Search results for: weight growth
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9536

Search results for: weight growth

7406 The Effect of Pre-Cracks on Structural Strength of the Nextel Fibers: A Multiscale Modeling Approach

Authors: Seyed Mohammad Mahdi Zamani, Kamran Behdinan

Abstract:

In this study, a multiscale framework is performed to model the strength of Nextel fibers in presence of an atomistic scale pre-crack at finite temperatures. The bridging cell method (BCM) is the multiscale technique applied in this study, which decomposes the system into the atomistic, bridging and continuum domains; solves the whole system in a finite element framework; and incorporates temperature dependent calculations. Since Nextel is known to be structurally stable and retain 70% of its initial strength up to 1100°C; simulations are conducted at both of the room temperatures, 25°C, and fire temperatures, 1200°C. Two cases are modeled for a pre-crack present in either phases of alumina or mullite of the Nextel structure. The materials’ response is studied with respect to deformation behavior and ultimate tensile strength. Results show different crack growth trends for the two cases, and as the temperature increases, the crack growth resistance and material’s strength decrease.

Keywords: Nextel fibers, multiscale modeling, pre-crack, ultimate tensile strength

Procedia PDF Downloads 400
7405 Effect of Upper Face Sheet Material on Flexural Strength of Polyurethane Foam Hybrid Sandwich Material

Authors: M. Atef Gabr, M. H. Abdel Latif, Ramadan El Gamsy

Abstract:

Sandwich panels comprise a thick, light-weight plastic foam such as polyurethane (PU) sandwiched between two relatively thin faces. One or both faces may be flat, lightly profiled or fully profiled. Until recently sandwich panel construction in Egypt has been widely used in cold-storage buildings, cold trucks, prefabricated buildings and insulation in construction. Recently new techniques are used in mass production of Sandwich Materials such as Reaction Injection Molding (RIM) and Vacuum bagging technique. However, in recent times their use has increased significantly due to their widespread structural applications in building systems. Structural sandwich panels generally used in Egypt comprise polyurethane foam core and thinner (0.42 mm) and high strength about 550 MPa (yield strength) flat steel faces bonded together using separate adhesives and By RIM technique. In this paper, we will use a new technique in sandwich panel preparation by using different face sheet materials in combination with polyurethane foam to form sandwich panel structures. Previously, PU Foam core with same thin 2 faces material was used, but in this work, we use different face materials and thicknesses for the upper face sheet such as Galvanized steel sheets (G.S),Aluminum sheets (Al),Fiberglass sheets (F.G) and Aluminum-Rubber composite sheets (Al/R) with polyurethane foam core 10 mm thickness and 45 Kg/m3 Density and Galvanized steel as lower face sheet. Using Aluminum-Rubber composite sheets as face sheet is considered a hybrid composite sandwich panel which is built by Hand-Layup technique by using PU glue as adhesive. This modification increases the benefits of the face sheet that will withstand different working environments with relatively small increase in its weight and will be useful in several applications. In this work, a 3-point bending test is used assistant professor to measure the most important factor in sandwich materials that is strength to weight ratio(STW) for different combinations of sandwich structures and make a comparison to study the effect of changing the face sheet material on the mechanical behavior of PU sandwich material. Also, the density of the different prepared sandwich materials will be measured to obtain the specific bending strength.

Keywords: hybrid sandwich panel, mechanical behavior, PU foam, sandwich panel, 3-point bending, flexural strength

Procedia PDF Downloads 295
7404 The Checkout and Separation of Environmental Hazards of the Range Overlooking the Meshkin City

Authors: F. Esfandyari Darabad, Z. Samadi

Abstract:

Natural environments have always been affected by one of the most important natural hazards, which is called, the mass movements that cause instability. Identifying the unstable regions and separating them so as to detect and determine the risk of environmental factors is one of the important issues in mountainous areas development. In this study, the northwest of Sabalan hillsides overlooking the Meshkin city and the surrounding area of that have been delimitated, in order to analyze the range processes such as landslides and debris flows based on structural and geomorphological conditions, by means of using GIS. This area due to the high slope of the hillsides and height of the region and the poor localization of roads and so because of them destabilizing the ranges own an inappropriate situation. This study is done with the purpose of identifying the effective factors in the range motion and determining the areas with high potential for zoning these movements by using GIS. The results showed that the most common range movements in the area, are debris flows, rocks falling and landslides. The effective factors in each one of the mass movements, considering a small amount of weight for each factor, the weight map of each factor and finally, the map of risk zoning for the range movements were provided. Based on the zoning map resulted in the study area, the risking level of damaging has specified into the four zones of very high risk, high risk, medium risk, low risk, in which areas with very high and high risk are settled near the road and along the Khyav river and in the  mountainous district.

Keywords: debris flow, environmental hazards, GIS, landslide

Procedia PDF Downloads 508
7403 Longitudinal Changes in Body Composition in Subjects with Diabetes Who Received Low-Carbohydrate Diet Education: The Effect of Age and Sex

Authors: Hsueh-Ching Wu

Abstract:

Aims: This study investigated the longitudinal changes in BC were evaluated in patients with T2D who received carbohydrate-restricted diet education (CRDE), and the effects of age and sex on BC were analyzed. Design: This retrospective observational study was conducted between 2018 and 2021. A total of 6164 T2D patients were analyzed. Subjects with T2D who received CRDE (daily carbohydrate intake: 26-45%). A hierarchical linear model (HLM) was used to estimate the change amount and rate of change for the following variables in each group: body weight (BW), body mass index (BMI), body fat mass (BFM), percent body fat (PBF), appendicular skeletal muscle mass (ASM), and skeletal muscle index (SMI). Results: The BW, BMI, ASM, SMI and BFM of T2D patients who received CRDE for 3 years decreased with increasing age; PBF showed the opposite trend. The changes in BW, BMI, ASM, and SMI of patients older than 65 years were higher than those of patients younger than 65 years, and the annual rate of decline for males was higher than that for females. The annual change in BFM and PBF for both sexes changed from a downward trend before the age of 65 to a slow increase after the age of 65, and the slow increase rate for women was higher than that for men. Conclusion: Changes in body composition are associated with age and sex. BW and muscle tissue decrease with age, and attention must be paid to the rebound of adipose tissue after middle age. Patient or Public Contribution: The patient agreed to participate in a retrospective chart review during in the study period.

Keywords: body weight, body composition, carbohydrate-restricted diet, nursing, type 2 diabetes

Procedia PDF Downloads 50
7402 Comparison of Polyphonic Profile of a Berry from Two Different Sources, Using an Optimized Extraction Method

Authors: G. Torabian, A. Fathi, P. Valtchev, F. Dehghani

Abstract:

The superior polyphenol content of Sambucus nigra berries has high health potentials for the production of nutraceutical products. Numerous factors influence the polyphenol content of the final products including the berries’ source and the subsequent processing production steps. The aim of this study is to compare the polyphenol content of berries from two different sources and also to optimise the polyphenol extraction process from elderberries. Berries from source B obtained more acceptable physical properties than source A; a single berry from source B was double in size and weight (both wet and dry weight) compared with a source A berry. Despite the appropriate physical characteristics of source B berries, their polyphenolic profile was inferior; as source A berries had 2.3 fold higher total anthocyanin content, and nearly two times greater total phenolic content and total flavonoid content compared to source B. Moreover, the result of this study showed that almost 50 percent of the phenolic content of berries are entrapped within their skin and pulp that potentially cannot be extracted by press juicing. To address this challenge and to increase the total polyphenol yield of the extract, we used cold-shock blade grinding method to break the cell walls. The result of this study showed that using cultivars with higher phenolic content as well as using the whole fruit including juice, skin and pulp can increase polyphenol yield significantly; and thus, may boost the potential of using elderberries as therapeutic products.

Keywords: different sources, elderberry, grinding, juicing, polyphenols

Procedia PDF Downloads 280
7401 Heat Forging Analysis Method on Blank Consist of Two Metals

Authors: Takashi Ueda, Shinichi Enoki

Abstract:

Forging parts is used to automobiles. Because they have high strength and it is possible to press them into complicated shape. When it is possible to manufacture hollow forging parts, it leads to reduce weight of the automobiles. But, hollow forging parts are confined to axisymmetrical shape. Hollow forging parts that were pressed to complicated shape are expected. Therefore, we forge a blank that aluminum alloy was inserted in stainless steel. After that, we can provide complex forging parts that are reduced weight, if it is possible to be melted the aluminum alloy away by using different of melting points. It is necessary to establish heat forging analysis method on blank consist of stainless steel and aluminum alloy. Because, this forging is different from conventional forging and this technology is not confirmed. In this study, we compared forging experiment with numerical analysis on the view point of forming load and shape after forming and establish how to set the material temperatures of two metals and material property of stainless steel on the analysis method. Consequently, temperature difference of stainless steel and aluminum alloy was obtained by experiment. We got material property of stainless steel on forging experimental by compression tests. We had compared numerical analysis that was used the temperature difference of two metals and the material property of stainless steel on forging experimental with forging experiment. Forging analysis method on blank consist of two metals was established by result of numerical analysis having agreed with result of forging experiment.

Keywords: forging, lightweight, analysis, hollow

Procedia PDF Downloads 402
7400 Silicon Nanoparticles and Irradiated Chitosan: Sustainable Elicitors for PS II Activity and Antioxidant Mediated Plant Immunity

Authors: Mohammad Mukarram, M. Masroor A. Khan, Daniel Kurjak, Marek Fabrika

Abstract:

Lemongrass (Cymbopogon flexuosus (Steud.) Wats) is an aromatic grass with great industrial potential. It is cultivated for its essential oil (EO), which has great economic value due to its numerous medicinal, cosmetic, and culinary applications. The present study had the goal to evaluate whether the combined application of silicon nanoparticles (SiNPs) 150 mg L⁻¹ and irradiated chitosan (ICH) 120 mg L⁻¹ can upgrade lemongrass crop and render enhanced growth and productivity. The analyses of growth and photosynthetic parameters, leaf-nitrogen, and reactive oxygen species metabolism, as well as the content of total essential oil, indicated that combined foliar sprays of SiNPs and ICH can significantly (p≤0.05) trigger a general activation of lemongrass metabolism. Overall, the data indicate that concomitant SiNPs and ICH application elicit lemongrass physiology and defence system, and opens new possibilities for their biotechnological application on other related plant species with agronomic potential.

Keywords: photosynthesis, Cymbopogon, antioxidant metabolism, essential oil, ROS, nanoparticles, polysaccharides

Procedia PDF Downloads 67
7399 Study of Nucleation and Growth Processes of Ettringite in Supersaturated Diluted Solutions

Authors: E. Poupelloz, S. Gauffinet

Abstract:

Ettringite Ca₆Al₂(SO₄)₃(OH)₁₂26H₂O is one of the major hydrates formed during cement hydration. Ettringite forms in Portland cement from the reaction between tricalcium aluminate Ca₃Al₂O₆ and calcium sulfate. Ettringite is also present in calcium sulfoaluminate cement in which it is the major hydrate, formed by the reaction between yeelimite Ca₄(AlO₂)₆SO₄ and calcium sulfate. About the formation of ettringite, numerous results are available in the literature even if some issues are still under discussion. However, almost all published work about ettringite was done on cementitious systems. Yet in cement, hydration reactions are very complex, the result of dissolution-precipitation processes and are submitted to various interactions. Understanding the formation process of a phase alone, here ettringite, is the first step to later understand the much more complex reactions happening in cement. This study is crucial for the comprehension of early cement hydration and physical behavior. Indeed formation of hydrates, in particular, ettringite, will have an influence on the rheological properties of the cement paste and on the need for admixtures. To make progress toward the understanding of existing phenomena, a specific study of nucleation and growth processes of ettringite was conducted. First ettringite nucleation was studied in ionic aqueous solutions, with controlled but different experimental conditions, as different supersaturation degrees (β), different pH or presence of exogenous ions. Through induction time measurements, interfacial ettringite crystals solution energies (γ) were determined. Growth of ettringite in supersaturated solutions was also studied through chain crystallization reactions. Specific BET surface area measurements and Scanning Electron Microscopy observations seemed to prove that growth process is favored over the nucleation process when ettringite crystals are initially present in a solution with a low supersaturation degree. The influence of stirring on ettringite formation was also investigated. Observation was made that intensity and nature of stirring have a high influence on the size of ettringite needles formed. Needle sizes vary from less than 10µm long depending on the stirring to almost 100µm long without any stirring. During all previously mentioned experiments, initially present ions are consumed to form ettringite in such a way that the supersaturation degree with regard to ettringite is decreasing over time. To avoid this phenomenon a device compensating the drop of ion concentrations by adding some more solutions, and therefore always have constant ionic concentrations, was used. This constant β recreates the conditions of the beginning of cement paste hydration, when the dissolution of solid reagents compensates the consumption of ions to form hydrates. This device allowed the determination of the ettringite precipitation rate as a function of the supersaturation degree β. Taking samples at different time during ettringite precipitation and doing BET measurements allowed the determination of the interfacial growth rate of ettringite in m²/s. This work will lead to a better understanding and control of ettringite formation alone and thus during cements hydration. This study will also ultimately define the impact of ettringite formation process on the rheology of cement pastes at early age, which is a crucial parameter from a practical point of view.

Keywords: cement hydration, ettringite, morphology of crystals, nucleation-growth process

Procedia PDF Downloads 114
7398 Direct Growth Rates of the Information Model for Traffic at the Service of Sustainable Development of Tourism in Dubrovacko-Neretvanska County 2014-2020

Authors: Vinko Viducic, Jelena Žanic Mikulicic, Maja Racic, Kristina Sladojevic

Abstract:

The research presented in this paper has been focused on analyzing the impact of traffic on the sustainable development of tourism in Croatia's Dubrovacko-Neretvanska County by the year 2020, based on the figures and trends reported in 2014 and using the relevant variables that characterise the synergy of traffic and tourism in, speaking from the geographic viewpoint, the most problematic county in the Republic of Croatia. The basic hypothesis has been confirmed through scientifically obtained research results, through the quantification of the model's variables and the direct growth rates of the designed model. On the basis of scientific insights into the sustainable development of traffic and tourism in Dubrovacko-Neretvanska County, it is possible to propose a new information model for traffic at the service of the sustainable development of tourism in the County for the period 2014-2020.

Keywords: environment protection, hotel industry, private sector, quantification

Procedia PDF Downloads 265
7397 Changes in Amino Acids Content in Muscle of European Eel (Anguilla anguilla) in Relation to Body Size

Authors: L. Gómez-Limia, I. Franco, T. Blanco, S. Martínez

Abstract:

European eels (Anguilla anguilla) belong to Anguilliformes order and Anguillidae family. They are generally classified as warm-water fish. Eels have a great commercial value in Europe and Asian countries. Eels can reach high weights, although their commercial size is relatively low in some countries. The capture of larger eels would facilitate the recovery of the species, as well as having a greater number of either glass eels or elvers for aquaculture. In the last years, the demand and the price of eels have increased significantly. However, European eel is considered critically endangered by the International Union for the Conservation of Nature (IUCN) Red List. The biochemical composition of fishes is an important aspect of quality and affects the nutritional value and consumption quality of fish. In addition, knowing this composition can help predict an individual’s condition for their recovery. Fish is known to be important source of protein rich in essential amino acids. However, there is very little information about changes in amino acids composition of European eels with increase in size. The aim of this study was to evaluate the effect of two different weight categories on the amino acids content in muscle tissue of wild European eels. European eels were caught in River Ulla (Galicia, NW Spain), during winter. The eels were slaughtered in ice water immersion. Then, they were purchased and transferred to the laboratory. The eels were subdivided into two groups, according to the weight. The samples were kept frozen (-20 °C) until their analysis. Frozen eels were defrosted and the white muscle between the head and the anal hole. was extracted, in order to obtain amino acids composition. Thirty eels for each group were used. Liquid chromatography was used for separation and quantification of amino a cids. The results conclude that the eels are rich in glutamic acid, leucine, lysine, threonine, valine, isoleucine and phenylalanine. The analysis showed that there are significant differences (p < 0.05) among the eels with different sizes. Histidine, threonine, lysine, hydroxyproline, serine, glycine, arginine, alanine and proline were higher in small eels. European eels muscle presents between 45 and 46% of essential amino acids in the total amino acids. European eels have a well-balanced and high quality protein source in the respect of E/NE ratio. However, eels with higher weight showed a better ratio of essential and non-essential amino acid.

Keywords: European eels, amino acids, HPLC, body size

Procedia PDF Downloads 90
7396 Calibration and Validation of the Aquacrop Model for Simulating Growth and Yield of Rain-Fed Sesame (Sesamum Indicum L.) Under Different Soil Fertility Levels in the Semi-arid Areas of Tigray, Ethiopia

Authors: Abadi Berhane, Walelign Worku, Berhanu Abrha, Gebre Hadgu

Abstract:

Sesame is an important oilseed crop in Ethiopia, which is the second most exported agricultural commodity next to coffee. However, there is poor soil fertility management and a research-led farming system for the crop. The AquaCrop model was applied as a decision-support tool, which performs a semi-quantitative approach to simulate the yield of crops under different soil fertility levels. The objective of this experiment was to calibrate and validate the AquaCrop model for simulating the growth and yield of sesame under different nitrogen fertilizer levels and to test the performance of the model as a decision-support tool for improved sesame cultivation in the study area. The experiment was laid out as a randomized complete block design (RCBD) in a factorial arrangement in the 2016, 2017, and 2018 main cropping seasons. In this experiment, four nitrogen fertilizer rates, 0, 23, 46, and 69 Kg/ha nitrogen, and three improved varieties (Setit-1, Setit-2, and Humera-1). In the meantime, growth, yield, and yield components of sesame were collected from each treatment. Coefficient of determination (R2), Root mean square error (RMSE), Normalized root mean square error (N-RMSE), Model efficiency (E), and Degree of agreement (D) were used to test the performance of the model. The results indicated that the AquaCrop model successfully simulated soil water content with R2 varying from 0.92 to 0.98, RMSE 6.5 to 13.9 mm, E 0.78 to 0.94, and D 0.95 to 0.99, and the corresponding values for AB also varied from 0.92 to 0.98, 0.33 to 0.54 tons/ha, 0.74 to 0.93, and 0.9 to 0.98, respectively. The results on the canopy cover of sesame also showed that the model acceptably simulated canopy cover with R2 varying from 0.95 to 0.99 and a RMSE of 5.3 to 8.6%. The AquaCrop model was appropriately calibrated to simulate soil water content, canopy cover, aboveground biomass, and sesame yield; the results indicated that the model adequately simulated the growth and yield of sesame under the different nitrogen fertilizer levels. The AquaCrop model might be an important tool for improved soil fertility management and yield enhancement strategies of sesame. Hence, the model might be applied as a decision-support tool in soil fertility management in sesame production.

Keywords: aquacrop model, normalized water productivity, nitrogen fertilizer, canopy cover, sesame

Procedia PDF Downloads 55
7395 The Effect of Treated Waste-Water on Compaction and Compression of Fine Soil

Authors: M. Attom, F. Abed, M. Elemam, M. Nazal, N. ElMessalami

Abstract:

—The main objective of this paper is to study the effect of treated waste-water (TWW) on the compaction and compressibility properties of fine soil. Two types of fine soils (clayey soils) were selected for this study and classified as CH soil and Cl type of soil. Compaction and compressibility properties such as optimum water content, maximum dry unit weight, consolidation index and swell index, maximum past pressure and volume change were evaluated using both tap and treated waste water. It was found that the use of treated waste water affects all of these properties. The maximum dry unit weight increased for both soils and the optimum water content decreased as much as 13.6% for highly plastic soil. The significant effect was observed in swell index and swelling pressure of the soils. The swell indexed decreased by as much as 42% and 33% for highly plastic and low plastic soils, respectively, when TWW is used. Additionally, the swelling pressure decreased by as much as 16% for both soil types. The result of this research pointed out that the use of treated waste water has a positive effect on compaction and compression properties of clay soil and promise for potential use of this water in engineering applications. Keywords—Consolidation, proctor compaction, swell index, treated waste-water, volume change.

Keywords: consolidation, proctor compaction, swell index, treated waste-water, volume change

Procedia PDF Downloads 248
7394 Communication through Offline and Online Social Network of Thai Football Premier League Supporters

Authors: Krisana Chueachainat

Abstract:

The study is about the identity, typology and symbol using in communication through offline and online social network of each Thai football Premier League supporters. Also, study is about the factors that affected the sport to become the growing business and the communication factors that play the important role in the growth of the sport business. The Thai Premier League communicated with supporters in order to show the identity of each supporter and club in different ways. The expression of the identity was shown through online social network and offline told other people who they were. The study also about the factor that impacted the roles and communication factors that make football become the growing business. The factor that impact to the growth of football to the business, if clubs can action, the sport business would be to higher level and also push Thailand’s football to be effective and equal to other countries.

Keywords: online social network, offline social network, Thai football, supporters

Procedia PDF Downloads 289
7393 Numerical Modelling and Experiment of a Composite Single-Lap Joint Reinforced by Multifunctional Thermoplastic Composite Fastener

Authors: Wenhao Li, Shijun Guo

Abstract:

Carbon fibre reinforced composites are progressively replacing metal structures in modern civil aircraft. This is because composite materials have large potential of weight saving compared with metal. However, the achievement to date of weight saving in composite structure is far less than the theoretical potential due to many uncertainties in structural integrity and safety concern. Unlike the conventional metallic structure, composite components are bonded together along the joints where structural integrity is a major concern. To ensure the safety, metal fasteners are used to reinforce the composite bonded joints. One of the solutions for a significant weight saving of composite structure is to develop an effective technology of on-board Structural Health Monitoring (SHM) System. By monitoring the real-life stress status of composite structures during service, the safety margin set in the structure design can be reduced with confidence. It provides a means of safeguard to minimize the need for programmed inspections and allow for maintenance to be need-driven, rather than usage-driven. The aim of this paper is to develop smart composite joint. The key technology is a multifunctional thermoplastic composite fastener (MTCF). The MTCF will replace some of the existing metallic fasteners in the most concerned locations distributed over the aircraft composite structures to reinforce the joints and form an on-board SHM network system. Each of the MTCFs will work as a unit of the AU and AE technology. The proposed MTCF technology has been patented and developed by Prof. Guo in Cranfield University, UK in the past a few years. The manufactured MTCF has been successfully employed in the composite SLJ (Single-Lap Joint). In terms of the structure integrity, the hybrid SLJ reinforced by MTCF achieves 19.1% improvement in the ultimate failure strength in comparison to the bonded SLJ. By increasing the diameter or rearranging the lay-up sequence of MTCF, the hybrid SLJ reinforced by MTCF is able to achieve the equivalent ultimate strength as that reinforced by titanium fastener. The predicted ultimate strength in simulation is in good agreement with the test results. In terms of the structural health monitoring, a signal from the MTCF was measured well before the load of mechanical failure. This signal provides a warning of initial crack in the joint which could not be detected by the strain gauge until the final failure.

Keywords: composite single-lap joint, crack propagation, multifunctional composite fastener, structural health monitoring

Procedia PDF Downloads 150
7392 Mitigation Measures for the Acid Mine Drainage Emanating from the Sabie Goldfield: Case Study of the Nestor Mine

Authors: Rudzani Lusunzi, Frans Waanders, Elvis Fosso-Kankeu, Robert Khashane Netshitungulwana

Abstract:

The Sabie Goldfield has a history of gold mining dating back more than a century. Acid mine drainage (AMD) from the Nestor mine tailings storage facility (MTSF) poses a serious threat to the nearby ecosystem, specifically the Sabie River system. This study aims at developing mitigation measures for the AMD emanating from the Nestor MTSF using materials from the Glynns Lydenburg MTSF. The Nestor MTSF (NM) and the Glynns Lydenburg MTSF (GM) each provided about 20 kg of bulk composite samples. Using samples from the Nestor MTSF and the Glynns Lydenburg MTSF, two mixtures were created. MIX-A is a mixture that contains 25% weight percent (GM) and 75% weight percent (NM). MIX-B is the name given to the second mixture, which contains 50% AN and 50% AG. The same static test, i.e., acid–base accounting (ABA), net acid generation (NAG), and acid buffering characteristics curve (ABCC) was used to estimate the acid-generating probabilities of samples NM and GM for MIX-A and MIX-B. Furthermore, the mineralogy of the Nestor MTSF samples consists of the primary acid-producing mineral pyrite as well as the secondary minerals ferricopiapite and jarosite, which are common in acidic conditions. The Glynns Lydenburg MTSF samples, on the other hand, contain primary acid-neutralizing minerals calcite and dolomite. Based on the assessment conducted, materials from the Glynns Lydenburg are capable of neutralizing AMD from Nestor MTSF. Therefore, the alkaline tailings materials from the Glynns Lydenburg MTSF can be used to rehabilitate the acidic Nestor MTSF.

Keywords: Nestor Mine, acid mine drainage, mitigation, Sabie River system

Procedia PDF Downloads 67
7391 Foreign Direct Investment, International Trade and Environment in Bangladesh: An Empirical Study

Authors: Shilpi Tripathi

Abstract:

After independence, Bangladesh had to learn to survive on its own without any economic crutches (aid). Foreign direct investment (FDI) became a crucial economic tool for the country to become economically independent. The government started removing restrictions to encourage foreign investment, economic growth, international trade, and the environment. FDI is considered as a way to bridge the saving-investment gap, reduce poverty, balance trade, create jobs for its vast labour force, increase foreign exchange earnings and acquire new modern technology and management skills in the country. At the same time, spillovers of foreign investments in Bangladesh, such as low wages (compared to laborers of developed countries), poor working conditions and unbridled exploitation of the domestic resources, environmental externalities, etc., cannot be ignored. The most important adverse implications of FDI inflows noticed are the environmental problems, which are further impacting the health and society of the country. This paper empirically studies the relationship between FDI, economic growth, international trade (exports and Imports), and the environment since 1996. The first part of the paper focuses on the background and trends of FDI, GDP, trade, and environment (CO₂). The second part focuses on the literature review on the relationship between all the variables. The last part of the paper examines the results of empirical analysis like co-integration and Granger causality. The findings of the paper reveal that a uni-directional relationship exists between FDI, CO₂, and international trade (exports and imports). The direction of the causality reveals that FDI inflow is one of the major contributors to high-volume international trade. At the same time, FDI and international trade both are contributing to carbon emissions in Bangladesh. The paper concludes with the policy recommendations that will ensure environmentally friendly trade, investment, and growth in Bangladesh for the future.

Keywords: foreign direct investment, GDP, international trade, CO₂, Granger causality, environment

Procedia PDF Downloads 162
7390 Performance Comparison of Different Regression Methods for a Polymerization Process with Adaptive Sampling

Authors: Florin Leon, Silvia Curteanu

Abstract:

Developing complete mechanistic models for polymerization reactors is not easy, because complex reactions occur simultaneously; there is a large number of kinetic parameters involved and sometimes the chemical and physical phenomena for mixtures involving polymers are poorly understood. To overcome these difficulties, empirical models based on sampled data can be used instead, namely regression methods typical of machine learning field. They have the ability to learn the trends of a process without any knowledge about its particular physical and chemical laws. Therefore, they are useful for modeling complex processes, such as the free radical polymerization of methyl methacrylate achieved in a batch bulk process. The goal is to generate accurate predictions of monomer conversion, numerical average molecular weight and gravimetrical average molecular weight. This process is associated with non-linear gel and glass effects. For this purpose, an adaptive sampling technique is presented, which can select more samples around the regions where the values have a higher variation. Several machine learning methods are used for the modeling and their performance is compared: support vector machines, k-nearest neighbor, k-nearest neighbor and random forest, as well as an original algorithm, large margin nearest neighbor regression. The suggested method provides very good results compared to the other well-known regression algorithms.

Keywords: batch bulk methyl methacrylate polymerization, adaptive sampling, machine learning, large margin nearest neighbor regression

Procedia PDF Downloads 293
7389 Dynamic Effects of Energy Consumption, Economic Growth, International Trade and Urbanization on Environmental Degradation in Nigeria

Authors: Abdulkarim Yusuf

Abstract:

Motivation: A crucial but difficult goal for governments and policymakers in Nigeria in recent years has been the sustainability of economic growth. This goal must be accomplished by regulating or lowering greenhouse gas emissions, which calls for switching to a low- or zero-carbon production system. The lack of in-depth empirical studies on the environmental impact of socioeconomic variables on Nigeria and a number of unresolved issues from earlier research is what led to the current study. Objective: This study fills an important empirical gap by investigating the existence of an Environmental Kuznets Curve hypothesis and the long and short-run dynamic impact of socioeconomic variables on ecological sustainability in Nigeria. Data and method: Annual time series data covering the period 1980 to 2020 and the Autoregressive Distributed Lag technique in the presence of structural breaks were adopted for this study. Results: The empirical findings support the existence of the environmental Kuznets curve hypothesis for Nigeria in the long and short run. Energy consumption and total import exacerbate environmental deterioration in the long and short run, whereas total export improves environmental quality in the long and short run. Financial development, which contributed to a conspicuous decrease in the level of environmental destruction in the long run, escalated it in the short run. In contrast, urbanization caused a significant increase in environmental damage in the long run but motivated a decrease in biodiversity loss in the short run. Implications: The government, policymakers, and all energy stakeholders should take additional measures to ensure the implementation and diversification of energy sources to accommodate more renewable energy sources that emit less carbon in order to promote efficiency in Nigeria's production processes and lower carbon emissions. In order to promote the production and trade of environmentally friendly goods, they should also revise and strengthen environmental policies. With affordable, dependable, and sustainable energy use for higher productivity and inclusive growth, Nigeria will be able to achieve its long-term development goals of good health and wellbeing.

Keywords: economic growth, energy consumption, environmental degradation, environmental Kuznets curve, urbanization, Nigeria

Procedia PDF Downloads 37
7388 Antimicrobial Effect of Natamycin against Food Spoilage Fungi and Yeast Contaminated Fermented Foods

Authors: Pervin Basaran Akocak

Abstract:

Food antimicrobials are compounds that are incorporated into food matrixes in order to cause death or delay the growth of spoilage or pathogenic microorganisms. As a result, microbiological deterioration is prevented throughout storage and food distribution. In this study, the effect of natural antimycotic natamycin (C33H47NO13, with a molecular mass of 665.725), a GRAS (Generally Recognized As Safe) commercial compound produced by different strains of Streptomyces sp., was tested against various fermented food contamination fungi and yeast species. At the concentration of 100 µg/ml, natamycin exhibited stronger antifungal activity against fungi than yeast species tested. The exposure time of natamycin for complete inhibition of the species tested were found to be between 100-180 min at 300-750 µg/ml concentration. SEM observations of fungal species demonstrated that natamycin distorted and damaged the conidia and hyphae by inhibiting spore germination and mycelial growth. Natamycin can be considered as a potential candidate in hurdle food treatments for preventing fungal and yeast invasion and resulting deterioration of fermented products.

Keywords: natamycin, antifungal, fermented food, food spoilage fungi

Procedia PDF Downloads 499
7387 Anatomical Studies on the Spleen and Mesenteric Lymph Node of the Grasscutter

Authors: R. M. Korzerzer, J. O. Hambolu, S. O. Salami, S. B. Oladele

Abstract:

The grasscutter (Thryonomys swinderianus) has become an important source of protein and income to rural dwellers in most West African countries including Nigeria. Twelve apparently healthy grasscutters consisting of six males and six females between the ages of three and seven months were obtained from rural dwellers in Benue state and used for this study. The animals were transported by means of constructed cages to the Department of Veterinary Anatomy, Ahmadu Bello University, Zaria and sacrificed using chloroform inhalation gaseous anaesthesia by suffocation. The spleen and mesenteric lymph nodes were extirpated and the tissues prepared using standard methods, haematoxilin and eosin stain was used for routine histology, while Rhodamine B-aniline-methylene blue stain was used for staining reticular and elastic fibres. The spleen was dark red in colour and roughly triangular in outline, and was observed to increase consistently with age, maximum values were recorded at seven months of age in both males and females. Mean ± SEM values for splenic weights were 0.67 ± 0.09 g, 1.65 ± 0.35 g and 2.31 ± 0.06 g at three, five and seven months of age, respectively. The percentage ratio of splenic weight to body weight was 0.1%. Histologically, the germinal centres revealed three zones; the germinal centre, cortical layer and the marginal zone. The mesenteric lymph nodes were constantly bean shaped and appeared as opaque white masses which resemble fat but were distinguished from fat by their pearly glossy nature. The mean ± SEM values for mesenteric lymph node weights were 0.056 ± 0.005 g, 0.143 ± 0.034 g and 0.1600 ± 0.023 g at three, five and seven months of age, respectively.

Keywords: anatomical, spleen, mesenteric lymph node, grasscutter

Procedia PDF Downloads 569
7386 Comparison of Classical and Ultrasound-Assisted Extractions of Hyphaene thebaica Fruit and Evaluation of Its Extract as Antibacterial Activity in Reducing Severity of Erwinia carotovora

Authors: Hanan Moawad, Naglaa M. Abd EL-Rahman

Abstract:

Erwinia carotovora var. carotovora is the main cause of soft rot in potatoes. Hyphaene thebaica was studied for biocontrol of E. carotovora which inhibited growth of E. carotovora on solid medium, a comparative study of classical and ultrasound-assisted extractions of Hyphaene thebaica fruit. The use of ultrasound decreased significant the total time of treatment and increase the total amount of crude extract. The crude extract was subjected to determine the in vitro, by a bioassay technique revealed that the treatment of paper disks with ultrasound extraction of Hyphaene thebaica reduced the growth of pathogen and produced inhibition zones up to 38mm in diameter. The antioxidant activity of ultrasound-ethanolic extract of Doum fruits (Hyphaene thebaica) was determined. Data obtained showed that the extract contains the secondary metabolites such as Tannins, Saponin, Flavonoids, Phenols, Steroids, Terpenoids, Glycosides and Alkaloids.

Keywords: ultrasound, classical extract, biological control, Erwinia carotovora, Hyphaene thebaica

Procedia PDF Downloads 506
7385 Impact of Fly Ash on Soil Quality in Semi-Arid Region

Authors: Anjuri Srivastava, Akhouri Nishant Bhanu

Abstract:

Soil is a natural material with a distinctive form. It is regarded to be a natural source of nutrients and minerals for plants. It meets many of our needs through the crops, trees, and inhabited places that have grown on or underneath it. Productive and rich soil plays a crucial role in both its wealth and well-being. If any external substance changes the soil's composition, it directly impacts the plant that was grown in that soil. If the soil is deficient in one or more essential components, fly ash can be utilized as fertilizer by incorporating it into the soil. This can also increase the porosity of the soil. Fly ash has a sufficient concentration of essential components to promote the growth of plants. The high concentration of elements in fly ash, including C, Na, K, Fe, and Zn, increases crop yields. Hazardous compounds harm plant life as soon as they get into the soil. The US Environmental Protection Agency and other regulatory agencies have found it as non-hazardous. By employing fly ash as a potential fertilizer supplement for degraded soils, the problem of disposing of solid waste can be partially handled. Fly ash's rapid growth can slow down mineralization because it contains a higher proportion of harmful heavy metals. The chemical characteristics, inclusion ratio, and composting process of fly ash have a significant impact on the fly ash compost’s potential to improve soil nutrition. Research institutions and regulatory agencies have been thoroughly investigating fly ash for a long time. Guard cells on plant leaves that accumulate fly ash trigger the regulatory system. Fly ash increases both chemical and physical damage at certain humidity levels. The lengthy sowing period is caused by the high levels of fly ash in the soil, which also slows down seedling germination and growth. For the sake of human health, it is crucial to consider the bioaccumulation of dangerous heavy metals and their necessary concentrations in plant tissues and soil.

Keywords: soil, fly ash, plant, fertilizer, composts

Procedia PDF Downloads 77
7384 Effect of Total Body Irradiation for Metastatic Lymph Node and Lung Metastasis in Early Stage

Authors: Shouta Sora, Shizuki Kuriu, Radhika Mishra, Ariunbuyan Sukhbaatar, Maya Sakamoto, Shiro Mori, Tetsuya Kodama

Abstract:

Lymph node (LN) metastasis accounts for 20 - 30 % of all deaths in patients with head and neck cancer. Therefore, the control of metastatic lymph nodes (MLNs) is necessary to improve the life prognosis of patients with cancer. In a classical metastatic theory, tumor cells are thought to metastasize hematogenously through a bead-like network of lymph nodes. Recently, a lymph node-mediated hematogenous metastasis theory has been proposed, in which sentinel LNs are regarded as a source of distant metastasis. Therefore, the treatment of MLNs at the early stage is essential to prevent distant metastasis. Radiation therapy is one of the primary therapeutic modalities in cancer treatment. In addition, total body irradiation (TBI) has been reported to act as activation of natural killer cells and increase of infiltration of CD4+ T-cells to tumor tissues. However, the treatment effect of TBI for MLNs remains unclear. This study evaluated the possibilities of low-dose total body irradiation (L-TBI) and middle-dose total body irradiation (M-TBI) for the treatment of MLNs. Mouse breast cancer FM3A-Luc cells were injected into subiliac lymph node (SiLN) of MXH10/Mo/LPR mice to induce the metastasis to the proper axillary lymph node (PALN) and lung. Mice were irradiated for the whole body on 4 days after tumor injection. The L-TBI and M-TBI were defined as irradiations to the whole body at 0.2 Gy and 1.0 Gy, respectively. Tumor growth was evaluated by in vivo bioluminescence imaging system. In the non-irradiated group, tumor activities on SiLN and PALN significantly increased over time, and the metastasis to the lung from LNs was confirmed 28 days after tumor injection. The L-TBI led to a tumor growth delay in PALN but did not control tumor growth in SiLN and metastasis to the lung. In contrast, it was found that the M-TBI significantly delayed the tumor growth of both SiLN and PALN and controlled the distant metastasis to the lung compared with non-irradiated and L-TBI groups. These results suggest that the M-TBI is an effective treatment method for MLNs in the early stage and distant metastasis from lymph nodes via blood vessels connected with LNs.

Keywords: metastatic lymph node, lung metastasis, radiation therapy, total body irradiation, lymphatic system

Procedia PDF Downloads 167
7383 Edmonton Urban Growth Model as a Support Tool for the City Plan Growth Scenarios Development

Authors: Sinisa J. Vukicevic

Abstract:

Edmonton is currently one of the youngest North American cities and has achieved significant growth over the past 40 years. Strong urban shift requires a new approach to how the city is envisioned, planned, and built. This approach is evidence-based scenario development, and an urban growth model was a key support tool in framing Edmonton development strategies, developing urban policies, and assessing policy implications. The urban growth model has been developed using the Metronamica software platform. The Metronamica land use model evaluated the dynamic of land use change under the influence of key development drivers (population and employment), zoning, land suitability, and land and activity accessibility. The model was designed following the Big City Moves ideas: become greener as we grow, develop a rebuildable city, ignite a community of communities, foster a healing city, and create a city of convergence. The Big City Moves were converted to three development scenarios: ‘Strong Central City’, ‘Node City’, and ‘Corridor City’. Each scenario has a narrative story that expressed scenario’s high level goal, scenario’s approach to residential and commercial activities, to transportation vision, and employment and environmental principles. Land use demand was calculated for each scenario according to specific density targets. Spatial policies were analyzed according to their level of importance within the policy set definition for the specific scenario, but also through the policy measures. The model was calibrated on the way to reproduce known historical land use pattern. For the calibration, we used 2006 and 2011 land use data. The validation is done independently, which means we used the data we did not use for the calibration. The model was validated with 2016 data. In general, the modeling process contain three main phases: ‘from qualitative storyline to quantitative modelling’, ‘model development and model run’, and ‘from quantitative modelling to qualitative storyline’. The model also incorporates five spatial indicators: distance from residential to work, distance from residential to recreation, distance to river valley, urban expansion and habitat fragmentation. The major finding of this research could be looked at from two perspectives: the planning perspective and technology perspective. The planning perspective evaluates the model as a tool for scenario development. Using the model, we explored the land use dynamic that is influenced by a different set of policies. The model enables a direct comparison between the three scenarios. We explored the similarities and differences of scenarios and their quantitative indicators: land use change, population change (and spatial allocation), job allocation, density (population, employment, and dwelling unit), habitat connectivity, proximity to objects of interest, etc. From the technology perspective, the model showed one very important characteristic: the model flexibility. The direction for policy testing changed many times during the consultation process and model flexibility in applying all these changes was highly appreciated. The model satisfied our needs as scenario development and evaluation tool, but also as a communication tool during the consultation process.

Keywords: urban growth model, scenario development, spatial indicators, Metronamica

Procedia PDF Downloads 80
7382 Effect of Specimen Thickness on Probability Distribution of Grown Crack Size in Magnesium Alloys

Authors: Seon Soon Choi

Abstract:

The fatigue crack growth is stochastic because of the fatigue behavior having an uncertainty and a randomness. Therefore, it is necessary to determine the probability distribution of a grown crack size at a specific fatigue crack propagation life for maintenance of structure as well as reliability estimation. The essential purpose of this study is to present the good probability distribution fit for the grown crack size at a specified fatigue life in a rolled magnesium alloy under different specimen thickness conditions. Fatigue crack propagation experiments are carried out in laboratory air under three conditions of specimen thickness using AZ31 to investigate a stochastic crack growth behavior. The goodness-of-fit test for probability distribution of a grown crack size under different specimen thickness conditions is performed by Anderson-Darling test. The effect of a specimen thickness on variability of a grown crack size is also investigated.

Keywords: crack size, fatigue crack propagation, magnesium alloys, probability distribution, specimen thickness

Procedia PDF Downloads 484
7381 Assessment of Waste Management Practices in Bahrain

Authors: T. Radu, R. Sreenivas, H. Albuflasa, A. Mustafa Khan, W. Aloqab

Abstract:

The Kingdom of Bahrain, a small island country in the Gulf region, is experiencing fast economic growth resulting in a sharp increase in population and greater than ever amounts of waste being produced. However, waste management in the country is still very basic, with landfilling being the most popular option. Recycling is still a scarce practice, with small recycling businesses and initiatives emerging in recent years. This scenario is typical for other countries in the region, with similar amounts of per capita waste being produced. In this paper, we are reviewing current waste management practices in Bahrain by collecting data published by the Government and various authors, and by visiting the country’s only landfill site, Askar. In addition, we have performed a survey of the residents to learn more about the awareness and attitudes towards sustainable waste management strategies. A review of the available data on waste management indicates that the Askar landfill site is nearing its capacity. The site uses open tipping as the method of disposal. The highest percentage of disposed waste comes from the building sector (38.4%), followed by domestic (27.5%) and commercial waste (17.9%). Disposal monitoring and recording are often based on estimates of weight and without proper characterization/classification of received waste. Besides, there is a need for assessment of the environmental impact of the site with systematic monitoring of pollutants in the area and their potential spreading to the surrounding land, groundwater, and air. The results of the survey indicate low awareness of what happens with the collected waste in the country. However, the respondents have shown support for future waste reduction and recycling initiatives. This implies that the education of local communities would be very beneficial for such governmental initiatives, securing greater participation. Raising awareness of issues surrounding recycling and waste management and systematic effort to divert waste from landfills are the first steps towards securing sustainable waste management in the Kingdom of Bahrain.

Keywords: landfill, municipal solid waste, survey, waste management

Procedia PDF Downloads 142
7380 Investigating the Environmental Impact of Additive Manufacturing Compared to Conventional Manufacturing through Life Cycle Assessment

Authors: Gustavo Menezes De Souza Melo, Arnaud Heitz, Johannes Henrich Schleifenbaum

Abstract:

Additive manufacturing is a growing market that is taking over in many industries as it offers numerous advantages like new design possibilities, weight-saving solutions, ease of manufacture, and simplification of assemblies. These are all unquestionable technical or financial assets. As to the environmental aspect, additive manufacturing is often discussed whether it is the best solution to decarbonize our industries or if conventional manufacturing remains cleaner. This work presents a life cycle assessment (LCA) comparison based on the technological case of a motorbike swing-arm. We compare the original equipment manufacturer part made with conventional manufacturing (CM) methods to an additive manufacturing (AM) version printed using the laser powder bed fusion process. The AM version has been modified and optimized to achieve better dynamic performance without any regard to weight saving. Lightweight not being a priority in the creation of the 3D printed part brings us a unique perspective in this study. To achieve the LCA, we are using the open-source life cycle, and sustainability software OpenLCA combined with the ReCiPe 2016 at midpoint and endpoint level method. This allows the calculation and the presentation of the results through indicators such as global warming, water use, resource scarcity, etc. The results are then showing the relative impact of the AM version compared to the CM one and give us a key to understand and answer questions about the environmental sustainability of additive manufacturing.

Keywords: additive manufacturing, environmental impact, life cycle assessment, laser powder bed fusion

Procedia PDF Downloads 242
7379 Expanded Access through Open and Distance Learning in Nigeria

Authors: Okoro Ngozi Priscilla

Abstract:

Education is the bedrock of development in every nation of the world, and it is very useful in ensuring quality of life for every individual and a better world for the people. Education, therefore, is the basic instrument of economic growth and technological advancement in any society. It is in recognition of this fact that the Nigerian government commits immense resources to ensuring that its citizens acquire education and also policies are being made to ensure the accessibility of education, qualitative higher education is highly recognized as a vital driving force for the socio-economic growth and technological development of nations yet the problem of access to University education in the country persists and therefore brought about the introduction of Open and Distance Learning (ODL) which has as its main objective, the attainment of mass literacy and providing opportunities for those who could not gain admission through designated entrance examination agencies as well as those who could not afford to leave their job to attend a full-time educational programme. Open and distance learning seeks to improve skilled manpower and also improve the skills for those already at work.

Keywords: accessibility, open and distant learning programme, fulltime educational programme, distance learning

Procedia PDF Downloads 442
7378 Cytotoxic Activity against MCF-7 Breast Cancer Cells and Antioxidant Property of Aqueous Tempe Extracts from Extended Fermentation

Authors: Zatil Athaillah, Anastasia Devi, Dian Muzdalifah, Wirasuwasti Nugrahani, Linar Udin

Abstract:

During tempe fermentation, some chemical changes occurred and they contributed to sensory, appearance, and health benefits of soybeans. Many studies on health properties of tempe have specialized on their isoflavones. In this study, other components of tempe, particularly water soluble chemicals, was investigated for their biofunctionality. The study was focused on the ability to suppress MCF-7 breast cancer cell growth and antioxidant activity, as expressed by DPPH radical scavenging activity, total phenols and total flavonoids, of the water extracts. Fermentation time of tempe was extended up to 120 hr to increase the possibility to find the functional components. Extraction yield and soluble nitrogen content were also quantified as accompanying data. Our findings suggested that yield of water extraction of tempe increased as fermentation was extended up to 120 hr, except for a slight decrease at 72 hr. Water extracts of tempe showed inhibition of MCF-7 breast cancer cell growth, as shown by lower IC50 values when compared to control (unfermented soybeans). Among the varied fermentation timescales, 60-hr period showed the highest activity (IC50 of 8.7 ± 4.95 µg/ml). The anticancer activity of extracts obtained from different fermentation time was positively correlated with total soluble nitrogens, but less relevant with antioxidant data. During 48-72 hr fermentation, at which cancer suppression activity was significant, the antioxidant properties from the three assays were not higher than control. These findings indicated that water extracts of tempe from extended fermentation could inhibit breast cancer cell growth but further study to determine the mechanism and compounds that play important role in the activity should be conducted.

Keywords: tempe, anticancer, antioxidant, phenolic compounds

Procedia PDF Downloads 231
7377 Some Factors Affecting Reproductive Traits in Nigerian Indigenous Chickens under Intensive Management System

Authors: J. Aliyu, A. O. Raji, A. A. Ibrahim

Abstract:

The study was carried out to assess the fertility, early and late embryonic mortalities as well as hatchability by strain, season and hen’s weight in Nigerian indigenous chickens reared on deep litter. Four strains (normal feathered, naked neck, frizzle and dwarf) of hens maintained at a mating ratio of 1 cock to 4 hens, fed breeders mash and water ad libitum were used in a three year experiment. The data generated were subjected to analysis of variance using the SAS package and the means, where significant, were separated using the least significant difference (LSD). There were significant effects (P < 0.05) of strain on all the traits studied. Fertility was generally high (84.29 %) in all the strains. Early embryonic mortality was significantly lowest (P < 0.01) in naked neck which had the highest late embryonic mortality (P < 0.001). Hatchability was significantly highest (P < 0.01) in normal feathered (80.23 %) and slightly depressed in frizzle (74.95 %) and dwarf (72.27 %) while naked neck had the lowest (60.80 %). Season of the year had significant effects on early embryonic mortality. Dry hot season significantly (P < 0.05) depressed fertility while early embryonic mortality was depressed in the wet season (15.33 %). Early and late embryonic mortalities significantly increased (P < 0.05) with increasing weight of hen. Dwarf, frizzle and normal feathered hens could be used to improve hatchability as well as reduce early and late embryonic mortalities in Nigerian indigenous chickens.

Keywords: chicken, fertility, hatchability, indigenous, strain

Procedia PDF Downloads 403