Search results for: Soil Side Corrosion

Authors: Rikke Lybæk, Tyge Kjær

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The Baltic Sea is suffering from nitrogen and phosphorus pollution, which causes eutrophication of the maritime environment and hence threatens the biodiversity of the Baltic Sea area. The intensified quantity of nutrients in the water has created challenges with the growth of seaweed being discarded on beaches around the sea. The cast seaweed has led to odor problems hampering the use of beach areas around the Bay of Køge in Denmark. This is the case in, e.g., Solrød Municipality, where recreational activities have been disrupted when cast seaweed pile up on the beach. Initiatives have, however, been introduced within the municipality to remove the cast seaweed from the beach and utilize it for renewable energy production at the nearby Solrød Biogas Plant, thus being co-digested with animal manure for power and heat production. This paper investigates which type of technology application’s have been applied in the effort to optimize the collection of cast seaweed, and will further reveal, how the seaweed has been pre-treated at the biogas plant to be utilized for energy production the most efficient, hereunder the challenges connected with the content of sand. Heavy metal contents in the seaweed and how it is managed will also be addressed, which is vital as the digestate is utilized as soil fertilizer on nearby farms. Finally, the paper will outline the energy production scheme connected to the use of seaweed as feedstock for biogas production, as well as the amount of nitrogen-rich fertilizer produced. The theoretical approach adopted in the paper relies on the thinking of Circular Bio-Economy, where biological materials are cascaded and re-circulated etc., to increase and extend their value and usability. The data for this research is collected as part of the EU Interreg project “Cluster On Anaerobic digestion, environmental Services, and nuTrients removAL” (COASTAL Biogas), 2014-2020. Data gathering consists of, e.g., interviews with relevant stakeholders connected to seaweed collection and operation of the biogas plant in Solrød Municipality. It further entails studies of progress and evaluation reports from the municipality, analysis of seaweed digestion results from scholars connected to the research, as well as studies of scientific literature to supplement the above. Besides this, observations and photo documentation have been applied in the field. This paper concludes, among others, that the seaweed harvester technology currently adopted is functional in the maritime environment close to the beachfront but inadequate in collecting seaweed directly on the beach. New technology hence needs to be developed to increase the efficiency of seaweed collection. It is further concluded that the amount of sand transported to Solrød Biogas Plant with the seaweed continues to pose challenges. The seaweed is pre-treated for sand in a receiving tank with a strong stirrer, washing off the sand, which ends at the bottom of the tank where collected. The seaweed is then chopped by a macerator and mixed with the other feedstock. The wear down of the receiving tank stirrer and the chopper are, however, significant, and new methods should be adopted.

Keywords: biogas, circular bio-economy, Denmark, maritime technology, cast seaweed, solrød municipality

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Authors: Adrian Szczyrba, Aneta Halka-Grysinska, Tomasz Baj, Tadeusz H. Dzido

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Since prehistory, plants were constituted as an essential source of biologically active substances in folk medicine. One of the examples of medicinal plants is Ruta graveolens L. For a long time, Ruta g. herb has been famous for its spasmolytic, diuretic, or anti-inflammatory therapeutic effects. The wide spectrum of secondary metabolites produced by Ruta g. includes flavonoids (eg. rutin, quercetin), coumarins (eg. bergapten, umbelliferone) phenolic acids (eg. rosmarinic acid, chlorogenic acid), and limonoids. Unfortunately, the presence of produced substances is highly dependent on environmental factors like temperature, humidity, or soil acidity; therefore standardization is necessary. There were many attempts of characterization of various phytochemical groups (eg. coumarins) of Ruta graveolens using the normal – phase thin-layer chromatography (TLC). However, due to the so-called general elution problem, usually, some components remained unseparated near the start or finish line. Therefore Ruta graveolens is a very good model plant. Methanol and petroleum ether extract from its aerial parts were used to demonstrate the capabilities of the new device for gradient thin-layer chromatogram development. The development of gradient thin-layer chromatograms in the reversed-phase system in conventional horizontal chambers can be disrupted by problems associated with an excessive flux of the mobile phase to the surface of the adsorbent layer. This phenomenon is most likely caused by significant differences between the surface tension of the subsequent fractions of the mobile phase. An excessive flux of the mobile phase onto the surface of the adsorbent layer distorts the flow of the mobile phase. The described effect produces unreliable, and unrepeatable results, causing blurring and deformation of the substance zones. In the prototype device, the mobile phase solution is delivered onto the surface of the adsorbent layer with controlled velocity (by moving pipette driven by 3D machine). The delivery of the solvent to the adsorbent layer is equal to or lower than that of conventional development. Therefore chromatograms can be developed with optimal linear mobile phase velocity. Furthermore, under such conditions, there is no excess of eluent solution on the surface of the adsorbent layer so the higher performance of the chromatographic system can be obtained. Directly feeding the adsorbent layer with eluent also enables to perform convenient continuous gradient elution practically without the so-called gradient delay. In the study, unique fingerprints of methanol and petroleum ether extracts of Ruta graveolens aerial parts were obtained with stepwise gradient reversed-phase thin-layer chromatography. Obtained fingerprints under different chromatographic conditions will be compared. The advantages and disadvantages of the proposed approach to chromatogram development with controlled solvent velocity will be discussed.

Keywords: fingerprints, gradient thin-layer chromatography, reversed-phase TLC, Ruta graveolens

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Authors: Reshu Yadav, Himanshu Joshi, S. K. Tripathi

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Fresh water is a scarce resource which is essential for humans and ecosystems, but its distribution is uneven. Agricultural production accounts for 70% of all surface water supplies. It is projected that against the expansion in the area equipped for irrigation by 0.6% per year, the global potential irrigation water demand would rise by 9.5% during 2021-25. This would, on one hand, have to compete against the sharply rising urban water demand. On the other, it would also have to face the fear of climate change, as temperatures rise and crop yields could drop from 10-30% in many large areas. The huge demand for irrigation combined with fresh water scarcity encourages to explore the reuse of wastewater as a resource. However, the use of such wastewater is often linked to the safety issues when used non judiciously or with poor safeguards while irrigating food crops. Paddy is one of the major crops globally and amongst the most important in South Asia and Africa. In many parts of the world, use of municipal wastewater has been promoted as a viable option in this regard. In developing and fast growing countries like India, regularly increasing wastewater generation rates may allow this option to be considered quite seriously. In view of this, a pilot field study was conducted at the Jagjeetpur Municipal Sewage treatment plant situated in the Haridwar town of Uttarakhand state, India. The objectives of the present study were to study the effect of treated wastewater on the production of various paddy varieties (Sharbati, PR-114, PB-1, Menaka, PB1121 and PB 1509) and emission of GHG gases (CO2, CH4 and N2O) as compared to the same varieties grown in the control plots irrigated with fresh water. Of late, the concept of water footprint assessment has emerged, which explains enumeration of various types of water footprints of an agricultural entity from its production to processing stages. Paddy, the most water demanding staple crop of Uttarakhand state, displayed a high green water footprint value of 2966.538 m3/ton. Most of the wastewater irrigated varieties displayed upto 6% increase in production, except Menaka and PB-1121, which showed a reduction in production (6% and 3% respectively), due to pest and insect infestation. The treated wastewater was observed to be rich in Nitrogen (55.94 mg/ml Nitrate), Phosphorus (54.24 mg/ml) and Potassium (9.78 mg/ml), thus rejuvenating the soil quality and not requiring any external nutritional supplements. Percentage increase of GHG gases on irrigation with treated municipal waste water as compared to control plots was observed as 0.4% - 8.6% (CH4), 1.1% - 9.2% (CO2), and 0.07% - 5.8% (N2O). The variety, Sharbati, displayed maximum production (5.5 ton/ha) and emerged as the most resistant variety against pests and insects. The emission values of CH4 ,CO2 and N2O were 729.31 mg/m2/d, 322.10 mg/m2/d and 400.21 mg/m2/d in water stagnant condition. This study highlighted a successful possibility of reuse of wastewater for non-potable purposes offering the potential for exploiting this resource that can replace or reduce existing use of fresh water sources in agricultural sector.

Keywords: greenhouse gases, nutrients, water footprint, wastewater irrigation

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Authors: C. Silveira, A. Ascenso, J. Ferreira, A. I. Miranda, P. Tuccella, G. Curci

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Poor air quality is one of the main environmental causes of premature deaths worldwide, and mainly in cities, where the majority of the population lives. It is a consequence of successive land cover (LC) and use changes, as a result of the intensification of human activities. Knowing these landscape modifications in a comprehensive spatiotemporal dimension is, therefore, essential for understanding variations in air pollutant concentrations. In this sense, the use of air quality models is very useful to simulate the physical and chemical processes that affect the dispersion and reaction of chemical species into the atmosphere. However, the modelling performance should always be evaluated since the resolution of the input datasets largely dictates the reliability of the air quality outcomes. Among these data, the updated LC is an important parameter to be considered in atmospheric models, since it takes into account the Earth’s surface changes due to natural and anthropic actions, and regulates the exchanges of fluxes (emissions, heat, moisture, etc.) between the soil and the air. This work aims to evaluate the performance of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem), when different LC classifications are used as an input. The influence of two LC classifications was tested: i) the 24-classes USGS (United States Geological Survey) LC database included by default in the model, and the ii) CLC (Corine Land Cover) and specific high-resolution LC data for Portugal, reclassified according to the new USGS nomenclature (33-classes). Two distinct WRF-Chem simulations were carried out to assess the influence of the LC on air quality over Europe and Portugal, as a case study, for the year 2015, using the nesting technique over three simulation domains (25 km², 5 km² and 1 km² horizontal resolution). Based on the 33-classes LC approach, particular emphasis was attributed to Portugal, given the detail and higher LC spatial resolution (100 m x 100 m) than the CLC data (5000 m x 5000 m). As regards to the air quality, only the LC impacts on tropospheric ozone concentrations were evaluated, because ozone pollution episodes typically occur in Portugal, in particular during the spring/summer, and there are few research works relating to this pollutant with LC changes. The WRF-Chem results were validated by season and station typology using background measurements from the Portuguese air quality monitoring network. As expected, a better model performance was achieved in rural stations: moderate correlation (0.4 – 0.7), BIAS (10 – 21µg.m^-3) and RMSE (20 – 30 µg.m^-3), and where higher average ozone concentrations were estimated. Comparing both simulations, small differences grounded on the Leaf Area Index and air temperature values were found, although the high-resolution LC approach shows a slight enhancement in the model evaluation. This highlights the role of the LC on the exchange of atmospheric fluxes, and stresses the need to consider a high-resolution LC characterization combined with other detailed model inputs, such as the emission inventory, to improve air quality assessment.

Keywords: land use, spatial resolution, WRF-Chem, air quality assessment

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Authors: Elias Jemal Abdella

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The Blue Nile River is an important shared resource of Ethiopia, Sudan and also, because it is the major contributor of water to the main Nile River, Egypt. Despite the potential benefits of regional cooperation and integrated joint basin management, all three countries continue to pursue unilateral plans for development. Besides, there is great uncertainty about the likely impacts of climate change in water availability for existing as well as proposed irrigation and hydropower projects in the Blue Nile Basin. The main objective of this study is to quantitatively assess the impact of climate change on the hydrological regime of the upper Blue Nile basin, western Ethiopia. Three models were combined, a dynamic Coordinated Regional Climate Downscaling Experiment (CORDEX) regional climate model (RCM) that is used to determine climate projections for the Upper Blue Nile basin for Representative Concentration Pathways (RCPs) 4.5 and 8.5 greenhouse gas emissions scenarios for the period 2021-2050. The outputs generated from multimodel ensemble of four (4) CORDEX-RCMs (i.e., rainfall and temperature) were used as input to a Soil and Water Assessment Tool (SWAT) hydrological model which was setup, calibrated and validated with observed climate and hydrological data. The outputs from the SWAT model (i.e., projections in river flow) were used as input to a Water Evaluation and Planning (WEAP) water resources model which was used to determine the water resources implications of the changes in climate. The WEAP model was set-up to simulate three development scenarios. Current Development scenario was the existing water resource development situation, Medium-term Development scenario was planned water resource development that is expected to be commissioned (i.e. before 2025) and Long-term full Development scenario were all planned water resource development likely to be commissioned (i.e. before 2050). The projected change of mean annual temperature for period (2021 – 2050) in most of the basin are warmer than the baseline (1982 -2005) average in the range of 1 to 1.4oC, implying that an increase in evapotranspiration loss. Subbasins which already distressed from drought may endure to face even greater challenges in the future. Projected mean annual precipitation varies from subbasin to subbasin; in the Eastern, North Eastern and South western highland of the basin a likely increase of mean annual precipitation up to 7% whereas in the western lowland part of the basin mean annual precipitation projected to decrease by 3%. The water use simulation indicates that currently irrigation demand in the basin is 1.29 Bm3y-1 for 122,765 ha of irrigation area. By 2025, with new schemes being developed, irrigation demand is estimated to increase to 2.5 Bm3y-1 for 277,779 ha. By 2050, irrigation demand in the basin is estimated to increase to 3.4 Bm3y-1 for 372,779 ha. The hydropower generation simulation indicates that 98 % of hydroelectricity potential could be produced if all planned dams are constructed.

Keywords: Blue Nile River, climate change, hydropower, SWAT, WEAP

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Authors: Neusa Fernanda Torres, Buyisile Chibi, Lyn E. Middleton, Vernon P. Solomon, Tivani P. Mashamba-Thompson

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Background: Self-medication with antibiotics (SMA) is a global concern, with a higher incidence in low and middle-income countries (LMICs). Despite intense world-wide efforts to control and promote the rational use of antibiotics, continuing practices of SMA systematically exposes individuals and communities to the risk of antibiotic resistance and other undesirable antibiotic side effects. Moreover, it increases the health systems costs of acquiring more powerful antibiotics to treat the resistant infection. This review thus maps evidence on the factors influencing self-medication with antibiotics in these settings. Methods: The search strategy for this review involved electronic databases including PubMed, Web of Knowledge, Science Direct, EBSCOhost (PubMed, CINAHL with Full Text, Health Source - Consumer Edition, MEDLINE), Google Scholar, BioMed Central and World Health Organization library, using the search terms:’ Self-Medication’, ‘antibiotics’, ‘factors’ and ‘reasons’. Our search included studies published from 2007 to 2017. Thematic analysis was performed to identify the patterns of evidence on SMA in LMICs. The mixed method quality appraisal tool (MMAT) version 2011 was employed to assess the quality of the included primary studies. Results: Fifteen studies met the inclusion criteria. Studies included population from the rural (46,4%), urban (33,6%) and combined (20%) settings, of the following LMICs: Guatemala (2 studies), India (2), Indonesia (2), Kenya (1), Laos (1), Nepal (1), Nigeria (2), Pakistan (2), Sri Lanka (1), and Yemen (1). The total sample size of all 15 included studies was 7676 participants. The findings of the review show a high prevalence of SMA ranging from 8,1% to 93%. Accessibility, affordability, conditions of health facilities (long waiting, quality of services and workers) as long well as poor health-seeking behavior and lack of information are factors that influence SMA in LMICs. Antibiotics such as amoxicillin, metronidazole, amoxicillin/clavulanic, ampicillin, ciprofloxacin, azithromycin, penicillin, and tetracycline, were the most frequently used for SMA. The major sources of antibiotics included pharmacies, drug stores, leftover drugs, family/friends and old prescription. Sore throat, common cold, cough with mucus, headache, toothache, flu-like symptoms, pain relief, fever, running nose, toothache, upper respiratory tract infections, urinary symptoms, urinary tract infection were the common disease symptoms managed with SMA. Conclusion: Although the information on factors influencing SMA in LMICs is unevenly distributed, the available information revealed the existence of research evidence on antibiotic self-medication in some countries of LMICs. SMA practices are influenced by social-cultural determinants of health and frequently associated with poor dispensing and prescribing practices, deficient health-seeking behavior and consequently with inappropriate drug use. Therefore, there is still a need to conduct further studies (qualitative, quantitative and randomized control trial) on factors and reasons for SMA to correctly address the public health problem in LMICs.

Keywords: antibiotics, factors, reasons, self-medication, low and middle-income countries (LMICs)

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Authors: Silvia Baralla, Raffaella Zucaro, Romina Lorenzetti

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Water management needs to cope with economic, societal, and environmental changes. This could be guaranteed through 'shifting from government to governance'. In the last decades, it was applied in Europe through and within important legislative pillars (Water Framework Directive and Common Agricultural Policy) and their measures focused on resilience and adaptation to climate change, with particular attention to the creation of synergies among policies and all the actors involved at different levels. Within the climate change context, the agricultural sector can play, through sustainable water management, a leading role for climate-resilient growth and environmental integrity. A recent analysis on the water management governance of different countries identified some common gaps dealing with administrative, policy, information, capacity building, funding, objective, and accountability. The ability of a country to fill these gaps is an essential requirement to make some of the changes requested by Europe, in particular the improvement of the agro-ecosystem resilience to the effect of climatic change, supporting green and digital transitions, and sustainable water use. This research aims to contribute in sharing examples of water governances and related advantages useful to fill the highlighted gaps. Italy has developed a strong and exhaustive model of water governance in order to react with strategic and synergic actions since it is one of the European countries most threatened by climate change and its extreme events (drought, floods). In particular, the Italian water governance model was able to overcome several gaps, specifically as concerns the water use in agriculture, adopting strategies as a systemic/integrated approach, the stakeholder engagement, capacity building, the improvement of planning and monitoring ability, and an adaptive/resilient strategy for funding activities. They were carried out, putting in place regulatory, structural, and management actions. Regulatory actions include both the institution of technical committees grouping together water decision-makers and the elaboration of operative manuals and guidelines by means of a participative and cross-cutting approach. Structural actions deal with the funding of interventions within European and national funds according to the principles of coherence and complementarity. Finally, management actions regard the introduction of operational tools to support decision-makers in order to improve planning and monitoring ability. In particular, two cross-functional and interoperable web databases were introduced: SIGRIAN (National Information System for Water Resources Management in Agriculture) and DANIA (National Database of Investments for Irrigation and the Environment). Their interconnection allows to support sustainable investments, taking into account the compliance about irrigation volumes quantified in SIGRIAN, ensuring a high level of attention on water saving, and monitoring the efficiency of funding. Main positive results from the Italian water governance model deal with a synergic and coordinated work at the national, regional, and local level among institutions, the transparency on water use in agriculture, a deeper understanding from the stakeholder side of the importance of their roles and of their own potential benefits and the capacity to guarantee continuity to this model, through a sensitization process and the combined use of management operational tools.

Keywords: agricultural sustainability, governance model, water management, water policies

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Authors: Chandan Kundu, Sankar Bhattacharya

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A significant disadvantage of fossil fuel energy production is the considerable amount of carbon dioxide (CO₂) released, which is one of the contributors to climate change. Apart from environmental concerns, changing fossil fuel prices have pushed society gradually towards renewable energy sources in recent years. Biomass is a plentiful and renewable resource and a source of carbon. Recent years have seen increased research interest in generating fuels and chemicals from biomass. Unlike fossil-based resources, biomass is composed of lignocellulosic material, which does not contribute to the increase in atmospheric CO₂ over a longer term. These considerations contribute to the current move of the chemical industry from non-renewable feedstock to renewable biomass. This presentation focuses on generating bio-oil and two major platform chemicals that can potentially improve the environment. Thermochemical processes such as pyrolysis are considered viable methods for producing bio-oil and biomass-based platform chemicals. Fluidized bed reactors, on the other hand, are known to boost bio-oil yields during pyrolysis due to their superior mixing and heat transfer features, as well as their scalability. This review and the associated experimental work are focused on the thermochemical conversion of biomass to bio-oil and two high-value platform chemicals, Levoglucosenone (LGO) and 5-Chloromethyl furfural (5-CMF), in a fluidized bed reactor. These two active molecules with distinct features can potentially be useful monomers in the chemical and pharmaceutical industries since they are well adapted to the manufacture of biologically active products. This process took several meticulous steps. To begin, the biomass was delignified using a peracetic acid pretreatment to remove lignin. Because of its complicated structure, biomass must be pretreated to remove the lignin, increasing access to the carbohydrate components and converting them to platform chemicals. The biomass was then characterized by Thermogravimetric analysis, Synchrotron-based THz spectroscopy, and in-situ DRIFTS in the laboratory. Based on the results, a continuous-feeding fluidized bed reactor system was constructed to generate platform chemicals from pretreated biomass using hydrogen chloride acid-gas as a catalyst. The procedure also yields biochar, which has a number of potential applications, including soil remediation, wastewater treatment, electrode production, and energy resource utilization. Consequently, this research also includes a preliminary experimental evaluation of the biochar's prospective applications. The biochar obtained was evaluated for its CO₂ and steam reactivity. The outline of the presentation will comprise the following: Biomass pretreatment for effective delignification Mechanistic study of the thermal and thermochemical conversion of biomass Thermochemical conversion of untreated and pretreated biomass in the presence of an acid catalyst to produce LGO and CMF A thermo-catalytic process for the production of LGO and 5-CMF in a continuously-fed fluidized bed reactor and efficient separation of chemicals Use of biochar generated from the platform chemicals production through gasification

Keywords: biomass, pretreatment, pyrolysis, levoglucosenone

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Authors: Laura Villamizar, David Wright, Claudia Baena, Marie Foxwell, Maureen O'Callaghan

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Leguminous crops can be self-sufficient for their nitrogen requirements when their roots are nodulated with an effective Rhizobium strain and for this reason seed or soil inoculation is practiced worldwide to ensure nodulation and nitrogen fixation in grain and forage legumes. The most widely used method of applying commercially available inoculants is using peat cultures which are coated onto seeds prior to sowing. In general, rhizobia survive well in peat, but some species die rapidly after inoculation onto seeds. The development of improved formulation methodology is essential to achieve extended persistence of rhizobia on seeds, and improved efficacy. Formulations could be solid or liquid. Most popular solid formulations or delivery systems are: wettable powders (WP), water dispersible granules (WG), and granules (DG). Liquid formulation generally are: suspension concentrates (SC) or emulsifiable concentrates (EC). In New Zealand, R. leguminosarum bv. trifolii strain TA1 has been used as a commercial inoculant for white clover over wide areas for many years. Seeds inoculation is carried out by mixing the seeds with inoculated peat, some adherents and lime, but rhizobial populations on stored seeds decline over several weeks due to a number of factors including desiccation and antibacterial compounds produced by the seeds. In order to develop a more stable and suitable delivery system to incorporate rhizobia in pastures, two strains of R. leguminosarum (TA1 and CC275e) and several formulations and processes were explored (peat granules, self-sticky peat for seed coating, emulsions and a powder containing spray dried microcapsules). Emulsions prepared with fresh broth of strain TA1 were very unstable under storage and after seed inoculation. Formulations where inoculated peat was used as the active ingredient were significantly more stable than those prepared with fresh broth. The strain CC275e was more tolerant to stress conditions generated during formulation and seed storage. Peat granules and peat inoculated seeds using strain CC275e maintained an acceptable loading of 108 CFU/g of granules or 105 CFU/g of seeds respectively, during six months of storage at room temperature. Strain CC275e inoculated on peat was also microencapsulated with a natural biopolymer by spray drying and after optimizing operational conditions, microparticles containing 107 CFU/g and a mean particle size between 10 and 30 micrometers were obtained. Survival of rhizobia during storage of the microcapsules is being assessed. The development of a stable product depends on selecting an active ingredient (microorganism), robust enough to tolerate some adverse conditions generated during formulation, storage, and commercialization and after its use in the field. However, the design and development of an adequate formulation, using compatible ingredients, optimization of the formulation process and selecting the appropriate delivery system, is possibly the best tool to overcome the poor survival of rhizobia and provide farmers with better quality inoculants to use.

Keywords: formulation, Rhizobium leguminosarum, storage stability, white clover

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Authors: Jovana Grahovac, Ivana Pajcin, Natasa Lukic, Jelena Dodic, Aleksandar Jokic

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To obtain purified biomass to be used in the plant pathogen biocontrol or as soil biofertilizer, it is necessary to eliminate residual broth components at the end of the fermentation process. The main drawback of membrane separation techniques is permeate flux decline due to the membrane fouling. Fouling mitigation measures increase the pressure drop along membrane channel due to the increased resistance to flow of the feed suspension, thus increasing the hydraulic power drop. At the same time, these measures lead to an increase in the permeate flux due to the reduced resistance of the filtration cake on the membrane surface. Because of these opposing effects, the energy efficiency of fouling mitigation measures is limited, and the justification of its application is provided by information on a reducing specific energy consumption compared to a case without any measures employed. In this study, the influence of static mixer (Kenics) and air-sparging (two-phase flow) on reduction of specific energy consumption (ER) was investigated. Cultivation Bacillus velezensis was carried out in the 3-L bioreactor (Biostat® Aplus) containing 2 L working volume with two parallel Rushton turbines and without internal baffles. Cultivation was carried out at 28 °C on at 150 rpm with an aeration rate of 0.75 vvm during 96 h. The experiments were carried out in a conventional cross-flow microfiltration unit. During experiments, permeate and retentate were recycled back to the broth vessel to simulate continuous process. The single channel ceramic membrane (TAMI Deutschland) used had a nominal pore size 200 nm with the length of 250 mm and an inner/external diameter of 6/10 mm. The useful membrane channel surface was 4.33×10⁻³ m². Air sparging was brought by the pressurized air connected by a three-way valve to the feed tube by a simple T-connector without diffusor. The different approaches to flux improvement are compared in terms of energy consumption. Reduction of specific energy consumption compared to microfiltration without fouling mitigation is around 49% and 63%, for use of two-phase flow and a static mixer, respectively. In the case of a combination of these two fouling mitigation methods, ER is 60%, i.e., slightly lower compared to the use of turbulence promoter alone. The reason for this result can be found in the fact that flux increase is more affected by the presence of a Kenics static mixer while sparging results in an increase of energy used during microfiltration. By comparing combined method with turbulence promoter flux enhancement method ER is negative (-7%) which can be explained by increased power consumption for air flow with moderate contribution to the flux increase. Another confirmation for this fact can be found by comparing energy consumption values for combined method with energy consumption in the case of two-phase flow. In this instance energy reduction (ER) is 22% that demonstrates that turbulence promoter is more efficient compared to two phase flow. Antimicrobial activity of Bacillus velezensis biomass against phytopathogenic isolates Xanthomonas campestris was preserved under different fouling reduction methods.

Keywords: Bacillus velezensis, microfiltration, static mixer, two-phase flow

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Authors: Alvaro Valera Sosa

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Background: In recent years, childhood overweight and obesity have become an increasing and challenging phenomenon in Berlin and Germany in general. The highest shares of childhood overweight in Berlin are district localities within the inner city ring with lowest socio-economic levels and the highest number of migration background populations. Most factors explaining overweight and obesity are linked to individual dispositions and nutrition balances. Among various strategies, to target drinking behaviors of children and adolescents has been proven to be effective. On the one hand, encouraging the intake of water – which does not contain energy and thus may support a healthy weight status – on the other hand, reducing the consumption of sugar-containing beverages – which are linked to weight gain and obesity. Anyhow, these preventive approaches have mostly developed into individual or educational interventions widely neglecting environmental modifications. Therefore, little is known on how urban physical environment patterns and features can act as influence factors for childhood overweight. Aiming the development of a physical environment intervention tackling children overweight, this study evaluated urban situations surrounding public playgrounds in Berlin where the issue is evident. It verified the presence and state of physical environmental conditions that can be conducive for children to engage physical activity and water intake. Methods: The study included public playgrounds for children from 0-12 y/o within district localities with the highest prevalence of childhood overweight, highest population density, and highest mixed uses. A systematic observation was realized to describe physical environment patterns and features that may affect children health behavior leading to overweight. Neighborhood walkability for all age groups was assessed using the Walkability for Health framework (TU-Berlin). Playground physical environment conditions were evaluated using Active Living Research assessment sheets. Finally, the food environment in the playground’s pedestrian catchment areas was reviewed focusing on: proximity to suppliers offering sugar-containing beverages, and physical access for 5 y/o children and up to drinking water following the Drinking Fountains and Public Health guidelines of the Pacific Institute. Findings: Out of 114 locations, only 7 had a child population over 3.000. Three with the lowest socio-economic index and highest percentage of migration background were selected. All three urban situations presented similar walkability: large trafficked avenues without buffer bordering at least one side of the playground, and important block to block disconnections for active travel. All three playgrounds rated equipment conditions from good to very good. None had water fountains at the reach of a 5 y/o. and all presented convenience stores and/or fast food outlets selling sugar-containing beverages nearby the perimeter. Conclusion: The three playground situations selected are representative of Berlin locations where most factors that influence children overweight are found. The results delivered urban and architectural design directives for an environmental intervention, used to study children health-related behavior. A post-intervention evaluation could prove associations between designed spaces and children overweight rate reduction creating a precedent in public health interventions and providing novel strategies for the health sector.

Keywords: children overweight, evaluation research, public playgrounds, urban design, urban health

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Authors: Amrei Voelkner, Nils Peters, Thomas Mannheim

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The worldwide exponential growth of the population and the simultaneous increasing food production requires the strategic realization of sustainable and improved cultivation systems to ensure the fertility of arable land and to guarantee the food supply for the whole world. To fulfill this target, large quantities of fertilizers have to be applied to the field, but the long-term environmental impacts remain uncertain. Thus, a combined system would be necessary to increase the nutrient availability for plants while reducing nutrient losses (e.g. NO3- by leaching) to the environment. To enhance the nutrient efficiency, polymer coated fertilizer with a controlled release behavior have been developed. This kind of fertilizer ensures a delayed release of nutrients to synchronize the nutrient supply with the demand of different crops. In the last decades, research focused primarily on semi-permeable polyurethane coatings, which remain in the soil for a long period after the complete solvation of the fertilizer core. Within the implementation of the new European Regulation Directive the replacement of non-degradable synthetic polymers by degradable coatings is necessary. It was, therefore, the objective of this study to develop a total biodegradable polymer (to CO2 and H2O) coating according to ISO 17556 and to compare the retarding effect of the biodegradable coatings with commercially available non-degradable products. To investigate the effect of ten selected coated urea fertilizer on the yield of annual ryegrass and maize, the fresh and dry mass, the percentage of total nitrogen and main nutrients were analyzed in greenhouse experiments in sixfold replications using near-infrared spectroscopy. For the experiments, a homogenized and air-dried loamy sand (Cambic Luvisol) was equipped with a basic fertilization of P, K, Mg and S. To investigate the effect of nitrogen level increase, three levels (80%, 100%, 120%) were established, whereas the impact of CRF granules was determined using a N-level of 100%. Additionally, leaching of NO3- from pots planted with annual ryegrass was examined to evaluate the retention capacity of urea by the polymer coating. For this, leachate from Kick-Brauckmann-Pots was collected daily and analyzed for total nitrogen, NO3- and NH4+ in twofold repetition once a week using near-infrared spectroscopy. We summarize from the results that the coated fertilizer have a clear impact on the yield of annual ryegrass and maize. Compared to the control, an increase of fresh and dry mass could be recognized. Partially, the non-degradable coatings showed a retarding effect for a longer period, which was however reflected by a lower fresh and dry mass. It was ascertained that the percentage of leached-out nitrate could be reduced markedly. As a conclusion, it could be pointed out that the impact of coated fertilizer of all polymer types might contribute to a reduction of negative environmental impacts in addition to their fertilizing effect.

Keywords: biodegradable polymers, coating, enhanced efficiency fertilizers, nitrate leaching

Procedia PDF Downloads 249

Authors: Filip Varga, Nina Jeran, Martina Biosic, Zlatko Satovic, Martina Grdisa

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Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip.), a species endemic to the eastern Adriatic coastline, is the source of natural insecticide pyrethrin. Pyrethrin is a mixture of six compounds (pyrethrin I and II, cinerin I and II, jasmolin I and II) that exhibits high insecticidal activity with no detrimental effects to the environment. A recently optimized matrix-solid phase dispersion method (MSPD), using florisil as the sorbent, acetone-ethyl acetate (1:1, v/v) as the elution solvent, and sodium sulfate anhydrous as the drying agent was utilized to extract the pyrethrins from 10 wild populations (20 individuals per population) distributed along the Croatian coast. All six components in the extracts were qualitatively and quantitatively determined by high-performance liquid chromatography with a diode array detector (HPLC-DAD). Pearson’s correlation index was calculated between pyrethrin compounds, and differences between the populations using the analysis of variance were tested. Additionally, the correlation of each pyrethrin component with spatio-ecological variables (bioclimate, soil properties, elevation, solar radiation, and distance from the coastline) was calculated. Total pyrethrin content ranged from 0.10% to 1.35% of dry flower weight, averaging 0.58% across all individuals. Analysis of variance revealed significant differences between populations based on all six pyrethrin compounds and total pyrethrin content. On average, the lowest total pyrethrin content was found in the population from Pelješac peninsula (0.22% of dry flower weight) in which total pyrethrin content lower than 0.18% was detected in 55% of the individuals. The highest average total pyrethrin content was observed in the population from island Zlarin (0.87% of dry flower weight), in which total pyrethrin content higher than 1.00% was recorded in only 30% of the individuals. Pyrethrin I/pyrethrin II ratio as a measure of extract quality ranged from 0.21 (population from the island Čiovo) to 5.88 (population from island Mali Lošinj) with an average of 1.77 across all individuals. By far, the lowest quality of extracts was found in the population from Mt. Biokovo (pyrethrin I/II ratio lower than 0.72 in 40% of individuals) due to the high pyrethrin II content typical for this population. Pearson’s correlation index revealed a highly significant positive correlation between pyrethrin I content and total pyrethrin content and a strong negative correlation between pyrethrin I and pyrethrin II. The results of this research clearly indicate high intra- and interpopulation diversity of Dalmatian pyrethrum with regards to pyrethrin content and composition. The information obtained has potential use in plant genetic resources conservation and biodiversity monitoring. Possibly the largest potential lies in designing breeding programs aimed at increasing pyrethrin content in commercial breeding lines and reintroduction in agriculture in Croatia. Acknowledgment: This work has been fully supported by the Croatian Science Foundation under the project ‘Genetic background of Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir/ Sch. Bip.) insecticidal potential’ - (PyrDiv) (IP-06-2016-9034).

Keywords: Dalmatian pyrethrum, HPLC, MSPD, pyrethrin

Procedia PDF Downloads 114

Authors: Andrés Quiroz, Emilio Hormazábal, Ana Mutis, Fernando Ortega, Loreto Méndez, Leonardo Parra

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Red clover root borer, Hylastinus obscurus Marsham (Coleoptera: Curculionidae), is the main insect pest associated to red clover, Trifolium pratense L. An average of 1.5 H. obscurus per plant can cause 5.5% reduction in forage yield in pastures of two to three years old. Moreover, insect attack can reach 70% to 100% of the plants. To our knowledge, there is no a chemical strategy for controlling this pest. Therefore alternative strategies for controlling H. obscurus are a high priority for red clover producers. One of this alternative is related to the study of secondary metabolites involved in intrinsic chemical defenses developed by plants, such as isoflavonoids. The isoflavonoids formononetin and daidzein have elicited an antifeedant and phagostimult effect on H. obscurus respectively. However, we do not know how is the dynamic variation of these isoflavonoids under field conditions. The main objective of this work was to evaluate the variation of the antifeedant isoflavonoids formononetin, the phagostimulant isoflavonoids daidzein, and their respective glycosides over time in different ecotypes of red clover. Fourteen red clover ecotypes (8 cultivars and 6 experimental lines), were collected at INIA-Carillanca (La Araucanía, Chile). These plants were established in October 2015 under irrigated conditions. The cultivars were distributed in a randomized complete block with three replicates. The whole plants were sampled in four times: 15th October 2016, 12th December 2016, 27th January 2017 and 16th March 2017 with sufficient amount of soil to avoid root damage. A polar fraction of isoflavonoid was obtained from 20 mg of lyophilized root tissue extracted with 2 mL of 80% MeOH for 16 h using an orbital shaker in the dark at room temperature. After, an aliquot of 1.4 mL of the supernatant was evaporated, and the residue was resuspended in 300 µL of 45% MeOH. The identification and quantification of isoflavonoid root extracts were performed by the injection of 20 µL into a Shimadzu HPLC equipped with a C-18 column. The sample was eluted with a mobile phase composed of AcOH: H₂O (1:9 v/v) as solvent A and CH₃CN as solvent B. The detection was performed at 260 nm. The results showed that the amount of aglycones was higher than the respective glycosides. This result is according to the biosynthetic pathway of flavonoids, where the formation of glycoside is further to the glycosides biosynthesis. The amount of formononetin was higher than daidzein. In roots, where H. obscurus spent the most part of its live cycle, the highest content of formononetin was found in G 27, Pawera, Sabtoron High, Redqueli-INIA and Superqueli-INIA cvs. (2.1, 1.8, 1.8, 1.6 and 1.0 mg g⁻¹ respectively); and the lowest amount of daidzein were found Superqueli-INIA (0.32 mg g⁻¹) and in the experimental line Sel Syn Int4 (0.24 mg g⁻¹). This ecotype showed a high content of formononetin (0.9 mg g⁻¹). This information, associated with cultural practices, could help farmers and breeders to reduce H. obscurus in grassland, selecting ecotypes with high content of formononetin and low amount of daidzein in the roots of red clover plants. Acknowledgements: FONDECYT 1141245 and 11130715.

Keywords: daidzein, formononetin, isoflavonoid glycosides, trifolium pratense

Procedia PDF Downloads 188

Authors: Salam N. Abdo, Orien L. Tulp, George P. Einstein

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The purpose of this exploratory study was to gather the insights into psoriasis etiology, treatment, and patient experience, for developing psoriasis and psoriatic arthritis diagnostic test. Data collection methods consisted of a comprehensive meta-analysis of relevant studies and psoriasis patient survey. Established meta-analysis guidelines were used for the selection and qualitative comparative analysis of psoriasis and psoriatic arthritis research studies. Only studies that clearly discussed psoriasis etiology, treatment, and patient experience were reviewed and analyzed, to establish a qualitative data base for the study. Using the insights gained from meta-analysis, an existing psoriasis patient survey was modified and administered to collect additional data as well as triangulate the results. The hypothesis is that specific types of psoriatic disease have specific etiology and pathophysiologic pattern. The following etiology categories were identified: bacterial, environmental/microbial, genetic, immune, infectious, trauma/stress, and viral. Additional results, obtained from meta-analysis and confirmed by patient survey, were the common age of onset (early to mid-20s) and type of psoriasis (plaque; mild; symmetrical; scalp, chest, and extremities, specifically elbows and knees). Almost 70% of patients reported no prescription drug use due to severe side effects and prohibitive cost. These results will guide the development of psoriasis and psoriatic arthritis diagnostic test. The significant number of medical publications classified psoriatic arthritis disease as inflammatory of an unknown etiology. Thus numerous meta-analyses struggle to report any meaningful conclusions since no definitive results have been reported to date. Therefore, return to the basics is an essential step to any future meaningful results. To date, medical literature supports the fact that psoriatic disease in its current classification could be misidentifying subcategories, which in turn hinders the success of studies conducted to date. Moreover, there has been an enormous commercial support to pursue various immune-modulation therapies, thus following a narrow hypothesis/mechanism of action that is yet to yield resolution of disease state. Recurrence and complications may be considered unacceptable in a significant number of these studies. The aim of the ongoing study is to focus on a narrow subgroup of patient population, as identified by this exploratory study via meta-analysis and patient survey, and conduct an exhaustive work up, aiming at mechanism of action and causality before proposing a cure or therapeutic modality. Remission in psoriasis has been achieved and documented in medical literature, such as immune-modulation, phototherapy, various over-the-counter agents, including salts and tar. However, there is no psoriasis and psoriatic arthritis diagnostic test to date, to guide the diagnosis and treatment of this debilitating and, thus far, incurable disease. Because psoriasis affects approximately 2% of population, the results of this study may affect the treatment and improve the quality of life of a significant number of psoriasis patients, potentially millions of patients in the United States alone and many more millions worldwide.

Keywords: biologics, early diagnosis, etiology, immune disease, immune modulation therapy, inflammation skin disorder, phototherapy, plaque psoriasis, psoriasis, psoriasis classification, psoriasis disease marker, psoriasis diagnostic test, psoriasis marker, psoriasis mechanism of action, psoriasis treatment, psoriatic arthritis, psoriatic disease, psoriatic disease marker, psoriatic patient experience, psoriatic patient quality of life, remission, salt therapy, targeted immune therapy

Procedia PDF Downloads 97

Authors: R. S. Giraddi, B. Thirupam Reddy, D. N. Kambrekar

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Chilli (Capsicum annum L.) an important commercial vegetable crop is ravaged by a number of insect-pests during both vegetative and reproductive phase resulting into significant crop loss.Thrips, Scirtothripsdorsalis, mite, Polyphagotarsonemuslatus and whitefly, Bemisiatabaci are the key sap feeding insects, their infestation leads to leaf curl, stunted growth and yield loss.During flowering and fruit formation stage, gall midge fly, Asphondyliacapparis (Rubsaaman) infesting flower buds and young fruits andHelicoverpaarmigera (Hubner) feeding on matured green fruits are the important insect pests causing significant crop loss.The pest is known to infest both flower buds and young fruits resulting into malformation of flower buds and twisting of fruits.In order to manage these insect-pests a combi product consisting of imidacloprid and betacyfluthrin (Soloman 300 OD) was evaluated for its bio-efficacy, phytotoxicity and effect on predator activity.Imidacloprid, a systemic insecticide belonging to neo-nicotinoid group, is effective against insect pests such as aphids, whiteflies (sap feeders) and other insectsviz., termites and soil insects.Beta-Cyfluthrin is an insecticide of synthetic pyrethroid group which acts by contact action and ingestion. It acts on the insects' nervous system as sodium channel blocker consequently a disorder of the nervous system occurs leading finally to the death. The field experiments were taken up during 2015 and 2016 at the Main Agricultural Research Station of University of Agricultural Sciences, Dharwad, Karnataka, India.The trials were laid out in a Randomized Block Design (RBD) with three replications using popular land race of Byadagi crop variety.Results indicated that the product at 21.6 + 50.4% gai/ha (240 ml/ha) and 27.9 + 65% gai/ha (310 ml/ha) was found quite effective in controlling thrips (0.00 to 0.66 thrips per six leaves) as against the standard check insecticide recommended for thrips by the University of Agricultural Sciences, Dharwad wherein the density of thrips recorded was significantly higher (1.00 to 2.00 Nos./6 leaves). Similarly, the test insecticide was quite effective against other target insects, whiteflies, fruit borer and gall midge fly as indicated by lower insect population observed in the treatments as compared to standard insecticidal control. The predatory beetle activity was found to be normal in all experimental plots. Highest green fruit yield of 5100-5500 kg/ha was recorded in Soloman 300 OD applied crop at 310 ml/ha rate as compared to 4750 to 5050 kg/ha recorded in check. At present 6-8 sprays of insecticides are recommended for management of these insect-pests on the crop. If combi-products are used in pest management programmes, it is possible to reduce insecticide usages in crop ecosystem.

Keywords: Imidacloprid, Betacyfluthrin, gallmidge fly, thrips, chilli

Procedia PDF Downloads 135

Authors: Zanele D. Ngwenya, Mustapha Mohammed, Felix D. Dakora

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Legumes are a major source of biological nitrogen, and therefore play a crucial role in maintaining soil productivity in smallholder agriculture in southern Africa. Through their ability to fix atmospheric nitrogen in root nodules, legumes are a better option for sustainable nitrogen supply in cropping systems than chemical fertilisers. For decades, farmers have been highly receptive to the use of rhizobial inoculants as a source of nitrogen due mainly to the availability of elite rhizobial strains at a much lower compared to chemical fertilisers. To improve the efficiency of the legume-rhizobia symbiosis in African soils would require the use of highly effective rhizobia capable of nodulating a wide range of host plants. This study assessed the morphogenetic diversity, photosynthetic functioning and relative symbiotic effectiveness (RSE) of groundnut, jack bean and soybean microsymbionts in Eswatini soils as a first step to identifying superior isolates for inoculant production. According to the manufacturer's instructions, rhizobial isolates were cultured in yeast-mannitol (YM) broth until the late log phase and the bacterial genomic DNA was extracted using GenElute bacterial genomic DNA kit. The extracted DNA was subjected to enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) and a dendrogram constructed from the band patterns to assess rhizobial diversity. To assess the N2-fixing efficiency of the authenticated rhizobia, photosynthetic rates (A), stomatal conductance (gs), and transpiration rates (E) were measured at flowering for plants inoculated with the test isolates. The plants were then harvested for nodulation assessment and measurement of plant growth as shoot biomass. The results of ERIC-PCR fingerprinting revealed the presence of high genetic diversity among the microsymbionts nodulating each of the three test legumes, with many of them showing less than 70% ERIC-PCR relatedness. The dendrogram generated from ERIC-PCR profiles grouped the groundnut isolates into 5 major clusters, while the jack bean and soybean isolates were grouped into 6 and 7 major clusters, respectively. Furthermore, the isolates also elicited variable nodule number per plant, nodule dry matter, shoot biomass and photosynthetic rates in their respective host plants under glasshouse conditions. Of the groundnut isolates tested, 38% recorded high relative symbiotic effectiveness (RSE >80), while 55% of the jack bean isolates and 93% of the soybean isolates recorded high RSE (>80) compared to the commercial Bradyrhizobium strains. About 13%, 27% and 83% of the top N₂-fixing groundnut, jack bean and soybean isolates, respectively, elicited much higher relative symbiotic efficiency (RSE) than the commercial strain, suggesting their potential for use in inoculant production after field testing. There was a tendency for both low and high N₂-fixing isolates to group together in the dendrogram from ERIC-PCR profiles, which suggests that RSE can differ significantly among closely related microsymbionts.

Keywords: genetic diversity, relative symbiotic effectiveness, inoculant, N₂-fixing

Procedia PDF Downloads 185

Authors: Muhammad Karim Ahmadzai

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Floods are natural phenomena and are an integral part of the water cycle. The majority of them are the result of climatic conditions, but are also affected by the geology and geomorphology of the area, topography and hydrology, the water permeability of the soil and the vegetation cover, as well as by all kinds of human activities and structures. However, from the moment that human lives are at risk and significant economic impact is recorded, this natural phenomenon becomes a natural disaster. Flood management is now a key issue at regional and local levels around the world, affecting human lives and activities. The majority of floods are unlikely to be fully predicted, but it is feasible to reduce their risks through appropriate management plans and constructions. The aim of this Case Study is to identify, and map areas of flood risk in the Khinch District of Panjshir Province, Afghanistan specifically in the area of Peshghore, causing numerous damages. The main purpose of this study is to evaluate the contribution of remote sensing technology and Geographic Information Systems (GIS) in assessing the susceptibility of this region to flood events. Panjsher is facing Seasonal floods and human interventions on streams caused floods. The beds of which have been trampled to build houses and hotels or have been converted into roads, are causing flooding after every heavy rainfall. The streams crossing settlements and areas with high touristic development have been intensively modified by humans, as the pressure for real estate development land is growing. In particular, several areas in Khinch are facing a high risk of extensive flood occurrence. This study concentrates on the construction of a flood susceptibility map, of the study area, by combining vulnerability elements, using the Analytical Hierarchy Process/ AHP. The Analytic Hierarchy Process, normally called AHP, is a powerful yet simple method for making decisions. It is commonly used for project prioritization and selection. AHP lets you capture your strategic goals as a set of weighted criteria that you then use to score projects. This method is used to provide weights for each criterion which Contributes to the Flood Event. After processing of a digital elevation model (DEM), important secondary data were extracted, such as the slope map, the flow direction and the flow accumulation. Together with additional thematic information (Landuse and Landcover, topographic wetness index, precipitation, Normalized Difference Vegetation Index, Elevation, River Density, Distance from River, Distance to Road, Slope), these led to the final Flood Risk Map. Finally, according to this map, the Priority Protection Areas and Villages and the structural and nonstructural measures were demonstrated to Minimize the Impacts of Floods on residential and Agricultural areas.

Keywords: flood hazard, flood risk map, flood mitigation measures, AHP analysis

Procedia PDF Downloads 90

Authors: Johns Paul, Santhosh J. Nalluveettil, P. Purushothaman, M. Premdas

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Lunar landing is one of the most critical phases of lunar mission. The lander is provided with a soft landing system to prevent structural damage of lunar module by absorbing the landing shock and also assure stability during landing. Presently available software are not capable to simulate the rigid body dynamics coupled with contact simulation and elastic/plastic deformation analysis. Hence a separate mathematical model has been generated for studying the dynamics of a typical lunar soft lander. Parameters used in the analysis includes lunar surface slope, coefficient of friction, initial touchdown velocity (vertical and horizontal), mass and moment of inertia of lander, crushing force due to energy absorbing material in the legs, number of legs and geometry of lander. The mathematical model is capable to simulate plastic and elastic deformation of honey comb, frictional force between landing leg and lunar soil, surface contact simulation, lunar gravitational force, rigid body dynamics and linkage dynamics of inverted tripod landing gear. The non linear differential equations generated for studying the dynamics of lunar lander is solved by numerical method. Matlab programme has been used as a computer tool for solving the numerical equations. The position of each kinematic joint is defined by mathematical equations for the generation of equation of motion. All hinged locations are defined by position vectors with respect to body fixed coordinate. The vehicle rigid body rotations and motions about body coordinate are only due to the external forces and moments arise from footpad reaction force due to impact, footpad frictional force and weight of vehicle. All these force are mathematically simulated for the generation of equation of motion. The validation of mathematical model is done by two different phases. First phase is the validation of plastic deformation of crushable elements by employing conservation of energy principle. The second phase is the validation of rigid body dynamics of model by simulating a lander model in ADAMS software after replacing the crushable elements to elastic spring element. Simulation of plastic deformation along with rigid body dynamics and contact force cannot be modeled in ADAMS. Hence plastic element of primary strut is replaced with a spring element and analysis is carried out in ADAMS software. The same analysis is also carried out using the mathematical model where the simulation of honeycomb crushing is replaced by elastic spring deformation and compared the results with ADAMS analysis. The rotational motion of linkages and 6 degree of freedom motion of lunar Lander about its CG can be validated by ADAMS software by replacing crushing element to spring element. The model is also validated by the drop test results of 4 leg lunar lander. This paper presents the details of mathematical model generated and its validation.

Keywords: honeycomb, landing leg tripod, lunar lander, primary link, secondary link

Procedia PDF Downloads 317

Authors: Yohana Fessehazion

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Mercury is a prominent example of a heavy metal contaminant in the environment, and it has been extensively investigated for its potential health risk in humans and other organisms. In South Africa, massive mercury contamination happened in1980s when the England-based mercury reclamation processing plant relocated to Cato Ridge, KwaZulu-Natal Province, and discharged mercury waste into the Mngceweni River. This mercury waste discharge resulted in high mercury concentration that exceeded the acceptable levels in Mngceweni River, Umgeni River, and human hair of the nearby villagers. This environmental issue raised the alarm, and over the years, several environmental assessments were reported the dire environmental crises resulting from the Thor Chemicals (now known as Metallica Chemicals) and urged the immediate removal of the around 3,000 tons of mercury waste stored in the factory storage facility over two decades. Recently theft of some containers with the toxic substance from the Thor Chemicals warehouse and the subsequent fire that ravaged the facility furtherly put the factory on the spot escalating the urgency of left behind deadly mercury waste removal. This project aims to investigate the mercury contamination leaking from an old Thor Chemicals mercury processing plant. The focus will be on sediments, water, terrestrial plants, and aquatic weeds such as the prominent water hyacinth weeds in the nearby water systems of Mngceweni River, Umgeni River, and Inanda Dam as a bio-indicator and phytoremediator for mercury pollution. Samples will be collected in spring around October when the condition is favourable for microbial activity to methylate mercury incorporated in sediments and blooming season for some aquatic weeds, particularly water hyacinth. Samples of soil, sediment, water, terrestrial plant, and aquatic weed will be collected per sample site from the point of source (Thor Chemicals), Mngceweni River, Umgeni River, and the Inanda Dam. One-way analysis of variance (ANOVA) tests will be conducted to determine any significant differences in the Hg concentration among all sampling sites, followed by Least Significant Difference post hoc test to determine if mercury contamination varies with the gradient distance from the source point of pollution. The flow injection atomic spectrometry (FIAS) analysis will also be used to compare the mercury sequestration between the different plant tissues (roots and stems). The principal component analysis is also envisaged for use to determine the relationship between the source of mercury pollution and any of the sampling points (Umgeni and Mngceweni Rivers and the Inanda Dam). All the Hg values will be expressed in µg/L or µg/g in order to compare the result with the previous studies and regulatory standards. Sediments are expected to have relatively higher levels of Hg compared to the soils, and aquatic macrophytes, water hyacinth weeds are expected to accumulate a higher concentration of mercury than terrestrial plants and crops.

Keywords: mercury, phytoremediation, Thor chemicals, water hyacinth

Procedia PDF Downloads 182

Authors: Luisa Müting, Wisnu Harto Adiwijoyo

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Agroforestry systems transform the agricultural landscapes in the Sahel region of Africa, providing food and farming products consumed for subsistence or sold for income. In the incrementally dry climate of the Sahel region, the spreading of agroforestry practices is integral for policymaker efforts to counteract land degradation and provide soil restoration in the region. Several measures on agroforestry practices have been implemented in the region by governmental and non-governmental institutions in recent years. However, despite the efforts, past research shows that awareness of how policies and interventions are being consumed and perceived by the public remains low. Therefore, interpreting public policy dilemmas by analyzing the public perception regarding agroforestry concepts and practices is necessary. Public perceptions and discourses can be an essential driver or constraint for the adoption of agroforestry practices in the region. Thus, understanding the public discourse behavior of crucial stakeholders could assist policymakers in developing inclusive and contextual policies that are relevant to the context of agroforestry adoption in Sahel region. To answer how information about agroforestry spreads and is perceived by the public. As internet usage increased drastically over the past decade, reaching a share of 33 percent of the population being connected to the internet, this research is based on online conversation data. Social media data from Facebook are gathered daily between April 2021 and April 2022 in Djibouti, Senegal, Mali, and Nigeria based on their share of active internet users compared to other countries in the Sahel region. A systematic methodology was applied to the extracted social media using discourse network analysis (DNA). This study then clustered the data by the types of agroforestry practices, sentiments, and country. Additionally, this research extracted the text data from online news media during the same period to pinpoint events related to the topic of agroforestry. The preliminary result indicates that tree management, crops, and livestock integration, diversifying species and genetic resources, and focusing on interactions and productivity across the agricultural system; are the most notable keywords in agroforestry-related conversations within the four countries in the Sahel region. Additionally, approximately 84 percent of the discussions were still dominated by big actors, such as NGO or government actors. Furthermore, as a subject of communication within agroforestry discourse, the Great Green Wall initiative generates almost 60 percent positive sentiment within the captured social media data, effectively having a more significant outreach than general agroforestry topics. This study provides an understanding for scholars and policymakers with a springboard for further research or policy design on agroforestry in the four countries of the Sahel region with systematically uncaptured novel data from the internet.

Keywords: sahel, djibouti, senegal, mali, nigeria, social networks analysis, public discourse analysis, sentiment analysis, content analysis, social media, online news, agroforestry, land restoration

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Authors: J. A. Sawicki, C. Ebrahimi

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The first geochemical, petrological, X-ray diffraction, Raman, Mössbauer, and oxygen isotopic analyses of very intriguing 13-kg Sooke #1 stone covered in 70% of its surface with black fusion crust, found in and recovered from Sooke Basin, near Juan de Fuca Strait, in British Columbia, were reported as poster #2775 at LPSC52 in March. Our further analyses reported in poster #6305 at 84AMMS in August and comparisons with the Mössbauer spectra of Martian meteorite MIL03346 and Martian rocks in Gusev Crater reported by Morris et al. suggest that Sooke #1 find could be a stony achondrite of Martian polymict breccia type ejected from early watery Mars. Here, the Raman spectra of a carbon-rich ~1-mm² fossil-like white area identified in this rock on a surface of polished cut have been examined in more detail. The low-intensity 532 nm and 633 nm beams of the InviaRenishaw microscope were used to avoid any destructive effects. The beam was focused through the microscope objective to a 2 m spot on a sample, and backscattered light collected through this objective was recorded with CCD detector. Raman spectra of dark areas outside fossil have shown bands of clinopyroxene at 320, 660, and 1020 cm-1 and small peaks of forsteritic olivine at 820-840 cm-1, in agreement with results of X-ray diffraction and Mössbauer analyses. Raman spectra of the white area showed the broad band D at ~1310 cm-1 consisting of main mode A1g at 1305 cm⁻¹, E2g mode at 1245 cm⁻¹, and E1g mode at 1355 cm⁻¹ due to stretching diamond-like sp3 bonds in diamond polytype lonsdaleite, as in Ovsyuk et al. study. The band near 1600 cm-1 mostly consists of D2 band at 1620 cm-1 and not of the narrower G band at 1583 cm⁻¹ due to E2g stretching in planar sp2 bonds that are fundamental building blocks of carbon allotropes graphite and graphene. In addition, the broad second-order Raman bands were observed with 532 nm beam at 2150, ~2340, ~2500, 2650, 2800, 2970, 3140, and ~3300 cm⁻¹ shifts. Second-order bands in diamond and other carbon structures are ascribed to the combinations of bands observed in the first-order region: here 2650 cm⁻¹ as 2D, 2970 cm⁻¹ as D+G, and 3140 cm⁻¹ as 2G ones. Nanodiamonds are abundant in the Universe, found in meteorites, interplanetary dust particles, comets, and carbon-rich stars. The diamonds in meteorites are presently intensely investigated using Raman spectroscopy. Such particles can be formed by CVD process and during major impact shocks at ~1000-2300 K and ~30-40 GPa. It cannot be excluded that the fossil discovered in Sooke #1 could be a remnant of an alien carbon organism that transformed under shock impact to nanodiamonds. We trust that for the benefit of research in astro-bio-geology of meteorites, asteroids, Martian rocks, and soil, this find deserves further, more thorough investigations. If possible, the Raman SHERLOCK spectrometer operating on the Perseverance Rover should also search for such objects in the Martian rocks.

Keywords: achondrite, nanodiamonds, lonsdaleite, raman spectra

Procedia PDF Downloads 123

Authors: Claudio Lamilla, Misael Riquelme, Victoria Saez, Fernanda Sepulveda, Monica Pavez, Leticia Barrientos

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Biosurfactants are compounds synthesized by microorganisms that show various chemical structures, including glycolipids, lipopeptides, polysaccharide-protein complex, phospholipids, and fatty acids. These molecules have attracted attention in recent years due to the amphipathic nature of these compounds, which allows their application in various activities related to emulsification, foaming, detergency, wetting, dispersion and solubilization of hydrophobic compounds. Microorganisms that produce biosurfactants are ubiquitous, not only present in water, soil, and sediments but in extreme conditions of pH, salinity or temperature such as those present in Antarctic ecosystems. Due to this, it is of interest to study biosurfactants producing bacterial strains isolated from Antarctic environments, with the potential to be used in various biotechnological processes. The objective of this research was to characterize biosurfactants produced by bacterial strains isolated from Antarctic environments, with potential use in biotechnological processes for the cleaning of sites contaminated with hydrocarbons. The samples were collected from soils and sediments in the South Shetland Islands and the Antarctic Peninsula, during the Antarctic Research Expedition INACH 2016, from both pristine and human occupied areas (influenced). The bacteria isolation was performed from solid R2A, M1 and LB media. The selection of strains producing biosurfactants was done by hemolysis test on blood agar plates (5%) and blue agar (CTAB). From 280 isolates, it was determined that 10 bacterial strains produced biosurfactants after stimulation with different carbon sources. 16S rDNA taxonomic markers, using the universal primers 27F-1492R, were used to identify these bacterias. Biosurfactants production was carried out in 250 ml flasks using Bushnell Hass liquid culture medium enriched with different carbon sources (olive oil, glucose, glycerol, and hexadecane) during seven days under constant stirring at 20°C. Each cell-free supernatant was characterized by physicochemical parameters including drop collapse, emulsification and oil displacement, as well as stability at different temperatures, salinity, and pH. In addition, the surface tension of each supernatant was quantified using a tensiometer. The strains with the highest activity were selected, and the production of biosurfactants was stimulated in six liters of culture medium. Biosurfactants were extracted from the supernatants with chloroform methanol (2:1). These biosurfactants were tested against crude oil and motor oil, to evaluate their displacement activity (detergency). The characterization by physicochemical properties of 10 supernatants showed that 80% of them produced the drop collapse, 60% had stability at different temperatures, and 90% had detergency activity in motor and olive oil. The biosurfactants obtained from two bacterial strains showed a high activity of dispersion of crude oil and motor oil with halos superior to 10 cm. We can conclude that bacteria isolated from Antarctic soils and sediments provide biological material of high quality for the production of biosurfactants, with potential applications in the biotechnological industry, especially in hydrocarbons -contaminated areas such as petroleum.

Keywords: antarctic, bacteria, biosurfactants, hydrocarbons

Procedia PDF Downloads 251

Authors: N. Singh, G. K. Darbha

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Since the last decade, a wave of research has begun to study the prevalence and impact of ever-increasing plastic pollution in the environment. The wide application and ubiquitous distribution of plastic have become a global concern due to its persistent nature. The disposal of plastics has emerged as one of the major challenges for waste management landfills. Microplastics (MPs) have found its existence in almost every environment, from the high altitude mountain lake to the deep sea sediments, polar icebergs, coral reefs, estuaries, beaches, and river, etc. Microplastics are fragments of plastics with size less than 5 mm. Microplastics can be classified as primary microplastics and secondary microplastics. Primary microplastics includes purposefully introduced microplastics into the end products for consumers (microbeads used in facial cleansers, personal care product, etc.), pellets (used in manufacturing industries) or fibres (from textile industries) which finally enters into the environment. Secondary microplastics are formed by disintegration of larger fragments under the exposure of sunlight, mechanical abrasive forces by rain, waves, wind and/or water. A number of factors affect the quantity of microplastic present in freshwater environments. In addition to physical forces, human population density proximal to the water body, proximity to urban centres, water residence time, and size of the water body also affects plastic properties. With time, other complex processes in nature such as physical, chemical and biological break down plastics by interfering with its structural integrity. Several studies demonstrate that microplastics found in wastewater sludge being used as manure for agricultural fields, thus having the tendency to alter the soil environment condition influencing the microbial population as well. Inadequate data are available on the fate and transport of microplastics under varying environmental conditions that are required to supplement important information for further research. In addition, microplastics have the tendency to absorb heavy metals and hydrophobic organic contaminants such as PAHs and PCBs from its surroundings and thus acting as carriers for these contaminants in the environment system. In this study, three kinds of microplastics (polyethylene, polypropylene and expanded polystyrene) of different densities were chosen. Plastic samples were placed in sand with different aqueous media (distilled water, surface water, groundwater and marine water). It was incubated at varying temperatures (25, 35 and 40 °C) and agitation levels (rpm). The results show that the number of plastic fragments enhanced with increase in temperature and agitation speed. Moreover, the rate of disintegration of expanded polystyrene is high compared to other plastics. These results demonstrate that temperature, salinity, and mechanical abrasion plays a major role in degradation of plastics. Since weathered microplastics are more harmful as compared to the virgin microplastics, long-term studies involving other environmental factors are needed to have a better understanding of degradation of plastics.

Keywords: environmental contamination, fragmentation, microplastics, temperature, weathering

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Authors: Jan F. Talts, Amit Saxena, Kåre Engkilde

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Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most frequent side effects caused by anti-neoplastic agents, with a prevalence from 19 % to 85 %. Clinically, CIPN is a mostly sensory neuropathy leading to pain and to motor and autonomic changes. Due to its high prevalence among cancer patients, CIPN constitutes a major problem for both cancer patients and survivors, especially because currently, there is no single effective method of preventing CIPN. Hearing loss is the most common form of sensory impairment in humans and can be caused by ototoxic chemical compounds such as chemotherapy (platinum-based antineoplastic agents).In rodents, single or repeated cisplatin injections induce peripheral neuropathy and hearing impairment mimicking human disorder, allowing studying the efficacy of new pharmacological candidates in chemotherapy-induced hearing loss and peripheral neuropathy. RNA sequencing data from full term amniotic fluid (TAF) mesenchymal stemcell (MSC) clones was used to identify neural-specific markers present on TAF-MSC. Several prospective neural markers were tested by flow cytometry on cultured TAF-MSC. One of these markers was used for cell-sorting using Tyto MACSQuant cell sorter, and the neural marker positive cell population was expanded for several passages to the final therapeutic product stage. Peripheral neuropathy and hearing loss was induced in mice by administration of cisplatin in three week-long cycles. The efficacy of neural-specific TAF-MSC in treating hearing loss and pain perception was evaluated by administration of three injections of 3 million cells/kg by intravenous route or three injections of 3 million cells/kg by intra-arterial route after each cisplatin cycle treatment. Auditory brainstem responses (ABR) are electric potentials recorded from scalp electrodes, and the first ABR wave represents the summed activity of the auditory nerve fibers contacting the inner hair cells. For ABR studies, mice were anesthetized, then earphones were placed in the left ear of each mouse, an active electrode was placed in the vertex of the skull, a reference electrode under the skin of the mastoid bone, and a ground electrode in the neck skin. The stimuli consisted of tone pips of five frequencies (2, 4, 6, 12, 16, and 24 kHz) at various sound levels (from 0 to 90 dB) ranging to cover the mouse auditory frequency range. The von Frey test was used to assess the onset and maintenance of mechanical allodynia over time. Mice were placed in clear plexiglass cages on an elevated mesh floor and tested after 30 min of habituation. Mechanical paw withdrawal threshold was examined using an electronic von Frey anesthesiometer. Cisplatin groups treated with three injections of 3 million cells/kg by intravenous route and three injections of 3 million cells/kg by intra-arterial route after each cisplatin cycle treatment presented, a significant increase of hearing acuity characterized by a decrease of ABR threshold and a decrease of neuropathic pain characterized by an increase of von Frey paw withdrawal threshold compared to controls only receiving cisplatin. This study shows that treatment with MSCselected for neural specificity presents significant positive efficacy on the chemotherapy-induced neuropathic pain and the chemotherapy-induced hearing loss.

Keywords: mesenchymal stem cell, peripheral neuropathy, amniotic fluid, regenerative medicine

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Authors: Lauren Beth Birney

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BOP-CCERS is a consortium of scientists, K-16 New York City students, faculty, academicians, teachers, stakeholders, STEM Industry professionals, CBO’s, NPO’s, citizen scientists, and local businesses working in partnership to restore New York Harbor’s oyster populations while at the same time providing clean water in New York Harbor. BOP-CCERS gives students an opportunity to learn hands-on about environmental stewardship as well as environmental law and policy by giving students real responsibility. The purpose of this REU will allow for the BOP CCERS Project to further broaden its parameters into the focus of environmental law and policy where further change can be affected. Creating opportunities for undergraduates to work collaboratively with graduate students in law and policy and envision themselves in STEM careers in the field of law continues to be of importance in this project. More importantly, creating opportunities for underrepresented students to pursue careers in STEM Education has been a goal of the project over the last ten years. By raising the level of student interest in community-based citizen science integrated into environmental law and policy, a more diversified workforce will be fostered through the momentum of this dynamic program. The continuing climate crisis facing our planet calls for 21st-century skill development that includes learning and innovation skills derived from critical thinking, which will help REU students address the issues of climate change facing our planet. The demand for a climate-friendly workforce will continue to be met through this community-based citizen science effort. Environmental laws and policies play a crucial role in protecting humans, animals, resources, and habitats. Without these laws, there would be no regulations concerning pollution or contamination of our waterways. Environmental law serves as a mechanism to protect the land, air, water, and soil of our planet. To protect the environment, it is crucial that future policymakers and legal experts both understand and value the importance of environmental protection. The Environmental Law and Policy REU provides students with the opportunity to learn, through hands-on work, the skills, and knowledge needed to help foster a legal workforce centered around environmental protection while participating alongside the BOP CCERS researchers in order to gain research experience. Broadening this area to law and policy will further increase these opportunities and permit students to ultimately affect and influence larger-scale change on a global level while further diversifying the STEM workforce. Students’ findings will be shared at the annual STEM Institute at Pace University in August 2022. Basic research methodologies include qualitative and quantitative analysis performed by the research team. Early findings indicate that providing students with an opportunity to experience, explore and participate in environmental science programs such as these enhances their interests in pursuing STEM careers in Law and Policy, with the focus being on providing opportunities for underserved, marginalized, and underrepresented populations.

Keywords: environmental restoration science, citizen science, environmental law and policy, STEM education

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Authors: Till Fehlauer, Blanche Collin, Bernard Angeletti, Andrea Somogyi, Claire Lallemand, Perrine Chaurand, Cédric Dentant, Clement Levard, Jerome Rose

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Over the last decades, yttrium (Y) has gained importance in high-tech applications. It is an essential part of alloys and compounds used for lasers, displays, or cell phones, for example. Due to its chemical similarities with the lanthanides, Y is often considered a rare earth element (REE). Despite their increased usage, the environmental behavior of REEs remains poorly understood. Especially regarding their interactions with plants, many uncertainties exist. On the one hand, Y is known to have a negative effect on root development and germination, but on the other hand, it appears to promote plant growth at low concentrations. In order to understand these phenomena, a precise knowledge is necessary about how Y is absorbed by the plant and how it is handled once inside the organism. Contradictory studies exist, stating that due to a similar ionic radius, Y and the other REEs might be absorbed through Ca²⁺-channels, while others suspect that Y has a shared pathway with Al³⁺. In this study, laser ablation coupled ICP-MS, and synchrotron-based micro-X-ray fluorescence (µXRF, beamline Nanoscopium, SOLEIL, France) have been used in order to localize Y within the plant tissue and identify associated elements. The plant used in this study is Saxifraga paniculata, a rugged alpine plant that has shown an affinity for Y in previous studies (in prep.). Furthermore, Saxifraga paniculata performs guttation, which means that it possesses phloem sap secreting openings on the leaf surface that serve to regulate root pressure. These so-called hydathodes could provide special insights in elemental transport in plants. The plants have been grown on Y doped soil (500mg/kg DW) for four months. The results showed that Y was mainly concentrated in the roots of Saxifraga paniculata (260 ± 85mg/kg), and only a small amount was translocated to the leaves (10 ± 7.8mg/kg). µXRF analysis indicated that within the root transects, the majority of Y remained in the epidermis and hardly penetrated the stele. Laser ablation coupled ICP-MS confirmed this finding and showed a positive correlation in the roots between Y, Fe, Al, and to a lesser extent Ca. In the stem transect, Y was mainly detected in a hotspot of approximately 40µm in diameter situated in the endodermis area. Within the stem and especially in the hotspot, Y was highly colocalized with Al and Fe. Similar-sized Y hotspots have been detected in/on the leaves. All of them were strongly colocalized with Al and Fe, except for those situated within the hydathodes, which showed no colocalization with any of the measured elements. Accordingly, a relation between Y and Ca during root uptake remains possible, whereas a correlation to Fe and Al appears to be dominant in the aerial parts, suggesting common storage compartments, the formation of complexes, or a shared pathway during translocation.

Keywords: laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), Phytoaccumulation, Rare earth elements, Saxifraga paniculata, Synchrotron-based micro-X-ray fluorescence, Yttrium

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Authors: S. H. Chew, Z. X. Eng, K. E. Chuah, T. Y. Lim, H. M. A. Yim

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In recent years, geotextile tube has been widely used in the hydraulic engineering and dewatering industry. To construct a stable containment bund with geotextile tubes, the sand slurry is always the preference infilling material. However, the shortage of sand supply posts a problem in Singapore to adopt this construction method in the actual construction of long containment bund. Hence, utilizing the soft dredged clay or the excavated soft clay as the infilling material of geotextile tubes has a great economic benefit. There are any technical issues with using this soft clayey material as infilling material, especially on the excessive settlement and stability concerns. To minimize the shape deformation and settlement of geotextile tube associated with the use of this soft clay infilling material, a modified innovative infilling material is proposed – lightly cemented soft clay. The preliminary laboratory studies have shown that the dewatering mechanism via geotextile material of the tube skin, and the introduction of cementitious chemical action of the lightly cemented soft clay will accelerate the consolidation and improve the shear strength of infill material. This study aims to extend the study by conducting a pilot test of the geotextile tube filled with lightly cemented clay. This study consists of testing on a series of miniature geo-tubes and two full-size geotextile tube. In the miniature geo-tube tests, a number of small scaled-down size of geotextile tubes were filled with cemented clay (at water content of 150%) with cement content of 0% to 8% (by weight). The shear strength development of the lightly cemented clay under dewatering mechanism was evaluated using a modified in-situ Cone Penetration Test (CPT) at 0 days, 3 days, 7 days and 28 days after the infilling. The undisturbed soil samples of lightly cemented infilled clay were also extracted at 3-days and 7-days for triaxial tests and evaluation of final water content. The results suggested that the geotextile tubes filled with un-cemented soft clay experienced very significant shape change over the days (as control test). However, geotextile mini-tubes filled with lightly cemented clay experienced only marginal shape changed, even that the strength development of this lightly cemented clay inside the tube may not show significant strength gain at the early stage. The shape stability is believed to be due to the confinement effect of the geotextile tube with clay at non-slurry state. Subsequently, a full-scale instrumented geotextile tube filled with lightly cemented clay was performed. The extensive results of strain gauges and pressure transducers installed on this full-size geotextile tube demonstrated a substantial mobilization of tensile forces on the geotextile skin corresponding to the filling activity and the subsequent dewatering stage. Shape change and the in-fill material strength development was also monitored. In summary, the construction of containment bund with geotextile tube filled with lightly cemented clay is found to be technically feasible and stable with the use of the sufficiently strong (i.e. adequate tensile strength) geotextile tube, the adequate control on the dosage of cement content, and suitable water content of infilling soft clay material.

Keywords: cemented clay, containment bund, dewatering, geotextile tube

Procedia PDF Downloads 248

Authors: Elsie M. Nolte, Annie M. Joubert, Roy Lakier, Maryke Etsebeth, Jolene M. Helena, Marcel Verwey, Laurence Lafanechere, Anne E. Theron

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Treatment regimens for breast- and lung cancers may include both radiation- and chemotherapy. Ideally, a pharmaceutical agent which selectively sensitizes cancer cells to gamma (γ)-radiation would allow administration of lower doses of each modality, yielding synergistic anti-cancer benefits and lower metastasis occurrence, in addition to decreasing the side-effect profiles. A range of 2-methoxyestradiol (2-ME) analogues, namely 2-ethyl-3-O-sulphamoyl-estra-1,3,5 (10) 15-tetraene-3-ol-17one (ESE-15-one), 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16) were in silico-designed by our laboratory, with the aim of improving the parent compound’s bioavailability in vivo. The main effect of these compounds is the disruption of microtubule dynamics with a resultant mitotic accumulation and induction of programmed cell death in various cancer cell lines. This in vitro study aimed to determine the cellular responses involved in the radiation sensitization effects of these analogues at low doses in breast- and lung cancer cell lines. The oestrogen receptor positive MCF-7-, oestrogen receptor negative MDA-MB-231- and triple negative BT-20 breast cancer cell lines as well as the A549 lung cancer cell line were used. The minimal compound- and radiation doses able to induce apoptosis were determined using annexin-V and cell cycle progression markers. These doses (cell line dependent) were used to pre-sensitize the cancer cells 24 hours prior to 6 gray (Gy) radiation. Experiments were conducted on samples exposed to the individual- as well as the combination treatment conditions in order to determine whether the combination treatment yielded an additive cell death response. Morphological studies included light-, fluorescence- and transmission electron microscopy. Apoptosis induction was determined by flow cytometry employing annexin V, cell cycle analysis, B-cell lymphoma 2 (Bcl-2) signalling, as well as reactive oxygen species (ROS) production. Clonogenic studies were performed by allowing colony formation for 10 days post radiation. Deoxyribonucleic acid (DNA) damage was quantified via γ-H2AX foci and micronuclei quantification. Amplification of the p53 signalling pathway was determined by western blot. Results indicated that exposing breast- and lung cancer cells to nanomolar concentrations of these analogues 24 hours prior to γ-radiation induced more cell death than the compound- and radiation treatments alone. Hypercondensed chromatin, decreased cell density, a damaged cytoskeleton and an increase in apoptotic body formation were observed in cells exposed to the combination treatment condition. An increased number of cells present in the sub-G1 phase as well as increased annexin-V staining, elevation of ROS formation and decreased Bcl-2 signalling confirmed the additive effect of the combination treatment. In addition, colony formation decreased significantly. p53 signalling pathways were significantly amplified in cells exposed to the analogues 24 hours prior to radiation, as was the amount of DNA damage. In conclusion, our results indicated that pre-treatment of breast- and lung cancer cells with low doses of 2-ME analogues sensitized breast- and lung cancer cells to γ-radiation and induced apoptosis more so than the individual treatments alone. Future studies will focus on the effect of the combination treatment on non-malignant cellular counterparts.

Keywords: cancer, microtubule dynamics, radiation therapy, radiosensitization

Procedia PDF Downloads 181

Authors: Jia H. Wong, Jingli Zhang, Habsah Mohamad, Iswatun H. Abdullah Ripain, Muhammad Bilal, Amelia J. Lloyd, Abdul A. Mohamed Yusoff, Jafri M. Abdullah

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Epilepsy is one of the most common neurological diseases affecting more than 50 million of people worldwide. Epilepsy is a state of recurrent, spontaneous seizures with multiple syndromes and symptoms of different causes of brain dysfunction, prognosis, and treatments; characterized by transient, occasional and stereotyped interruptions of behavior whereby the excitatory-inhibitory activities within the central nervous system (CNS) are thrown out of balance due to various kinds of interferences. The goal of antiepileptic treatment is to enable patients to be free from seizures or to achieve control of seizures through surgical treatment and/or pharmacotherapy. Pharmacotherapy through AED plays an important role especially in countries with epilepsy treatment gap due to costs and availability of health facilities, skills and resources, yet there are about one-third of the people with epilepsy have drug-resistant seizures. Hence, this poses considerable challenges to the healthcare system and the effort in providing cost-effective treatment as well as the search for alternatives to treatment and management of epilepsy. Enhancement of γ-aminobutyric acid (GABA)-mediated inhibitory neurotransmission is one of the key mechanisms of actions of antiepileptic drugs. GABA type > a receptors (GABAAR) are ligand-gated ion channels that mediate rapid inhibitory neurotransmission upon the binding of GABA with a heteropentameric structure forming a central pore that is permeable to the influx of chloride ions in its activated state. The major isoform of GABAA receptors consists of two α1, two β2, and one γ2 subunit. It is the most abundantly expressed combinations in the brain and the most commonly researched through Xenopus laevis oocytes. With the advancing studies on ethnomedicine and traditional treatments using medicinal plants, increasing evidence reveal that spice and herb plants with medicinal properties play an important role in the treatment of ailments within communities across different cultures. Capsaicin is the primary natural capsaicinoid in hot peppers of plant genus Capsicum, consist of an aromatic ring, an amide linkage and a hydrophobic side chain. The study showed that capsaicins conferred neuroprotection in status epilepticus mouse models through anti-ictogenic, hypothermic, antioxidative, anti-inflammatory, and anti-apoptotic actions in a dose-dependent manner. In this study, five capsaicin derivatives were tested for their ability to increase the GABA-induced chloride current on α1β2γ2S of GABAAR expressed on Xenopus laevis oocytes using the method of two-microelectrode voltage clamp. Two of the capsaicin derivatives, IS5 (N-(4-hydroxy-3-methoxybenzyl)-3-methylbutyramide) and IS10 (N-(4-hydroxy-3-methoxybenzyl)-decanamide) at a concentration of 30µM were able to significantly increase the GABA-induced chloride current with p=0.002 and p=0.026 respectively. This study were able to show the enhancement effect of two capsaicin derivatives with moderate length of hydrocarbon chain on this receptor subtype, revealing the promising inhibitory activity of capsaicin derivatives through enhancement of GABA-induced chloride current and further investigations should be carried out to verify its antiepileptic effects in animal models.

Keywords: α1β2γ2 GABAA receptors, α1β2γ2S, antiepileptic, capsaicin derivatives, two-microelectrode voltage clamp, Xenopus laevis oocytes

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