Search results for: water repellent
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8698

Search results for: water repellent

1708 Functionalized Magnetic Iron Oxide Nanoparticles for Extraction of Protein and Metal Nanoparticles from Complex Fluids

Authors: Meenakshi Verma, Mandeep Singh Bakshi, Kultar Singh

Abstract:

Magnetic nanoparticles have received incredible importance in view of their diverse applications, which arise primarily due to their response to the external magnetic field. The magnetic behaviour of magnetic nanoparticles (NPs) helps them in numerous different ways. The most important amongst them is the ease with which they can be purified and also can be separated from the media in which they are present merely by applying an external magnetic field. This exceptional ease of separation of the magnetic NPs from an aqueous media enables them to use for extracting/removing metal pollutants from complex aqueous medium. Functionalized magnetic NPs can be subjected for the metallic impurities extraction if are favourably adsorbed on the NPs surfaces. We have successfully used the magnetic NPs as vehicles for gold and silver NPs removal from the complex fluids. The NPs loaded with gold and silver NPs pollutant fractions has been easily removed from the aqueous media by using external magnetic field. Similarly, we have used the magnetic NPs for extraction of protein from complex media and then constantly washed with pure water to eliminate the unwanted surface adsorbed components for quantitative estimation. The purified and protein loaded magnetic NPs are best analyzed with SDS Page to not only for characterization but also for separating the protein fractions. A collective review of the results indicates that we have synthesized surfactant coated iron oxide NPs and then functionalized these with selected materials. These surface active magnetic NPs work very well for the extraction of metallic NPs from the aqueous bulk and make the whole process environmentally sustainable. Also, magnetic NPs-Au/Ag/Pd hybrids have excellent protein extracting properties. They are much easier to use in order to extract the magnetic impurities as well as protein fractions under the effect of external magnetic field without any complex conventional purification methods.

Keywords: magnetic nanoparticles, protein, functionalized, extraction

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1707 Free Raducal Scavenging Activity of Fractionated Extract and Structural Elucidation of Isolated Compounds from Hydrocotyl Bonariensis Comm. Ex Lam Leaves

Authors: Emmanuel O Ajani, Sabiu S, Mariam Zakari, Fisayo A Bamisaye

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Hydrocotyl bonariensis is a plant which anticataractogenic potentials have been reported. In the present study an attempt was made to evaluate the in vitro antioxidant activity of the fractionates of the leaves extract and also characterize some of its chemical constituents. DPPH, H₂O₂, OH and NO free radical scavenging, metal chelating and reducing power activity was used to evaluate the antioxidant activity of the crude extract fractionates. Fresh leaves of Hydrocotyl bonariensis leaves were extracted in 70% methanol. The extract was partitioned with different solvent system of increasing polarity (n-hexane, chloroform, ethyl acetate methanol and water). Compounds were isolated from the aqueous practitionate using accelerated gradient chromatography, vacuum liquid chromatography, preparative TLC and conventional column chromatography. The presence of the chemical groups was established with HPLC and Fourier Transform Infra Red. The structures of isolated compounds were elucidated by spectroscopic study and chemical shifts. Data from the study indicates that all the fractionates contain compounds with free radical scavenging activity. This activity was more pronounced in the aqueous fractionate (DPPH IC₅₀, 0025 ± 0.011 mg/ml, metal chelating capacity 27.5%, OH- scavenging IC₅₀, 0.846 ± 0.037 mg/ml, H₂O₂ scavenging IC₅₀ 0.521 ± 0.015 mg/ml, reducing power IC₅₀ 0.248 ± 0.025 mg/ml and NO scavenging IC₅₀ 0.537 ± 0.038 mg/ml). Two compounds were isolated and when compared with data from the literature; the structures were suggestive of polyphenolic flavonoid, quercetin and 3-O-β-D-glucopyranosyl-sitosterol. The result indicates that H. bonariensis leaves contain bioactive compounds with antioxidant activity.

Keywords: antioxidant, cataract, free radical, flavonoids, hydrocotyl bonariensis

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1706 Influence of Salicylic Acid on Submergence Stress Recovery in Selected Rice Cultivars (Oryza sativa L.)

Authors: Ja’afar U., A. M. Gumi, Salisu N., Obadiah C. D.

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Rice is susceptible to flooding due to its semi-aquatic characteristics, which enable it to thrive in wet or submerged environments. The development of aerenchyma allows for oxygen transfer, enabling faster lengthening of submerged shoot organs. Rice's germination and early seedling growth phases are highly intolerant of submersion, resulting in survival in low-oxygen environments. The research involved a study on rice plants treated with salicylic acid at different concentrations. Hypo was used for washing, while a reagent was used for submergence treatment. The plants were waterlogged for 11 days and submerged for 7 days, with control plants receiving distilled water. The study found a significant difference between Jirani Zawara's control and treated plants, with plants treated with 2 g/L of S.A. showing a 6.00 node increase per plant and Faro cultivars having more nodes. The study found significant differences between the control and treated plants, with the Jirani Zawara plant showing longer internode lengths and the Faro cultivar having longer internode lengths, while the B.G. cultivar had the longest. The research found that the Jirani Zawara cultivar treated with 3 g/L of S.A. produced tallest plants, with heights increasing from 14.43 cm to 15.50 cm in Faro cultivar S.A., and the highest height was 16.30 cm. The study reveals that salicylic acid significantly enhances the number of nodes, internode length, plant height, and root length in rice cultivars, thereby improving submerged stress recovery and promoting plant development.

Keywords: rice, submergence, stress, salicylic acid

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1705 Review of Downscaling Methods in Climate Change and Their Role in Hydrological Studies

Authors: Nishi Bhuvandas, P. V. Timbadiya, P. L. Patel, P. D. Porey

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Recent perceived climate variability raises concerns with unprecedented hydrological phenomena and extremes. Distribution and circulation of the waters of the Earth become increasingly difficult to determine because of additional uncertainty related to anthropogenic emissions. According to the sixth Intergovernmental Panel on Climate Change (IPCC) Technical Paper on Climate Change and water, changes in the large-scale hydrological cycle have been related to an increase in the observed temperature over several decades. Although many previous research carried on effect of change in climate on hydrology provides a general picture of possible hydrological global change, new tools and frameworks for modelling hydrological series with nonstationary characteristics at finer scales, are required for assessing climate change impacts. Of the downscaling techniques, dynamic downscaling is usually based on the use of Regional Climate Models (RCMs), which generate finer resolution output based on atmospheric physics over a region using General Circulation Model (GCM) fields as boundary conditions. However, RCMs are not expected to capture the observed spatial precipitation extremes at a fine cell scale or at a basin scale. Statistical downscaling derives a statistical or empirical relationship between the variables simulated by the GCMs, called predictors, and station-scale hydrologic variables, called predictands. The main focus of the paper is on the need for using statistical downscaling techniques for projection of local hydrometeorological variables under climate change scenarios. The projections can be then served as a means of input source to various hydrologic models to obtain streamflow, evapotranspiration, soil moisture and other hydrological variables of interest.

Keywords: climate change, downscaling, GCM, RCM

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1704 Assessment of the Physicochemical Qualities and Prevalence of Vibrio Pathogens in the Final Effluents of Two Wastewater Treatment Plants in Eastern Cape Province, South Africa

Authors: C. A Osunla, A. I. Okoh

Abstract:

Treated wastewater effluent has been found to encompass high levels of pollutants, including disease-causing bacteria such as Vibrio pathogens. The current study was designed to evaluate the physicochemical qualities and prevalence of Vibrio pathogens in treated effluents of two wastewater treatment plants (WWTP) in Eastern Cape Province, South Africa over the period of six months. Parameters measured include pH, temperature, electrical conductivity, salinity, turbidity, total dissolved solid (TDS), dissolved oxygen (DO), and free chlorine; and these parameters were simultaneously monitored in the treated final effluents of the two wastewater treatment plants using standard methods. The ranges of values for the physicochemical are: pH (7.0–8.6), total dissolved solids (286.3–916.5 mg/L), electrical conductivity (572.57–1704.5 mS/m), temperature (10.3–28.6 °C), turbidity (4.02–43.20 NTU), free chlorine (0.00–0.19 mg/L), dissolve oxygen (2.06–6.32 mg/L) and biochemical oxygen demand (0.1–9.0 mg/L). The microbiological assessment for both WWTPs revealed the presence of Vibrio counts ranging between 0 and 8.76×104 CFU/100 mL. The obtained values of the measured parameters and Vibrio loads of the treated wastewater effluents were found outside the compliance levels of the South African guidelines and World Health Organization tolerance limits for effluents intended to be discharged into receiving waterbodies. Hence, we conclude that these WWTPs are important point sources of pollution in surface water with potential public health and ecological risks.

Keywords: effluents, public health, South Africa, Vibrio, wastewater

Procedia PDF Downloads 360
1703 Application and Limitation of Heavy Metal Pollution Indicators in Coastal Environment of Pakistan

Authors: Noor Us Saher

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Oceans and Marine areas have a great importance, mainly regarding food resources, fishery products and reliance of livelihood. Aquatic pollution is common due to the incorporation of various chemicals mainly entering from urbanization, industrial and commercial facilities, such as oil and chemical spills. Many hazardous wastes and industrial effluents contaminate the nearby areas and initiate to affect the marine environment. These contaminated conditions may become worse in those aquatic environments situated besides the world’s largest cities, which are hubs of various commercial activities. Heavy metal contamination is one of the most important predicaments for marine environments and during past decades this problem has intensified due to an increase in urbanization and industrialization. Coastal regions of Pakistan are facing severe threats from various organic and inorganic pollutants, especially the estuarine and coastal areas of Karachi city, the most populated and industrialized city situated along the coastline. Metal contamination causes severe toxicity in biota resulting the degradation of Marine environments and depletion of fishery resources and sustainability. There are several abiotic (air, water and sediment) and biotic (fauna and flora) indicators that indicate metal contamination. However, all these indicators have certain limitations and complexities, which delay their implementation for rehabilitation and conservation in the marine environment. The inadequate evidences have presented on this significant topic till the time and this study discussed metal pollution and its consequences along the marine environment of Pakistan. This study further helps in identification of possible hazards for the ecological system and allied resources for management strategies and decision making for sustainable approaches.

Keywords: coastal and estuarine environment, heavy metals pollution, pollution indicators, Pakistan

Procedia PDF Downloads 253
1702 Comparative Parametric and Emission Characteristics of Single Cylinder Spark Ignition Engine Using Gasoline, Ethanol, and H₂O as Micro Emulsion Fuels

Authors: Ufaith Qadri, M Marouf Wani

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In this paper, the performance and emission characteristics of a Single Cylinder Spark Ignition engine have been investigated. The research is based on micro emulsion application as fuel in a gasoline engine. We have analyzed many micro emulsion compositions in various proportions, for predicting the performance of the Spark Ignition engine. This new technology of fuel modifications is emerging very rapidly as lot of research is going on in the field of micro emulsion fuels in Compression Ignition engines, but the micro emulsion fuel used in a Gasoline engine is very rare. The use of micro emulsion as fuel in a Spark Ignition engine is virtually unexplored. So, our main goal is to see the performance and emission characteristics of micro emulsions as fuel, in Spark Ignition engines, and finding which composition is more efficient. In this research, we have used various micro emulsion fuels whose composition varies for all the three blends, and their performance and emission characteristic were predicted in AVL Boost software. Conventional Gasoline fuel 90%, 80% and 85% were blended with co-surfactant Ethanol in different compositions, and water was used as an additive for making it crystal clear transparent micro emulsion fuel, which is thermodynamically stable. By comparing the performances of engines, the power has shown similarity for micro emulsion fuel and conventional Gasoline fuel. On the other hand, Torque and BMEP shows increase for all the micro emulsion fuels. Micro emulsion fuel shows higher thermal efficiency and lower Specific Fuel Consumption for all the compositions as compared to the Gasoline fuel. Carbon monoxide and Hydro carbon emissions were also measured. The result shows that emissions decrease for all the composition of micro emulsion fuels, and proved to be the most efficient fuel both in terms of performance and emission characteristics.

Keywords: AVL Boost, emissions, microemulsions, performance, Spark Ignition (SI) engine

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1701 Innovative Waste Management Practices in Remote Areas

Authors: Dolores Hidalgo, Jesús M. Martín-Marroquín, Francisco Corona

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Municipal waste consist of a variety of items that are everyday discarded by the population. They are usually collected by municipalities and include waste generated by households, commercial activities (local shops) and public buildings. The composition of municipal waste varies greatly from place to place, being mostly related to levels and patterns of consumption, rates of urbanization, lifestyles, and local or national waste management practices. Each year, a huge amount of resources is consumed in the EU, and according to that, also a huge amount of waste is produced. The environmental problems derived from the management and processing of these waste streams are well known, and include impacts on land, water and air. The situation in remote areas is even worst. Difficult access when climatic conditions are adverse, remoteness of centralized municipal treatment systems or dispersion of the population, are all factors that make remote areas a real municipal waste treatment challenge. Furthermore, the scope of the problem increases significantly because the total lack of awareness of the existing risks in this area together with the poor implementation of advanced culture on waste minimization and recycling responsibly. The aim of this work is to analyze the existing situation in remote areas in reference to the production of municipal waste and evaluate the efficiency of different management alternatives. Ideas for improving waste management in remote areas include, for example: the implementation of self-management systems for the organic fraction; establish door-to-door collection models; promote small-scale treatment facilities or adjust the rates of waste generation thereof.

Keywords: door to door collection, islands, isolated areas, municipal waste, remote areas, rural communities

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1700 The Impact of Liquid Glass-Infused Lignin Waste Particles on Performance of Polyurethane Foam for Building Industry

Authors: Agnė Kairyte, Saulius Vaitkus

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The gradual depletion of fossil feedstock and growing environmental concerns attracted extensive attention to natural resources due to their low cost, high abundance, renewability, sustainability, and biodegradability. Lignin is a significant by-product of the pulp and paper industry, having unique functional groups. Recently it became interesting for the manufacturing of high value-added products such as polyurethane and polyisocyanurate foams. This study focuses on the development of high-performance polyurethane foams with various amounts of lignin as a filler. It is determined that the incorporation of lignin as a filler material results in brittle and hard products due to the low molecular mobility of isocyanates and the inherent stiffness of lignin. Therefore, the current study analyses new techniques and possibilities of liquid glass infusion onto the surface of lignin particles to reduce the negative aspects and improve the performance characteristics of the modified foams. The foams modified with sole lignin and liquid glass-infused lignin had an apparent density ranging from 35 kg/m3 to 45 kg/m3 and closed-cell content (80–90%). The incorporation of sole lignin reduced the compressive and tensile strengths and increased dimensional stability and water absorption, while the contrary results were observed for polyurethane foams with liquid glass-infused lignin particles. The effect on rheological parameters of lignin and liquid glass infused lignin modified polyurethane premixes and morphology of polyurethane foam products were monitored to optimize the conditions and reveal the significant influence of the interaction between particles and polymer matrix.

Keywords: filler, lignin waste, liquid glass, polymer matrix, polyurethane foam, sustainability

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1699 Investigation on Remote Sense Surface Latent Heat Temperature Associated with Pre-Seismic Activities in Indian Region

Authors: Vijay S. Katta, Vinod Kushwah, Rudraksh Tiwari, Mulayam Singh Gaur, Priti Dimri, Ashok Kumar Sharma

Abstract:

The formation process of seismic activities because of abrupt slip on faults, tectonic plate moments due to accumulated stress in the Earth’s crust. The prediction of seismic activity is a very challenging task. We have studied the changes in surface latent heat temperatures which are observed prior to significant earthquakes have been investigated and could be considered for short term earthquake prediction. We analyzed the surface latent heat temperature (SLHT) variation for inland earthquakes occurred in Chamba, Himachal Pradesh (32.5 N, 76.1E, M-4.5, depth-5km) nearby the main boundary fault region, the data of SLHT have been taken from National Center for Environmental Prediction (NCEP). In this analysis, we have calculated daily variations with surface latent heat temperature (0C) in the range area 1⁰x1⁰ (~120/KM²) with the pixel covering epicenter of earthquake at the center for a three months period prior to and after the seismic activities. The mean value during that period has been considered in order to take account of the seasonal effect. The monthly mean has been subtracted from daily value to study anomalous behavior (∆SLHT) of SLHT during the earthquakes. The results found that the SLHTs adjacent the epicenters all are anomalous high value 3-5 days before the seismic activities. The abundant surface water and groundwater in the epicenter and its adjacent region can provide the necessary condition for the change of SLHT. To further confirm the reliability of SLHT anomaly, it is necessary to explore its physical mechanism in depth by more earthquakes cases.

Keywords: surface latent heat temperature, satellite data, earthquake, magnetic storm

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1698 Egg Hatching Inhibition Activity of Volatile Oils Extracted from Some Medicinal and Aromatic Plants against Root-Knot Nematode Meloidogyne hapla

Authors: Anil F. Felek, Mehmet M. Ozcan, Faruk Akyazi

Abstract:

Volatile oils of medicinal and aromatic plants are important for managing nematological problems in agriculture. In present study, volatile oils extracted from five medicinal and aromatic plants including Origanum onites (flower+steam+leaf), Salvia officinalis (leaf), Lippia citriodora (leaf+seed), Mentha spicata (leaf) and Mentha longifolia (leaf) were tested for egg hatching inhibition activity against root-knot nematode Meloidogyne hapla under laboratory conditions. The essential oils were extracted using water distillation method with a Clevenger system. For the homogenisation process of the oils, 2% gum arabic solution was used and 4 µl oils was added into 1ml filtered gum arabic solution to prepare the last stock solution. 5 ml of stock solution and 1 ml of M. hapla egg suspension (about 100 eggs) were added into petri dishes. Gum arabic solution was used as control. Seven days after exposure to oils at room temperature (26±2 °C), the cumulative hatched and unhatched eggs were counted under 40X inverted light microscope and Abbott’s formula was used to calculate egg hatching inhibition rates. As a result, the highest inhibition rate was found as 54% for O. onites. In addition, the other inhibition rates varied as 31.4%, 21.6%, 23.8%, 25.67% for the other plants, S. officinalis, M. longifolia, M. spicata and L. citriodora, respectively. Carvacrol was found as the main component (68.8%) of O. onites followed by Thujone 27.77% for S. officinalis, I-Menthone 76.92% for M. longifolia, Carvone 27.05% for M. spicata and Citral 19.32% for L. citriodora.

Keywords: egg hatching, Meloidogyne hapla, medicinal and aromatic plants, root-knot nematodes, volatile oils

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1697 Use of Non-woven Polyethylene Terephthalate Fabrics to Improve Certain Properties of Concrete

Authors: Sifatullah Bahij, Safiullah Omary, Francoise Feugeas, Amanullah Faqiri

Abstract:

Plastic packages have been broadly used for a long time. Such widespread usage of plastic has resulted in an increased amount of plastic wastes and many environmental impacts. Plastic wastes are one of the most significant types of waste materials because of their non-degradation and low biodegradability. It is why many researchers tried to find a safe and environmentally friendly solution for plastic wastes. In this goal, in the civil engineering industry, many types of plastic wastes have been incorporated, as a partial substitution of aggregates or as additive materials (fibers) in concrete mixtures because of their lengthier lifetime and lower weight. This work aims to study the mechanical properties (compressive, split tensile and flexural strengths) of concrete with a water-cement ratio (w/c) of 0.45 and with the incorporation of non-woven PET plastic sheets. Five configurations -without PET (reference), 1-layer sheet, 2-side, 3-side, and full sample wrapping- were applied. The 7, 14 and 28-days samples’ compressive strengths, flexural strength and split tensile strength were measured. The outcomes of the study show that the compressive strength was improved for the wrapped samples, particularly for the cylindrical specimens. Also, split tensile and flexural behaviors of the wrapped samples improved significantly compared to the reference ones. Moreover, reference samples were damaged into many parts after mechanical testing, while wrapped specimens were taken by the applied configurations and were not divided into many small fragments. Therefore, non-woven fabrics appeared to improve some properties of the concrete.

Keywords: solid waste plastic, non-woven polyethylene terephthalate sheets, mechanical behaviors, crack pattern

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1696 Perspective for the Creation of Molecular Imprinted Polymers from Coal Waste

Authors: Alma Khasenovna Zhakina, Arnt Oxana Vasilievna, Vasilets Evgeny Petrovich

Abstract:

The aim of this project is to develop methods for obtaining new molecularly imprinted polymers from coal waste to study their structure, structural and morphological features and properties. Recently, the development of molecularly imprinted polymers has become one of the hot topics for researchers. Modern research indicates the broad prospects of rapidly developing molecular imprinting technologies for creating a new generation of sorption materials. The attractiveness of this area of research lies in the fact that the use of imprinted polymers is not limited to scientific research; they are already being introduced in the chemical, pharmaceutical and biotechnological industries, primarily at the stages of purification of the final product. For the use of molecularly imprinted polymers in the development of sorption material, their ability to selectively remove pollutants, including trace concentrations, is of fundamental importance, and the exceptional stability of polymeric materials under harsh conditions makes it possible to simplify the process of water purification as a whole. The scientific and technical effect is associated with the development of technologies for the production of new molecularly imprinted polymers, the establishment of optimal conditions for their production and the creation of effective imprinted sorbents on their basis for wastewater treatment from heavy metals. The social effect is due to the fact that the use of coal waste as a feedstock for the production of imprinted sorbents will make it possible in the future to create new industries with additional jobs and obtain competitive multi-purpose products. The economic and multiplier effect is associated with the low cost of the final product due to the involvement of local coal waste in the production, reduction of transport, customs and other costs.

Keywords: imprinted polymers, coal waste, polymerization, template, customized sorbents

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1695 Bacterio-Algal Microbial Fuel Cells for Sustainable Power Production, Wastewater Treatment, and Desalination

Authors: Ann D. Christy, Beenish Saba

Abstract:

The Microbial fuel Cell (MFC) is a successful integrated technology for power production and wastewater treatment. MFCs are recognized for their dual function, but research in this field is still ongoing to increase efficiency and power output. One such effort is successful integration of phototrophic and autotrophic microorganisms to create bacterio-algal MFCs for sustainable electricity production along with wastewater treatment and algal biomass production. An MFC is typically configured with an anaerobic anodic chamber containing exoelectrogenic microorganisms separated by a cation exchange membrane from an adjacent aerobic cathodic chamber. The two electrodes are connected by an external circuit. This conventional MFC can be converted into a phototrophic MFC by introducing photosynthetic microorganisms into the cathode chamber. This study examines adding a third desalination chamber to a two-chamber bacterio-algal MFC. Successful results have been observed from these three-chamber MFCs demonstrating wastewater treatment in the anodic chamber, phototrophic algal growth in the cathodic chamber, and desalination in the middle chamber. The present article will summarize successful results of the bacterio-algal fuel cells and offer insights about the mechanisms involved. Tables summarizing the input substrate along with optimized operational conditions and output performance in terms of power production and efficiencies of water and wastewater treatment will be presented. The negative impacts and challenges will be discussed, along with possible future research directions. Results suggest that the three chamber bacterio-algal desalination cell has potential as a feasible technology for power production, wastewater treatment and desalination, but it needs further investigation under optimized conditions.

Keywords: bacterio-algal MFC, three chamber, microbial fuel cell, wastewater treatment and desalination

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1694 Effect of Shape and Size of Concrete Specimen and Strength of Concrete Mixture in the Absence and Presence of Fiber

Authors: Sultan Husein Bayqra, Ali Mardani Aghabaglou, Zia Ahmad Faqiri, Hassane Amidou Ouedraogo

Abstract:

In this study, the effect of shape and size of the concrete specimen on the compressive and splitting tensile strength of the concrete mixtures in the absence and presence of steel fiber was investigated. For this aim, ten different concrete mixtures having w/c ratio of 0.3, 0.4, 0.5, 0.6 and 0.7 with and without fiber were prepared. In the mixtures containing steel fibers having aspect ratio (L/D) of 64 were used by 1% of the total mixture volume. In all concrete mixtures, CEM I 42,5R type Portland cement and crushed Lime-stone aggregates having different aggregate size fractions were used. The combined aggregate was obtained by mixing %40 0-5 mm, %30 5-12 mm and %30 12-22 mm aggregate size fraction. The slump values of concrete mixtures were kept constant as 17 ± 2 cm. To provide the desired slump value, a polycarboxylate ether-based high range water reducing admixture was used. In order to investigate the effect of size and shape of concrete specimen on strength properties 10 cm, 15 cm cubic specimens and 10×20 cm, 15×30 cm cylindrical specimens were prepared for each mixture. The specimens were cured under standard conditions until testing days. The 7- and 28-day compressive and splitting tensile strengths of mixtures were determined. The results obtained from the experimental study showed that the strength ratio between the cylinder and the cube specimens increased with the increase of the strength of the concrete. Regardless of the fiber utilization and specimen shape, strength values of concrete mixtures were increased by decreasing specimen size. However, the mentioned behaviour was not observed for the case that the mixtures having high W/C ratio and containing fiber. The compressive strength of cube specimens containing fiber was less affected by the size of the specimen compared to that of cube specimens containing no fibers.

Keywords: compressive strength, splitting tensile strength, fiber reinforced concrete, size effect, shape effect

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1693 A Hybrid Energy Storage Module for the Emergency Energy System of the Community Shelter in Yucatán, México

Authors: María Reveles-Miranda, Daniella Pacheco-Catalán

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Sierra Papacal commissary is located north of Merida, Yucatan, México, where the indigenous Maya population predominates. Due to its location, the region has an elevation of fewer than 4.5 meters above sea level, with a high risk of flooding associated with storms and hurricanes and a high vulnerability of infrastructure and housing in the presence of strong gusts of wind. In environmental contingencies, the challenge is providing an autonomous electrical supply using renewable energy sources that cover vulnerable populations' health, food, and water pumping needs. To address this challenge, a hybrid energy storage module is proposed for the emergency photovoltaic (PV) system of the community shelter in Sierra Papacal, Yucatán, which combines high-energy-density batteries and high-power-density supercapacitors (SC) in a single module, providing a quick response to energy demand, reducing the thermal stress on batteries and extending their useful life. Incorporating SC in energy storage modules can provide fast response times to power variations and balanced energy extraction, ensuring a more extended period of electrical supply to vulnerable populations during contingencies. The implemented control strategy increases the module's overall performance by ensuring the optimal use of devices and balanced energy exploitation. The operation of the module with the control algorithm is validated with MATLAB/Simulink® and experimental tests.

Keywords: batteries, community shelter, environmental contingencies, hybrid energy storage, isolated photovoltaic system, supercapacitors

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1692 Evaluating the Impact of Expansion on Urban Thermal Surroundings: A Case Study of Lahore Metropolitan City, Pakistan

Authors: Usman Ahmed Khan

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Urbanization directly affects the existing infrastructure, landscape modification, environmental contamination, and traffic pollution, especially if there is a lack of urban planning. Recently, the rapid urban sprawl has resulted in less developed green areas and has devastating environmental consequences. This study was aimed to study the past urban expansion rates and measure LST from satellite data. The land use land cover (LULC) maps of years 1996, 2010, 2013, and 2017 were generated using landsat satellite images. Four main classes, i.e., water, urban, bare land, and vegetation, were identified using unsupervised classification with iterative self-organizing data analysis (isodata) technique. The LST from satellite thermal data can be derived from different procedures: atmospheric, radiometric calibrations and surface emissivity corrections, classification of spatial changeability in land-cover. Different methods and formulas were used in the algorithm that successfully retrieves the land surface temperature to help us study the thermal environment of the ground surface. To verify the algorithm, the land surface temperature and the near-air temperature were compared. The results showed that, From 1996-2017, urban areas increased to about a considerable increase of about 48%. Few areas of the city also shown in a reduction in LST from the year 1996-2017 that actually began their transitional phase from rural to urban LULC. The mean temperature of the city increased averagely about 1ºC each year in the month of October. The green and vegetative areas witnessed a decrease in the area while a higher number of pixels increased in urban class.

Keywords: LST, LULC, isodata, urbanization

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1691 Environmental Degradation and Globalization with Special Reference to Developing Economics

Authors: Indira Sinha

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According to the Oxford Advanced Learner's English Dictionary of Current English, environment is the complex of physical, chemical and biotic factors that act upon an organism or an ecological community and ultimately determines its form and survival. It is defined as conditions and circumstances which are affecting people's lives. The meaning of environmental degradation is the degradation of the environment through depletion of resources such as air, water and soil and the destruction of ecosystems and extinction of wildlife. Globalization is a significant feature of recent world history. The aim of this phenomenon is to integrate societies, economies and cultures through a common link of trading policies, technology and communication. Undoubtedly it has opened up the world economy at a very high speed but at the same time it has an adverse impact on the environment. The purpose of the present study is to investigate the impact of globalization on the environmental conditions. An overview of what the forces of globalization have in store for the environment with constructing large number of industries and destroying large forests lands will be given in this paper. The forces of globalization have created many serious environmental problems like high temperature, extinction of many species of plant and animal and outlet of poisonous chemicals from industries. The revelation of this study is that in case of developing economics these problems are more critical. In developing countries like India many factories are built with less environmental regulations, while developed economies maintain positive environmental practices. The present study is a micro level study which aims to employ a combination of theoretical, descriptive, empirical and analytical approach in addition to the time tested case method.

Keywords: globalization, trade policies, environmental degradation, developing economies, large industries

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1690 Sustainable Renovation of Cultural Buildings Case Study: Red Bay National Historic Site, Canada

Authors: Richard Briginshaw, Hana Alaojeli, Javaria Ahmad, Hamza Gaffar, Nourtan Murad

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Sustainable renovations to cultural buildings and sites require a high level of competency in the sometimes conflicting areas of social/historical demands, environmental concerns, and the programmatic and technical requirements of the project. A detailed analysis of the existing site, building and client program are critical to reveal both challenges and opportunities. This forms the starting point for the design process – empirical explorations that search for a balanced and inspired architectural solution to the project. The Red Bay National Historic Site on the Labrador Coast of eastern Canada is a challenging project to explore and resolve these ideas. Originally the site of a 16ᵗʰ century whaling station occupied by Basque sailors from France and Spain, visitors now experience this history at the interpretive center, along with the unique geography, climate, local culture and vernacular architecture of the area. Working with our client, Parks Canada, the project called for significant alterations and expansion to the existing facility due to an increase in the number of annual visitors. Sustainable aspects of the design are focused on sensitive site development, passive energy strategies such as building orientation and building envelope efficiency, active renewable energy systems, carefully considered material selections, water efficiency, and interiors that respond to human comfort and a unique visitor experience.

Keywords: sustainability, renovations and expansion, cultural project, architectural design, green building

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1689 Investigating the Contribution of Road Construction on Soil Erosion, a Case Study of Engcobo Local Municipality, Chris Hani District, South Africa

Authors: Yamkela Zitwana

Abstract:

Soil erosion along the roads and/or road riparian areas has become a norm in the Eastern Cape. Soil erosion refers to the detachment and transportation of soil from one area (onsite) to another (offsite). This displacement or removal of soil can be caused by water, air and sometimes gravity. This will focus on accelerated soil erosion which is the result of human interference with the environment. Engcobo local municipality falls within the Eastern Cape Province in the eastern side of CHRIS HANI District municipality. The focus road is R61 protruding from the Engcobo town outskirts along the Nyanga SSS on the way to Umtata although it will cover few Kilometers away from Engcobo. This research aims at looking at the contribution made by road construction to soil erosion. Steps to achieve the result will involve revisiting the phases of road construction through unstructured interviews, identifying the types of soil erosion evident in the area by doing a checklist, checking the material, utensils and equipment used for road construction and the contribution of road construction through stratified random sampling checking the soil color and texture. This research will use a pragmatic approach which combines related methods and consider the flaws of each method so as to ensure validity, precision and accuracy. Both qualitative and quantitative methods will be used. Statistical methods and GIS analysis will be used to analyze the collected data.

Keywords: soil erosion, road riparian, accelerated soil erosion, road construction, sampling, universal soil loss model, GIS analysis, focus groups, qualitative, quantitative method, research, checklist questionnaires, unstructured interviews, pragmatic approach

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1688 Investigation the Photocatalytic Properties of Fe3O4-TiO2 Nanocomposites Prepared by Sonochemical Method

Authors: Zh. Saffari, A. Naeimi, M. S. Ekrami-Kakhki, F. Hamidi

Abstract:

Fe3O4 is one of the important magnetic oxides with spinel structure; it has exhibited unique electric and magnetic properties based on the electron transfer between Fe2+ and Fe3+ in the octahedral sites. Fe3O4 has received considerable attention in various areas such as cancer therapy, drug targeting, enzyme immobilization catalysis, magnetic cell separation, magnetic refrigeration systems and super-paramagnetic materials Fe3O4–TiO2 nanostructures were synthesized by simple, effective and new co-precipitation method assisted by ultrasonic reaction at room temperatures with organic surfactant. The effect of various parameters such as temperature, time, and power on the size and morphology of the product was investigated. Alternating gradient force magnetometer shows that Fe3O4 nanoparticles exhibit super-paramagnetic behaviour at room temperature. For preparation of nanocomposite, 1 g of TiO2 nanostructures were dispersed in 100 mL of ethanol. 0.25 g of Fe(NO3)2 and 2 mL of octanoic acid was added to the solution as a surfactant. Then, NaOH solution (1.5 M) was slowly added into the solution until the pH of the mixture was 7–8. After complete precipitation, the solution placed under the ultrasonic irradiation for 30 min. The product was centrifuged, washed with distilled water and dried in an oven at 100 °C for 3 h. The resulting red powder was calcinated at 800 °C for 3 h to remove any organic residue. The photocatalytic behaviour of Fe3O4–TiO2 nanoparticles was evaluated using the degradation of a Methyl Violet (MV) aqueous solution under ultraviolet light irradiation. As time increased, more and more MV was adsorbed on the nanoparticles catalyst, until the absorption peak vanish. The MV concentration decreased rapidly with increasing UV-irradiation time

Keywords: magnetic, methyl violet, nanocomposite, photocatalytic

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1687 Combined Effect of Moving and Open Boundary Conditions in the Simulation of Inland Inundation Due to Far Field Tsunami

Authors: M. Ashaque Meah, Md. Fazlul Karim, M. Shah Noor, Nazmun Nahar Papri, M. Khalid Hossen, M. Ismoen

Abstract:

Tsunami and inundation modelling due to far field tsunami propagation in a limited area is a very challenging numerical task because it involves many aspects such as the formation of various types of waves and the irregularities of coastal boundaries. To compute the effect of far field tsunami and extent of inland inundation due to far field tsunami along the coastal belts of west coast of Malaysia and Southern Thailand, a formulated boundary condition and a moving boundary condition are simultaneously used. In this study, a boundary fitted curvilinear grid system is used in order to incorporate the coastal and island boundaries accurately as the boundaries of the model domain are curvilinear in nature and the bending is high. The tsunami response of the event 26 December 2004 along the west open boundary of the model domain is computed to simulate the effect of far field tsunami. Based on the data of the tsunami source at the west open boundary of the model domain, a boundary condition is formulated and applied to simulate the tsunami response along the coastal and island boundaries. During the simulation process, a moving boundary condition is initiated instead of fixed vertical seaside wall. The extent of inland inundation and tsunami propagation pattern are computed. Some comparisons are carried out to test the validation of the simultaneous use of the two boundary conditions. All simulations show excellent agreement with the data of observation.

Keywords: open boundary condition, moving boundary condition, boundary-fitted curvilinear grids, far-field tsunami, shallow water equations, tsunami source, Indonesian tsunami of 2004

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1686 Allelopathic Potential of Canola and Wheat to Control Weeds in Soybean (Glycine max)

Authors: Alireza Dadkhah

Abstract:

A filed experiment was done to develop management practices to reduce the use of synthetic herbicides, in the arid and semi-arid agricultural ecosystems of north east of Iran. Five treatments including I: chopped residues of canola (Brasica vulgaris), II: chopped residues of wheat (Triticum aestivum) both were separately incorporated to 25 cm depth soil, 20 days before sowing, III: shoot aqueous extract of canola, IV: shoot aqueous extract of wheat which were separately sprayed at post emergence stage and V: without any residues and spraying as control. The weed control treatments reduced the total weed cover, weed density and biomass of weed. The reduction in weed density with canola and wheat residues incorporation were up to 67.5 and 62.2% respectively, at 40 days after sowing and 65.3% and 75.6%, respectively, at 90 days after sowing, compared to control. However, post emergence spraying of shoot aqueous extract of canola and wheat, suppressed weed density up to 41.8 and 36.6% at 40 days after sowing and 54.2% and 52.7% at 90 days after sowing respectively, compared to control. Weed control treatments reduced weed cover (%), weed biomass and weeds stem length. Incorporation of canola and wheat residues in soil reduced weed cover (%) by 62.5% and 63% respectively, while spraying of shoot water extract of canola and wheat suppressed weed cover (%) by 39.6% and 40.4% respectively at 90 days after sowing. Application of canola and wheat residues increased soybean yield by 45.4% and 69.5% respectively, compared to control while post emergence application of shoot aqueous extract of canola and wheat increased soybean yield by 22% and 29.8% respectively.

Keywords: allelopathy, Bio-herbicide, Brassica oleracea, plant residues, Triticum aestivum

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1685 Effects of Bile Acids and Lipase Supplementation in Low-Energy Diets on Growth Performance and Meat Quality in Broiler Chickens

Authors: Muhammad Adeel Arshad, Shaukat Ali Bhatti

Abstract:

The study aimed to investigate the effect of bile acids and lipase supplementation in low-energy diets on growth performance and meat quality of broilers. Seven hundred day-old Cobb-500 broiler chicks with an average initial body weight of 45.9 ± 0.3 g were assigned to 5 dietary treatments, with five replications of 28 birds each in a completely randomized design. The five treatments were as follows: (i) HE: broilers received a diet with high energy content; (ii) LE: broilers received a diet with low energy content and energy content reduced by 100 kcal/kg as compared to HE; (iii) LEB: broilers received a diet similar to the LE group supplemented with 300 g/ton bile acids; (iv) LEL: broilers received a diet similar to the LE group supplemented with 180 g/ton lipase enzyme and (v) LEBL: broilers received a diet similar to the LE group supplemented with both 300 g/ton bile acids and 180 g/ton lipase enzyme. The experimental period lasted for 35 days. Broilers fed HE had a lower (P < 0.05) body weight (BW) gain and lower feed intake (1-35 d), but during finisher period (21-35 d), BW gain was similar with other treatments. Feed conversion ratio (FCR) was lower in HE and higher in LEBL group (P < 0.05), while the LE, LEB, and LEL had intermediate values. At 35 d no difference occurred between treatment for water holding capacity and pH of breast and thigh muscles (P > 0.05). The relative weight of pancreas was higher (P < 0.05) in LEB treatment but lower (P < 0.05) in LEL treatment. In conclusion, bile acids and lipase supplementation at 300 g/ton and 150g/ton of feed in low-energy diets respectively had no effect on broiler performance and meat quality. However, FCR was improved in HE treatment.

Keywords: bile acids, energy, enzyme, growth

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1684 Analyzing Environmental Emotive Triggers in Terrorist Propaganda

Authors: Travis Morris

Abstract:

The purpose of this study is to measure the intersection of environmental security entities in terrorist propaganda. To the best of author’s knowledge, this is the first study of its kind to examine this intersection within terrorist propaganda. Rosoka, natural language processing software and frame analysis are used to advance our understanding of how environmental frames function as emotive triggers. Violent jihadi demagogues use frames to suggest violent and non-violent solutions to their grievances. Emotive triggers are framed in a way to leverage individual and collective attitudes in psychological warfare. A comparative research design is used because of the differences and similarities that exist between two variants of violent jihadi propaganda that target western audiences. Analysis is based on salience and network text analysis, which generates violent jihadi semantic networks. Findings indicate that environmental frames are used as emotive triggers across both data sets, but also as tactical and information data points. A significant finding is that certain core environmental emotive triggers like “water,” “soil,” and “trees” are significantly salient at the aggregate level across both data sets. All environmental entities can be classified into two categories, symbolic and literal. Importantly, this research illustrates how demagogues use environmental emotive triggers in cyber space from a subcultural perspective to mobilize target audiences to their ideology and praxis. Understanding the anatomy of propaganda construction is necessary in order to generate effective counter narratives in information operations. This research advances an additional method to inform practitioners and policy makers of how environmental security and propaganda intersect.

Keywords: propaganda analysis, emotive triggers environmental security, frames

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1683 Oxalate Content of Raw and Cooked Amaranth and Strawberry Spinach Grown in an Elevated CO₂ Atmosphere

Authors: Madhuri Kanala, Geoffrey Savage

Abstract:

Worldwide CO₂ levels are slowly rising, and this may have effects on the growth and nutritional composition of many food plants. The production of secondary metabolites such as oxalates has not been investigated in depth. The oxalate content of many food plants are known to have adverse nutritional effects on humans and reduction in the oxalate contents of food plants is a very positive move. Recent studies had shown that the oxalate content of the leaves of spinach and silver beet reduced when the plants were grown in an environment where CO₂ was increased. The response of amaranth and strawberry spinach leaves to changes in the high CO₂ environment have not been understood though it is known that the plants do contain appreciable oxalate contents. A study was conducted where amaranth and strawberry spinach plants were grown in identical plant growth chambers with the same environmental conditions except that one chamber was supplied with ambient air (CO₂ 405 ppm) while the other chamber had the CO₂ level increased to 650 ppm. The total and soluble oxalate content of the leaves of raw and cooked amaranth and strawberry spinach were determined by HPLC and calcium levels were determined using ICP following 6 weeks of growth. The total oxalate content of the fresh leaves of amaranth and strawberry spinach were reduced by 29.5 % and 24.6% respectively in the leaves of the plants grown in increased CO₂ conditions compared to ambient levels. The soluble oxalate content of amaranth leaves grown under ambient and increased CO₂ conditions were future reduced by 42% and 26.8% respectively following cooking as the soluble oxalate was leached into the cooking water and discarded. The reduction of the oxalate and calcium levels of raw and cooked amaranth and strawberry spinach leaves following an increase in CO₂ content in the air is an interesting positive response to an otherwise significant environmental problem.

Keywords: amaranth, calcium oxalate, enriched CO₂, oxalates, strawberry spinach

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1682 Injection of Bradykinin in Femoral Artery Elicits Cardiorespiratory Reflexes Involving Perivascular Afferents in Rat Models

Authors: Sanjeev K. Singh, Maloy B. Mandal, Revand R.

Abstract:

The physiology of baroreceptors and chemoreceptors present in large blood vessels of the heart is well known in regulation of cardiorespiratory functions. Since large blood vessels and peripheral blood vessels are of same mesodermal origin, therefore, involvement of the latter in regulation of cardiorespiratory system is expected. Role of perivascular nerves in mediating cardiorespiratory alterations produced after intra-arterial injection of a nociceptive agent (bradykinin) was examined in urethane anesthetized male rats. Respiratory frequency, blood pressure, and heart rate were recorded for 30 min after the retrograde injection of bradykinin/saline in the femoral artery. In addition, paw edema was determined and water content was expressed as percentage of wet weight. Injection of bradykinin produced immediate tachypnoeic, hypotensive and bradycardiac responses of shorter latency (5-8 s) favoring the neural mechanisms involved in it. Injection of equi-volume of saline did not produce any responses and served as time matched control. Paw edema was observed in the ipsilateral hind limb. Pretreatment with diclofenac sodium significantly attenuated the bradykinin-induced responses and also blocked the paw edema. Ipsilateral femoral and sciatic nerve sectioning attenuated bradykinin-induced responses significantly indicating the origin of responses from the local vascular bed. Administration of bradykinin in the segment of an artery produced reflex cardiorespiratory changes by stimulating the perivascular nociceptors involving prostaglandins. This is a novel study exhibiting the role of peripheral blood vessels in regulation of cardiorespiratory system.

Keywords: vasosensory reflex, cardiorespiratory changes, nociceptive agent, bradykinin, VR1 receptors

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1681 Brazil's Olympian Tragedy: Searching for Citizenship in Vila Autodromo

Authors: Rachel K. Cremona

Abstract:

Forty years ago, Vila Autodromo was a small fishing settlement in southwest Rio de Janeiro. By 2012, Vila Autodromo had established itself into a working class neighborhood – certainly not a slum, but nonetheless designated as a ‘favela’ as a consequence of its history as an illegal settlement that was thus never provided with public services. Vila Autodromo sits on a large lagoon, adjacent to the Olympic Park being constructed for the 2016 Olympic Games to be held in Rio, and looks out over the expensive high rise condominiums that have sprouted across the water. In 2009, when Rio submitted their bid for the Olympic games, there were approximately 900 families that called Vila Autodromo home, and the original plans for the games clearly show their homes remaining in place. Today, only a handful of these homes remain. This paper will utilize the case study of Vila Autodromo to examine the broader issue of Favelas in 21st century Rio de Janeiro. While race and poverty have become synonymous with Brazil’s inegalitarian social order – and personified by the thousands of favelas scattered in and around large cities like Rio and Sao Paulo – much less attention has been given to the political status of the nation’s invisible majority. In particular, this research will examine the question of citizenship and argue that the most fundamental problem of inequality in Brazil is not simply a product of history, race and social order, but more specifically a problem of ‘personhood’. The political marginalization of Brazil’s poor does not simply reinforce their social marginalization, it institutionalizes it in a way that makes it almost impossible to escape. The story of Vila Autodromo captures this problem in a way that not only illustrates the clear (though ambiguous) role of the state in the perpetuation of Brazil’s underclass, but also the human resilience that it has fostered.

Keywords: citizenship, poverty, displacement, favela

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1680 Pharmacodynamic Interaction between Tamsulosin and Finasteride Treatment on Induced Benign Prostate Hyperplasia in Mice by Using Chou-Talalay Method

Authors: Firas Rashad Al-Samarai

Abstract:

Introduction: Benign prostatic hyperplasia (BPH) is a common condition as men get older. An enlarged prostate gland can cause uncomfortable urinary symptoms, such as blocking the flow of urine out of the bladder. It can also cause bladder, urinary tract, or kidney problems. Objective: to evaluate the efficacy and interaction of tamsulosin with finasteride treatment on induced benign prostate hyperplasia (BPH) in mice. Methods: BPH was induced by subcutaneous injection of testosterone propionate (20 mg/kg) for 30 days. Eighty-five mice were divided into five groups. The first group (G1): twenty-five mice induced BPH treated with tamsulosin orally and divided into five equal subgroups with doses (0.017, 0.052, 0.087, 0. 123, and 0.158) mg/kg, the second group (G2): twenty-five mice induced BPH treated with finasteride orally and divided into five equal subgroups with doses (0.175, 0.527, 0.878, 1.23, and 1.580) mg/kg. the third group (G3): twenty-five mice induced BPH treated with a combination of tamsulosin with finasteride orally, and divided into five equal subgroups with doses (0.0085, 0.0875), (0.026, 0.2635), (0.0435, 0.439) , (0.0615, 0.615) and ( 0.079 , 0.790 ) mg/kg respectively. Fourth group (G4): five mice induced BPH and treated distilled water. Fifth group (G5): five mice were not inducing BPH and without any treatment. Results: The results showed a gradual significant increase in prostate weight % and prostate index % Inhibitions until reached saturation in the last two doses of tamsulosin, finasteride, and combination groups, the maximum effective dose of tamsulosin and finasteride were (0.156) and (1.495) mg/kg respectively. Moreover, the effective dose of the combination (tamsulosin and finasteride) was estimated (0.06876, 0.6876) mg/kg, respectively, as well as the type of interaction was synergism and the value of the combination index was 0.046. Conclusions: We concluded that the combination of tamsulosin with finasteride showed a synergistic effect in BPH treatment by minimizing the side effect of each drug as s result of decreasing the dose of each one.

Keywords: Tamsulosin, Finasteride, combination, BPH

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1679 Field Evaluation of Concrete Using Hawaiian Aggregates for Alkali Silica Reaction

Authors: Ian N. Robertson

Abstract:

Alkali Silica Reaction (ASR) occurs in concrete when the alkali hydroxides (Na, K and OH) from the cement react with unstable silica, SiO2, in some types of aggregate. The gel that forms during this reaction will expand when it absorbs water, potentially leading to cracking and overall expansion of the concrete. ASR has resulted in accelerated deterioration of concrete highways, dams and other structures that are exposed to moisture during their service life. Concrete aggregates available in Hawaii have not demonstrated a history of ASR, however, accelerated laboratory tests using ASTM 1260 indicated a potential for ASR with some aggregates. Certain clients are now requiring import of aggregates from the US mainland at great expense. In order to assess the accuracy of the laboratory test results, a long-term field study of the potential for ASR in concretes made with Hawaiian aggregates was initiated in 2011 with funding from the US Federal Highway Administration and Hawaii Department of Transportation. Thirty concrete specimens were constructed of various concrete mixtures using aggregates from all Hawaiian aggregate sources, and some US mainland aggregates known to exhibit ASR expansion. The specimens are located in an open field site in Manoa valley on the Hawaiian Island of Oahu, exposed to relatively high humidity and frequent rainfall. A weather station at the site records the ambient conditions on a continual basis. After two years of monitoring, only one of the Hawaiian aggregates showed any sign of expansion. Ten additional specimens were fabricated with this aggregate to confirm the earlier observations. Admixtures known to mitigate ASR, such as fly ash and lithium, were included in some specimens to evaluate their effect on the concrete expansion. This paper describes the field evaluation program and presents the results for all forty specimens after four years of monitoring.

Keywords: aggregate, alkali silica reaction, concrete durability, field exposure

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