioxane and its metabolites by-products of bacteria and fungi. The major portion of metabolites (ethylene glycol, glycolic acid, and oxalic acid were removed due to uptake and absorption by algae (43±4.3%), followed by adsorption (18.4±0.9%). The volatilization and UV oxidation contribution for the degradation of metabolites were 8.7±0.7% and 12.3±0.8%, respectively. The capabilities of genera Defluviimonas, Thioclava, Luteolibacter, and Afipia. The genera of Defluviimonas, Thioclava, Luteolibacter, and Mycobacterium were grown under a high 1,4 dioxane LR of 641.7 mg/L.d. The Chlorophyta (4.1-43.6%), Streptophyta (2.5-21.7%), and Diatomea (0.8-1.4%) phyla were dominant for degradation of 1,4 dioxane. The results of this study strongly demonstrated that the bioremediation and bioaugmentation process can safely remove 1,4 dioxane from industrial wastewater while minimizing environmental concerns and reducing economic costs.

Keywords: wastewater, membrane bioreactor, bacterial community, algal community

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342 Precursor Synthesis of Carbon Materials with Different Aggregates Morphologies

Authors: Nikolai A. Khlebnikov, Vladimir N. Krasilnikov, Evgenii V. Polyakov, Anastasia A. Maltceva

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Carbon materials with advanced surfaces are widely used both in modern industry and in environmental protection. The physical-chemical nature of these materials is determined by the morphology of primary atomic and molecular carbon structures, which are the basis for synthesizing the following materials: zero-dimensional (fullerenes), one-dimensional (fiber, tubes), two-dimensional (graphene) carbon nanostructures, three-dimensional (multi-layer graphene, graphite, foams) with unique physical-chemical and functional properties. Experience shows that the microscopic morphological level is the basis for the creation of the next mesoscopic morphological level. The dependence of the morphology on the chemical way and process prehistory (crystallization, colloids formation, liquid crystal state and other) is the peculiarity of the last called level. These factors determine the consumer properties of carbon materials, such as specific surface area, porosity, chemical resistance in corrosive environments, catalytic and adsorption activities. Based on the developed ideology of thin precursor synthesis, the authors discuss one of the approaches of the porosity control of carbon-containing materials with a given aggregates morphology. The low-temperature thermolysis of precursors in a gas environment of a given composition is the basis of the above-mentioned idea. The processes of carbothermic precursor synthesis of two different compounds: tungsten carbide WC:nC and zinc oxide ZnO:nC containing an impurity phase in the form of free carbon were selected as subjects of the research. In the first case, the transition metal (tungsten) forming carbides was the object of the synthesis. In the second case, there was selected zinc that does not form carbides. The synthesis of both kinds of transition metals compounds was conducted by the method of precursor carbothermic synthesis from the organic solution. ZnO:nC composites were obtained by thermolysis of succinate Zn(OO(CH2)2OO), formate glycolate Zn(HCOO)(OCH2CH2O)1/2, glycerolate Zn(OCH2CHOCH2OH), and tartrate Zn(OOCCH(OH)CH(OH)COO). WC:nC composite was synthesized from ammonium paratungstate and glycerol. In all cases, carbon structures that are specific for diamond- like carbon forms appeared on the surface of WC and ZnO particles after the heat treatment. Tungsten carbide and zinc oxide were removed from the composites by selective chemical dissolution preserving the amorphous carbon phase. This work presents the results of investigating WC:nC and ZnO:nC composites and carbon nanopowders with tubular, tape, plate and onion morphologies of aggregates that are separated by chemical dissolution of WC and ZnO from the composites by the following methods: SEM, TEM, XPA, Raman spectroscopy, and BET. The connection between the carbon morphology under the conditions of synthesis and chemical nature of the precursor and the possibility of regulation of the morphology with the specific surface area up to 1700-2000 m2/g of carbon-structured materials are discussed.

Keywords: carbon morphology, composite materials, precursor synthesis, tungsten carbide, zinc oxide

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341 Metabolomics Fingerprinting Analysis of Melastoma malabathricum L. Leaf of Geographical Variation Using HPLC-DAD Combined with Chemometric Tools

Authors: Dian Mayasari, Yosi Bayu Murti, Sylvia Utami Tunjung Pratiwi, Sudarsono

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Melastoma malabathricum L. is an Indo-Pacific herb that has been traditionally used to treat several ailments such as wounds, dysentery, diarrhea, toothache, and diabetes. This plant is common across tropical Indo-Pacific archipelagos and is tolerant of a range of soils, from low-lying areas subject to saltwater inundation to the salt-free conditions of mountain slopes. How the soil and environmental variation influences secondary metabolite production in the herb, and an understanding of the plant’s utility as traditional medicine, remain largely unknown and unexplored. The objective of this study is to evaluate the variability of the metabolic profiles of M. malabathricum L. across its geographic distribution. By employing high-performance liquid chromatography-diode array detector (HPLC-DAD), a highly established, simple, sensitive, and reliable method was employed for establishing the chemical fingerprints of 72 samples of M. malabathricum L. leaves from various geographical locations in Indonesia. Specimens collected from six terrestrial and archipelago regions of Indonesia were analyzed by HPLC to generate chromatogram peak profiles that could be compared across each region. Data corresponding to the common peak areas of HPLC chromatographic fingerprint were analyzed by hierarchical component analysis (HCA) and principal component analysis (PCA) to extract information on the most significant variables contributing to characterization and classification of analyzed samples data. Principal component values were identified as PC1 and PC2 with 41.14% and 19.32%, respectively. Based on variety and origin, the high-performance liquid chromatography method validated the chemical fingerprint results used to screen the in vitro antioxidant activity of M. malabathricum L. The result shows that the developed method has potential values for the quality of similar M. malabathrium L. samples. These findings provide a pathway for the development and utilization of references for the identification of M. malabathricum L. Our results indicate the importance of considering geographic distribution during field-collection efforts as they demonstrate regional metabolic variation in secondary metabolites of M. malabathricum L., as illustrated by HPLC chromatogram peaks and their antioxidant activities. The results also confirm the utility of this simple approach to a rapid evaluation of metabolic variation between plants and their potential ethnobotanical properties, potentially due to the environments from whence they were collected. This information will facilitate the optimization of growth conditions to suit particular medicinal qualities.

Keywords: fingerprint, high performance liquid chromatography, Melastoma malabathricum l., metabolic profiles, principal component analysis

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340 The Effects of Heavy Metal and Aromatic Hydrocarbon Pollution on Bees

Authors: Katarzyna Zięba, Hajnalka Szentgyörgyi, Paweł Miśkowiec, Agnieszka Moos-Matysik

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Bees are effective pollinators of plants using by humans. However, there is a concern about the fate different species due to their recently decline. Pollution of the environment is described in the literature as one of the causes of this phenomenon. Due to human activities, heavy metals and aromatic hydrocarbons can occur in bee organisms in high concentrations. The presented study aims to provide information on how pollution affects bee quality, taking into account, also the biological differences between various groups of bees. Understanding the consequences of environmental pollution on bees can help to create and promote bee friendly habitats and actions. The analyses were carried out using two contamination gradients with 5 sites on each. The first, mainly heavy metal polluted gradient is stretching approx. 30km from the Bukowno Zinc smelter near Olkusz in the Lesser Poland Voivodship, to the north. The second cuts through the agglomeration of Kraków up to the southern borders of the Ojców National Park. The gradient near Olkusz is a well-described pollution gradient contaminated mainly by zinc, lead, and cadmium. The second gradient cut through the agglomeration of Kraków and end below the Ojców National Park. On each gradient, two bee species were installed: red mason bees (Osmia bicornis) and honey bees (Apis mellifera). Red mason bee is a polylectic, solitary bee species, widely distributed in Poland. Honey bees are a highly social species of bees, with clearly defined casts and roles in the colony. Before installing the bees in the field, samples of imagos of red mason bees and samples of pollen and imagos from each honey bee colony were analysed for zinc, lead cadmium, polycyclic and monocyclic hydrocarbons levels. After collecting the bees from the field, samples of bees and pollen samples for each site were prepared for heavy metal, monocyclic hydrocarbon, and polycyclic hydrocarbon analysis. Analyses of aromatic hydrocarbons were performed with gas chromatography coupled with a headspace sampler (HP 7694E) and mass spectrometer (MS) as detector. Monocyclic compounds were injected into column with headspace sampler while polycyclic ones with manual injector (after solid-liquid extraction with hexane). The heavy metal content (zinc, lead and cadmium) was assessed with flame atomic absorption spectroscopy (FAAS AAnalyst 300 Perkin Elmer spectrometer) according to the methods for honey and bee products described in the literature. Pollution levels found in bee bodies and imago body masses in both species, and proportion of sex in case of red mason bees were correlated with pollution levels found in pollen for each site and colony or trap nest. An attempt to pinpoint the most important form of contamination regarding bee health was also be undertaken based on the achieved results.

Keywords: heavy metals, aromatic hydrocarbons, bees, pollution

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