Search results for: african medicinal plants
Commenced in January 2007
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Edition: International
Paper Count: 4054

Search results for: african medicinal plants

514 Infestation of Aphid on Wheat Triticum aestivum L. (Poaceae) and Its Possible Management with Naturally Existing Beneficial Fauna

Authors: Ghulam Abbas, Ikramul Haq, Ghulam Ghouse

Abstract:

Bread wheat Triticum aestivum L. (Poaceae) is the major source of the staple food for a number of countries of the world including Pakistan. Since it is the staple food of the country, it has been desired, and efforts have been made, that it does not undergo application of pesticides to ensure the food safety. Luckily, wheat does not face a serious threat of insect pests, in ecological conditions of Pakistan, except aphids and armyworm which infest the wheat prior to maturity. It has been observed that almost 5 species of aphid have been reported to attack wheat ie. Ropalosiphum maidi, R. Padi, Schizaphis graminum, Diuraphis noxia, and Sitibion miscanthi but due to natural rise in temperature in terminal season of wheat, the population of aphid gradually decreases and wheat has a safe escape from its infestation. In case, mild temperatures 15ºC to 30ºC prolong, the infestation of aphids also prolongs and it can severely damage wheat in patches, and it has potential to substantially reduce the yield of wheat in infested patch. In years 2013, 2014, and 2015 the studies were undertaken to determine the potential of damage caused by aphid complex in 10 fields in infested patches. The damage caused by aphid complex was calculated on the basis of 1000 grain weight of wheat grains taken from the infested patch and were compared with 1000 grain weight of the healthy plants of the same fields. It was observed that there was 26 to 42% decrease in the weight of grain in infested patches. This patch also escaped from general harvesting by combine harvester and enhanced the loss 13 to 46%. The quality of the wheat straw was also reduced and its acceptance to the animals was also affected up to 50 to 100%. Moreover, the population of naturally existing beneficial fauna was recorded and factors promoting establishment and manipulation of beneficial fauna were studied and analysed.

Keywords: Triticum aestivum, wheat, Pakistan, beneficial fauna, aphid complex

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513 Modelling and Simulation of Natural Gas-Fired Power Plant Integrated to a CO2 Capture Plant

Authors: Ebuwa Osagie, Chet Biliyok, Yeung Hoi

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Regeneration energy requirement and ways to reduce it is the main aim of most CO2 capture researches currently being performed and thus, post-combustion carbon capture (PCC) option is identified to be the most suitable for the natural gas-fired power plants. From current research and development (R&D) activities worldwide, two main areas are being examined in order to reduce the regeneration energy requirement of amine-based PCC, namely: (a) development of new solvents with better overall performance than 30wt% monoethanolamine (MEA) aqueous solution, which is considered as the base-line solvent for solvent-based PCC, (b) Integration of the PCC Plant to the power plant. In scaling-up a PCC pilot plant to the size required for a commercial-scale natural gas-fired power plant, process modelling and simulation is very essential. In this work, an integrated process made up of a 482MWe natural gas-fired power plant, an MEA-based PCC plant which is developed and validated has been modelled and simulated. The PCC plant has four absorber columns and a single stripper column, the modelling and simulation was performed with Aspen Plus® V8.4. The gas turbine, the heat recovery steam generator and the steam cycle were modelled based on a 2010 US DOE report, while the MEA-based PCC plant was modelled as a rate-based process. The scaling of the amine plant was performed using a rate based calculation in preference to the equilibrium based approach for 90% CO2 capture. The power plant was integrated to the PCC plant in three ways: (i) flue gas stream from the power plant which is divided equally into four stream and each stream is fed into one of the four absorbers in the PCC plant. (ii) Steam draw-off from the IP/LP cross-over pipe in the steam cycle of the power plant used to regenerate solvent in the reboiler. (iii) Condensate returns from the reboiler to the power plant. The integration of a PCC plant to the NGCC plant resulted in a reduction of the power plant output by 73.56 MWe and the net efficiency of the integrated system is reduced by 7.3 % point efficiency. A secondary aim of this study is the parametric studies which have been performed to assess the impacts of natural gas on the overall performance of the integrated process and this is achieved through investigation of the capture efficiencies.

Keywords: natural gas-fired, power plant, MEA, CO2 capture, modelling, simulation

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512 Examining Historically Defined Periods in Autobiographical Memories for Transitional Events

Authors: Khadeeja Munawar, Shamsul Haque

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We examined the plausibility of transition theory suggesting that memories of transitional events, which give rise to a significant and persistent change in the fabric of daily life, are organized around the historically defined autobiographical periods (H-DAPs). 141 Pakistani older adults retrieved 10 autobiographical memories (AMs) each to 10 cue words. As the history of Pakistan is dominated by various political and nationwide transitional events, it was expected that the participants would recall memories with H-DAPs references. The content analysis revealed that 0.7% of memories had H-DAP references and 0.4% memories mentioned major transitional events such as War/Natural Disaster. There was a vivid reminiscence bump between 10 - 20 years of age in lifespan distribution of AMs. There were 67.9% social-focused AMs. Significantly more self-focused memories were reported by individuals who endorsed themselves as conservatives. Only a few H-DAPs were reported, although the history of Pakistan was dominated by numerous political, historical and nationwide transitional events. Memories within and outside of the bump period were mostly positive. The participants rarely used historical/political or nationwide significant events or periods to date the memories elicited. The intense and nationwide (as well as region-wise) significant historical/political events spawned across decades in the lives of participants of the present study but these events did not produce H-DAPs. The findings contradicted the previous studies on H-DAPs and transition theory. The dominance of social-focused AMs in the present study is in line with the past studies comparing the memories of collectivist and individualist cultures (i.e., European Americans vs. Asian, African and Latin-American cultures). The past empirical evidence shows that conservative values and beliefs are adopted as a coping strategy to feel secure in the face of danger when future is dominated with uncertainty and to connect to likeminded others. In the present study, conservative political ideology is somehow assisting the participants in living a stable life midst of their complex social worlds. The reminiscence bump, as well as dominance of positive memories within and outside the bump period, are in line with the narrative/identity account which states that the events and experiences during adolescence and early adulthood assimilate into a person’s lifelong narratives. Hence these events are used as identity markers and are more easily recalled later in life. Also, according to socioemotional theory and the positivity effect, the participants evaluated past events more positively as they grow up and the intensity of negative emotions decreased with time.

Keywords: autobiographical memory, historically defined autobiographical periods, narrative/identity account, Pakistan, reminiscence bump, SMS framework, transition theory

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511 Analogy in Microclimatic Parameters, Chemometric and Phytonutrient Profiles of Cultivated and Wild Ecotypes of Origanum vulgare L., across Kashmir Himalaya

Authors: Sumira Jan, Javid Iqbal Mir, Desh Beer Singh, Anil Sharma, Shafia Zaffar Faktoo

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Background and Aims: Climatic and edaphic factors immensely influence crop quality and proper development. Regardless of economic potential, Himalayan Oregano has not subjected to phytonutrient and chemometric evaluation and its relationship with environmental conditions are scarce. The central objective of this research was to investigate microclimatic variation among wild and cultivated populations located in a microclimatic gradient in north-western Himalaya, Kashmir and analyse if such disparity was related with diverse climatic and edaphic conditions. Methods: Micrometeorological, Atomic absorption spectroscopy for micro elemental analysis was carried for soil. HPLC was carried out to estimate variation in phytonutrients and phytochemicals. Results: Geographic variation in phytonutrient was observed among cultivated and wild populations and among populations diverse within regions. Cultivated populations exhibited comparatively lesser phytonutrient value than wild populations. Moreover, our results observed higher vegetative growth of O. vulgare L. with higher pH (6-7), elevated organic carbon (2.42%), high nitrogen (97.41Kg/ha) and manganese (10-12ppm) and zinc contents (0.39-0.50) produce higher phytonutrients. HPLC data of phytonutrients like quercetin, betacarotene, ascorbic acid, arbutin and catechin revealed direct relationship with UV-B flux (r2=0.82), potassium (r2=0.97) displaying parallel relationship with phytonutrient value. Conclusions: Catechin was found as predominant phytonutrient among all populations with maximum accumulation of 163.8 ppm while as quercetin exhibited lesser value. Maximum arbutin (53.42ppm) and quercetin (2.87ppm) accumulated in plants thriving under intense and high UV-B flux. Minimum variation was demonstrated by beta carotene and ascorbic acid.

Keywords: phytonutrient, ascorbic acid, beta carotene, quercetin, catechin

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510 The Effects of Inoculation and N Fertilization on Soybean (Glycine max (L.) Merr.) Seed Yield and Protein Concentration under Drought Stress

Authors: Oqba Basal, Andras Szabo

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Using mineral fertilization is increasing worldwide, as it is claimed to be majorly responsible for achieving high yields; however, the negative impacts of mineral fertilization on soil and environment are becoming more obvious, with alternative methods being more necessary and applicable, especially with the current climatic changes which have imposed serious abiotic stresses, such as drought. An experiment was made during 2017 growing season in Debrecen, Hungary to investigate the effects of inoculation and N fertilization on the seed yield and protein concentration of the soybean (Glycine max (L.) Merr.) cultivar (Panonia Kincse) under three different irrigation regimes: severe drought stress (SD), moderate drought stress (MD) and control with no drought stress (ND). Three N fertilizer rates were applied: no N fertilizer (0 N), 35 kg ha⁻¹ of N fertilizer (35 N) and 105 kg ha⁻¹ of N fertilizer (105 N). Half of the seeds in each treatment was inoculated with Bradyrhizobium japonicum inoculant, and the other half was not inoculated. The results showed significant differences in the seed yield associated with inoculation, irrigation and the interaction between them, whereas there were no significant differences in the seed yield associated with fertilization alone or in interaction with inoculation or irrigation or both. When seeds were inoculated, yield was increased when (35 N) was applied compared to (0 N) but not significantly; however, the high rate of N fertilizer (105 N) reduced the yield to a level even less than (0 N). When seeds were not inoculated, the highest rate of N increased the yield the most compared to the other two N fertilizer rates whenever the drought was present (moderate or severe). Under severe drought stress, inoculation was positively and significantly correlated with yield; however, adding N fertilizer increased the yield of uninoculated plants compared to the inoculated ones, regardless of the rate of N fertilizer. Protein concentration in the seeds was significantly affected by irrigation and by fertilization, but not by inoculation. Protein concentration increased as the N fertilization rate increased, regardless of the inoculation or irrigation treatments; moreover, increasing the N rate reduced the correlation coefficient of protein concentration with the irrigation. It was concluded that adding N fertilizer is not always recommended, especially when seeds are inoculated before being sown; however, it is very important under severe drought stress to sustain yield. Enhanced protein concentrations could be achieved by applying N fertilization, whether the seeds were pre-inoculated or not.

Keywords: drought stress, N fertilization, protein concentration, soybean

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509 Bacteriophage Lysis Of Physiologically Stressed Listeria Monocytogenes In A Simulated Seafood Processing Environment

Authors: Geevika J. Ganegama Arachchi, Steve H. Flint, Lynn McIntyre, Cristina D. Cruz, Beatrice M. Dias-Wanigasekera, Craig Billington, J. Andrew Hudson, Anthony N. Mutukumira

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In seafood processing plants, Listeriamonocytogenes(L. monocytogenes)likely exists in a metabolically stressed state due to the nutrient-deficient environment, processing treatments such as heating, curing, drying, and freezing, and exposure to detergents and disinfectants. Stressed L. monocytogenes cells have been shown to be as pathogenic as unstressed cells. This study investigated lytic efficacy of (LiMN4L, LiMN4p, and LiMN17) which were previouslycharacterized as virulent against physiologically stressed cells of three seafood borne L. monocytogenesstrains (19CO9, 19DO3, and 19EO3).Physiologically compromised cells ofL. monocytogenesstrains were prepared by aging cultures in TrypticaseSoy Broth at 15±1°C for 72 h; heat injuringcultures at 54±1 - 55±1°C for 40 - 60 min;salt-stressing cultures in Milli-Q water were incubated at 25±1°C in darkness for three weeks; and incubating cultures in 9% (w/v) NaCl at 15±1°C for 72 h. Low concentrations of physiologically compromised cells of three L. monocytogenesstrainswere challenged in vitrowith high titre of three phages in separate experiments using Fish Broth medium (aqueous fish extract) at 15 °C in order to mimic the environment of seafood processing plant. Each phage, when present at ≈9 log10 PFU/ml, reduced late exponential phase cells of L. monocytogenes suspended in fish protein broth at ≈2-3 log10 CFU/ml to a non-detectable level (< 10 CFU/ml). Each phage, when present at ≈8.5 log10 PFU/ml, reduced both heat-injured cells present at 2.5-3.6 log10 CFU/ml and starved cells that were showed coccoid shape, present at ≈2-3 log10 CFU/ml to < 10 CFU/ml after 30 min. Phages also reduced salt-stressed cellspresent at ≈3 log10 CFU/ml by > 2 log10. L. monocytogenes (≈8 log10 CFU/ml) were reduced to below the detection limit (1 CFU/ml) by the three successive phage infections over 16 h, indicating that emergence of spontaneous phage resistance was infrequent. The three virulent phages showed high decontamination potential for physiologically stressed L. monocytogenes strains from seafood processing environments.

Keywords: physiologically stressed L. monocytogenes, heat injured, seafood processing environment, virulent phage

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508 Youth Participation in Peace Building and Development in Northern Uganda

Authors: Eric Awich Ochen

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The end of the conflict in Northern Uganda in 2006 brought about an opportunity for the youth to return to their original home and contribute to the peace building and development process of their communities. Post-conflict is used here to refer to the post-armed conflict situation and activities of rebels of Joseph Kony in northern Uganda. While the rebels remain very much active in the Sudan and Central African Republic, in Uganda the last confrontations occurred around 2006 or earlier, and communities have returned to their homes and began the process of rebuilding their lives. It is argued that socio-economic reconstruction is at the heart of peacebuilding and sustenance of positive peace in the aftermath of conflict, as it has a bearing on post-conflict stability and good governance. We recognize that several post-conflict interventions within Northern Uganda have targeted women and children with a strong emphasis on family socio-economic empowerment and capacity building, including access to micro finance. The aim of this study was to examine the participation of the youth in post-conflict peace building and development in Northern Uganda by assessing the breadth and width of their engagement and the stages of programming cycle that they are involved in, interrogating the space for participation and how they are facilitating or constraining participation. It was further aimed at examining the various dimensions of participation at play in Northern Uganda and where this fits within the conceptual debates on peace building and development in the region. Supporting young people emerging out of protracted conflict to re-establish meaningful socio-economic engagements and livelihoods is fundamental to their participation in the affairs of the community. The study suggests that in the post-conflict development context of Northern Uganda, participation has rarely been disaggregated or differentiated by sectors or groups. Where some disaggregation occurs, then the main emphasis has always been on either women or children. It appears therefore that little meaningful space has thus been created for young people to engage and participate in peace building initiatives within the region. In other cases where some space is created for youth participation, this has been in pre-conceived programs or interventions conceived by the development organizations with the youth or young people only invited to participate at particular stages of the project implementation cycle. Still within the implementation of the intervention, the extent to which young people participate is bounded, with little power to influence the course of the interventions or make major decisions. It is thus visible that even here young people mainly validate and legitimize what are predetermined processes only act as pawns in the major chess games played by development actors (dominant peace building partners). This paper, therefore, concludes that the engagement of the youth in post-conflict peace building has been quite problematic and tokenistic and has not given the adequate youth space within which they could ably participate and express themselves in the ensuing interventions.

Keywords: youth, conflict, peace building, participation

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507 Cilubaba: An Agriculture-Based Education Tool through Congklak Traditional Game as an Introduction of Home Garden for Children in Cibanteng, Bogor

Authors: Yoni Elviandri, Vivi Fitriyanti, Agung Surya Wijaya, Suryani Humayyah, Muhammad Alif Azizi

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The massive development of computing power and internet access nowadays is marked by audiovisual games and computers which are known as electronic games, one of the examples is online games. This kind of game can be found everywhere in Indonesia, both in the cities and even the villages. In the present time, online games are becoming a popular games in various layers of the community, one of them does happen to elementary school students. As the online games spread over, the traditional games gradually fade away and even thought as an old-fashioned game. Contrary, traditional games actually have the better and higher educational values such as patience, honesty, integrity and togetherness value which cannot be found in online games which are more to individualist. A brand new set of education tools is necessary to provide a convenience, safe and fun place for children to play around but still contains educational values. One interesting example goes to Cilulaba is an agricultural-based playground. It is a good place for children to play and learn as it was planned to entertain children to play around as well as introducing agriculture to them. One of the games is a 1990’s well-known traditional game which its name is Congklak. Congklak is an agricultural-based traditional game and it also introduces the home garden to the children. Some of the Cilulaba’s aims are to protect the existence of nation’s cultural inheritance through Congklak traditional game, as a tool to introduce the agriculture to the children through the methods of Congklak traditional game and giving explanation related to the advantages of a “healthy home garden” to the children. The expected output from this place is to deliver a good understanding about agriculture to the children and make them begin to love it to make an aesthetic home garden and enhance the optimalisation usage of home garden that will support the availability of various edible plants in productive and health households. The proposed method in this Student Creative Program in Society Service is Participatory Rural Appraisal (PRA) method.

Keywords: Cilubaba, Congklak, traditional game, agricultural-based playground

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506 Changes in Forest Cover Regulate Streamflow in Central Nigerian Gallery Forests

Authors: Rahila Yilangai, Sonali Saha, Amartya Saha, Augustine Ezealor

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Gallery forests in sub-Saharan Africa are drastically disappearing due to intensive anthropogenic activities thus reducing ecosystem services, one of which is water provisioning. The role played by forest cover in regulating streamflow and water yield is not well understood, especially in West Africa. This pioneering 2-year study investigated the interrelationships between plant cover and hydrology in protected and unprotected gallery forests. Rainfall, streamflow, and evapotranspiration (ET) measurements/estimates over 2015-2016 were obtained to form a water balance for both catchments. In addition, transpiration in the protected gallery forest with high vegetation cover was calculated from stomatal conductance readings of selected species chosen from plot level data of plant diversity and abundance. Results showed that annual streamflow was significantly higher in the unprotected site than the protected site, even when normalized by catchment area. However, streamflow commenced earlier and lasted longer in the protected site than the degraded unprotected site, suggesting regulation by the greater tree density in the protected site. Streamflow correlated strongly with rainfall with the highest peak in August. As expected, transpiration measurements were less than potential evapotranspiration estimates, while rainfall exceeded ET in the water cycle. The water balance partitioning suggests that the lower vegetation cover in the unprotected catchment leads to a larger runoff in the rainy season and less infiltration, thereby leading to streams drying up earlier, than in the protected catchment. This baseline information is important in understanding the contribution of plants in water cycle regulation, for modeling integrative water management in applied research and natural resource management in sustaining water resources with changing the land cover and climate uncertainties in this data-poor region.

Keywords: evapotranspiration, gallery forest, rainfall, streamflow, transpiration

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505 Influence of the Moisture Content on the Flowability of Fine-Grained Iron Ore Concentrate

Authors: C. Lanzerstorfer, M. Hinterberger

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The iron content of the ore used is crucial for the productivity and coke consumption rate in blast furnace pig iron production. Therefore, most iron ore deposits are processed in beneficiation plants to increase the iron content and remove impurities. In several comminution stages, the particle size of the ore is reduced to ensure that the iron oxides are physically liberated from the gangue. Subsequently, physical separation processes are applied to concentrate the iron ore. The fine-grained ore concentrates produced need to be transported, stored, and processed. For smooth operation of these processes, the flow properties of the material are crucial. The flowability of powders depends on several properties of the material: grain size, grain size distribution, grain shape, and moisture content of the material. The flowability of powders can be measured using ring shear testers. In this study, the influence of the moisture content on the flowability for the Krivoy Rog magnetite iron ore concentrate was investigated. Dry iron ore concentrate was mixed with varying amounts of water to produce samples with a moisture content in the range of 0.2 to 12.2%. The flowability of the samples was investigated using a Schulze ring shear tester. At all measured values of the normal stress (1.0 kPa – 20 kPa), the flowability decreased significantly from dry ore to a moisture content of approximately 3-5%. At higher moisture contents, the flowability was nearly constant, while at the maximum moisture content the flowability improved for high values of the normal stress only. The results also showed an improving flowability with increasing consolidation stress for all moisture content levels investigated. The wall friction angle of the dust with carbon steel (S235JR), and an ultra-high molecule low-pressure polyethylene (Robalon) was also investigated. The wall friction angle increased significantly from dry ore to a moisture content of approximately 3%. For higher moisture content levels, the wall friction angles were nearly constant. Generally, the wall friction angle was approximately 4° lower at the higher wall normal stress.

Keywords: iron ore concentrate, flowability, moisture content, wall friction angle

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504 The Growth Reaction, Membrane Potential and Oxidative Stress of Maize Coleoptile Cells Incubated in the Presence of the Naphthoquinones

Authors: Malgorzata Rudnicka, Waldemar Karcz

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Introduction: Naphthoquinones are widely occurring organic compounds produced by bacteria, fungi, and plants. They can act as the functional components of biochemical systems (plastoquinone) as well as biologically active substances, which have a negative impact on environmental processes. Naphthoquinones seem to act through two mechanisms: a covalent modification of biological molecules at their nucleophilic sites or by generation of reactive oxygen species (ROS) connected with redox cycling. Investigating the effect of naphthoquinones (1,4-naphthoquinone, lawsone and naphthazarin) on the elongation growth, membrane potential and the level of oxidative stress of maize cells seems to be important due to the possibility of using these substances as herbicides. Methods: All experiments were performed on etiolated maize coleoptile segments. Simultaneous measurements of elongation growth and pH of the incubation medium were carried out using an angular position transducer, allowing a precise record of the growth kinetics. To compare the oxidative stress level induced by all tested naphthoquinones, the changes in malondialdehyde content, as well as superoxide dismutase and catalase activities were measured. In order to measure the membrane potential of parenchymal cells the standard electrophysiology technique was used. Results: Naphthoquinones such as: 1,4-naphthoquinone, lawsone and naphthazarin were studied. It was found that all of the naphthoquinones diminished the growth of the maize coleoptile cells depending on the type of naphthoquinones and their concentration. Interestingly, naphthazarin at the intermediate concentration was less toxic compared to the others. In addition, the effect of naphthoquinones on the oxidative stress was dependent on their concentration as well. Superoxide dismutase and catalase activities were changed in the presence of higher concentrations of naphthoquinones. Similar interrelations were observed for membrane potential changes. Conclusion: It can be concluded that naphthoquinones tested differ in their toxic effect on the growth of maize coleoptile cells. Furthermore, naphthoquinones can be distinguish considering the oxidative stress level and membrane potential changes. The results presented here give new insight into the possible opportunities of practical usage of naphthoquinones for herbicides improvement.

Keywords: growth rate, membrane potential, naphthoquinones, oxidative stress

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503 Influence of Ammonia Emissions on Aerosol Formation in Northern and Central Europe

Authors: A. Aulinger, A. M. Backes, J. Bieser, V. Matthias, M. Quante

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High concentrations of particles pose a threat to human health. Thus, legal maximum concentrations of PM10 and PM2.5 in ambient air have been steadily decreased over the years. In central Europe, the inorganic species ammonium sulphate and ammonium nitrate make up a large fraction of fine particles. Many studies investigate the influence of emission reductions of sulfur- and nitrogen oxides on aerosol concentration. Here, we focus on the influence of ammonia (NH3) emissions. While emissions of sulphate and nitrogen oxides are quite well known, ammonia emissions are subject to high uncertainty. This is due to the uncertainty of location, amount, time of fertilizer application in agriculture, and the storage and treatment of manure from animal husbandry. For this study, we implemented a crop growth model into the SMOKE emission model. Depending on temperature, local legislation, and crop type individual temporal profiles for fertilizer and manure application are calculated for each model grid cell. Additionally, the diffusion from soils and plants and the direct release from open and closed barns are determined. The emission data was used as input for the Community Multiscale Air Quality (CMAQ) model. Comparisons to observations from the EMEP measurement network indicate that the new ammonia emission module leads to a better agreement of model and observation (for both ammonia and ammonium). Finally, the ammonia emission model was used to create emission scenarios. This includes emissions based on future European legislation, as well as a dynamic evaluation of the influence of different agricultural sectors on particle formation. It was found that a reduction of ammonia emissions by 50% lead to a 24% reduction of total PM2.5 concentrations during winter time in the model domain. The observed reduction was mainly driven by reduced formation of ammonium nitrate. Moreover, emission reductions during winter had a larger impact than during the rest of the year.

Keywords: ammonia, ammonia abatement strategies, ctm, seasonal impact, secondary aerosol formation

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502 Significance of Treated Wasteater in Facing Consequences of Climate Change in Arid Regions

Authors: Jamal A. Radaideh, A. J. Radaideh

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Being a problem threatening the planet and its ecosystems, the climate change has been considered for a long time as a disturbing topic impacting water resources in Jordan. Jordan is expected for instance to be highly vulnerable to climate change consequences given its unbalanced distribution between water resources availability and existing demands. Thus, action on adaptation to climate impacts is urgently needed to cope with the negative consequences of climate change. Adaptation to global change must include prudent management of treated wastewater as a renewable resource, especially in regions lacking groundwater or where groundwater is already over exploited. This paper highlights the expected negative effects of climate change on the already scarce water sources and to motivate researchers and decision makers to take precautionary measures and find alternatives to keep the level of water supplies at the limits required for different consumption sectors in terms of quantity and quality. The paper will focus on assessing the potential for wastewater recycling as an adaptation measure to cope with water scarcity in Jordan and to consider wastewater as integral part of the national water budget to solve environmental problems. The paper also identified a research topic designed to help the nation progress in making the most appropriate use of the resource, namely for agricultural irrigation. Wastewater is a promising alternative to fill the shortage in water resources, especially due to climate changes, and to preserve the valuable fresh water to give priority to securing drinking water for the population from these resources and at the same time raise the efficiency of the use of available resources. Jordan has more than 36 wastewater treatment plants distributed throughout the country and producing about 386,000 CM/day of reclaimed water. According to the reports of water quality control programs, more than 85 percent of this water is of a quality that is completely identical to the quality suitable for irrigation of field crops and forest trees according to the requirements of Jordanian Standard No. 893/2006.

Keywords: climate change effects on water resources, adaptation on climate change, treated wastewater recycling, arid and semi-arid regions, Jordan

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501 The Role of Home Composting in Waste Management Cost Reduction

Authors: Nahid Hassanshahi, Ayoub Karimi-Jashni, Nasser Talebbeydokhti

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Due to the economic and environmental benefits of producing less waste, the US Environmental Protection Agency (EPA) introduces source reduction as one of the most important means to deal with the problems caused by increased landfills and pollution. Waste reduction involves all waste management methods, including source reduction, recycling, and composting, which reduce waste flow to landfills or other disposal facilities. Source reduction of waste can be studied from two perspectives: avoiding waste production, or reducing per capita waste production, and waste deviation that indicates the reduction of waste transfer to landfills. The present paper has investigated home composting as a managerial solution for reduction of waste transfer to landfills. Home composting has many benefits. The use of household waste for the production of compost will result in a much smaller amount of waste being sent to landfills, which in turn will reduce the costs of waste collection, transportation and burial. Reducing the volume of waste for disposal and using them for the production of compost and plant fertilizer might help to recycle the material in a shorter time and to use them effectively in order to preserve the environment and reduce contamination. Producing compost in a home-based manner requires very small piece of land for preparation and recycling compared with other methods. The final product of home-made compost is valuable and helps to grow crops and garden plants. It is also used for modifying the soil structure and maintaining its moisture. The food that is transferred to landfills will spoil and produce leachate after a while. It will also release methane and greenhouse gases. But, composting these materials at home is the best way to manage degradable materials, use them efficiently and reduce environmental pollution. Studies have shown that the benefits of the sale of produced compost and the reduced costs of collecting, transporting, and burying waste can well be responsive to the costs of purchasing home compost machine and the cost of related trainings. Moreover, the process of producing home compost may be profitable within 4 to 5 years and as a result, it will have a major role in reducing waste management.

Keywords: compost, home compost, reducing waste, waste management

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500 Germination and Bulb Formation of Allium tuncelianum L. under in vitro Condition

Authors: Suleyman Kizil, Tahsin Sogut, Khalid M. Khawar

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Genus Allium includes 600 to 750 species and most of these including Allium tuncelianum (Kollman) N. Ozhatay, B. Mathew & Siraneci; Syn; A. macrochaetum Boiss. and Hausskn. subsp. tuncelianum Kollman] or Tunceli garlic is endemic to Eastern Turkish Province of Tunceli and Munzur mountains. They are edible, bear attractive white-to-purple flowers and fertile black seeds with deep seed dormancy. This study aimed to break seed dormancy of Tunceli garlic and determine the conditions for induction of bulblets on these seeds and increase their diameter by culturing them on MS medium supplemented different strengths of KNO3. Tunceli garlic seeds were collected from field grown plants. They were germinated on MS medium with or without 20 g/l sucrose followed by their culture on 1 × 1900 mg/l, 2 × 1900 mg/l, 4 ×1900 mg/l and 6 × 1900 mg/l mg/l KNO3 supplemented with 20 g/l sucrose to increase bulb diameter. Improved seeds germination was noted on MS medium with and without sucrose but with variation compared to previous reports. The bulb development percentage on each of the sprouted seeds was not parallel to the percentage of seed germination. The results showed 34% and 28.5% bulb induction was noted on germinated seeds after 150 and 158 days on MS medium containing 20 g l-1 sucrose and no sucrose respectively showing a delay of 8 days on the latter compared to the former. The results emphatically noted role of cold stratification on agar solidified MS medium supplemented with sucrose to improve seed germination. The best increase in bulb diameter was noted on MS medium containing 1 × 1900 mg/l KNO3 after 178 days with bulblet diameter and bulblet weight of 0.54 cm and 0.048 g, respectively. Consequently, the bulbs induced on sucrose containing MS medium could be transferred to pots earlier. Increased (>1 × 1900 mg/l KNO3) strengths of KNO3 induced negative effect on growth and development of Tunceli garlic bulbs. The strategy of seed germination and bulblet induction reported in this study could be positively used for conservation of this endemic plant species.

Keywords: Tunceli garlic, seed, dormancy, bulblets, bulb growth

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499 Migrant Entrepreneurs and Their Spark for Entrepreneurial Exploration

Authors: Adesuwa Omorede, Karin Axelsson

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The war and violence around the world today has brought a mass increase of forcibly displaced individuals to seek refuge in the European Union, where they have to leave their homes and restart a new life built on other cultural, social, economic and legal premises than they are used to. Since 2014, the EU has accepted to help with the crisis by providing protection and refuge, and countries like Germany, Hungary, Austria, and Sweden accepted around two-thirds of EU’s asylum seekers. In 2015 for instance, Sweden harbored large numbers of refugees, which lead to a drastic rise in population. This drastic rise brought an overwhelming challenge to Sweden since they needed to find quick and suitable solutions to accommodate these thousands of refugees. Further, it posed a challenge for Sweden to immediately tackle the problem of integrating the new arrivals in the labor market. With an unstable societal integration and little or no skills to connect to the workforce, these immigrants faced a shaky beginning, as they had to struggle with not just integrating into a new society but also to get suitable jobs. These uncertainties brought pressure on the immigrants, which drove a number of them to move from city to city seeking for a place and alternatives for their well-being, safe haven, and self-provision. As a result, they brought in their own skills, experiences, and cultural orientation into exploring and exploiting new opportunities and filling the gaps in their new environment. In so doing, immigrants contributing with multidisciplinary collaborations, insights, international relations and national growth through the exploitation of entrepreneurial opportunities. The study, seek to understand how these uncertainties led migrant entrepreneurs towards entrepreneurial activities. Furthermore, it contributes to understanding their processes towards exploring and exploiting opportunities for entrepreneurship as well as their role in contributing to local and national growth. To reach these aims, an inductive qualitative study was conducted using semi-structured interviews of several migrant entrepreneurs – both female and male – that took part in two different entrepreneurial projects in mid-Sweden. The first project was a business program for African women; the other was an entrepreneurship hub for immigrants. Both were focused on inspiring and coaching immigrants during their entrepreneurial process. An integrated part was to work with the participants’ entrepreneurial skills and abilities. In addition, archival documents were collected. The data was analyzed using content analysis for qualitative research. The study aims to contribute to the entrepreneurship literature by understanding the influences of cognitive and environmental factors towards entrepreneurial activities. This study also provides several suggestions for policymakers on how they can better integrate migrants into becoming contributors to the society.

Keywords: entrepreneurial intentions, entrepreneurial processes, migrant entrepreneurship, uncertainty

Procedia PDF Downloads 194
498 Image Processing-Based Maize Disease Detection Using Mobile Application

Authors: Nathenal Thomas

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In the food chain and in many other agricultural products, corn, also known as maize, which goes by the scientific name Zea mays subsp, is a widely produced agricultural product. Corn has the highest adaptability. It comes in many different types, is employed in many different industrial processes, and is more adaptable to different agro-climatic situations. In Ethiopia, maize is among the most widely grown crop. Small-scale corn farming may be a household's only source of food in developing nations like Ethiopia. The aforementioned data demonstrates that the country's requirement for this crop is excessively high, and conversely, the crop's productivity is very low for a variety of reasons. The most damaging disease that greatly contributes to this imbalance between the crop's supply and demand is the corn disease. The failure to diagnose diseases in maize plant until they are too late is one of the most important factors influencing crop output in Ethiopia. This study will aid in the early detection of such diseases and support farmers during the cultivation process, directly affecting the amount of maize produced. The diseases in maize plants, such as northern leaf blight and cercospora leaf spot, have distinct symptoms that are visible. This study aims to detect the most frequent and degrading maize diseases using the most efficiently used subset of machine learning technology, deep learning so, called Image Processing. Deep learning uses networks that can be trained from unlabeled data without supervision (unsupervised). It is a feature that simulates the exercises the human brain goes through when digesting data. Its applications include speech recognition, language translation, object classification, and decision-making. Convolutional Neural Network (CNN) for Image Processing, also known as convent, is a deep learning class that is widely used for image classification, image detection, face recognition, and other problems. it will also use this algorithm as the state-of-the-art for my research to detect maize diseases by photographing maize leaves using a mobile phone.

Keywords: CNN, zea mays subsp, leaf blight, cercospora leaf spot

Procedia PDF Downloads 69
497 Dust Particle Removal from Air in a Self-Priming Submerged Venturi Scrubber

Authors: Manisha Bal, Remya Chinnamma Jose, B.C. Meikap

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Dust particles suspended in air are a major source of air pollution. A self-priming submerged venturi scrubber proven very effective in cases of handling nuclear power plant accidents is an efficient device to remove dust particles from the air and thus aids in pollution control. Venturi scrubbers are compact, have a simple mode of operation, no moving parts, easy to install and maintain when compared to other pollution control devices and can handle high temperatures and corrosive and flammable gases and dust particles. In the present paper, fly ash particles recognized as a high air pollutant substance emitted mostly from thermal power plants is considered as the dust particle. Its exposure through skin contact, inhalation and indigestion can lead to health risks and in severe cases can even root to lung cancer. The main focus of this study is on the removal of fly ash particles from polluted air using a self-priming venturi scrubber in submerged conditions using water as the scrubbing liquid. The venturi scrubber comprising of three sections: converging section, throat and diverging section is submerged inside a water tank. The liquid enters the throat due to the pressure difference composed of the hydrostatic pressure of the liquid and static pressure of the gas. The high velocity dust particles atomize the liquid droplets at the throat and this interaction leads to its absorption into water and thus removal of fly ash from the air. Detailed investigation on the scrubbing of fly ash has been done in this literature. Experiments were conducted at different throat gas velocities, water levels and fly ash inlet concentrations to study the fly ash removal efficiency. From the experimental results, the highest fly ash removal efficiency of 99.78% is achieved at the throat gas velocity of 58 m/s, water level of height 0.77m with fly ash inlet concentration of 0.3 x10⁻³ kg/Nm³ in the submerged condition. The effect of throat gas velocity, water level and fly ash inlet concentration on the removal efficiency has also been evaluated. Furthermore, experimental results of removal efficiency are validated with the developed empirical model.

Keywords: dust particles, fly ash, pollution control, self-priming venturi scrubber

Procedia PDF Downloads 158
496 Inhibition of Echis ocellatus Venom Metalloprotease by Flavonoid-Rich Ethyl Acetate Sub-fraction of Moringa oleifera Leaves (Lam.): in vitro and in silico Approaches

Authors: Adeyi Akindele Oluwatosin, Mustapha Kaosarat Keji, Ajisebiola Babafemi Siji, Adeyi Olubisi Esther, Damilohun Samuel Metibemu, Raphael Emuebie Okonji

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Envenoming by Echis ocellatus is potentially life-threatening due to severe hemorrhage, renal failure, and capillary leakage. These effects are attributed to snake venom metalloproteinases (SVMPs). Due to drawbacks in the use of antivenom, natural inhibitors from plants are of interest in studies of new antivenom treatment. Antagonizing effects of bioactive compounds of Moringa oleifera, a known antisnake plant, are yet to be tested against SVMPs of E. ocellatus (SVMP-EO). Ethanol crude extract of M. oleifera was partitioned using n-hexane and ethyl acetate. Each partition was fractionated using column chromatography and tested against SVMP-EO purified through ion-exchange chromatography with EchiTab-PLUS polyvalent anti-venom as control. Phytoconstituents of ethyl acetate fraction were screened against the catalytic site of crystal of BaP1-SVMP, while drug-likeness and ADMET toxicity of compound were equally determined. The molecular weight of isolated SVMP-EO was 43.28 kDa, with a specific activity of 245 U/ml, a percentage yield of 62.83 %, and a purification fold of 0.920. The Vmax and Km values are 2 mg/ml and 38.095 μmol/ml/min, respectively, while the optimal pH and temperature are 6.0 and 40°C, respectively. Polyvalent anti-venom, crude extract, and ethyl acetate fraction of M. oleifera exhibited a complete inhibitory effect against SVMP-EO activity. The inhibitions of the P-1 and P-II metalloprotease’s enzymes by the ethyl acetate fraction are largely due to methanol, 6, 8, 9-trimethyl-4-(2-phenylethyl)-3-oxabicyclo[3.3.1]non-6-en-1-yl)- and paroxypropione, respectively. Both compounds are potential drug candidates with little or no concern of toxicity, as revealed from the in-silico predictions. The inhibitory effects suggest that this compound might be a therapeutic candidate for further exploration for treatment of Ocellatus’ envenoming.

Keywords: Echis ocellatus, Moringa oleifera, anti-venom, metalloproteases, snakebite, molecular docking

Procedia PDF Downloads 140
495 Use of Zikani’s Ribosome Modulating Agents for Treating Recessive Dystrophic & Junctional Epidermolysis Bullosa with Nonsense Mutations

Authors: Mei Chen, Yingping Hou, Michelle Hao, Soheil Aghamohammadzadeh, Esteban Terzo, Roger Clark, Vijay Modur

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Background: Recessive Dystrophic Epidermolysis Bullosa (RDEB) is a genetic skin condition characterized by skin tearing and unremitting blistering upon minimal trauma. Repeated blistering, fibrosis, and scarring lead to aggressive squamous cell carcinoma later in life. RDEB is caused by mutations in the COL7A1 gene encoding collagen type VII (C7), the major component of anchoring fibrils mediating epidermis-dermis adherence. Nonsense mutations in the COL7A1 gene of a subset of RDEB patients leads to premature termination codons (PTC). Similarly, most Junctional Epidermolysis Bullosa (JEB) cases are caused by nonsense mutations in the LAMB3 gene encoding the β3 subunit of laminin 332. Currently, there is an unmet need for the treatment of RDEB and JEB. Zikani Therapeutics has discovered an array of macrocyclic compounds with ring structures similar to macrolide antibiotics that can facilitate readthrough activity of nonsense mutations in the COL7A1 and LAMB3 genes by acting as Ribosome Modulating Agents (RMAs). The medicinal chemistry synthetic advancements of these macrocyclic compounds have allowed targeting the human ribosome while preserving the structural elements responsible for the safety and pharmacokinetic profile of clinically used macrolide antibiotics. Methods: C7 expression was used as a measure of readthrough activity by immunoblot assays in two primary human fibroblasts from RDEB patients (R578X/R578X and R163X/R1683X-COL7A1). Similarly, immunoblot assays in C325X/c.629-12T > A-LAMB3 keratinocytes were used to measure readthrough activity for JEB. The relative readthrough activity of each compound was measured relative to Gentamicin. An imaging-based fibroblast migration assay was used as an assessment of C7 functionality in RDEB-fibroblasts over 16-20 hrs. The incubation period for the above experiments was 48 hrs for RDEB fibroblasts and 72 hours for JEB keratinocytes. Results: 9 RMAs demonstrated increased protein expression in both patient RDEB fibroblasts. The highest readthrough activity at tested concentrations without cytotoxicities increased protein expression up to 179% of Gentamicin (400 µg/ml), with favored readthrough activity in R163X/R1683X-COL7A1 fibroblasts. Concurrent with protein expression, fibroblast hypermotility phenotype observed in RDEB was rescued by reducing motility by ~35% to WT levels (the same level as 690 µM Gentamicin treated cells). Laminin β3 expression was also shown to be increased by 6 RMAs in keratinocytes to 33-83% of (400 µg/ml) Gentamicin. Conclusions: To date, 9 RMAs have been identified that enhance the expression of functional C7 in a mutation-dependent manner in two different RDEB patient fibroblast backgrounds (R578X/R578X and R163X/R1683X-COL7A1). A further 6 RMAs have been identified that enhance the readthrough of C325X-LAMB3 in JEB patient keratinocytes. Based on the clinical trial conducted by us with topical gentamycin in 2017, Zikani’s RMAs achieve clinically significant levels of read-through for the treatment of recessive dystrophic and Junctional Epidermolysis Bullosa.

Keywords: epidermolysis bullosa, nonsense mutation, readthrough, ribosome modulation

Procedia PDF Downloads 95
494 The New World Kirkpatrick Model as an Evaluation Tool for a Publication Writing Programme

Authors: Eleanor Nel

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Research output is an indicator of institutional performance (and quality), resulting in increased pressure on academic institutions to perform in the research arena. Research output is further utilised to obtain research funding. Resultantly, academic institutions face significant pressure from governing bodies to provide evidence on the return for research investments. Research output has thus become a substantial discourse within institutions, mainly due to the processes linked to evaluating research output and the associated allocation of research funding. This focus on research outputs often surpasses the development of robust, widely accepted tools to additionally measure research impact at institutions. A publication writing programme, for enhancing research output, was launched at a South African university in 2011. Significant amounts of time, money, and energy have since been invested in the programme. Although participants provided feedback after each session, no formal review was conducted to evaluate the research output directly associated with the programme. Concerns in higher education about training costs, learning results, and the effect on society have increased the focus on value for money and the need to improve training, research performance, and productivity. Furthermore, universities rely on efficient and reliable monitoring and evaluation systems, in addition to the need to demonstrate accountability. While publishing does not occur immediately, achieving a return on investment from the intervention is critical. A multi-method study, guided by the New World Kirkpatrick Model (NWKM), was conducted to determine the impact of the publication writing programme for the period of 2011 to 2018. Quantitative results indicated a total of 314 academics participating in 72 workshops over the study period. To better understand the quantitative results, an open-ended questionnaire and semi-structured interviews were conducted with nine participants from a particular faculty as a convenience sample. The purpose of the research was to collect information to develop a comprehensive framework for impact evaluation that could be used to enhance the current design and delivery of the programme. The qualitative findings highlighted the critical role of a multi-stakeholder strategy in strengthening support before, during, and after a publication writing programme to improve the impact and research outputs. Furthermore, monitoring on-the-job learning is critical to ingrain the new skills academics have learned during the writing workshops and to encourage them to be accountable and empowered. The NWKM additionally provided essential pointers on how to link the results more effectively from publication writing programmes to institutional strategic objectives to improve research performance and quality, as well as what should be included in a comprehensive evaluation framework.

Keywords: evaluation, framework, impact, research output

Procedia PDF Downloads 74
493 Quantifying the Effects of Canopy Cover and Cover Crop Species on Water Use Partitioning in Micro-Sprinkler Irrigated Orchards in South Africa

Authors: Zanele Ntshidi, Sebinasi Dzikiti, Dominic Mazvimavi

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South Africa is a dry country and yet it is ranked as the 8th largest exporter of fresh apples (Malus Domestica) globally. Prime apple producing regions are in the Eastern and Western Cape Provinces of the country where all the fruit is grown under irrigation. Climate change models predict increasingly drier future conditions in these regions and the frequency and severity of droughts is expected to increase. For the sustainability and growth of the fruit industry it is important to minimize non-beneficial water losses from the orchard floor. The aims of this study were firstly to compare the water use of cover crop species used in South African orchards for which there is currently no information. The second aim was to investigate how orchard water use (evapotranspiration) was partitioned into beneficial (tree transpiration) and non-beneficial (orchard floor evaporation) water uses for micro-sprinkler irrigated orchards with different canopy covers. This information is important in order to explore opportunities to minimize non-beneficial water losses. Six cover crop species (four exotic and two indigenous) were grown in 2 L pots in a greenhouse. Cover crop transpiration was measured using the gravimetric method on clear days. To establish how water use was partitioned in orchards, evapotranspiration (ET) was measured using an open path eddy covariance system, while tree transpiration was measured hourly throughout the season (October to June) on six trees per orchard using the heat ratio sap flow method. On selected clear days, soil evaporation was measured hourly from sunrise to sunset using six micro-lysimeters situated at different wet/dry and sun/shade positions on the orchard floor. Transpiration of cover crops was measured using miniature (2 mm Ø) stem heat balance sap flow gauges. The greenhouse study showed that exotic cover crops had significantly higher (p < 0.01) average transpiration rates (~3.7 L/m2/d) than the indigenous species (~ 2.2 L/m²/d). In young non-bearing orchards, orchard floor evaporative fluxes accounted for more than 60% of orchard ET while this ranged from 10 to 30% in mature orchards with a high canopy cover. While exotic cover crops are preferred by most farmers, this study shows that they use larger quantities of water than indigenous species. This in turn contributes to a larger orchard floor evaporation flux. In young orchards non-beneficial losses can be minimized by adopting drip or short range micro-sprinkler methods that reduce the wetted soil fraction thereby conserving water.

Keywords: evapotranspiration, sap flow, soil evaporation, transpiration

Procedia PDF Downloads 383
492 Effect of Biostimulants to Control the Phelipanche ramosa L. Pomel in Processing Tomato Crop

Authors: G. Disciglio, G. Gatta, F. Lops, A. Libutti, A. Tarantino, E. Tarantino

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The experimental trial was carried out in open field at Foggia district (Apulia Region, Southern Italy), during the spring-summer season 2014, in order to evaluate the effect of four biostimulant products (RadiconÒ, Viormon plusÒ, LysodinÒ and SiaptonÒ 10L), compared with a control (no biostimulant), on the infestation of processing tomato crop (cv Dres) by the chlorophyll-lacking root parasite Phelipanche ramosa. Biostimulants consist in different categories of products (microbial inoculants, humic and fulvic acids, hydrolyzed proteins and aminoacids, seaweed extracts) which play various roles in plant growing, including the improvement of crop resistance and quali-quantitative characteristics of yield. The experimental trial was arranged according to a complete randomized block design with five treatments, each of one replicated three times. The processing tomato seedlings were transplanted on 5 May 2014. Throughout the crop cycle, P. ramosa infestation was assessed according to the number of emerged shoots (branched plants) counted in each plot, at 66, 78 and 92 day after transplanting. The tomato fruits were harvested at full-stage of maturity on 8 August 2014. From each plot, the marketable yield was measured and the quali-quantitative yield parameters (mean weight, dry matter content, colour coordinate, colour index and soluble solids content of the fruits) were determined. The whole dataset was tested according to the basic assumptions for the analysis of variance (ANOVA) and the differences between the means were determined using Tukey’s tests at the 5% probability level. The results of the study showed that none of the applied biostimulants provided a whole control of Phelipanche, although some positive effects were obtained from their application. To this respect, the RadiconÒ appeared to be the most effective in reducing the infestation of this root-parasite in tomato crop. This treatment also gave the higher tomato yield.

Keywords: biostimulant, control methods, Phelipanche ramosa, tomato crop

Procedia PDF Downloads 292
491 Embolism: How Changes in Xylem Sap Surface Tension Affect the Resistance against Hydraulic Failure

Authors: Adriano Losso, Birgit Dämon, Stefan Mayr

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In vascular plants, water flows from roots to leaves in a metastable state, and even a small perturbation of the system can lead a sudden transition from the liquid to the vapor phase, resulting in xylem embolism (cavitation). Xylem embolism, induced by drought stress and/or freezing stress is caused by the aspiration of gaseous bubbles into xylem conduits from adjacent gas-filled compartments through pit membrane pores (‘air seeding’). At water potentials less negative than the threshold for air seeding, the surface tension (γ) stabilizes the air-water interface and thus prevents air from passing the pit pores. This hold is probably also true for conifers, where this effect occurs at the edge of the sealed torus. Accordingly, it was experimentally demonstrated that γ influences air seeding, but information on the relevance of this effect under field conditions is missing. In this study, we analyzed seasonal changes in γ of the xylem sap in two conifers growing at the alpine timberline (Picea abies and Pinus mugo). In addition, cut branches were perfused (40 min perfusion at 0.004 MPa) with different γ solutions (i.e. distilled and degassed water, 2, 5 and 15% (v/v) ethanol-water solution corresponding to a γ of 74, 65, 55 and 45 mN m-1, respectively) and their vulnerability to drought-induced embolism analyzed via the centrifuge technique (Cavitron). In both species, xylem sap γ changed considerably (ca. 53-67 and ca. 50-68 mN m-1 in P. abies and P. cembra, respectively) over the season. Branches perfused with low γ solutions showed reduced resistance against drought-induced embolism in both species. A significant linear relationship (P < 0.001) between P12, P50 and P88 (i.e. water potential at 12, 50 and 88% of the loss of conductivity) and xylem sap γ was found. Based on this correlation, a variation in P50 between -3.10 and -3.83 MPa (P. abies) and between -3.21 and -4.11 MPa (P. mugo) over the season could be estimated. Results demonstrate that changes in γ of the xylem sap can considerably influence a tree´s resistance to drought-induced embolism. They indicate that vulnerability analyses, normally conducted at a γ near that of pure water, might often underestimate vulnerabilities under field conditions. For studied timberline conifers, seasonal changes in γ might be especially relevant in winter, when frost drought and freezing stress can lead to an excessive embolism.

Keywords: conifers, Picea abies, Pinus mugo, timberline

Procedia PDF Downloads 285
490 An Investigation into the Potential of Industrial Low Grade Heat in Membrane Distillation for Freshwater Production

Authors: Yehia Manawi, Ahmad Kayvanifard

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Membrane distillation is an emerging technology which has been used to produce freshwater and purify different types of aqueous mixtures. Qatar is an arid country where almost 100% of its freshwater demand is supplied through the energy-intensive thermal desalination process. The country’s need for water has reached an all-time high which stipulates finding an alternative way to augment freshwater without adding any drastic affect to the environment. The objective of this paper was to investigate the potential of using the industrial low grade waste heat to produce freshwater using membrane distillation. The main part of this work was conducting a heat audit on selected Qatari chemical industries to estimate the amounts of freshwater produced if such industrial waste heat were to be recovered. By the end of this work, the main objective was met and the heat audit conducted on the Qatari chemical industries enabled us to estimate both the amounts of waste heat which can be potentially recovered in addition to the amounts of freshwater which can be produced if such waste heat were to be recovered. By the end, the heat audit showed that around 605 Mega Watts of waste heat can be recovered from the studied Qatari chemical industries which resulted in a total daily production of 5078.7 cubic meter of freshwater. This water can be used in a wide variety of applications such as human consumption or industry. The amount of produced freshwater may look small when compared to that produced through thermal desalination plants; however, one must bear in mind that this water comes from waste and can be used to supply water for small cities or remote areas which are not connected to the water grid. The idea of producing freshwater from the two widely-available wastes (thermal rejected brine and waste heat) seems promising as less environmental and economic impacts will be associated with freshwater production which may in the near future augment the conventional way of producing freshwater currently being thermal desalination. This work has shown that low grade waste heat in the chemical industries in Qatar and perhaps the rest of the world can contribute to additional production of freshwater using membrane distillation without significantly adding to the environmental impact.

Keywords: membrane distillation, desalination, heat recovery, environment

Procedia PDF Downloads 314
489 Development of One-Pot Sequential Cyclizations and Photocatalyzed Decarboxylative Radical Cyclization: Application Towards Aspidospermatan Alkaloids

Authors: Guillaume Bélanger, Jean-Philippe Fontaine, Clémence Hauduc

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There is an undeniable thirst from organic chemists and from the pharmaceutical industry to access complex alkaloids with short syntheses. While medicinal chemists are interested in the fascinating wide range of biological properties of alkaloids, synthetic chemists are rather interested in finding new routes to access these challenging natural products of often low availability from nature. To synthesize complex polycyclic cores of natural products, reaction cascades or sequences performed one-pot offer a neat advantage over classical methods for their rapid increase in molecular complexity in a single operation. In counterpart, reaction cascades need to be run on substrates bearing all the required functional groups necessary for the key cyclizations. Chemoselectivity is thus a major issue associated with such a strategy, in addition to diastereocontrol and regiocontrol for the overall transformation. In the pursuit of synthetic efficiency, our research group developed an innovative one-pot transformation of linear substrates into bi- and tricyclic adducts applied to the construction of Aspidospermatan-type alkaloids. The latter is a rich class of indole alkaloids bearing a unique bridged azatricyclic core. Despite many efforts toward the synthesis of members of this family, efficient and versatile synthetic routes are still coveted. Indeed, very short, non-racemic approaches are rather scarce: for example, in the cases of aspidospermidine and aspidospermine, syntheses are all fifteen steps and over. We envisaged a unified approach to access several members of the Aspidospermatan alkaloids family. The key sequence features a highly chemoselective formamide activation that triggers a Vilsmeier-Haack cyclization, followed by an azomethine ylide generation and intramolecular cycloaddition. Despite the high density and variety of functional groups on the substrates (electron-rich and electron-poor alkenes, nitrile, amide, ester, enol ether), the sequence generated three new carbon-carbon bonds and three rings in a single operation with good yield and high chemoselectivity. A detailed study of amide, nucleophile, and dipolarophile variations to finally get to the successful combination required for the key transformation will be presented. To complete the indoline fragment of the natural products, we developed an original approach. Indeed, all reported routes to Aspidospermatan alkaloids introduce the indoline or indole early in the synthesis. In our work, the indoline needs to be installed on the azatricyclic core after the key cyclization sequence. As a result, typical Fischer indolization is not suited since this reaction is known to fail on such substrates. We thus envisaged a unique photocatalyzed decarboxylative radical cyclization. The development of this reaction as well as the scope and limitations of the methodology, will also be presented. The original Vilsmeier-Haack and azomethine ylide cyclization sequence as well as the new photocatalyzed decarboxylative radical cyclization will undoubtedly open access to new routes toward polycyclic indole alkaloids and derivatives of pharmaceutical interest in general.

Keywords: Aspidospermatan alkaloids, azomethine ylide cycloaddition, decarboxylative radical cyclization, indole and indoline synthesis, one-pot sequential cyclizations, photocatalysis, Vilsmeier-Haack Cyclization

Procedia PDF Downloads 73
488 Impure Water, a Future Disaster: A Case Study of Lahore Ground Water Quality with GIS Techniques

Authors: Rana Waqar Aslam, Urooj Saeed, Hammad Mehmood, Hameed Ullah, Imtiaz Younas

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This research has been conducted to assess the water quality in and around Lahore Metropolitan area on the basis of three different land uses, i.e. residential, commercial, and industrial land uses. For this, 29 sample sites have been selected on the basis of simple random sampling technique. Samples were collected at the source (WASA tube wells). The criteria for selecting sample sites are to have a maximum concentration of population in the selected land uses. The results showed that in the residential land use the proportion of nitrate and turbidity is at their highest level in the areas of Allama Iqbal Town and Samanabad Town. Commercial land use of Gulberg and Data Gunj Bakhsh Town have highest level of proportion of chlorides, calcium, TDS, pH, Mg, total hardness, arsenic and alkalinity. Whereas in industrial type of land use in Ravi and Wahga Town have the proportion of arsenic, Mg, nitrate, pH, and turbidity are at their highest level. The high rate of concentration of these parameters in these areas is basically due to the old and fractured pipelines that allow bacterial as well as physiochemical contaminants to contaminate the portable water at the sources. Furthermore, it is seen in most areas that waste water from domestic, industrial, as well as municipal sources may get easy discharge into open spaces and water bodies, like, cannels, rivers, lakes that seeps and become a part of ground water. In addition, huge dumps located in Lahore are becoming the cause of ground water contamination as when the rain falls, the water gets seep into the ground and impures the ground water quality. On the basis of the derived results with the help of Geo-spatial technology ACRGIS 9.3 Interpolation (IDW), it is recommended that water filtration plants must be installed with specific parameter control. A separate team for proper inspection has to be made for water quality check at the source. Old water pipelines must be replaced with the new pipelines, and safe water depth must be ensured at the source end.

Keywords: GIS, remote sensing, pH, nitrate, disaster, IDW

Procedia PDF Downloads 221
487 Carbon Nanofibers as the Favorite Conducting Additive for Mn₃O₄ Catalysts for Oxygen Reactions in Rechargeable Zinc-Air Battery

Authors: Augustus K. Lebechi, Kenneth I. Ozoemena

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Rechargeable zinc-air batteries (RZABs) have been described as one of the most viable next-generation ‘beyond-the-lithium-ion’ battery technologies with great potential for renewable energy storage. It is safe, with a high specific energy density (1086 Wh/kg), environmentally benign, and low-cost, especially in resource-limited African countries. For widespread commercialization, the sluggish oxygen reaction kinetics pose a major challenge that impedes the reversibility of the system. Hence, there is a need for low-cost and highly active bifunctional electrocatalysts. Manganese oxide catalysts on carbon conducting additives remain the best couple for the realization of such low-cost RZABs. In this work, hausmannite Mn₃O₄ nanoparticles were synthesized through the annealing method from commercial electrolytic manganese dioxide (EMD), multi-walled carbon nanotubes (MWCNTs) were synthesized via the chemical vapor deposition (CVD) method and carbon nanofibers (CNFs) were synthesized via the electrospinning process with subsequent carbonization. Both Mn₃O₄ catalysts and the carbon conducting additives (MWCNT and CNF) were thoroughly characterized using X-ray powder diffraction spectroscopy (XRD), scanning electron microscopy (SEM), thermogravimetry analysis (TGA) and X-ray photoelectron spectroscopy (XPS). Composite electrocatalysts (Mn₃O₄/CNT and Mn₃O₄/CNF) were investigated for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) in an alkaline medium. Using the established electrocatalytic modalities for evaluating the electrocatalytic performance of materials (including double layer, electrochemical active surface area, roughness factor, specific current density, and catalytic stability), CNFs proved to be the most efficient conducting additive material for the Mn₃O₄ catalyst. From the DFT calculations, the higher performance of the CNFs over the MWCNTs is related to the ability of the CNFs to allow for a more favorable distribution of the d-electrons of the manganese (Mn) and enhanced synergistic effect with Mn₃O₄ for weaker adsorption energies of the oxygen intermediates (O*, OH* and OOH*). In a proof-of-concept, Mn₃O₄/CNF was investigated as the air cathode for rechargeable zinc-air battery (RZAB) in a micro-3D-printed cell configuration. The RZAB showed good performance in terms of open circuit voltage (1.77 V), maximum power density (177.5 mW cm-2), areal-discharge energy and cycling stability comparable to Pt/C (20 wt%) + IrO2. The findings here provide fresh physicochemical perspectives on the future design and utility of CNFs for developing manganese-based RZABs.

Keywords: bifunctional electrocatalyst, oxygen evolution reaction, oxygen reduction reactions, rechargeable zinc-air batteries.

Procedia PDF Downloads 53
486 The Influence of Experiential Marketing on Customer Purchase Intention of Online Fashion Products

Authors: Marike Venter de Villiers, Alicia Kruger

Abstract:

The rapid development of the Internet has facilitated the proliferation of online stores. It has, therefore, become a pertinent issue for online retailers to provide the ultimate experience to customers in an attempt to maintain market share in this competitive landscape. Experiential marketing refers to the sensory dimensions that consumers experience when being faced with a purchase decision, such as getting them to sense, feel, think, act, and relate. The goal of experiential marketing is to provide a holistic experience for customers that allow them to engage in an activity where they may be motivated to purchase the concept behind the product. Creating a unique online experience holds several benefits to brands such as increased customer satisfaction, increased revisit intention, and higher levels of customer loyalty. Although several studies have explored the topic of experiential marketing in an online context, a lack of research exists on South African consumers, an emerging economy that is often overlooked globally. More specifically, the present study focused on professional females and their perceptions of experiential marketing when shopping for fashion products online. The main purpose of this study was to investigate the experiential factors that influence the online purchase intention of fashion products among female professionals. Furthermore, this study aimed to achieve the following objectives: firstly, to gain insight into key website characteristics that consumers value when shopping online for fashion products; secondly, to apply Pine and Gilmore’s (1989) Four Realms of an Experience (entertainment, education, esthetics, and escapism) to ground the study; and thirdly, to gain in-depth insight into the importance of these dimensions and identifying sub-categories that fashion marketers can use to enhance consumers’ online experience. By means of a qualitative study, a focus group was conducted comprising six professional females by using semi-structured questions. Respondents were selected using convenience sampling, and the results were analyzed using thematic analysis. The present research suggests that three of the four realms of experience influence purchase intention of fashion products online, namely, escapism, esthetics, and education. The fourth dimension, pleasure, was present but to a lesser degree. In other words, ‘escapism’ provides online shoppers with a sense of emotional and intellectual pleasure, while ‘esthetics’ refers to the website design, functionality, and product range, and ‘education’ comprises the product information such as the quality, fabric, price and available sizes. The findings of this study provide fashion marketers with insight into how they can maximize on experiential marketing when selling fashion products online. It further provides strategies and techniques for creating an enhanced online experience that ultimately may lead to increased purchase intention.

Keywords: experiential marketing, fashion, online, retail

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485 Phytoremediation of Arsenic-Contaminated Soil and Recovery of Valuable Arsenic Products

Authors: Valentine C. Eze, Adam P. Harvey

Abstract:

Contamination of groundwater and soil by heavy metals and metalloids through anthropogenic activities and natural occurrence poses serious environmental challenges globally. A possible solution to this problem is through phytoremediation of the contaminants using hyper-accumulating plants. Conventional phytoremediation treats the contaminated hyper-accumulator biomass as a waste stream which adds no value to the heavy metal(loid)s decontamination process. This study investigates strategies for remediation of soil contaminated with arsenic and the extractive chemical routes for recovery of arsenic and phosphorus from the hyper-accumulator biomass. Pteris cretica ferns species were investigated for their uptake of arsenic from soil containing 200 ± 3ppm of arsenic. The Pteris cretica ferns were shown to be capable of hyper-accumulation of arsenic, with maximum accumulations of about 4427 ± 79mg to 4875 ± 96mg of As per kg of the dry ferns. The arsenic in the Pteris cretica fronds was extracted into various solvents, with extraction efficiencies of 94.3 ± 2.1% for ethanol-water (1:1 v/v), 81.5 ± 3.2% for 1:1(v/v) methanol-water, and 70.8 ± 2.9% for water alone. The recovery efficiency of arsenic from the molybdic acid complex process 90.8 ± 5.3%. Phosphorus was also recovered from the molybdic acid complex process at 95.1 ± 4.6% efficiency. Quantitative precipitation of Mg₃(AsO₄)₂ and Mg₃(PO₄)₂ occurred in the treatment of the aqueous solutions of arsenic and phosphorus after stripping at pH of 8 – 10. The amounts of Mg₃(AsO₄)₂ and Mg₃(PO₄)₂ obtained were 96 ± 7.2% for arsenic and 94 ± 3.4% for phosphorus. The arsenic nanoparticles produced from the Mg₃(AsO₄)₂ recovered from the biomass have the average particles diameter of 45.5 ± 11.3nm. A two-stage reduction process – a first step pre-reduction of As(V) to As(III) with L-cysteine, followed by NaBH₄ reduction of the As(III) to As(0), was required to produced arsenic nanoparticles from the Mg₃(AsO₄)₂. The arsenic nanoparticles obtained are potentially valuable for medical applications, while the Mg₃(AsO₄)₂ could be used as an insecticide. The phosphorus contents of the Pteris cretica biomass was recovered as phosphomolybdic acid complex and converted to Mg₃(PO₄)₂, which could be useful in productions of fertilizer. Recovery of these valuable products from phytoremediation biomass would incentivize and drive commercial industries’ participation in remediation of contaminated lands.

Keywords: phytoremediation, Pteris cretica, hyper-accumulator, solvent extraction, molybdic acid process, arsenic nanoparticles

Procedia PDF Downloads 312