Search results for: chloride attack
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1213

Search results for: chloride attack

343 Effect of Pretreatment and Drying Method on Selected Quality Parameters of Dried Bell Pepper

Authors: Toyosi Yewande Tunde-Akintunde, Grace Oluwatoyin Ogunlakin, Bosede Folake Olanipekun

Abstract:

Peppers are excellent sources of nutrients but its high moisture content makes it susceptible to spoilage. Drying, a common processing method, results in a reduction of these nutrients in the final product. Pre-treatment of pepper before drying can be used to reduce the level of degradation of nutrients. Thus this study investigated the effect of pre-treatment (hot water blanching and soaking in brine-sodium chloride) and drying methods (oven, microwave and sun) on selected quality parameters (proximate composition, capsaicin, reducing sugar and phenolic content, pH, total solid (TS), Titratable acidity (TA), water absorption capacity (WAC) and colour) of pepper. The protein and moisture content value ranged from 9.09 to 10.23% and 5.63 to 8.48% respectively. Sun dried samples had the highest value while oven dried samples had the lowest. Brine treated samples had higher protein but lower moisture content than blanched samples. Capsaicin, reducing sugar and phenolic content values ranged from 0.68 to 0.87 mg/dm3; 3.18 to 3.79 µg/ml; and 40.67 to 84.01 mg GAE/100 g d.m respectively. The sun dried samples had higher values while the lowest values were from microwave dried samples. The brine treated samples had higher values in capsaicin while the blanched samples had higher reducing sugar and phenolic contents. The values of L, a* and b* for the dried pepper varied from 58.76 to 63.13; 7.09 to 7.34; and 11.79 to 12.36 respectively. Oven dried samples had the lowest values for a*, while its L values were the highest. The L and a* values for brine treated samples were higher than blanched samples. The pre-treatment and drying method considered resulted in different values of the quality parameters considered which indicates that drying and pre-treatment has an effect on the quality of the final dried pepper samples.

Keywords: Bell pepper, microwave drying, oven drying, quality, sun drying

Procedia PDF Downloads 345
342 The Hair Growth Effects of Undariopsis peterseniana

Authors: Jung-Il Kang, Jeon Eon Park, Yu-Jin Moon, Young-Seok Ahn, Eun-Sook Yoo, Hee-Kyoung Kang

Abstract:

This study was conducted to evaluate the effect of Undariopsis peterseniana, a seaweed native to Jeju Island, Korea, on the growth of hair. The dermal papilla cells (DPCs) have known to regulate hair growth cycle and length of hair follicle through interact with epithelial cells. When immortalized vibrissa DPCs were treated with the U. peterseniana extract, the U. peterseniana extract significantly increased the proliferation of DPCs. The effect of U. peterseniana extract on the growth of vibrissa follicles was also examined. U. peterseniana extract significantly increased the hair-fiber lengths of the vibrissa follicles. Hair loss is partly caused by dihydrotestosterone (DHT) binding to androgen receptor in hair follicles, and the inhibition of 5α-reductase activity can prevent hair loss through the decrease of DHT level. The U. peterseniana extract inhibited 5α-reductase activity. Minoxidil, a potent hair-growth agent, can induce proliferation in NIH3T3 fibroblasts by opening KATP channels. We thus examined the proliferative effects of U. peterseniana extract in NIH3T3 fibroblasts. U. peterseniana extract significantly increased the proliferation of NIH3T3 fibroblasts. Tetraethylammonium chloride (TEA), a K+ channel blocker, inhibited U. peterseniana-induced proliferation in NIH3T3 fibroblasts. These results suggest that U. peterseniana could have the potential to treat alopecia through the proliferation of DPCs, the inhibition of 5α-reductase activity and the opening of KATP channels. [Acknowledgement] This research was supported by The Leading Human Resource Training Program of Regional Neo industry through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT and future Planning (2016H1D5A1908786).

Keywords: hair growth, Undariopsis peterseniana, vibrissa follicles, dermal papilla cells, 5α-reductase, KATP channels

Procedia PDF Downloads 298
341 Evaluation of Security and Performance of Master Node Protocol in the Bitcoin Peer-To-Peer Network

Authors: Muntadher Sallal, Gareth Owenson, Mo Adda, Safa Shubbar

Abstract:

Bitcoin is a digital currency based on a peer-to-peer network to propagate and verify transactions. Bitcoin is gaining wider adoption than any previous crypto-currency. However, the mechanism of peers randomly choosing logical neighbors without any knowledge about underlying physical topology can cause a delay overhead in information propagation, which makes the system vulnerable to double-spend attacks. Aiming at alleviating the propagation delay problem, this paper introduces proximity-aware extensions to the current Bitcoin protocol, named Master Node Based Clustering (MNBC). The ultimate purpose of the proposed protocol, that are based on how clusters are formulated and how nodes can define their membership, is to improve the information propagation delay in the Bitcoin network. In MNBC protocol, physical internet connectivity increases, as well as the number of hops between nodes, decreases through assigning nodes to be responsible for maintaining clusters based on physical internet proximity. We show, through simulations, that the proposed protocol defines better clustering structures that optimize the performance of the transaction propagation over the Bitcoin protocol. The evaluation of partition attacks in the MNBC protocol, as well as the Bitcoin network, was done in this paper. Evaluation results prove that even though the Bitcoin network is more resistant against the partitioning attack than the MNBC protocol, more resources are needed to be spent to split the network in the MNBC protocol, especially with a higher number of nodes.

Keywords: Bitcoin network, propagation delay, clustering, scalability

Procedia PDF Downloads 115
340 Aerodynamic Heating and Drag Reduction of Pegasus-XL Satellite Launch Vehicle

Authors: Syed Muhammad Awais Tahir, Syed Hossein Raza Hamdani

Abstract:

In the last two years, there has been a substantial increase in the rate of satellite launches. To keep up with the technology, it is imperative that the launch cost must be made affordable, especially in developing and underdeveloped countries. Launch cost is directly affected by the launch vehicle’s aerodynamic performance. Pegasus-XL SLV (Satellite Launch Vehicle) has been serving as a commercial SLV for the last 26 years, commencing its commercial flight operation from the six operational sites all around the US and Europe, and the Marshal Islands. Aerodynamic heating and drag contribute largely to Pegasus’s flight performance. The objective of this study is to reduce the aerodynamic heating and drag on Pegasus’s body significantly for supersonic and hypersonic flight regimes. Aerodynamic data for Pegasus’s first flight has been validated through CFD (Computational Fluid Dynamics), and then drag and aerodynamic heating is reduced by using a combination of a forward-facing cylindrical spike and a conical aero-disk at the actual operational flight conditions. CFD analysis using ANSYS fluent will be carried out for Mach no. ranges from 0.83 to 7.8, and AoA (Angle of Attack) ranges from -4 to +24 degrees for both simple and spiked-configuration, and then the comparison will be drawn using a variety of graphs and contours. Expected drag reduction for supersonic flight is to be around 15% to 25%, and for hypersonic flight is to be around 30% to 50%, especially for AoA < 15⁰. A 5% to 10% reduction in aerodynamic heating is expected to be achieved for hypersonic regions. In conclusion, the aerodynamic performance of air-launched Pegasus-XL SLV can be further enhanced, leading to its optimal fuel usage to achieve a more economical orbital flight.

Keywords: aerodynamics, pegasus-XL, drag reduction, aerodynamic heating, satellite launch vehicle, SLV, spike, aero-disk

Procedia PDF Downloads 105
339 Development of Hydrophilic Materials for Nanofiltration Membrane Achieving Dual Resistance to Fouling and Chlorine

Authors: Xi Quan Cheng, Yan Chao Xu, Xu Jiang, Lu Shao, Cher Hon Lau

Abstract:

A hydrophilic thin-film-composite (TFC) nanofiltration (NF) membrane has been developed through the interfacial polymerization (IP) of amino-functional polyethylene glycol (PEG) and trimesoyl chloride. The selective layer is formed on a polyethersulfone (PES) support that is characterized using FTIR, XPS and SEM, and is dependent on monomer immersion duration, and the concentration of monomers and additives. The higher hydrophilicity alongside the larger pore size of the PEG-based selective layer is the key to a high water flux of 66.0 L m-2 h-1 at 5.0 bar. With mean pore radius of 0.42 nm and narrow pore size distribution, the MgSO4 rejections of the PEG based PA TFC NF membranes can reach up to 80.2 %. The hydrophilic PEG based membranes shows positive charged since the isoelectric points range from pH=8.9 to pH=9.1 and the rejection rates for different salts of the novel membranes are in the order of R(MgCl2)>R(MgSO4)>R(NaCl)>R(Na2SO4). The pore sizes and water permeability of these membranes are tailored by varying the molecular weight and molecular architecture of amino-functional PEG. Due to the unique structure of the selective layer of the PEG based membranes consisting of saturated aliphatic construction unit (CH2-CH2-O), the membranes demonstrate dual resistance to fouling and chlorine. The membranes maintain good salt rejections and high water flux of PEG based membranes after treatment by 2000 ppm NaClO for 24 hours. Interestingly, the PEG based membranes exhibit excellent fouling resistance with a water flux recovery of 90.2 % using BSA as a model molecule. More importantly, the hydrophilic PEG based NF membranes have been exploited to separate several water soluble antibiotics (such as tobramycin, an aminoglycoside antibiotic applied in the treatment of various types of bacterial infections), showing excellent performance in concentration or removal of antibioics.

Keywords: nanofiltration, antibiotic separation, hydrophilic membrane, high flux

Procedia PDF Downloads 317
338 Activity Antidiarrheal Extract Kedondong Leaf in Balb/C Strain Male Mice Invivo

Authors: Johanrik, Arini Aprilliani, Fikri Haikal, Diyas Yuca, Muhammad A. Latif, Edijanti Goenarwo, Nurita P. Sari

Abstract:

Diarrhea is one of the leading causes of morbidity and mortality in many countries, as well as responsible for the deaths of millions of people each year. Previous research showed that the leaves, bark, and root bark of kedondong contains saponins, tannins, and flavonoids. Tannins have anti-diarrheal effects that work as the freeze of protein / astrigen, and may inhibit the secretion of chloride over the tannate bonding between protein in the intestines. Chemical compounds of flavonoids also have an effect as anti-diarrheal block receptors Cl ˉ in intestinal thus reducing the secretion of Cl ˉ to the intestinal lume. This research aims to know the anti-diarrheal activity of extracts kedondong leaf in mice Balb/C strain males in vivo. This research also proves kedondong leaves as an anti-diarrhea through trial efficacy of kedondong leaves as antisekretori and antimotilitas. This research using post-test only controlled group design. Analysis of statistical data normality and homogenity were tested by Kolmogorov Smirnov. If the data obtained homogenous then using ANOVA test. This research using ethanolic extracts kedondong leaf 200, 400 and 800 mg/kgBW to prove there is anti-diarrhea it makes into six treatment groups, for anti-secretory it makes into five treatment groups and anti-motility became five treatment groups. The result showed dose of ethanolic extracts kedondong leaf 800 mg/kgBW have significant value (p < 0.005). The conclusion from this extracts kedondong leaf research 800 mg/kgBW have pharmacological effects as antidiarrhea on Balb/C strain male mice with a mechanism of action as antisecretory and antimotility.

Keywords: anti-diarrhea, anti-secretory, anti-motility, kedondong leaf

Procedia PDF Downloads 462
337 Phytochemical Screening, Antimicrobial and Antioxidant Efficacy of the Endocarps Fruits of Argania spinosa (L.) Skeels (Sapotaceae) in Mostaganem

Authors: Sebaa H., Cherifi F., Djabeur Abderrezak M.

Abstract:

Argania spinosa, Sapotaceae sole representative in Algeria and Morocco; hence it is endemic in these regions. However, it is a recognised oil, forage, and timber tree highly adapted to aridity. The exploitation of the argan fruits produces considerable amounts of under or related products. These products, such as the endocarps of a fruit, recuperated after the use of kernels to extract oil. This research studies in detail the contents of total phenolic content was determined by Folin Ciocalteu reagent and Flavonoids by aluminum chloride colorimetric assay). Antioxidant activity of extracts was expressed as the percentage of DPPH radical inhibition and IC50 values (μg/mL). Antimicrobial activity evaluated using agar disk diffusion method against reference Pseudomonas aeruginosa ATTC 27453, Escherichia coli ATCC 23922. Immature endocarps showed a higher polyphenol content than mature endocarps. The total phenolic content in immature endocarps was found to vary from 983,75+ /- 0.45 to 980,1 +/- 0.43 mg gallic acid equivalents/g dry weight, whereas in mature endocarps, the polyphenol content ranged from 100,58 mg/g +/- 0.42 to 105 +/- 0.55% mg gallic acid equivalent / g dry weight. The flavonoid content was 16.5 mg equivalent catechin/g dry weight and 9.81mg equivalent catechin /g dry weight for immature and mature endocarp fruits, respectively. DPPH assay of the endocarps extract yielded a half-maximal effective concentration (IC50) value in the immature endocarps (549.33 μg/mL) than in mature endocarps (322 μg/mL). This result can be attributed to the higher phenolics and flavonoid compounds in the immature endocarps. Methanol extract of immature endocarps exhibited antibacterial activity against E.colie (inhibition zone, 11mm).

Keywords: antioxidant activity, antimicrobial activity, total phenolic content, DPPH assay

Procedia PDF Downloads 117
336 Potentiometric Determination of Moxifloxacin in Some Pharmaceutical Formulation Using PVC Membrane Sensors

Authors: M. M. Hefnawy, A. M. A. Homoda, M. A. Abounassif, A. M. Alanazia, A. Al-Majed, Gamal A. E. Mostafa

Abstract:

PVC membrane sensors using different approach e.g. ion-pair, ionophore, and Schiff-base has been used as testing membrane sensor. Analytical applications of membrane sensors for direct measurement of variety of different ions in complex biological and environmental sample are reported. The most important step of such PVC membrane sensor is the sensing active material. The potentiometric sensors have some outstanding advantages including simple design, operation, wide linear dynamic range, relative fast response time, and rotational selectivity. The analytical applications of these techniques to pharmaceutical compounds in dosage forms are also discussed. The construction and electrochemical response characteristics of Poly (vinyl chloride) membrane sensors for moxifloxacin HCl (MOX) are described. The sensing membranes incorporate ion association complexes of moxifloxacin cation and sodium tetraphenyl borate (NaTPB) (sensor 1), phosphomolybdic acid (PMA) (sensor 2) or phosphotungstic acid (PTA) (sensor 3) as electroactive materials. The sensors display a fast, stable and near-Nernstian response over a relative wide moxifloxacin concentration range (1 ×10-2-4.0×10-6, 1 × 10-2-5.0×10-6, 1 × 10-2-5.0×10-6 M), with detection limits of 3×10-6, 4×10-6 and 4.0×10-6 M for sensor 1, 2 and 3, respectively over a pH range of 6.0-9.0. The sensors show good discrimination of moxifloxacin from several inorganic and organic compounds. The direct determination of 400 µg/ml of moxifloxacin show an average recovery of 98.5, 99.1 and 98.6 % and a mean relative standard deviation of 1.8, 1.6 and 1.8% for sensors 1, 2, and 3 respectively. The proposed sensors have been applied for direct determination of moxifloxacin in some pharmaceutical preparations. The results obtained by determination of moxifloxacin in tablets using the proposed sensors are comparable favorably with those obtained using the US Pharmacopeia method. The sensors have been used as indicator electrodes for potentiometric titration of moxifloxacin.

Keywords: potentiometry, PVC, membrane sensors, ion-pair, ionophore, schiff-base, moxifloxacin HCl, sodium tetraphenyl borate, phosphomolybdic acid, phosphotungstic acid

Procedia PDF Downloads 439
335 Hydrometallurgical Processing of a Nigerian Chalcopyrite Ore

Authors: Alafara A. Baba, Kuranga I. Ayinla, Folahan A. Adekola, Rafiu B. Bale

Abstract:

Due to increasing demands and diverse applications of copper oxide as pigment in ceramics, cuprammonium hydroxide solution for rayon, p-type semi-conductor, dry cell batteries production and as safety disposal of hazardous materials, a study on the hydrometallurgical operations involving leaching, solvent extraction and precipitation for the recovery of copper for producing high grade copper oxide from a Nigerian chalcopyrite ore in chloride media has been examined. At a particular set of experimental parameter with respect to acid concentration, reaction temperature and particle size, the leaching investigation showed that the ore dissolution increases with increasing acid concentration, temperature and decreasing particle diameter at a moderate stirring. The kinetics data has been analyzed and was found to follow diffusion control mechanism. At optimal conditions, the extent of ore dissolution reached 94.3%. The recovery of the total copper from the hydrochloric acid-leached chalcopyrite ore was undertaken by solvent extraction and precipitation techniques, prior to the beneficiation of the purified solution as copper oxide. The purification of the leach liquor was firstly done by precipitation of total iron and manganese using Ca(OH)2 and H2O2 as oxidizer at pH 3.5 and 4.25, respectively. An extraction efficiency of 97.3% total copper was obtained by 0.2 mol/L Dithizone in kerosene at 25±2ºC within 40 minutes, from which ≈98% Cu from loaded organic phase was successfully stripped by 0.1 mol/L HCl solution. The beneficiation of the recovered pure copper solution was carried out by crystallization through alkali addition followed by calcination at 600ºC to obtain high grade copper oxide (Tenorite, CuO: 05-0661). Finally, a simple hydrometallurgical scheme for the operational extraction procedure amenable for industrial utilization and economic sustainability was provided.

Keywords: chalcopyrite ore, Nigeria, copper, copper oxide, solvent extraction

Procedia PDF Downloads 393
334 A Study on Marble-Slag Based Geopolymer Green Concrete

Authors: Zong-Xian Qiu, Ta-Wui Cheng, Wei-Hao Lee, Yung-Chin Ding

Abstract:

The greenhouse effect is an important issue since it has been responsible for global warming. Carbon dioxide plays an important part of role in the greenhouse effect. Therefore, human has the responsibility for reducing CO₂ emissions in their daily operations. Except iron making and power plants, another major CO₂ production industry is cement industry. According to the statistics by EPA of Taiwan, production 1 ton of Portland cement will produce 520.29 kg of CO₂. There are over 7.8 million tons of CO₂ produced annually. Thus, trying to development low CO₂ emission green concrete is an important issue, and it can reduce CO₂ emission problems in Taiwan. The purpose of this study is trying to use marble wastes and slag as the raw materials to fabricate geopolymer green concrete. The result shows the marble based geopolymer green concrete have good workability and the compressive strength after curing for 28 days and 365 days can be reached 44MPa and 53MPa in indoor environment, 28MPa and 40.43MPa in outdoor environment. The acid resistance test shows the geopolymer green concrete have good resistance for chemical attack. The coefficient of permeability of geopolymer green concrete is better than Portland concrete. By comparing with Portland cement products, the marble based geopolymer not only reduce CO₂ emission problems but also provides great performance in practices. According to the experiment results shown that geopolymer concrete has great potential for further engineering development in the future, the new material could be expected to replace the Portland cement products in the future days.

Keywords: marble, slag, geopolymer, green concrete, CO₂ emission

Procedia PDF Downloads 138
333 Wadi Halfa Oolitic Ironstone Formation, Wadi Halfa and Argein Areas, North Sudan

Authors: Mutwakil Nafi, Abed Elaziz El Amein, Muna El Dawi, Khalafala Salih, Osma Elbahi, Abed Elhalim Abou

Abstract:

Recently a large deposit of oolitic iron ore of Late Carboniferous-Permotriassic-Lower Jurassic age was discovered in Wadi Halfa and Argein areas, North Sudan. It seems that the iron ore mineralization exists in the west and east bank of the River Nile of the study area that are found on the Egyptian-Sudanese border. The Carboniferous-Lower Jurassic age strata were covered by 67 sections and each section has been examined and carefully described. The iron-ore in Wadi Halfa occurs as oolitic ironstone and contained two horizons: (A) horizon and (B) horizon. Only horizon (A) was observed in southern Argein area. The texture of the ore is variable depending on the volume of the component. In thin sections the average of the ooids were ranged between 90% - 80%. The matrix varies between 10%-20% by volume and detritus quartz in other component my reach up to 30% by volume in sandy massive ore. Ooids size ranges from 0.2mm-1.00 mm on average in very coarse ooids may attend up to 1 mm in size. The matrix around the ooids is dominated by iron hydroxide, carbonate, fine and amorphous silica. The probable ore reserve estimate of 1.234 billion at a head grade of 41.29% Fe for the Wadi Halfa Oolitic Ironstone Formation. The iron ore shows higher content of phosphorus ranges from 6.15% to 0.16%, with mean 1.45%. The new technology Hatch–Ironstone Chloride Segregation (HICS) can be used to produce commercial-quality of iron and reduce phosphorus and silica to acceptable levels for steel industry. The development of infra structures and presence huge quantity of iron ore would make exploitation of the iron ore economic.

Keywords: HICS, Late Carboniferous age, oolitic iron ore, phosphorus

Procedia PDF Downloads 647
332 Modeling of Glycine Transporters in Mammalian Using the Probability Approach

Authors: K. S. Zaytsev, Y. R. Nartsissov

Abstract:

Glycine is one of the key inhibitory neurotransmitters in Central nervous system (CNS) meanwhile glycinergic transmission is highly dependable on its appropriate reuptake from synaptic cleft. Glycine transporters (GlyT) of types 1 and 2 are the enzymes providing glycine transport back to neuronal and glial cells along with Na⁺ and Cl⁻ co-transport. The distribution and stoichiometry of GlyT1 and GlyT2 differ in details, and GlyT2 is more interesting for the research as it reuptakes glycine to neuron cells, whereas GlyT1 is located in glial cells. In the process of GlyT2 activity, the translocation of the amino acid is accompanied with binding of both one chloride and three sodium ions consequently (two sodium ions for GlyT1). In the present study, we developed a computer simulator of GlyT2 and GlyT1 activity based on known experimental data for quantitative estimation of membrane glycine transport. The trait of a single protein functioning was described using the probability approach where each enzyme state was considered separately. Created scheme of transporter functioning realized as a consequence of elemental steps allowed to take into account each event of substrate association and dissociation. Computer experiments using up-to-date kinetic parameters allowed receiving the number of translocated glycine molecules, Na⁺ and Cl⁻ ions per time period. Flexibility of developed software makes it possible to evaluate glycine reuptake pattern in time under different internal characteristics of enzyme conformational transitions. We investigated the behavior of the system in a wide range of equilibrium constant (from 0.2 to 100), which is not determined experimentally. The significant influence of equilibrium constant in the range from 0.2 to 10 on the glycine transfer process is shown. The environmental conditions such as ion and glycine concentrations are decisive if the values of the constant are outside the specified range.

Keywords: glycine, inhibitory neurotransmitters, probability approach, single protein functioning

Procedia PDF Downloads 119
331 Root Cause Analysis of Surveillance Quality in Tanjung Priok Port to Prevent Epidemic Potential Disease as a Form of Bioterrorism Threat

Authors: Dina A. Amu, Fifi N. Afifah, Catur Rosidati, Tirton Nefianto

Abstract:

Indonesia was shaken up by the avian influenza cases that had caused the country suffered losses of millions of dollars. The avian influenza case had even been suspected as a bioterrorism attack since it was an uncommon case in epidemiology. Furthermore, this avian influenza virus is a high pathogenic one and Indonesia has the highest case of fatality rate in the world. Bioterrorism threats or epidemic potential disease outbreaks currently does not exist in Tanjung Priok port yet. However, the surveillance system enhancement on epidemic potential diseases should be taken as a prevention, especially because Indonesia is currently facing the ASEAN Economic Society (AES). Therefore, this research evaluates the health surveillance system which is organized by Control, Quarantine and Surveillance Department, Health Office of Tanjung Priok Port. This study uses qualitative-evaluative method which utilizes Urgency Seriousness Growth (USG) method to determine priority issues and Root Cause analysis to determine the cause of prior problem. The result of this research shows that the implementation of epidemic potential disease surveillance in Tanjung Priok port has not done in the best possible way. It is because the lack of time allocation and the succinctness of the check list of ship's environmental health inspection. Therefore, Health Ministry of Indonesia should recruit more employees at the health office of Tanjung Priok port, hold a simulation of ship's inspection and simplify the list for ship's environmental health inspection.

Keywords: surveillance, epidemic potential disease, port health, bioterrorism

Procedia PDF Downloads 363
330 Possible Neuroprotective Mechanism of Remote Limb Ischemic Post Conditioning against Global Cerebral Ischemic Injury

Authors: Sruthi Ramagiri, Rajeev Taliyan

Abstract:

Background and purpose: Recent investigations on ischemia and reperfusion injury postulate that transient ischemia of remote organs after a prolonged ischemic insult confers neuroprotection. However, the molecular mechanisms of the remote limb ischemic post-conditioning (RIPOC) are yet to be elucidated. The current study was designed to investigate the protective mechanism of RIPOC against cerebral ischemic injury using global model of stroke. Materials and methods: Global ischemic reperfusion injury (IR) was achieved by 30 minutes ischemia of cerebral artery, followed by reperfusion for 24 hours. Induction of global ischemia was followed by 4 brief episodes (30 seconds each) of ischemia and reperfusion of femoral artery to accomplish RIPOC. 5-Hydroxy Decanoic acid (5-HD), a KATP channel blocker (20 mg/kg) was administered after induction of global ischemia and RIPOC intervention. Results: IR injury ensue significant behavioural deficits as manifested by rotarod performance and spontaneous locomotor activity when compared to sham control. Furthermore, IR injury significantly increased oxidonitrative stress and infarct volume as evidenced by biochemical parameters (MDA, GSH, Nitrite, SOD) and 2,3,5-triphenyltetrazolium chloride (TTC) staining respectively. Moreover, RIPOC intervention ameliorated the behavioural performance, attenuated the oxidative stress and infarct volume when compared to IR injury group. However, administration of 5-HD increased the oxidative stress and infarct size while deteriorating the behavioural parameters when compared to RIPOC group. Conclusions: In a nutshell, cerebral IR injury has significantly induced the neuronal damage, whereas RIPOC intervention decreased the neuronal injury. Moreover, 5-HD abolished the neuroprotection offered by RIPOC indicating the putative role of KATP channel opening in RIPOC against cerebral ischemic injury.

Keywords: RIPOC, cerebral injury, KATP channel, neuroprotection

Procedia PDF Downloads 470
329 Framing Mahsa Amini and Iran Protest: A Comparative Analysis of Tehran times and the Wall Street Journal

Authors: Nimmy Maria Joseph, Muhammed Hafiludheen

Abstract:

On September 16, a 22-year-old Iranian woman, Mahsa Amini, died in Tehran after she was arrested by the ‘Morality police’ for an accusation of not wearing a hijab according to the standards laid down by the Iran Government. Suspicions aroused as the incident happened while Mahsa Amini was under the custody of Iran police. People of Iran accused that she was severely beaten up by the police, which led to her death. This initiated an array of women-led protests in Iran, leading to the ignition of massive uproars in the country. The Law Enforcement Command of Iran reported that she collapsed due to a heart attack and not due to police brutality. However, as a result, Iran faced a series of conflicts between the Government of Iran and the civilians, especially women. The research paper presents the framing analysis of online news stories on Mahsa Amini’s death and the resultant protest in Iran. The researcher analysed the online news stories of two popular newspapers, Tehran Times (Iran) and The Wall Street Journal (USA). The focus of the study is to have a comparative analysis of the frames of the news stories used and find out their agenda-setting pattern. It helps to comprehend how the news stories of popular news organisations try to channelise the perception of their audience on social issues. The researcher analysed the news stories considering their frames, valence, polysemy, rhetoric devices, and technical devices.

Keywords: mahsa amini, iran protest, framing analysis, valence, rhetoric device, tehran times, the wall street journal

Procedia PDF Downloads 99
328 Anti-Diarrheal Activity of Extracts Kedondong Leaf in Mice Balb/C Strain Males in Vivo

Authors: Johanrik, Arini Apriliani, Fikri Haikal, Dias Yuca, Muhammad Abdul Latif, Edijanti Goenarwo, Nurita Pratama Sari

Abstract:

Diarrhea is one of the leading causes of morbidity and mortality in many countries, as well as responsible for the deaths of millions of people each year. Previous research showed that the leaves, bark, and root bark of kedondong contains saponins, tannins, and flavonoids. Tannins have anti-diarrheal effects that work as the freeze of protein/astringent, and may inhibit the secretion of chloride over the tannate bonding between protein in the intestines. Chemical compounds of flavonoids also have an effect as anti-diarrheal block receptors Cl ˉ in intestinal thus reducing the secretion of Cl ˉ to the intestinal lume .This research aims to know the anti-diarrheal activity of extracts kedondong leaf in mice Balb/C strain males in vivo. This research also proves kedondong leaves as an anti-diarrhea through trial efficacy of kedondong leaves as antisekretori and antimotilitas. This research using post-test only controlled group design. Analysis of statistical data normality and homogenity were tested by Kolmogorov Smirnov. If the data obtained homogenous then using ANOVA test. This research using ethanolic extracts kedondong leaf 200, 400 and 800 mg/kgBW to prove there is anti-diarrhea it makes into six treatment groups, for anti-secretory it makes into five treatment groups and anti-motility became five treatment groups. The result showed dose of ethanolic extracts kedondong leaf 800 mg/kgBW have significant value (p<0.005). The conclusion from this extracts kedondong leaf research 800 mg/kgBW have pharmacological effects as antidiarrhea on Balb/C strain male mice with a mechanism of action as anti-secretory and anti-motility.

Keywords: anti-diarrhea, anti-secretory, anti-motility, kedondong leaf

Procedia PDF Downloads 508
327 Comparative Study of the Abundance of Winter Nests of the Pine Processionary Caterpillar in Different Forests of Pinus Halepensis, pinus Pinaster, Pinus Pinea and Cedrus Atlantica, in Algeria

Authors: Boudjahem Ibtissem, Aouati Amel

Abstract:

Thaumetopoea pityocampa is one of the major insect pests of pine forests in Algeria, the Mediterranean region, and central Europe. This pest is responsible for several natural and human damages these last years. The caterpillar can feed itself during the larval stage on several species of pine or cedar. The forests attack by the insect can reduce their resistance against other forest enemies, fires, or drought conditions. In this case, the tree becomes more vulnerable to other pests. To understand the eating behavior of the insect in its ecological conditions, and its nutritional preference, we realized a study of the abundance of winter nests of the pine processionary caterpillar in four different forests: Pinus halepensis; Pinus pinaster; Pinus pinea, and Cedrus atlantica. A count of the sites affected by the processionary caterpillar was carried out on a hundred trees from the forests in different regions in Algeria; Alkala region, Mila region, Annaba region, and Blida region; the total rate and average abundance are calculated for each forest. Ecological parameters are also estimated for each infestation. The results indicated a higher rate of infestation in Pinus halepensis trees (85%) followed by Cedrus atlantica (66%) and Pinus pinaster (50%) trees. The Pinus pinea forest is the least attacked region by the pine processionary caterpillar (23%). The abundance of the pine processionary caterpillar can be influenced by the height of the trees, the climate of the region, the age of the forest but also the quality of needles.

Keywords: Thaumetopoea pityocampa, Pinus halepensis, needles, winter nests

Procedia PDF Downloads 150
326 DOG1 Expression Is in Common Human Tumors: A Tissue Microarray Study on More than 15,000 Tissue Samples

Authors: Kristina Jansen, Maximilian Lennartz, Patrick Lebok, Guido Sauter, Ronald Simon, David Dum, Stefan Steurer

Abstract:

DOG1 (Discovered on GIST1) is a voltage-gated calcium-activated chloride and bicarbonate channel that is highly expressed in interstitial cells of Cajal and in gastrointestinal stromal tumors (GIST) derived from Cajal cells. To systematically determine in what tumor entities and normal tissue types DOG1 may be further expressed, a tissue microarray (TMA) containing 15,965 samples from 121 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. DOG1 immunostaining was found in 67 tumor types, including GIST (95.7%), esophageal squamous cell carcinoma (31.9%), pancreatic ductal adenocarcinoma (33.6%), adenocarcinoma of the Papilla Vateri (20%), squamous cell carcinoma of the vulva (15.8%) and the oral cavity (15.3%), mucinous ovarian cancer (15.3%), esophageal adenocarcinoma (12.5%), endometrioid endometrial cancer (12.1%), neuroendocrine carcinoma of the colon (11.1%) and diffuse gastric adenocarcinoma (11%). Low level-DOG1 immunostaining was seen in 17 additional tumor entities. DOG1 expression was unrelated to histopathological parameters of tumor aggressiveness and/or patient prognosis in cancers of the breast (n=1,002), urinary bladder (975), ovary (469), endometrium (173), stomach (233), and thyroid gland (512). High DOG1 expression was linked to estrogen receptor expression in breast cancer (p<0.0001) and the absence of HPV infection in squamous cell carcinomas (p=0.0008). In conclusion, our data identify several tumor entities that can show DOG1 expression levels at similar levels as in GIST. Although DOG1 is tightly linked to a diagnosis of GIST in spindle cell tumors, the differential diagnosis is much broader in DOG1 positive epithelioid neoplasms.

Keywords: biomarker, DOG1, immunohistochemistry, tissue microarray

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325 Role of Microplastics on Reducing Heavy Metal Pollution from Wastewater

Authors: Derin Ureten

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Plastic pollution does not disappear, it gets smaller and smaller through photolysis which are caused mainly by sun’s radiation, thermal oxidation, thermal degradation, and biodegradation which is the action of organisms digesting larger plastics. All plastic pollutants have exceedingly harmful effects on the environment. Together with the COVID-19 pandemic, the number of plastic products such as masks and gloves flowing into the environment has increased more than ever. However, microplastics are not the only pollutants in water, one of the most tenacious and toxic pollutants are heavy metals. Heavy metal solutions are also capable of causing varieties of health problems in organisms such as cancer, organ damage, nervous system damage, and even death. The aim of this research is to prove that microplastics can be used in wastewater treatment systems by proving that they could adsorb heavy metals in solutions. Experiment for this research will include two heavy metal solutions; one including microplastics in a heavy metal contaminated water solution, and one that just includes heavy metal solution. After being sieved, absorbance of both mediums will be measured with the help of a spectrometer. Iron (III) chloride (FeCl3) will be used as the heavy metal solution since the solution becomes darker as the presence of this substance increases. The experiment will be supported by Pure Nile Red powder in order to observe if there are any visible differences under the microscope. Pure Nile Red powder is a chemical that binds to hydrophobic materials such as plastics and lipids. If proof of adsorbance could be observed by the rates of the solutions' final absorbance rates and visuals ensured by the Pure Nile Red powder, the experiment will be conducted with different temperature levels in order to analyze the most accurate temperature level to proceed with removal of heavy metals from water. New wastewater treatment systems could be generated with the help of microplastics, for water contaminated with heavy metals.

Keywords: microplastics, heavy metal, pollution, adsorbance, wastewater treatment

Procedia PDF Downloads 87
324 Synthetic Bis(2-Pyridylmethyl)Amino-Chloroacetyl Chloride- Ethylenediamine-Grafted Graphene Oxide Sheets Combined with Magnetic Nanoparticles: Remove Metal Ions and Catalytic Application

Authors: Laroussi Chaabane, Amel El Ghali, Emmanuel Beyou, Mohamed Hassen V. Baouab

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In this research, the functionalization of graphene oxide sheets by ethylenediamine (EDA) was accomplished and followed by the grafting of bis(2-pyridylmethyl) amino group (BPED) onto the activated graphene oxide sheets in the presence of chloroacetylchloride (CAC) and then combined with magnetic nanoparticles (Fe₃O₄NPs) to produce a magnetic graphene-based composite [(Go-EDA-CAC)@Fe₃O₄NPs-BPED]. The physicochemical properties of [(Go-EDA-CAC)@Fe₃O₄NPs-BPED] composites were investigated by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA). Additionally, the catalysts can be easily recycled within ten seconds by using an external magnetic field. Moreover, [(Go-EDA-CAC)@Fe₃O₄NPs-BPED] was used for removing Cu(II) ions from aqueous solutions using a batch process. The effect of pH, contact time and temperature on the metal ions adsorption were investigated, however weakly dependent on ionic strength. The maximum adsorption capacity values of Cu(II) on the [(Go-EDA-CAC)@Fe₃O₄NPs-BPED] at the pH of 6 is 3.46 mmol.g⁻¹. To examine the underlying mechanism of the adsorption process, pseudo-first, pseudo-second-order, and intraparticle diffusion models were fitted to experimental kinetic data. Results showed that the pseudo-second-order equation was appropriate to describe the Cu (II) adsorption by [(Go-EDA-CAC)@Fe₃O₄NPs-BPED]. Adsorption data were further analyzed by the Langmuir, Freundlich, and Jossens adsorption approaches. Additionally, the adsorption properties of the [(Go-EDA-CAC)@Fe₃O₄NPs-BPED], their reusability (more than 6 cycles) and durability in the aqueous solutions open the path to removal of Cu(II) from water solution. Based on the results obtained, we report the activity of Cu(II) supported on [(Go-EDA-CAC)@Fe₃O₄NPs-BPED] as a catalyst for the cross-coupling of symmetric alkynes.

Keywords: graphene, magnetic nanoparticles, adsorption kinetics/isotherms, cross coupling

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323 Hydro-Geochemistry of Qare-Sou Catchment and Gorgan Gulf, Iran: Examining Spatial and Temporal Distribution of Major Ions and Determining the River’s Hydro-Chemical Type

Authors: Milad Kurdi, Hadi Farhadian, Teymour Eslamkish

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This study examined the hydro-geochemistry of Qare-Sou catchment and Gorgan Gulf in order to determine the spatial distribution of major ions. In this regard, six hydrometer stations in the catchment and four stations in Gorgan Gulf were chosen and the samples were collected. Results of spatial and temporal distribution of major ions have shown similar variation trends for calcium, magnesium, and bicarbonate ions. Also, the spatial trend of chloride, sulfate, sodium and potassium ions were same as Electrical Conductivity (EC) and Total Dissolved Solid (TDS). In Nahar Khoran station, the concentrations of ions were more than other stations which may be related to human activities and the role of geology. The Siah Ab station’s ions showed high concentration which is may be related to the station’s close proximity to Gorgan Gulf and the return of water to Qare-Sou River. In order to determine the interaction of water and rock, the Gibbs diagram was used and the results showed that water of the river falls in the rock range and it is affected more by weathering and reaction between water and stone and less by evaporation and crystallization. Assessment of the quality of river water by using graphic methods indicated that the type of water in this area is Ca-HCO3-Mg. Major ions concentration in Qare-Sou in the universal average was more than but not more than the allowed limit by the World Health Organization and China Standard Organization. A comparison of ions concentration in Gorgan Gulf, seas and oceans showed that the pH in Gorgan Gulf was more than the other seas but in Gorgan Gulf the concentration of anion and cation was less than other seas.

Keywords: hydro-geochemistry, Qare-Sou river, Gorgan gulf, major ions, Gibbs diagram, water quality, graphical methods

Procedia PDF Downloads 316
322 The Role of Moroccan Salafist Radicalism in Creating Threat to Spain’s Security

Authors: Stanislaw Kosmynka

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Although the genesis of the activity of fighting salafist radicalism in Spain dates back to the 80’s, the development of extremism of this kind manifested itself only in the next decade. Its first permanently functioning structures in this country in the second half of 90’s of 20th century came from Algieria and Syria. At the same time it should be emphasized that this distinction is in many dimensions conventional, the more so because they consisted also of immigrants from other coutries of Islam, particularly from Morocco. The paper seeks to understand the radical salafist challenge for Spain in the context of some terrorist networks consisted of immigrants from Morocco. On the eve of the new millennium Moroccan jihadists played an increasingly important role. Although the activity of these groups had for many years mainly logistical and propaganda character, the bomb attack carried out on 11 March 2004 in Madrid constituted an expression of open forms of terrorism, directed against the authorities and society of Spain and reflected the narration of representatives of the trend of the global jihad. The people involved in carrying out that act of violence were to a large extent Moroccan immigrants; also in the following years among the cells of radicals in Spain Moroccans stood out many times. That is why the forms and directions of activity of these extremists in Spain, also after 11th March 2004 and in the actual context of the impact of Islamic State, are worth presenting. The paper is focused on threats to the security of Spain and the region and remains connected with the issues of mutual relations of the society of a host country with immigrant communities which to a large degree come from this part of Maghreb.

Keywords: jihadi terrorism, Morocco, radical salafism, security, Spain, terrorist cells, threat

Procedia PDF Downloads 525
321 Adverse Curing Conditions and Performance of Concrete: Bangladesh Perspective

Authors: T. Manzur

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Concrete is the predominant construction material in Bangladesh. In large projects, stringent quality control procedures are usually followed under the supervision of experienced engineers and skilled labors. However, in the case of small projects and particularly at distant locations from major cities, proper quality control is often an issue. It has been found from experience that such quality related issues mainly arise from inappropriate proportioning of concrete mixes and improper curing conditions. In most cases external curing method is followed which requires supply of adequate quantity of water along with proper protection against evaporation. Often these conditions are found missing in the general construction sites and eventually lead to production of weaker concrete both in terms of strength and durability. In this study, an attempt has been made to investigate the performance of general concreting works of the country when subjected to several adverse curing conditions that are quite common in various small to medium construction sites. A total of six different types of adverse curing conditions were simulated in the laboratory and samples were kept under those conditions for several days. A set of samples was also submerged in normal curing condition having proper supply of curing water. Performance of concrete was evaluated in terms of compressive strength, tensile strength, chloride permeability and drying shrinkage. About 37% and 25% reduction in 28-day compressive and tensile strength were observed respectively, for samples subjected to most adverse curing condition as compared to the samples under normal curing conditions. Normal curing concrete exhibited moderate permeability (close to low permeability) whereas concrete under adverse curing conditions showed very high permeability values. Similar results were also obtained for shrinkage tests. This study, thus, will assist concerned engineers and supervisors to understand the importance of quality assurance during the curing period of concrete.

Keywords: adverse, concrete, curing, compressive strength, drying shrinkage, permeability, tensile strength

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320 Performance of Autoclaved Aerated Concrete Containing Recycled Ceramic and Gypsum Waste as Partial Replacement for Sand

Authors: Efil Yusrianto, Noraini Marsi, Noraniah Kassim, Izzati Abdul Manaf, Hafizuddin Hakim Shariff

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Today, municipal solid waste (MSW), noise pollution, and attack fire are three ongoing issues for inhabitants of urban including in Malaysia. To solve these issues, eco-friendly autoclaved aerated concrete (AAC) containing recycled ceramic and gypsum waste (CGW) as a partial replacement for sand with different ratios (0%, 5%, 10%, 15%, 20%, and 25% wt) has been prepared. The performance of samples, such as the physical, mechanical, sound absorption coefficient, and direct fire resistance, has been investigated. All samples showed normal color behavior, i.e., grey and free crack. The compressive strength was increased in the range of 6.10% to 29.88%. The maximum value of compressive strength was 2.13MPa for 15% wt of CGW. The positive effect of CGW on the compressive strength of AAC has also been confirmed by crystalline phase and microstructure analysis. The acoustic performances, such as sound absorption coefficients of samples at low frequencies (500Hz), are higher than the reference sample (RS). AAC-CGW samples are categorized as AAC material classes B and C. The fire resistance results showed the physical surface of the samples had a free crack and was not burned during the direct fire at 950ºC for 300s. The results showed that CGW succeeded in enhancing the performance of fresh AAC, such as compressive strength, crystalline phase, sound absorption coefficient, and fire resistance of samples.

Keywords: physical, mechanical, acoustic, direct fire resistance performance, autoclaved aerated concrete, recycled ceramic-gypsum waste

Procedia PDF Downloads 138
319 Aeroacoustics Investigations of Unsteady 3D Airfoil for Different Angle Using Computational Fluid Dynamics Software

Authors: Haydar Kepekçi, Baha Zafer, Hasan Rıza Güven

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Noise disturbance is one of the major factors considered in the fast development of aircraft technology. This paper reviews the flow field, which is examined on the 2D NACA0015 and 3D NACA0012 blade profile using SST k-ω turbulence model to compute the unsteady flow field. We inserted the time-dependent flow area variables in Ffowcs-Williams and Hawkings (FW-H) equations as an input and Sound Pressure Level (SPL) values will be computed for different angles of attack (AoA) from the microphone which is positioned in the computational domain to investigate effect of augmentation of unsteady 2D and 3D airfoil region noise level. The computed results will be compared with experimental data which are available in the open literature. As results; one of the calculated Cp is slightly lower than the experimental value. This difference could be due to the higher Reynolds number of the experimental data. The ANSYS Fluent software was used in this study. Fluent includes well-validated physical modeling capabilities to deliver fast, accurate results across the widest range of CFD and multiphysics applications. This paper includes a study which is on external flow over an airfoil. The case of 2D NACA0015 has approximately 7 million elements and solves compressible fluid flow with heat transfer using the SST turbulence model. The other case of 3D NACA0012 has approximately 3 million elements.

Keywords: 3D blade profile, noise disturbance, aeroacoustics, Ffowcs-Williams and Hawkings (FW-H) equations, k-ω-SST turbulence model

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318 Effect of Silica Fume at Cellular Sprayed Concrete

Authors: Kyong-Ku Yun, Seung-Yeon Han, Kyeo-Re Lee

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Silica fume which is a super-fine byproduct of ferrosilicon or silicon metal has a filling effect on micro-air voids or a transition zone in a hardened cement paste by appropriate mixing, placement, and curing. It, also, has a Pozzolan reaction which enhances the interior density of the hydrated cement paste through a formation of calcium silicate hydroxide. When substituting cement with silica fume, it improves water tightness and durability by filling effect and Pozzolan reaction. However, it needs high range water reducer or super-plasticizer to distribute silica fume into a concrete because of its finesses and high specific surface area. In order to distribute into concrete evenly, cement manufacturers make a pre-blended cement of silica fume and provide to a market. However, a special mixing procedures and another transportation charge another cost and this result in a high price of pre-blended cement of silica fume. The purpose of this dissertation was to investigate the dispersion of silica fume by air slurry and its effect on the mechanical properties of at ready-mixed concrete. The results are as follows: A dispersion effect of silica fume was measured from an analysis of standard deviation for compressive strength test results. It showed that the standard deviation decreased as the air bubble content increased, which means that the dispersion became better as the air bubble content increased. The test result of rapid chloride permeability test showed that permeability resistance increased as the percentages of silica fume increased, but the permeability resistance decreased as the quantity of mixing air bubble increased. The image analysis showed that a spacing factor decreased and a specific surface area increased as the quantity of mixing air bubble increased.

Keywords: cellular sprayed concrete, silica fume, deviation, permeability

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317 Chaupadi Practice: A Cruel Discrimination against Women a Case Study of Achham District of Nepal

Authors: Santosh Thapa, Sankar Gurung

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Chaupadi is a tradition widely practiced in the far and mid-western region of Nepal. It is a practice where girls and women are not allowed to inter the house and touch the food, water and milk during their menstruation period of 4-7 days. They have to spend all the nights during the period in a specific hut (Chhaupadi Goth) which is a bit far from their residence where they faces various kinds of risk and violence like bullying, snakes and insect bite, wild animal attack etc. Sometimes the girls even do not go to school during their menstruation periods. After childbirth, the woman must stay in a cow shed for 11 days in such Chhaupadi practiced areas. This study limits the Achham district of the far western region which is the most vulnerable Chhaupadi practicing district. Several governmental and non-governmental organizations have been involving and spending huge amount of money for capacity building and awareness raising campaign for last 2 decades but still 9 out of 75 Village Development Committees (VDCs) have been partially practicing Chaupadi in the district. This study shows that the school attendance rate of the girls during the period have visibly increased which helps to increase the number of the girl graduation as well. Similarly, the practice of Chhaupadi is one of the reasons for increasing the number of cases of uterus prolapsus and poor reproductive health of women and girls. Triggering tools are the one of the best ways to accelerate the awareness campaign in the VDCs. This study recommends that the local bodies should coordinate and lead the overall awareness campaign program to sustain the Chaupadi free VDCs.

Keywords: awareness campaign, chaupadi practice, gender discrimination, violence

Procedia PDF Downloads 310
316 Synthesis of Montmorillonite/CuxCd1-xS Nanocomposites and Their Application to the Photodegradation of Methylene Blue

Authors: H. Boukhatem, L. Djouadi, H. Khalaf, R. M. Navarro, F. V. Ganzalez

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Synthetic organic dyes are used in various industries, such as textile industry, leather tanning industry, paper production, hair dye production, etc. Wastewaters containing these dyes may be harmful to the environment and living organisms. Therefore, it is very important to remove or degrade these dyes before discharging them into the environment. In addition to standard technologies for the degradation and/or removal of dyes, several new specific technologies, the so-called advanced oxidation processes (AOPs), have been developed to eliminate dangerous compounds from polluted waters. AOPs are all characterized by the same chemical feature: production of radicals (•OH) through a multistep process, although different reaction systems are used. These radicals show little selectivity of attack and are able to oxidize various organic pollutants due to their high oxidative capacity (reduction potential of HO• Eo = 2.8 V). Heterogeneous photocatalysis, as one of the AOPs, could be effective in the oxidation/degradation of organic dyes. A major advantage of using heterogeneous photocatalysis for this purpose is the total mineralization of organic dyes, which results in CO2, H2O and corresponding mineral acids. In this study, nanomaterials based on montmorillonite and CuxCd1-xS with different Cu concentration (0.3 < x < 0.7) were utilized for the degradation of the commercial cationic textile dye Methylene blue (MB), used as a model pollutant. The synthesized nanomaterials were characterized by fourier transform infrared (FTIR) and thermogravimetric-differential thermal analysis (TG–DTA). Test results of photocatalysis of methylene blue under UV-Visible irradiation show that the photoactivity of nanomaterials montmorillonite/ CuxCd1-xS increases with the increasing of Cu concentration. The kinetics of the degradation of the MB dye was described with the Langmuir–Hinshelwood (L–H) kinetic model.

Keywords: heterogeneous photocatalysis, methylene blue, montmorillonite, nanomaterial

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315 Coagulation-flocculation Process with Metal Salts, Synthetic Polymers and Biopolymers for the Removal of Trace Metals (Cu, Pb, Ni, Zn) from Wastewater

Authors: Andrew Hargreaves, Peter Vale, Jonathan Whelan, Carlos Constantino, Gabriela Dotro, Pablo Campo

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As a consequence of their potential to cause harm, there are strong regulatory drivers that require metals to be removed as part of the wastewater treatment process. Bioavailability-based standards have recently been specified for copper (Cu), lead (Pb), nickel (Ni) and zinc (Zn) and are expected to reduce acceptable metal concentrations. In order to comply with these standards, wastewater treatment works may require new treatment types to enhance metal removal and it is, therefore, important to examine potential treatment options. A substantial proportion of Cu, Pb, Ni and Zn in effluent is adsorbed to and/or complexed with macromolecules (eg. proteins, polysaccharides, aminosugars etc.) that are present in the colloidal size fraction. Therefore, technologies such as coagulation-flocculation (CF) that are capable of removing colloidal particles have good potential to enhance metals removal from wastewater. The present study investigated the effectiveness of CF at removing trace metals from humus effluent using the following coagulants; ferric chloride (FeCl3), the synthetic polymer polyethyleneimine (PEI), and the biopolymers chitosan and Tanfloc. Effluent samples were collected from a trickling filter treatment works operating in the UK. Using jar tests, the influence of coagulant dosage and the velocity and time of the slow mixing stage were studied. Chitosan and PEI had a limited effect on the removal of trace metals (<35%). FeCl3 removed 48% Cu, 56% Pb and 41% Zn at the recommended dose of 0.10 mg/L. At the recommended dose of 0.25 mg/L Tanfloc removed 77% Cu, 68% Pb, 18% Ni and 42% Zn. The dominant mechanism for particle removal by FeCl3 was enmeshment in the precipitates (i.e. sweep flocculation) whereas, for Tanfloc, inter-particle bridging was the dominant removal mechanism. Overall, FeCl3 and Tanfloc were found to be most effective at removing trace metals from wastewater.

Keywords: coagulation-flocculation, jar test, trace metals, wastewater

Procedia PDF Downloads 239
314 Opinion Mining to Extract Community Emotions on Covid-19 Immunization Possible Side Effects

Authors: Yahya Almurtadha, Mukhtar Ghaleb, Ahmed M. Shamsan Saleh

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The world witnessed a fierce attack from the Covid-19 virus, which affected public life socially, economically, healthily and psychologically. The world's governments tried to confront the pandemic by imposing a number of precautionary measures such as general closure, curfews and social distancing. Scientists have also made strenuous efforts to develop an effective vaccine to train the immune system to develop antibodies to combat the virus, thus reducing its symptoms and limiting its spread. Artificial intelligence, along with researchers and medical authorities, has accelerated the vaccine development process through big data processing and simulation. On the other hand, one of the most important negatives of the impact of Covid 19 was the state of anxiety and fear due to the blowout of rumors through social media, which prompted governments to try to reassure the public with the available means. This study aims to proposed using Sentiment Analysis (AKA Opinion Mining) and deep learning as efficient artificial intelligence techniques to work on retrieving the tweets of the public from Twitter and then analyze it automatically to extract their opinions, expression and feelings, negatively or positively, about the symptoms they may feel after vaccination. Sentiment analysis is characterized by its ability to access what the public post in social media within a record time and at a lower cost than traditional means such as questionnaires and interviews, not to mention the accuracy of the information as it comes from what the public expresses voluntarily.

Keywords: deep learning, opinion mining, natural language processing, sentiment analysis

Procedia PDF Downloads 171