Search results for: environmental concern

Authors: V. H. Nguyen, A. Castalone, C. Jamieson, M. Gummert

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Rice straw is an abundant biomass resource in Asian countries that can be used for bioenergy. In continuously flooded rice fields, it can be removed without reducing the levels of soil organic matter. One suitable bioenergy technology is anaerobic digestion (AD), but it needs to be further verified using rice straw as a feedstock. For this study, a batch AD system was developed using rice straw and cow dung. It is low cost, farm scale, with the batch capacity ranging from 5 kg to 200 kg of straw mixed with 10% of cow dung. The net energy balance obtained was from 3000 to 4000 MJ per ton of straw input at 15-18% moisture content. Net output energy obtained from biogas and digestate ranged from 4000 to 5000 MJ per ton of straw. This indicates AD as a potential solution for converting rice straw from a waste to a clean fuel, reducing the environmental footprint caused by current disposal practices.

Keywords: rice straw, anaerobic digestion, biogas, bioenergy

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Authors: S. Dhib, S. A. Addouche, T. Loukil, A. Elmhamedi

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In this paper, a reverse supply chain network is investigated for a decision making. This decision is surrounded by complex flows of returned products, due to the increasing quantity, the type of returned products and the variety of recovery option products (reuse, recycling, and refurbishment). The most important problem in the reverse logistic network (RLN) is to orient returned products to the suitable type of recovery option. However, returned products orientations from collect sources to the recovery disposition have not well considered in performance model. In this study, we propose a performance model for designing a network configuration on reverse logistics. Conceptual and analytical models are developed with taking into account operational, economic and environmental factors on designing network.

Keywords: reverse logistics, network design, performance model, open loop configuration

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Authors: Ankita Jadon, Sidi Souvi, Nathalie Girault, Denis Petitprez

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Safety requirements for Generation IV nuclear reactor designs, especially the new generation sodium-cooled fast reactors (SFR) require a risk-informed approach to model severe accidents (SA) and their consequences in case of outside release. In SFRs, aerosols are produced during a core disruptive accident when primary system sodium is ejected into the containment and burn in contact with the air; producing sodium aerosols. One of the key aspects of safety evaluation is the in-containment sodium aerosol behavior and their interaction with fission products. The study of the effects of sodium fires is essential for safety evaluation as the fire can both thermally damage the containment vessel and cause an overpressurization risk. Besides, during the fire, airborne fission product first dissolved in the primary sodium can be aerosolized or, as it can be the case for fission products, released under the gaseous form. The objective of this work is to study the interactions between sodium aerosols and fission products (Iodine, toxic and volatile, being the primary concern). Sodium fires resulting from an SA would produce aerosols consisting of sodium peroxides, hydroxides, carbonates, and bicarbonates. In addition to being toxic (in oxide form), this aerosol will then become radioactive. If such aerosols are leaked into the environment, they can pose a danger to the ecosystem. Depending on the chemical affinity of these chemical forms with fission products, the radiological consequences of an SA leading to containment leak tightness loss will also be affected. This work is split into two phases. Firstly, a method to theoretically understand the kinetics and thermodynamics of the heterogeneous reaction between sodium aerosols and fission products: I2 and HI are proposed. Ab-initio, density functional theory (DFT) calculations using Vienna ab-initio simulation package are carried out to develop an understanding of the surfaces of sodium carbonate (Na2CO3) aerosols and hence provide insight on its affinity towards iodine species. A comprehensive study of I2 and HI adsorption, as well as bicarbonate formation on the calculated lowest energy surface of Na2CO3, was performed which provided adsorption energies and description of the optimized configuration of adsorbate on the stable surface. Secondly, the heterogeneous reaction between (I2)g and Na2CO3 aerosols were investigated experimentally. To study this, (I2)g was generated by heating a permeation tube containing solid I2, and, passing it through a reaction chamber containing Na2CO3 aerosol deposit. The concentration of iodine was then measured at the exit of the reaction chamber. Preliminary observations indicate that there is an effective uptake of (I2)g on Na2CO3 surface, as suggested by our theoretical chemistry calculations. This work is the first step in addressing the gaps in knowledge of in-containment and atmospheric source term which are essential aspects of safety evaluation of SFR SA. In particular, this study is aimed to determine and characterize the radiological and chemical source term. These results will then provide useful insights for the developments of new models to be implemented in integrated computer simulation tool to analyze and evaluate SFR safety designs.

Keywords: iodine adsorption, sodium aerosols, sodium cooled reactor, DFT calculations, sodium carbonate

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Authors: Amir E. Amirzadeh, Richard K. Strand

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Moisture-induced problems are a significant concern for building owners, architects, construction managers, and building engineers, as they can have substantial impacts on building enclosures' durability and performance. Computational analyses, such as hygrothermal and thermal analysis, can provide valuable information and demonstrate the expected relative performance of building enclosure systems but are not grounded in absolute certainty. This paper evaluates the hygrothermal performance of common enclosure systems in hospitals in cold climates. The study aims to investigate the impact of exterior wall systems on hospitals, focusing on factors such as durability, construction deficiencies, and energy performance. The study primarily examines the impact of air leakage and vapor retarding layers relative to energy consumption. While these factors have been studied in residential and commercial buildings, there is a lack of information on their impact on hospitals in a holistic context. The study integrates various research studies and professional experience in hospital building design to achieve its objective. The methodology involves surveying and observing exterior wall assemblies, reviewing common exterior wall assemblies and details used in hospital construction, performing simulations and numerical analyses of various variables, validating the model and mechanism using available data from industry and academia, visualizing the outcomes of the analysis, and developing a mechanism to demonstrate the relative performance of exterior wall systems for hospitals under specific conditions. The data sources include case studies from real-world projects and peer-reviewed articles, industry standards, and practices. This research intends to integrate and analyze the in-situ and as-designed performance and durability of building enclosure assemblies with numerical analysis. The study's primary objective is to provide a clear and precise roadmap to better visualize and comprehend the correlation between the durability and performance of common exterior wall systems used in the construction of hospitals and the energy consumption of these buildings under certain static and dynamic conditions. As the construction of new hospitals and renovation of existing ones have grown over the last few years, it is crucial to understand the effect of poor detailing or construction deficiencies on building enclosure systems' performance and durability in healthcare buildings. This study aims to assist stakeholders involved in hospital design, construction, and maintenance in selecting durable and high-performing wall systems. It highlights the importance of early design evaluation, regular quality control during the construction of hospitals, and understanding the potential impacts of improper and inconsistent maintenance and operation practices on occupants, owner, building enclosure systems, and Heating, Ventilation, and Air Conditioning (HVAC) systems, even if they are designed to meet the project requirements.

Keywords: hygrothermal analysis, building enclosure, hospitals, energy efficiency, optimization and visualization, uncertainty and decision making

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Authors: Lekgowa Collen Makola, Cecil Naphtaly Moro Ouma, Sharon Moeno, Langelihle Dlamini

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In recent years, advancement in the field of nanotechnology has evolved new strategies to address energy and environmental issues. Amongst the developing technologies, visible-light-driven photocatalysis is regarded as a sustainable approach for energy production and environmental detoxifications, where transition metal oxides (TMOs) and metal-free carbon-based semiconductors such as graphitic carbon nitride (CN) evidenced notable potential in this matter. Herein, g-C₃N₄@WO₃@Ti₃C₂Tx three-component multijunction photocatalyst was fabricated via facile ultrasonic-assisted self-assembly, followed by calcination to facilitate extensive integrations of the materials. A series of different Ti₃C₂ wt% loading in the g-C₃N4@WO₃@Ti₃C₂Tx were prepared and represented as 1-CWT, 3-CWT, 5-CWT, and 7-CWT corresponding to 1, 3, 5, and 7wt%, respectively. Systematic characterization using spectroscopic and microscopic techniques were employed to validate the successful preparation of the photocatalysts. Enhanced optoelectronic and photoelectrochemical properties were observed for the WO₃@Ti₃C2@g-C₃N4 heterostructure with respect to the individual materials. Photoluminescence spectra and Nyquist plots show restrained recombination rates and improved photocarrier conductivities, respectively, and this was credited to the synergistic coupling effect and the presence of highly conductive Ti₃C2 MXene. The strong interfacial contact surfaces upon the formation of the composite were confirmed using XPS. Multiple charge transfer mechanisms were proposed for the WO3@Ti3C₂@g-C3N4, which couples Z-scheme and Schottky-junction mediated with Ti3C2 MXene. Bode phase plots show improved charge carrier life-times upon the formation of the multijunctional photocatalyst. Moreover, transient photocurrent density of 7-CWT is 40 and seven (7) times higher compared to that of g-C₃N4 and WO3, correspondingly. Unlike in the traditional Z-Scheme, the formed ternary heterostructure possesses interfaces through the metallic 2D Ti₃C₂ MXene, which provided charge transfer channels for efficient photocarrier transfers with carrier concentrations (ND) of 17.49×1021 cm-3 and 4.86% photo-to-chemical conversion efficiency. The as-prepared ternary g-C₃N₄@WO₃@Ti₃C₂Tx exhibited excellent photoelectrochemical properties with reserved redox band potential potencies to facilitate efficient photo-oxidation and -reduction reactions. The fabricated multijunction photocatalyst exhibits potentials to be used in an extensive range of photocatalytic process vis., production of valuable hydrocarbons from CO₂, production of H₂, and degradation of a plethora of pollutants from wastewater.

Keywords: photocatalysis, Z-scheme, multijunction heterostructure, Ti₃C₂ MXene, g-C₃N₄

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Authors: Norshazmira Mat Azmi, Sayidal El Fatimah Masnan, Shatirah Akib

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Boundless renewable energy, such as tidal energy, tidal current energy, wave energy, thermal energy and chemical energy are covered and possessed by oceans. The hybrid system helps in improving the economic and environmental sustainability of renewable energy systems to fulfill the energy demand. The objective and concept of hybridizing renewable energy is to meet the desired system requirements, with the lowest value of the energy cost. This paper reviews applications of using hybrid power generation system for remote area. It also highlights the future directions to investigate the impacts of surface waves on turbine design and performance. The importance of understanding the site-specific wave conditions could also been explored.

Keywords: hybrid, marine current energy, tidal turbine, wave turbine

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Authors: Débora V. Busman, Venerando E. Amaro, Mattheus da C. Prudêncio

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Prognostic studies of the shoreline are of utmost importance for Ponta Negra Beach, located in Natal, Northeastern Brazil, where the infrastructure recently built along the shoreline is severely affected by flooding and erosion. This study compares shoreline predictions using three linear regression methods (LMS, LRR and WLR) and tries to discern the best method for different shoreline position scenarios. The methods have shown erosion on the beach in each of the scenarios tested, even in less intense dynamic conditions. The WLA_A with confidence interval of 95% was the well-adjusted model and calculated a retreat of -1.25 m/yr to -2.0 m/yr in hot spot areas. The change of the shoreline on Ponta Negra Beach can be measured as a negative exponential curve. Analysis of these methods has shown a correlation with the morphodynamic stage of the beach.

Keywords: coastal erosion, prognostic model, DSAS, environmental safety

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Authors: Atbin Mahabbati, Jason Beringer, Matthias Leopold

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To address the global challenges of climate and environmental changes, there is a need for quantifying and reducing uncertainties in environmental data, including observations of carbon, water, and energy. Global eddy covariance flux tower networks (FLUXNET), and their regional counterparts (i.e., OzFlux, AmeriFlux, China Flux, etc.) were established in the late 1990s and early 2000s to address the demand. Despite the capability of eddy covariance in validating process modelling analyses, field surveys and remote sensing assessments, there are some serious concerns regarding the challenges associated with the technique, e.g. data gaps and uncertainties. To address these concerns, this research has developed an ensemble model to fill the data gaps of CO₂ flux to avoid the limitations of using a single algorithm, and therefore, provide less error and decline the uncertainties associated with the gap-filling process. In this study, the data of five towers in the OzFlux Network (Alice Springs Mulga, Calperum, Gingin, Howard Springs and Tumbarumba) during 2013 were used to develop an ensemble machine learning model, using five feedforward neural networks (FFNN) with different structures combined with an eXtreme Gradient Boosting (XGB) algorithm. The former methods, FFNN, provided the primary estimations in the first layer, while the later, XGB, used the outputs of the first layer as its input to provide the final estimations of CO₂ flux. The introduced model showed slight superiority over each single FFNN and the XGB, while each of these two methods was used individually, overall RMSE: 2.64, 2.91, and 3.54 g C m⁻² yr⁻¹ respectively (3.54 provided by the best FFNN). The most significant improvement happened to the estimation of the extreme diurnal values (during midday and sunrise), as well as nocturnal estimations, which is generally considered as one of the most challenging parts of CO₂ flux gap-filling. The towers, as well as seasonality, showed different levels of sensitivity to improvements provided by the ensemble model. For instance, Tumbarumba showed more sensitivity compared to Calperum, where the differences between the Ensemble model on the one hand and the FFNNs and XGB, on the other hand, were the least of all 5 sites. Besides, the performance difference between the ensemble model and its components individually were more significant during the warm season (Jan, Feb, Mar, Oct, Nov, and Dec) compared to the cold season (Apr, May, Jun, Jul, Aug, and Sep) due to the higher amount of photosynthesis of plants, which led to a larger range of CO₂ exchange. In conclusion, the introduced ensemble model slightly improved the accuracy of CO₂ flux gap-filling and robustness of the model. Therefore, using ensemble machine learning models is potentially capable of improving data estimation and regression outcome when it seems to be no more room for improvement while using a single algorithm.

Keywords: carbon flux, Eddy covariance, extreme gradient boosting, gap-filling comparison, hybrid model, OzFlux network

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Authors: Marina Gold, Yves Jackson, David Parrat

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The high predominance of Latin American migrants in Geneva from countries where Chagas disease is endemic (Bolivia, Brazil, Argentina, Colombia) is increasing the incidence of chronic Chagas-related problems, especially cardiovascular complications. The precarious migratory status of what are mostly undocumented migrants complicates access to health and affects patients’ and doctors’ health perceptions regarding screening, treatment and monitoring of Chagas-related health concerns. This project results from a 3 year collaboration between the Geneva University Hospital and the NGO Mundo Sano to understand the following questions: 1) how do Latin American migrants perceive their health? 2) What do they understand from Chagas disease? 3) Are patients’ and doctors’ health perceptions similar or do they have competing agendas? This paper aims to present the results of a long-term study that interrogates health perceptions among Latin American migrants in Geneva. The first phase consisted in completing surveys at three community screening events (2016, 2017. 2018), and the results of these surveys reveal the subordination of the importance of health to that of having met economic family obligation. That is, health is important only when it becomes an impediment to economic gain. The contradictory result emerged that people are aware of the importance of health prevention in order to ensure long-term health, but they do not always have agency over their life-style habits (healthy food, regular exercise, emotional stability). The second phase of the research collected open-ended interviews with selected participants, in order to explore in more detail how Latin American migrants deal with Chagas in a different socio-political and economic context to that of endemic countries. These interviews (5 in total) reveal mixed methods of managing health: social networks, access to health care transnationally (in Geneva, Spain and back in their home country), and different valuations of health problems in each situation. The third phase consisted in observations of doctor-patient consultations and further extended interviews with patients to determine doctor/patient health perceptions around Chagas disease. This phase is ongoing, but it has yielded preliminarily observations regarding the expectations that patients’ have of doctors, and the understanding of doctors’ to patients’ complex situations. Positive and complementary health perceptions include patients’ feeling that doctors in Geneva are more understanding, more knowledgeable and less racist than those in their home country, who do not provide detailed information about Chagas or its treatment and discriminate against them for being indigenous or from poor rural areas, enabling a better communication between doctors and patients. Possible conflicting health perceptions include patients addressing their health concerns more holistically and encountering the specialist’s limitations to only treating one health concern, given time limitations and lack of competition with their colleagues (the general practitioner that referred the patient, for example). The implications of this study extend the case of Chagas disease in Geneva and is relevant for all chronic concerns and migratory contexts of precarity.

Keywords: chagas disease, health perceptions, Latin American Migrants, non-endemic countries

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Authors: Sisay Tamrat Ayalew

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This paper aims to explore the two contradictory debates about the educational philosophy of universities in the context of Ethiopia. It also explores how the understanding of the philosophy of the university is shaped by environmental factors and exacerbates the marginalization of youth. On the one hand, universities are perceived as places where knowledge can solve a certain practical problem. On the other hand, universities are places where knowledge is produced and disseminated irrespective of its immediate use value. This study found that understanding the philosophy of education varies across time and place. In the Ethiopian context, there is neither a disinterested pursuit of knowledge nor an instrumentalist epistemology nor a synthesis of the two. It disregards the value of knowledge altogether and overly simplifies the philosophy of instrumentalist epistemology to the extent of buying and selling certificates, even in the absence of formal training.

Keywords: philosophy of universities, marginalized youth, diploma mill, instrumentalist epistemology, disinterested pursuit

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Authors: Nasser Ghassembaglou, Abdullah Bolek, Oktay Yilmaz, Ertan Oznergiz, Hikmet Kocabas, Safak Yilmaz

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Nanofibers are effective material which have frequently been investigated to produce high quality air filters. As an environmental approach our aim is to achieve nanofibers by melting. In spun-bond systems extruder, spin-pump, nozzle package and attenuator are used. Molten polymer which flows from extruder is made steady by spin-pump. Regular melt passes through nozzle holes and forms fibers under high pressure. The fibers pulled from nozzle are shrunk to micron size by an attenuator, after solidification they are collected on a conveyor. In this research different designs of attenuator system have been studied and also CFD analysis have been done on them. Afterwards, one of these designs tested and finally some optimizations have been done to reduce pressure loss and increase air velocity.

Keywords: attenuator, nanofiber, spun-bond, extruder

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Authors: Sonia Ben Hamza, Sabra Habli, Nejla Mahjoub Saïd, Hervé Bournot, Georges Le Palec

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This paper spots light on the effect of a point source pollution on streams, stemming out from intentional release caused by unconscious facts. The consequences of such contamination on ecosystems are very serious. Accordingly, effective tools are highly demanded in this respect, which enable us to come across an accurate progress of pollutant and anticipate different measures to be applied in order to limit the degradation of the environmental surrounding. In this context, we are eager to model a pollutant dispersion of a free surface flow which is ejected by an outfall sewer of an urban sewerage network in coastal water taking into account the influence of climatic parameters on the spread of pollutant. Numerical results showed that pollutant dispersion is merely due to the presence of vortices and turbulence. Hence, it was realized that the pollutant spread in seawater is strongly correlated with climatic conditions in this region.

Keywords: coastal waters, numerical simulation, pollutant dispersion, turbulent flows

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Authors: Afzaal Gulzar, Shafaq Mubarak, M. Zia-Ur-Rehman

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Industrial waste waters put environmental constrains to the water quality of aqueous reserves. Number of techniques has been used to treat them before disposal to water bodies. In this work a novel green approach is study by using poultry waste eggshells as a low cost efficient adsorbent for the dyes present in industrial effluent of textile and paper industries. The developed technique not only used to treat contaminated waters but also resulted in the utilization of poultry eggshell waste which in turn assists in solid waste management. Batch sorption studies like contact time, adsorbent dose, dye concentration, temp and pH has been conducted to find the optimum adsorption parameters.

Keywords: green technology, solid waste management, industrial effluent, eggshell waste utilization, waste water treatment

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Authors: B. S. Premalatha, Mereen Rose Babu, Vaishali Prabhu

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Background: Dysphagia must be assessed, either subjectively or objectively, in order to properly address the swallowing difficulty. Providing therapeutic care to patients with dysphagia via tele mode was one approach for providing clinical services during the COVID-19 epidemic. As a result, the teleassessment of dysphagia has increased in India. Aim: This study aimed to identify challenges faced by Indian SLPs while providing teleassessment to individuals with dysphagia during the outbreak of COVID-19 from 2020 to 2021. Method: After receiving approval from the institute's institutional review board and ethics committee, the current study was carried out. The study was cross-sectional in nature and lasted from 2020 to 2021. The study enrolled participants who met the inclusion and exclusion criteria of the study. It was decided to recruit roughly 246 people based on the sample size calculations. The research was done in three stages: questionnaire development and content validation, questionnaire administration. Five speech and hearing professionals' content verified the questionnaire for faults and clarity. Participants received questionnaires via various social media platforms such as e-mail and WhatsApp, which were written in Microsoft Word and then converted to Google Forms. SPSS software was used to examine the data. Results: In light of the obstacles that Indian SLPs encounter, the study's findings were examined. Only 135 people responded. During the COVID-19 lockdowns, 38% of participants said they did not deal with dysphagia patients. After the lockout, 70.4% of SLPs kept working with dysphagia patients, while 29.6% did not. From the beginning of the oromotor examination, the main problems in completing tele evaluation of dysphagia have been highlighted. Around 37.5% of SLPs said they don't undertake the OPME online because of difficulties doing the evaluation, such as the need for repeated instructions from patients and family members and trouble visualizing structures in various positions. The majority of SLPs' online assessments were inefficient and time-consuming. A bigger percentage of SLPs stated that they will not advocate tele evaluation in dysphagia to their colleagues. SLPs' use of dysphagia assessment has decreased as a result of the epidemic. When it came to the amount of food, the majority of people proposed a small amount. Apart from placing the patient for assessment and gaining less cooperation from the family, most SLPs found that Internet speed was a source of concern and a barrier. Hearing impairment and the presence of a tracheostomy in patients with dysphagia proved to be the most difficult conditions to treat online. For patients with NPO, the majority of SLPs did not advise tele-evaluation. In the anterior region of the oral cavity, oral meal residue was more visible. The majority of SLPs reported more anterior than posterior leakage. Even while the majority of SLPs could detect aspiration by coughing, many found it difficult to discern the gurgling tone of speech after swallowing. Conclusion: The current study sheds light on the difficulties that Indian SLPs experience when assessing dysphagia via tele mode, indicating that tele-assessment of dysphagia is still to gain importance in India.

Keywords: dysphagia, teleassessment, challenges, Indian SLP

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Authors: Mme Hamani Née Guessas Ghaniya

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The transport is the base of the development of the exchanges and the business, being both a recognized determiner of the economic and social development. The development of the transport is in the center of the big challenges of development of countries, but it is also at the heart of big contradictions, since we integrate the environmental issues which are bound to him, in particular through the questions of energy. Indeed, the energy consumption by the sector of transport is one of bigger concerns, because it is increasing and it has a big impact on our environment. The main consequences are, the atmospheric pollution causing an increase of the greenhouse effect which causes a global warming. These global warming risks to engender a partial cast iron of polar caps so raising the level of seas, flooding the low coastal zones, certain islands and the deltas. Thus, the purpose of this communication is to present the impact of the energy consumption by the sector of transport on the air quality, showing its effect on the health and on the global warming.

Keywords: energy consumption, sector of transport, air quality, atmospheric pollution

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Authors: Ngabirano Levis

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One of Africa’s major environmental challenges remains air pollution. In 2017, UNICEF estimated over 400,000 children in Africa died as a result of indoor pollution, while 350 million children remain exposed to the risks of indoor pollution due to the use of biomass and burning of wood for cooking. Over time, indeed, the major causes of mortality across Africa are shifting from the unsafe water, poor sanitation, and malnutrition to the ambient and household indoor pollution, and greenhouse gas (GHG) emissions remain a key factor in this. In addition, studies by the OECD estimated that the economic cost of premature deaths due to Ambient Particulate Matter Pollution (APMP) and Household Air Pollution across Africa in 2013 was about 215 Billion US Dollars and US 232 Billion US Dollars, respectively. This is not only a huge cost for a continent where over 41% of the Sub-Saharan population lives on less than 1.9 US Dollars a day but also makes the people extremely vulnerable to the negative climate change and environmental degradation effects. Such impacts have led to extended droughts, flooding, health complications, and reduced crop yields hence food insecurity. Climate change, therefore, poses a threat to global targets like poverty reduction, health, and famine. Despite efforts towards mitigation, air contributors like carbon dioxide emissions are on a generally upward trajectory across Africa. In Egypt, for instance, emission levels had increased by over 141% in 2010 from the 1990 baseline. Efforts like the climate change adaptation and mitigation financing have also hit obstacles on the continent. The International Community and developed nations stress that Africa still faces challenges of limited human, institutional and financial systems capable of attracting climate funding from these developed economies. By using the qualitative multi-case study method supplemented by interviews of key actors and comprehensive textual analysis of relevant literature, this paper dissects the key emissions and air pollutant sources, their impact on the well-being of the African people, and puts forward suggestions as well as a remedial mechanism to these challenges. The findings reveal that whereas climate change mitigation plans appear comprehensive and good on paper for many African countries like Uganda; the lingering political interference, limited research guided planning, lack of population engagement, irrational resource allocation, and limited system and personnel capacity has largely impeded the realization of the set targets. Recommendations have been put forward to address the above climate change impacts that threaten the food security, health, and livelihoods of the people on the continent.

Keywords: Africa, air pollution, climate change, mitigation, emissions, effective planning, institutional strengthening

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Authors: Mary Hanhoun, Jilla Bamarni, Anne-Sophie Bougard

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INSPIR’ECO is a 18-month research and innovation project that aims to specify and develop a tool to offer new services for industrials and territorial planners/managers based on Industrial Ecology Principles. This project is carried out on the territory of Salaise Sablons and the services are designed to be deployed on other territories. Salaise-Sablons area is located in the limit of 5 departments on a major European economic axis multimodal traffic (river, rail and road). The perimeter of 330 ha includes 90 hectares occupied by 20 companies, with a total of 900 jobs, and represents a significant potential basin of development. The project involves five multi-disciplinary partners (Syndicat Mixte INSPIRA, ENGIE, IDEEL, IDEAs Laboratory and TREDI). INSPIR’ECO project is based on the principles that local stakeholders need services to pool, share their activities/equipment/purchases/materials. These services aims to : 1. initiate and promote exchanges between existing companies and 2. identify synergies between pre-existing industries and future companies that could be implemented in INSPIRA. These eco-industrial synergies can be related to: the recovery / exchange of industrial flows (industrial wastewater, waste, by-products, etc.); the pooling of business services (collective waste management, stormwater collection and reuse, transport, etc.); the sharing of equipments (boiler, steam production, wastewater treatment unit, etc.) or resources (splitting jobs cost, etc.); and the creation of new activities (interface activities necessary for by-product recovery, development of products or services from a newly identified resource, etc.). These services are based on IT tool used by the interested local stakeholders that intends to allow local stakeholders to take decisions. Thus, this IT tool: - include an economic and environmental assessment of each implantation or pooling/sharing scenarios for existing or further industries; - is meant for industrial and territorial manager/planners - is designed to be used for each new industrial project. - The specification of the IT tool is made through an agile process all along INSPIR’ECO project fed with: - Users expectations thanks to workshop sessions where mock-up interfaces are displayed; - Data availability based on local and industrial data inventory. These input allow to specify the tool not only with technical and methodological constraints (notably the ones from economic and environmental assessments) but also with data availability and users expectations. A feedback on innovative resource management initiatives in port areas has been realized in the beginning of the project to feed the designing services step.

Keywords: development opportunities, INSPIR’ECO, INSPIRA, industrial ecology, planification, synergy identification

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Authors: Chidiebere C. Agoha, Armstong C. Awuzie, Chukwuebuka N. Onwubuariri, Joy O. Njoku

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Spatial analysis is a field of study that utilizes geographic or spatial information to understand and analyze patterns, relationships, and trends in data. It is characterized by the use of geographic or spatial information, which allows for the analysis of data in the context of its location and surroundings. It is different from non-spatial or aspatial techniques, which do not consider the geographic context and may not provide as complete of an understanding of the data. Spatial analysis is applied in a variety of fields, which includes urban planning, environmental science, geosciences, epidemiology, marketing, to gain insights and make decisions about complex spatial problems. This review paper explores definitions of spatial analysis from various sources, including examples of its application and different analysis techniques such as Buffer analysis, interpolation, and Kernel density analysis (multi-distance spatial cluster analysis). It also contrasts spatial analysis with non-spatial analysis.

Keywords: aspatial technique, buffer analysis, epidemiology, interpolation

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Authors: M. Szechynska-Hebda, M. Sobczak, E. Rozanska, J. Troczynska, Z. Banaszak, N. Hordyńska, M. Dyda, M. Wedzony

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Chloroplasts, as essential organelles for photosynthesis, play a critical role in plant development. However, disturbances in the proper functioning of chloroplasts, in the extreme case manifesting as albinism of tissues and whole plants, are a phenomenon often occurring in conditions deviating from natural (e.g., in vitro cultures applied in breeding programs). Using whole-transcriptome analysis (RNA-Seq) together with light, fluorescent and electron microscopy, it was shown, that development of chloroplasts and formation of green or albino plants in the androgenesis process are genotype-dependent; however, they could be modulated by sub-optimal temperature treatment. The reprogramming of the microspore development from gametophytic to sporophytic, and then regeneration of green plant can be positively regulated by cold stress (4 ⁰C). A high temperature stress (32 ⁰C) can induce androgenesis, but it is a factor negatively influencing green plant regeneration (promoting albinism). A similar effect on microspores, androgenesis, and subsequent chloroplast formation, is elicited as a result of postponing the date of spike collection from spring to summer in field conditions (natural temperature rise). It is determined in both environmental or genotypic manner. The delay of the sowing date (environmental effect) or growing of late genotypes (genotypic effect) result in spike maturation at higher temperatures and significantly enhance albino plant formation in androgenesis process. Such a temperature system (4 ⁰C vs. 32 ⁰C) was used to study the chloroplast biogenesis process in wheat and triticale. It was shown, that efficiency of physiological processes differentiates microspore development during cold reprograming in genotypes susceptible and resistant to androgenesis. Moreover, a great variation in developmental stages of the microspores in one anther is observed for susceptible genotypes. Microspores that are more physiologically active under cold conditions can activate signaling pathways and processes, which provide an appropriate supply of metabolites to cell compartments. This, in turn, fully correlates with the genotype-dependent efficiency of chloroplast formation (or different types of plastid) at particular steps of androgenesis. The effect obtained after applying a high temperature stress is different. High temperature causes a significant acceleration of microspore development and less variation in developmental stages at the end of the treatment. Therefore, the developmental diversity of the microspores in one anther seems to be a critical factor for subsequent cell and chloroplast differentiation. The work was financed by Ministry of Agriculture and Rural Development within Program: 'Biological Progress in Plant Production', project no HOR.hn.802.15.2018

Keywords: androgenesis, chloroplast biogenesis, temperature stress, wheat

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Authors: Jesus Alfredo Ortega Granados, Pandiyan Thangarasu

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Antibiotic tetracycline presents as a micro-contaminant in fresh water, wastewater and soils, causing environmental and health problems. In this work, tetracycline (TC) has been employed as chemo-sensor for the recognition of Al³⁺ without interring other ions, and the results show that it enhances the fluorescence intensity for Al³⁺ and there is no interference from other coexisting cation ions (Cd²⁺, Ni²⁺, Co²⁺, Sr²⁺, Mg²⁺, Fe³⁺, K⁺, Sm³⁺, Ag⁺, Na⁺, Ba²⁺, Zn²⁺, and Mn²⁺). For the addition of Cu²⁺ to [TET-Al³⁺], it appears that the intensity of fluorescence has been quenched. Other combinations of metal ions in addition to TC do not change the fluorescence behavior. The stoichiometry determined by Job´s plot for the interaction of TC with Al³⁺ was found to be 1:1. Importantly, the detection of Al³⁺⁺ successfully employed in the real samples like living cells, and it was found that TC efficiently performs as a fluorescent probe for Al³⁺ ion in living systems, especially in Saccharomyces cerevisiae; this is confirmed by confocal laser scanning microscopy.

Keywords: chemo-sensor, recognition of Al³⁺ ion, Saccharomyces cerevisiae, tetracycline,

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Authors: Cisil Gulumser, Francesc Medina, Sevil Veli

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In this study, the synthesis of photocatalytic Bi₂WO₆ was practiced with simple heating processes and the effects of these treatments on the production of the desired compound were investigated. For this purpose, experiments with Bi(NO₃)₃.5H₂O and H₂WO₄ precursors were carried out to synthesize Bi₂WO₆ by four different combinations. These four combinations were grouped in two main sets as ‘treated in microwave reactor’ and ‘directly filtrated’; additionally these main sets were grouped into two subsets as ‘calcined’ and ‘not calcined’. Calcination processes were conducted at temperatures of 400ᵒC, 600ᵒC, and 800ᵒC. X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEM) analyses were performed in order to investigate the crystal structure of powdered product synthesized with each combination. The highest crystallization of produced compounds was observed for calcination at 600ᵒC from each main group.

Keywords: bismuth tungstate, crystallization, microwave, photocatalysts

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Authors: Mahsa Ja’fari, Mohammad R. Khosravi-Nikou, Mohsen Motavassel

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A comprehensive development towards the production of ultra-clean fuels as a feed stoke is getting to raise due to the increasing use of diesel fuels and global air pollution. Production of environmental-friendly fuels can be achievable by some limited single methods and most integrated ones. Oxidative desulfurization (ODS) presents vast ranges of technologies possessing suitable characteristics with regard to the Fenton process. Using toluene as a model fuel feed with dibenzothiophene (DBT) as a sulfur compound under various operating conditions is the attempt of this study. The results showed that this oxidative process followed a pseudo-first order kinetics. Removal efficiency of 77.43% is attained under reaction time of 40 minutes with (Fe⁺²/H₂O₂) molar ratio of 0.05 in acidic pH environment. In this research, temperature of 50 °C represented the most influential role in proceeding the reaction.

Keywords: design of experiment (DOE), dibenzothiophene (DBT), optimization, oxidative desulfurization (ODS)

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Authors: Nabila Ihaddadene, Razika Ihaddadene, Abdelwahaab Betka

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1973 energy crisis (rising oil prices) pushed the world to consider other alternative energy resources to existing conventional energies consisting predominantly of hydrocarbons. Renewable energies such as solar, the wind and geothermal have received renewed interest, especially to preserve nature ( the low-temperature rise of global environmental problems). Solar energy as an available, cheap and environmental friendly alternative source has various applications such as heating, cooling, drying, power generation, etc. In short, there is no life on earth without this enormous nuclear reactor, called the sun. Among available solar collector designs, flat plate collector (FPC) is low-temperature applications (heating water, space heating, etc.) due to its simple design and ease of manufacturing. Flat plate collectors are permanently fixed in position and do not track the sun (non-concentrating collectors). They operate by converting solar radiation into heat and transferring that heat to a working fluid (usually air, water, water plus antifreeze additive) flowing through them. An FPC generally consists of the main following components: glazing, absorber plate of high absorptivity, fluid tubes welded to or can be an integral part of the absorber plate, insulation and container or casing of the above-mentioned components. Insulation is of prime importance in thermal applications. There are three main families of insulation: mineral insulation; vegetal insulation and synthetic organic insulation. The old houses of the inhabitants of North Africa were built of brick made of composite material that is clay and straw. These homes are characterized by their thermal comfort; i.e. the air inside these houses is cool in summer and warm in winter. So, the material composed from clay and straw act as a thermal insulation. In this research document, the polystyrene used as insulation in the ET200 flat plate solar collector is replaced by the cheapest natural material which is clay and straw. Trials were carried out on a solar energy demonstration system (ET 200). This system contains a solar collector, water storage tank, a high power lamp simulating solar energy and a control and command cabinet. In the experimental device, the polystyrene is placed under the absorber plate and in the edges of the casing containing the components of the solar collector. In this work, we have replaced the polystyrene of the edges by the composite material. The use of the clay and straw as insulation instead of the polystyrene increases temperature difference (T2-T1) between the inlet and the outlet of the absorber by 0.9°C; thus increases the useful power transmitted to water in the solar collector. Tank Water is well heated when using the clay and straw as insulation. However, it is less heated when using the polystyrene as insulation. Clay and straw material improves also the performance of the solar collector by 5.77%. Thus, it is recommended to use this cheapest non-polluting material instead of synthetic insulation to improve the performance of the solar collector.

Keywords: clay, insulation material, polystyrene, solar collector, straw

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Authors: Kholod Hajo

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In this study COMSOL Multiphysics was used to design lateral flow biosensors (LFBs) which provide advantages in low cost, simplicity, rapidity, stability and portability thus making LFBs popular in biomedical, agriculture, food and environmental sciences. This study was focused on simulation model of biosensor based on gold nanoparticles (GNPs) designed using software package (COMSOL Multiphysics), the magnitude of the laminar velocity field in the flow cell, concentration distribution in the analyte stream and surface coverage of adsorbed species and average fractional surface coverage of adsorbed analyte were discussed from the model and couples of suggestion was given in order to functionalize GNPs and to increase the accuracy of the biosensor design, all above were obtained acceptable results.

Keywords: model, gold nanoparticles, biosensor, COMSOL Multiphysics

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Authors: Sz. Klátyik, B. Darvas, M. Mörtl, M. Ottucsák, E. Takács, H. Bánáti, L. Simon, G. Gyurcsó, A. Székács

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Environmental and health safety of condiments used for spicing food products in food processing or by culinary means receive relatively low attention, even though possible contamination of spices may affect food quality and safety. Contamination surveys mostly focus on microbial contaminants or their secondary metabolites, mycotoxins. Chemical contaminants, particularly pesticide residues, however, are clearly substantial factors in the case of given condiments in the Capsicum family including spice paprika and chilli. To assess food safety and support the quality of the Hungaricum product spice paprika, the pesticide residue status of spice paprika and chilli is assessed on the basis of reported pesticide contamination cases and non-compliances in the Rapid Alert System for Food and Feed of the European Union since 1998.

Keywords: spice paprika, Capsicum, pesticide residues, RASFF

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Authors: Faheemah N. Mustafaa, Tamarie Macon, Tabbye Chavous

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A major concern of university leaders worldwide is how to create environments where students from diverse racial/ethnic, national, and cultural backgrounds can thrive. Over the past decade or so in the United States, African American women have done exceedingly well in terms of college enrollment, academic performance, and completion. However, the relative academic successes of African American women in higher education has in some ways overshadowed social challenges many Black women continue to encounter on college campuses in the United States. Within predominantly White institutions (PWIs) in particular, there is consistent evidence that many Black students experience racially hostile climates. However, research studies on racial climates within PWIs have mostly focused on cross-sectional comparisons of minority and majority group experiences, and few studies have examined campus racial climate in relation to short- and longer-term well-being. One longitudinal study reported that African American women’s psychological well-being was positively related to their comfort in cross-racial interactions (a concept closely related to campus climate). Thus, our primary research question was: Do African American women’s perceptions of campus climate (tension and positive association) during their freshman year predict their reports of psychological distress and well-being (self-acceptance) during their sophomore year? Participants were part of a longitudinal survey examining African American college students’ academic identity development, particularly in Science, Technology, Engineering, and Mathematics (STEM) fields. The final subsample included 134 self-identified African American/Black women enrolled in PWIs. Accounting for background characteristics (mother’s education, family income, interracial contact, and prior levels of outcomes), we employed hierarchical regression to examine relationships between campus racial climate during freshman year and psychological adjustment one year later. Both regression models significantly predicted African American women’s psychological outcomes (for distress, F(7,91)= 4.34, p < .001; and for self-acceptance, F(7,90)= 4.92, p < .001). Although none of the controls were significant predictors, perceptions of racial tension on campus were associated with both distress and self-acceptance. More perceptions of tension were related to African American women’s greater psychological distress the following year (B= 0.22, p= .01). Additionally, racial tension predicted later self-acceptance in the expected direction: Higher first-year reports of racial tension were related to less positive attitudes toward the self during the sophomore year (B= -0.16, p= .04). However, perceptions that it was normative for Black and White students to socialize on campus (or positive association scores) were unrelated to psychological distress or self-acceptance. Findings highlight the relevance of examining multiple facets of campus racial climate in relation to psychological adjustment, with possible emphasis on the import of racial tension on African American women’s psychological adjustment. Results suggest that negative dimensions of campus racial climate may have lingering effects on psychological well-being, over and above more positive aspects of climate. Thus, programs targeted toward improving student relations on campus should consider addressing cross-racial tensions.

Keywords: higher education, psychological adjustment, university climate, university students

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Authors: Malee Santikunaporn, Tattep Techopittayakul, Channarong Asavatesanupap

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Biofuel production especially that of biodiesel has gained tremendous attention during the last decade due to environmental concerns and shortage in petroleum oil reservoir. This research aims to investigate the influences of operating parameters, such as the alcohol-to-oil molar ratio (4:1, 6:1, and 9:1) and the amount of catalyst (1, 1.5, and 2 wt.%) on the trans esterification of refined palm oil (RPO) in a medium-scale oscillatory baffle reactor.  It has been shown that an increase in the methanol-to-oil ratio resulted in an increase in fatty acid methyl esters (FAMEs) content. The amount of catalyst has an insignificant effect on the FAMEs content. Engine testing was performed on B0 (100 v/v% diesel) and blended fuel or B50 (50 v/v% diesel). Combustion of B50 was found to give lower torque compared to pure diesel. Exhaust gas from B50 was found to contain lower concentration of CO and CO₂.

Keywords: biodiesel, palm oil, transesterification, oscillatory baffled reactor

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Authors: Vitool Suksankavanich

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This preliminary research aimed to explore the development of wastewater management of Bang Pu Sub- District Municipality, Samutprakan Province, in order to establish appropriate model for effective wastewater management that fit to the context of the area. The research posed three questions: [i] to what extent the promotion of social responsibility awareness built among the local community resulted in effectiveness of the local wastewater management; [ii] did the waste disposal management of Bang Pu Industrial Estate contribute to the overall environmental quality of Bang Pu Sub- District Municipality; and [iii] did the relationship between the community and the industrial factories have any effect on the wastewater management. The in- depth interview revealed main obstacles occurred in the process of wastewater management in the area. The fieldwork also contributed to a product of an appropriate model of effective wastewater management.

Keywords: legitimacy theory, stakeholder theory, social responsibility, wastewater management

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Authors: M. A. Peribanez, G. Illan, I. De Blas, A. Muniesa, I. Ruiz-Zarzuela

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Intensive aquaculture is commonly associated with increased incidence of parasites. However, in Spain, the recent intensification of cyprinid production has not led to knowledge of the parasites that develop in the aquaculture facilities, the factors that affect their development and spread and the transmission between wild and cultivated fish species. The present study focuses on the knowledge of environmental factors, as well as host dependent factors, and their possible influence as risk factors in the incidence and intensity of parasitic infections. This work was conducted in the Duero River Basin, NW Spain. A total of 114 tenches (Tinca tinca) were caught in a fish farm and 667 specimens belonging to six species of cyprinid, not tench, in five rivers. An exhaustive search and microscopic identification of protozoa on skin and gills were carried out. Physical, chemical, and biological parameters of water samples from the capture points were determined. Only two ectoprotozoa were identified, Ichthyophthirius multifiliis and Tripartiella sp. In I. multifiliis, a high intensity of infection (more than 40 parasites on the body surface and more than 80 on gills) was determined in farmed tench (14%) and in Iberian barbel (Luciobarbus bocagei) (91%) and Duero nase (Pseudochondrostoma duriense) (71%) of middle stretches of rivers. The prevalence was similar between farmed tenches and cyprinids of middle courses. Tripartiella sp. was only found in barbels (prevalence in middle stretches, 0.7%) and in farmed tenches (63%), this species resulting in a high risk factor (odds ratio, OR= 1143) in the presence of the ciliate. There were no differences between the two species relative to the intensity of parasitization. Some of the physical, chemical and microbiological water quality parameters appear to be risk factors in the presence of I. multifiliis, with maximum OR of 8. Nevertheless, in Tripartiella sp., the risk is multiplied by 720 when the pH value exceeds 8.4, if we consider the total of the data, and it is increased more than 500 times if we only consider the values recorded in the fish farm (529 by nitrates > 3 mg/l; 530 by total coliforms > 100 CFU/100 ml). However, the high prevalence and risk of infection by I. multifiliis and Tripartiella sp. in fish farms should be related to environmental factors that dependent upon sampling point rather than in direct influence of the physical-chemical and biological parameters of the water. The high pH value recorded in the fish farm (9.62 ± 0.76) is the only parameter that we consider may have a substantial direct influence. Chronic exposure to alkaline pH levels can be a chronic stress generator, predisposing to parasitization by Tripartiella sp. In conclusion, often minor changes in ecosystem conditions, both natural and man-made, can modify the host-parasite relationship, resulting in an increase in the prevalence and intensity of parasitic infections in populations of cyprinids, sometimes causing disease outbreaks.

Keywords: cyprinids, fish, parasites, protozoa, risk factors

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Authors: Rodrigo M. Falleiro, Joaquim P. L. Parime, Luciano C. Santos, Rodrigo D. Silva

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The Cerrado biome is the most biodiverse savanna on the planet. Located in central Brazil, its preservation is seriously threatened by the advance of intensive agriculture and livestock. Conservation Units and Indigenous Lands are increasingly isolated and subject to mega wildfires. Among the characteristics of this savanna, we highlight the high rate of primary biomass production and the reduced occurrence of large grazing animals. In this biome, the predominant fauna is more dependent on the fruits produced by the dicotyledonous species in relation to other tropical savannas. Fire is a key element in the balance between mono and dicotyledons or between the arboreal and herbaceous strata. Therefore, applying fire regimes that maintain the balance between these strata without harming fruit production is essential in the conservation strategies of Cerrado's biodiversity. Recently, Integrated Fire Management has started to be implemented in Brazilian protected areas. As a result, management with prescribed burns has increasingly replaced strategies based on fire exclusion, which in practice have resulted in large wildfires, with highly negative impacts on fruit and fauna production. In the Indigenous Lands, these fires were carried out respecting traditional knowledge. The indigenous people showed great concern about the effects of fire on fruit plants and important animals. They recommended that the burns be carried out between April and May, as it would result in a greater production of edible fruits ("fruiting burning"). In other tropical savannas in the southern hemisphere, the preferential period tends to be later, in the middle of the dry season, when the grasses are dormant (June to August). However, in the Cerrado, this late period coincides with the flowering and sprouting of several important fruit species. To verify the best burning season, the present work evaluated the effects of fire on flowering and fruit production of theByrsonima sp., Mouriri pusa, Caryocar brasiliense, Anacardium occidentale, Pouteria ramiflora, Hancornia speciosa, Byrsonima verbascifolia, Anacardium humille and Talisia subalbens. The evaluations were carried out in the field, covering 31 Indigenous Lands that cover 104,241.18 Km², where 3,386 prescribed burns were carried out between 2015 and 2018. The burning periods were divided into early (carried out during the rainy season), modal or “fruiting” (carried out during the transition between seasons) and late (carried out in the middle of the dry season, when the grasses are dormant). The results corroborate the traditional knowledge, demonstrating that the modal burns result in higher rates of reproduction and fruit production. Late burns showed intermediate results, followed by early burns. We conclude that management strategies based mainly on forage production, which are usually applied in savannas populated by grazing ungulates, may not be the best management strategy for South American savannas. The effects of fire on fruit plants, which have a particular phenologicalsynchronization with the fauna cycle, also need to be observed during the prescription of burns.

Keywords: cerrado biome, fire regimes, native fruits, prescribed burns

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