Search results for: curing compound
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1330

Search results for: curing compound

310 Evaluation of a Chitin Synthesis Inhibitor Novaluron in the Shrimp Palaemon Adspersus: Impact on Ecdysteroids and Chitin Contents

Authors: Hinda Berghiche, Hamida Benradia, Noureddine Soltani

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Pesticides are widely used in crop production and are known to induce a major contamination of ecosystems especially in aquatic environments. The leaching of a large amount of pollutants derived from agricultural activities (fertilizers, pesticides) might contaminate rivers which diverse into the likes and estuarine and coastal environments affecting several organisms such as crustacean species. In this context, there is searched for new selective insecticides with minimal toxic effects on the environment and human health such as growth insect regulators (GIRs). The current study aimed to examine the impact of novaluron (CE 20%), a potent benzoylphenylurea derivative insecticide on mosquito larvae, against non-target shrimp, Palaemon adspersus (Decapoda, Palaemonidae). The compound was tested at two concentrations (0.91 mg/L and 4.30 mg/L) corresponding respectively to the LC50 and LC90 determined against fourth-instar larvae of Culiseta longiareolata (Diptera, Culicidae). The molting hormone titer was determined in the haemolymph by an enzyme-immunoassay, while chitin was measured in peripheral integument at different stages during the molting cycle. Under normal conditions, the haemolymphatic ecdysteroid concentrations increased during the molting cycle to reach peak at stage D. In the treated series, we note absence of the peak at stage D and an increase at stages B, C and D as compared to the controls. Concerning the chitin amounts, we observe an increase from stage A to stage C followed by a decrease at stage D. Exposition of shrimps to novaluron resulted in a significant decrease of values at all molting stages with a dose-response effect. Thus, the insecticide can present secondary effects on this non-target arthropod species.

Keywords: toxicology, novaluron, crustacean, palaemon adspersus, ecdysteroids, cuticle, chitin

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309 Antioxidant and Cytotoxic Effects of Different Extracts of Fruit Peels Against Three Cancer Cell Lines

Authors: Emad A. Shalaby

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Cancer is a disease that causes abnormal cell proliferation and invades nearby tissues. Lung cancer is the second most frequent cancer worldwide. Natural anti-cancer drugs have been developed with low side effects and toxicity. Citrus peels and extracts have been demonstrated to have significant pharmacological and physiological effects as a result of the high concentration of phenolic compounds found in citrus fruits, particularly peels. Tangerine peels can serve as an effective source of bioactive substances such as phenolics, flavonoids, and catechins, which have antioxidant, antibacterial, anticancer, and anti-inflammatory properties. Consequently, this work aims to determine the anticancer activity of ethanol extract of Tangerine peels against the A549 cell line and identify the phenolic compound profile (19 compounds) by using HPLC. Anticancer and antioxidant potentials of the extract were evaluated by MTT assay and TLC- TLC-bioautography sprayed with DPPH reagent, respectively. The obtained results revealed that tangerine peel extract showed significant activity against the A549 cell line with IC50 of 97.66 μg/mL. HPLC analysis proved that the highest concentration is naringenin 464.05 mg/g. More studies indicate that naringenin has significant anticancer potential on A549 cancer cells. The results showed that naringenin binds t0 EGFR protein in A549 with high binding affinity and thus may reduce lung cancer cell migration and enhance the apoptosis of cancer cells. From the obtained results it could be concluded that tangerine peel extract is an effective anti-cancer agent that may potentially serve as a natural therapeutic option for lung cancer treatment.

Keywords: tangerine peel, A549 cell line, anticancer, naringenin, HPLC analysis, naringenin, TLC bioautography

Procedia PDF Downloads 33
308 Production of Bricks Using Mill Waste and Tyre Crumbs at a Low Temperature by Alkali-Activation

Authors: Zipeng Zhang, Yat C. Wong, Arul Arulrajah

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Since automobiles became widely popular around the early 20th century, end-of-life tyres have been one of the major types of waste humans encounter. Every minute, there are considerable quantities of tyres being disposed of around the world. Most end-of-life tyres are simply landfilled or simply stockpiled, other than recycling. To address the potential issues caused by tyre waste, incorporating it into construction materials can be a possibility. This research investigated the viability of manufacturing bricks using mill waste and tyre crumb by alkali-activation at a relatively low temperature. The mill waste was extracted from a brick factory located in Melbourne, Australia, and the tyre crumbs were supplied by a local recycling company. As the main precursor, the mill waste was activated by the alkaline solution, which was comprised of sodium hydroxide (8m) and sodium silicate (liquid). The introduction ratio of alkaline solution (relative to the solid weight) and the weight ratio between sodium hydroxide and sodium silicate was fixed at 20 wt.% and 1:1, respectively. The tyre crumb was introduced to substitute part of the mill waste at four ratios by weight, namely 0, 5, 10 and 15%. The mixture of mill waste and tyre crumbs were firstly dry-mixed for 2 min to ensure the homogeneity, followed by a 2.5-min wet mixing after adding the solution. The ready mixture subsequently was press-moulded into blocks with the size of 109 mm in length, 112.5 mm in width and 76 mm in height. The blocks were cured at 50°C with 95% relative humidity for 2 days, followed by a 110°C oven-curing for 1 day. All the samples were then placed under the ambient environment until the age of 7 and 28 days for testing. A series of tests were conducted to evaluate the linear shrinkage, compressive strength and water absorption of the samples. In addition, the microstructure of the samples was examined via the scanning electron microscope (SEM) test. The results showed the highest compressive strength was 17.6 MPa, found in the 28-day-old group using 5 wt.% tyre crumbs. Such strength has been able to satisfy the requirement of ASTM C67. However, the increasing addition of tyre crumb weakened the compressive strength of samples. Apart from the strength, the linear shrinkage and water absorption of all the groups can meet the requirements of the standard. It is worth noting that the use of tyre crumbs tended to decrease the shrinkage and even caused expansion when the tyre content was over 15 wt.%. The research also found that there was a significant reduction in compressive strength for the samples after water absorption tests. In conclusion, the tyre crumbs have the potential to be used as a filler material in brick manufacturing, but more research needs to be done to tackle the durability problem in the future.

Keywords: bricks, mill waste, tyre crumbs, waste recycling

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307 Stability Analysis of Green Coffee Export Markets of Ethiopia: Markov-Chain Analysis

Authors: Gabriel Woldu, Maria Sassi

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Coffee performs a pivotal role in Ethiopia's GDP, revenue, employment, domestic demand, and export earnings. Ethiopia's coffee production and exports show high variability in the amount of production and export earnings. Despite being the continent's fifth-largest coffee producer, Ethiopia has not developed its ability to shine as a major exporter in the globe's green coffee exports. Ethiopian coffee exports were not stable and had high volume and earnings fluctuations. The main aim of this study was to analyze the dynamics of the export of coffee variation to different importing nations using a first-order Markov Chain model. 14 years of time-series data has been used to examine the direction and structural change in the export of coffee. A compound annual growth rate (CAGR) was used to determine the annual growth rate in the coffee export quantity, value, and per-unit price over the study period. The major export markets for Ethiopian coffee were Germany, Japan, and the USA, which were more stable, while countries such as France, Italy, Belgium, and Saudi Arabia were less stable and had low retention rates for Ethiopian coffee. The study, therefore, recommends that Ethiopia should again revitalize its market to France, Italy, Belgium, and Saudi Arabia, as these countries are the major coffee-consuming countries in the world to boost its export stake to the global coffee markets in the future. In order to further enhance export stability, the Ethiopian Government and other stakeholders in the coffee sector should have to work on reducing the volatility of coffee output and exports in order to improve production and quality efficiency, so that stabilize markets as well as to make the product attractive and price competitive in the importing countries.

Keywords: coffee, CAGR, Markov chain, direction of trade, Ethiopia

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306 Conversion of Sweet Sorghum Bagasse to Sugars for Succinic Acid Production

Authors: Enlin Lo, Ioannis Dogaris, George Philippidis

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Succinic acid is a compound used for manufacturing lacquers, resins, and other coating chemicals. It is also used in the food and beverage industry as a flavor additive. It is predominantly manufactured from petrochemicals, but it can also be produced by fermentation of sugars from renewable feedstocks, such as plant biomass. Bio-based succinic acid has great potential in becoming a platform chemical (building block) for commodity and high-value chemicals. In this study, the production of bio-based succinic acid from sweet sorghum was investigated. Sweet sorghum has high fermentable sugar content and can be cultivated in a variety of climates. In order to avoid competition with food feedstocks, its non-edible ‘bagasse’ (the fiber part after extracting the juice) was targeted. Initially, various conditions of pretreating sweet sorghum bagasse (SSB) were studied in an effort to remove most of the non-fermentable components and expose the cellulosic fiber containing the fermentable sugars (glucose). Concentrated (83%) phosphoric acid was utilized at temperatures 50-80 oC for 30-60 min at various SSB loadings (10-15%), coupled with enzymatic hydrolysis using commercial cellulase (Ctec2, Novozymes) enzyme, to identify the conditions that lead to the highest glucose yields for subsequent fermentation to succinic acid. As the pretreatment temperature and duration increased, the bagasse color changed from light brown to dark brown-black, indicating decomposition, which ranged from 15% to 72%, while the theoretical glucose yield is 91%. With Minitab software statistical analysis, a model was built to identify the optimal pretreatment condition for maximum glucose released. The projected theoretical bio-based succinic acid production is 23g per 100g of SSB, which will be confirmed with fermentation experiments using the bacterium Actinobacillus succinogenes.

Keywords: biomass, cellulose, enzymatic hydrolysis, fermentation, pretreatment, succinic acid

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305 Luminescent Functionalized Graphene Oxide Based Sensitive Detection of Deadly Explosive TNP

Authors: Diptiman Dinda, Shyamal Kumar Saha

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In the 21st century, sensitive and selective detection of trace amounts of explosives has become a serious problem. Generally, nitro compound and its derivatives are being used worldwide to prepare different explosives. Recently, TNP (2, 4, 6 trinitrophenol) is the most commonly used constituent to prepare powerful explosives all over the world. It is even powerful than TNT or RDX. As explosives are electron deficient in nature, it is very difficult to detect one separately from a mixture. Again, due to its tremendous water solubility, detection of TNP in presence of other explosives from water is very challenging. Simple instrumentation, cost-effective, fast and high sensitivity make fluorescence based optical sensing a grand success compared to other techniques. Graphene oxide (GO), with large no of epoxy grps, incorporate localized nonradiative electron-hole centres on its surface to give very weak fluorescence. In this work, GO is functionalized with 2, 6-diamino pyridine to remove those epoxy grps. through SN2 reaction. This makes GO into a bright blue luminescent fluorophore (DAP/rGO) which shows an intense PL spectrum at ∼384 nm when excited at 309 nm wavelength. We have also characterized the material by FTIR, XPS, UV, XRD and Raman measurements. Using this as fluorophore, a large fluorescence quenching (96%) is observed after addition of only 200 µL of 1 mM TNP in water solution. Other nitro explosives give very moderate PL quenching compared to TNP. Such high selectivity is related to the operation of FRET mechanism from fluorophore to TNP during this PL quenching experiment. TCSPC measurement also reveals that the lifetime of DAP/rGO drastically decreases from 3.7 to 1.9 ns after addition of TNP. Our material is also quite sensitive to 125 ppb level of TNP. Finally, we believe that this graphene based luminescent material will emerge a new class of sensing materials to detect trace amounts of explosives from aqueous solution.

Keywords: graphene, functionalization, fluorescence quenching, FRET, nitroexplosive detection

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304 Curcumin Reduces the Expression of Main Fibrogenic Genes and Phosphorylation of Smad3C Signaling Pathway in TGFB-Activated Human HSCs. A New Remedy for Liver Fibrosis

Authors: Elham Shakerian, Reza Afarin

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The hepatic disease causes approximately 2 million deaths/year worldwide. Liver fibrosis is the last stage of numerous chronic liver diseases, and until now there is no definite cure or drug for it. Activation of hepatic stellate cells (HSCs) is the main reason for fibrosis. Transforming growth factor (TGF-β), as a main profibrogenic cytokine, if increased in these cells, leads to liver fibrosis through smad3 signaling pathways and increasing the expressions of Collagen type I and III, and actin-alpha smooth muscle (αSMA) genes. Curcumin (CUR) is a polyphenolic compound and an active ingredient derived from the rhizome of the turmeric plant that exerts effective antioxidant, anti-inflammatory, and antimicrobial activity. It has been shown that daily consumption of curcumin may have a protective effect on the liver against oxidative stress associated with alcohol consumption. In this study, we investigate the role of Curcumin in decreasing HSC activation and treating liver fibrosis. First, the human HSCs were treated with 2 ng/ml of (TGF-β) for 24 hours to become activated, then with Silibinin for 24 hours. Total RNAs were extracted, reversely transcribed into cDNA, Quantitative Real-time PCR, and western blot were performed. The mRNA expression levels of Collagen type I and III, αSMA genes, and the level of smad3 phosphorylation in TGF-β activated human HSCs treated with Curcumin were significantly reduced compared to human HSCs untreated with Curcumin. Curcumin is effective in reducing the expression of fibrogenic genes in the activated human HSCs treated with TGFB through downregulation of the TGF-β/smad3 signaling pathway. Therefore, Curcumin possesses significant antifibrotic properties in hepatic fibrosis

Keywords: hepatic fibrosis, human HSCs, curcumin, fibrogenic genes

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303 The Chemical Composition and Larvicidal Activity of Essential Oils Derived from Piper Longepetiolatum and Piper Brachypetiolatum (Piperaceae) Against Aedes Aegypti Larvae (Culicidae) Were Investigated

Authors: Suelen C. Lima, André C. de Oliveira, Rosemary A. Roque

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Dengue is fatal arboviruses transmitted by the A. aegypti mosquito to more than 100 countries, for which the WHO estimates that 2.5 million people will be infected by these disease. The widespread of these diseases is due, among other factors, to the resistance that A. aegypti has to several commercial insecticides. On the other hand, natural products based on plants of the genus Piper (Piperaceae) are characterized by their insecticidal activities against mosquitoes. Piper longepetiolatum and Piper brachypetiolatum are species with wide distribution in the State of Amazonas. However, there is no investigation of phytochemical or biological of these plants against mosquitoes such as A. aegypti. The main of this study was to identify the chemical composition of the essential oil (EOs) from P. longepetiolatum and P. brachypetiolatum and to evaluate the biological activity against A. aegypti. The EOs were extracted by hydrodistillation from leaves (200 g) of P. longepetiolatum and P. brachypetiolatum and analyzed by GC-MS and GC-FID. The main compounds β-caryophyllene (99.9% of purity) and E-nerolidol (99.4% of purity) were purchased from Sigma-Aldrich® Brazil. The larvicidal activity of EOs (20 to 100 ppm), β-caryophyllene and E-nerolidol (10 to 50 ppm) was performed according to WHO protocol against A. aegypti larvae. The GC-MS and GC-FID analysis of EOs from P. longepetiolatum and P. brachypetiolatum indicated the majority presence of β-caryophyllene (35.42%) and E-nerolidol (49.79%), respectively. The results showed that all natural products presented larvicidal activity against A. aegypti. In this aspect, the OE from P. brachypetiolatum (LC50 of 15.51 ppm and LC90 of 22.79 ppm) was more active than the OE from P. longepetiolatum (LC50 of 47.17 ppm and LC90 of 69.60 ppm) (p < 0.05). Regarding of main compounds, E-nerolidol (LC50 of 9.50 ppm and LC90 of 23.89 ppm) showed higher larvicidal activity than the β-caryophyllene compound (LC50 of 79.00 ppm and LC90 of 230.91 ppm) (p < 0.05). The larvae treated with these natural products showed tremors and lethargic movements, suggesting that these natural products have neurotoxic action. These observations support studies to investigate the mechanism of action. This is the first record of the chemical composition and larvicidal activity of the EO from P. longepetiolatum and P. brachypetiolatum rich in β-caryophyllene and E-nerolidol against A. aegypti larvae.

Keywords: piperaceae, aedes, sesquiterpenes, biological control

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302 Phenolic Composition and Antioxidant Property of Honey with Dried Apricots

Authors: Jasna Čanadanović-Brunet, Gordana Ćetković, Sonja Djilas, Vesna Tumbas-Šaponjac, Jelena Vulić, Sladjana Stajčić

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Honey, produced by the honeybee, is a natural saturated sugar solution, which is mainly composed of a complex mixture of carbohydrates. Besides this, it also contains certain minor constituents, proteins, enzymes, amino and organic acids, lipids, vitamins, phenolic acids, flavonoids and carotenoids. Honey serves as a source of natural antioxidants, which are effective in reducing the risk of heart disease, cancer, immune-system decline, cataracts, and different inflammatory processes. Honey is consumed in its natural form alone, but also in combination with nuts and various kinds of dried fruits (plums, figs, cranberries, apricots etc.). The aim of this research was to investigate the contribution of dried apricot addition to polyphenols and flavonoids contents and antioxidant activities of honey. Some individual phenolic compounds in Serbian polyfloral honey (PH), linden honey (LH) and also in their mixtures with dried apricot, in 40% mass concentrations (PH40; LH40), were identified and quantified by HPLC. The most dominant phenolic compound was: gallic acid in LH (11.14 mg/100g), LH40 (42.65 mg/100g), PH (7.24 mg/100g) and catehin in PH40 (11.83 mg/100g). The antioxidant activity of PH, LH, PH40 and LH40 was tested by measuring their ability to scavenge hydroxyl radicals (OH) by electron spin resonance spectroscopy (ESR). Honey samples with 40% dried apricot exhibited better antioxidant activity measured by hydroxyl radical scavenging activity. The EC50 values, the amount of antioxidant necessary to decrease the initial concentration of OH radicals by 50%, were: EC50PH=3.36 mg/ml, EC50LH=13.36 mg/ml, EC50PH40=2.29 mg/ml, EC50 LH40=7.78 mg/ml. Our results indicate that supplementation of polyfloral honey and linden honey with dried apricots improves antioxidant activity of honey by enriching the phenolic composition.

Keywords: honey, dried apricot, HPLC, hydroxyl radical

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301 A Reflection on the Professional Development Journey of Science Educators

Authors: M. Shaheed Hartley

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Science and mathematics are regarded as gateway subjects in South Africa as they are the perceived route to careers in science, engineering, technology and mathematics (STEM). One of the biggest challenges that the country faces is the poor achievement of learners in these two learning areas in the external high school exit examination. To compound the problem many national and international benchmark tests paint a bleak picture of the state of science and mathematics in the country. In an attempt to address this challenge, the education department of the Eastern Cape Province invited the Science Learning Centre of the University of the Western Cape to provide training to their science teachers in the form of a structured course conducted on a part-time basis in 2010 and 2011. The course was directed at improving teachers’ content knowledge, pedagogical strategies and practical and experimental skills. A total of 41 of the original 50 science teachers completed the course and received their certificates in 2012. As part of their continuous professional development, 31 science teachers enrolled for BEd Hons in science education in 2013 and 28 of them completed the course in 2014. These students graduated in 2015. Of the 28 BEd Hons students who completed the course 23 registered in 2015 for Masters in Science Education and were joined by an additional 3 students. This paper provides a reflection by science educators on the training, supervision and mentorship provided to them as students of science education. The growth and development of students through their own reflection and understanding as well as through the eyes of the lecturers and supervisors that took part in the training provide the evaluation of the professional development process over the past few years. This study attempts to identify the merits, challenges and limitations of this project and the lessons to be learnt on such projects. It also documents some of the useful performance indicators with a view to developing a framework for good practice for such programmes.

Keywords: reflection, science education, professional development, rural schools

Procedia PDF Downloads 170
300 FWGE Production From Wheat Germ Using Co-culture of Saccharomyces cerevisiae and Lactobacillus plantarum

Authors: Valiollah Babaeipour, Mahdi Rahaie

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food supplements are rich in specific nutrients and bioactive compounds that eliminate free radicals and improve cellular metabolism. The major bioactive compounds are found in bran and cereal sprouts. Secondary metabolites of these microorganisms have antioxidant properties that can be used alone or in combination with chemotherapy and radiation therapy to treat cancer. Biologically active compounds such as benzoquinone derivatives extracted from fermented wheat germ extract (FWGE) have several positive effects on the overall state of human health and strengthen the immune system. The present work describes the discontinuous fermentation of raw wheat germ for FWGE production through the simultaneous culture process using the probiotic strains of Saccharomyces cerevisiae, Lactobacillus plantarum, and the possibility of using solid waste. To increase production efficiency, first to select important factors in the optimization of each fermentation process, using a factorial statistical scheme of stirring fraction (120 to 200 rpm), dilution of solids to solvent (1 to 8-12), fermentation time (16 to 24 hours) and strain to wheat germ ratio (20% to 50%) were studied and then simultaneous culture was performed to increase the yields of 2 and 6 dimethoxybenzoquinone (2,6-DMBQ). Since 2 and 6 dimethoxy benzoquinone were fermented as the main biologically active compound in wheat germ extract, UV-Vis analysis was performed to confirm the presence of 2 and 6 dimethoxy benzoquinone in the final product. In addition, 2,6-DMBQ of some products was isolated in a non-polar C-18 column and quantified using high performance liquid chromatography (HPLC). Based on our findings, it can be concluded that the increase of 2 and 6 dimethoxybenzoquinone in the simultaneous culture of Saccharomyces cerevisiae - Lactobacillus plantarum compared to pure culture of Saccharomyces cerevisiae (from 1.89 mg / g) to 28.9% (2.66 mg / g) Increased.

Keywords: wheat germ, FWGE, saccharomyces cerevisiae, lactobacillus plantarum, co-culture, 2, 6-DMBQ

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299 Modeling and Design of E-mode GaN High Electron Mobility Transistors

Authors: Samson Mil'shtein, Dhawal Asthana, Benjamin Sullivan

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The wide energy gap of GaN is the major parameter justifying the design and fabrication of high-power electronic components made of this material. However, the existence of a piezo-electrics in nature sheet charge at the AlGaN/GaN interface complicates the control of carrier injection into the intrinsic channel of GaN HEMTs (High Electron Mobility Transistors). As a result, most of the transistors created as R&D prototypes and all of the designs used for mass production are D-mode devices which introduce challenges in the design of integrated circuits. This research presents the design and modeling of an E-mode GaN HEMT with a very low turn-on voltage. The proposed device includes two critical elements allowing the transistor to achieve zero conductance across the channel when Vg = 0V. This is accomplished through the inclusion of an extremely thin, 2.5nm intrinsic Ga₀.₇₄Al₀.₂₆N spacer layer. The added spacer layer does not create piezoelectric strain but rather elastically follows the variations of the crystal structure of the adjacent GaN channel. The second important factor is the design of a gate metal with a high work function. The use of a metal gate with a work function (Ni in this research) greater than 5.3eV positioned on top of n-type doped (Nd=10¹⁷cm⁻³) Ga₀.₇₄Al₀.₂₆N creates the necessary built-in potential, which controls the injection of electrons into the intrinsic channel as the gate voltage is increased. The 5µm long transistor with a 0.18µm long gate and a channel width of 30µm operate at Vd=10V. At Vg =1V, the device reaches the maximum drain current of 0.6mA, which indicates a high current density. The presented device is operational at frequencies greater than 10GHz and exhibits a stable transconductance over the full range of operational gate voltages.

Keywords: compound semiconductors, device modeling, enhancement mode HEMT, gallium nitride

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298 Assessment of Biotic and Abiotic Water Factors of Antiao and Jiabong Rivers for Benthic Algae

Authors: Geno Paul S. Cumla, Jan Mariel M. Gentiles, M. Brenda Gajelan-Samson

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Eutrophication is a process where in there is a surplus of nutrients present in a lake or river. Harmful cyanobacteria, hypoxia, and primarily algae, which contain toxins, grow because of the excess nutrients. Algal blooms can cause fish kills, limiting the light penetration which reduces growth of aquatic organisms, causing die-offs of plants and produce conditions that are dangerous to aquatic and human life. The main cause for eutrophication is the presence of excessive amounts of phosphorus (P) and nitrogen (N). Nitrogen is necessary for the production of the plant tissues and is usually used to synthesize proteins. Nitrate is a compound that contains nitrogen, and at elevated levels it can cause harmful effects. Excessive amounts of phosphorus, displaced through human activity, is the major cause of algae growth and as well as degraded water quality. To accomplish this study the Assessment of Soluble inorganic nitrogen (SIN), Assessment of Soluble reactive phosphate (SRP), Determination of Chlorophyll a (Chl-a) concentration, and Determination of Dominating Taxa were done. The study addresses the high probability of algal blooms in Maqueda Bay by assessing the biotic and abiotic factors of Antiao and Jiabong rivers. The data predicts the overgrowth of algae and to create awareness to prevent the event from taking place. The study assesses the adverse effects that could be prevented by understanding and controlling algae. This should predict future cases of algal blooms and allow government agencies which require data to create programs to prevent and assess these issues.

Keywords: eutrophication, chlorophyll a, nitrogen, phosphorus, red tide, Kjeldahl method, spectrophotometer, assessment of soluble inorganic nitrogen, SIN, assessment of soluble reactive phosphate, SRP

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297 Strategic Shear Wall Arrangement in Buildings under Seismic Loads

Authors: Akram Khelaifia, Salah Guettala, Nesreddine Djafar Henni, Rachid Chebili

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Reinforced concrete shear walls are pivotal in protecting buildings from seismic forces by providing strength and stiffness. This study highlights the importance of strategically placing shear walls and optimizing the shear wall-to-floor area ratio in building design. Nonlinear analyses were conducted on an eight-story building situated in a high seismic zone, exploring various scenarios of shear wall positioning and ratios to floor area. Employing the performance-based seismic design (PBSD) approach, the study aims to meet acceptance criteria such as inter-story drift ratio and damage levels. The results indicate that concentrating shear walls in the middle of the structure during the design phase yields superior performance compared to peripheral distributions. Utilizing shear walls that fully infill the frame and adopting compound shapes (e.g., Box, U, and L) enhances reliability in terms of inter-story drift. Conversely, the absence of complete shear walls within the frame leads to decreased stiffness and degradation of shorter beams. Increasing the shear wall-to-floor area ratio in building design enhances structural rigidity and reliability regarding inter-story drift, facilitating the attainment of desired performance levels. The study suggests that a shear wall ratio of 1.0% is necessary to meet validation criteria for inter-story drift and structural damage, as exceeding this percentage leads to excessive performance levels, proving uneconomical as structural elements operate near the elastic range.

Keywords: nonlinear analyses, pushover analysis, shear wall, plastic hinge, performance level

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296 Mechanism of Modeling the Level of Bcr-Abl Oncoprotein by Ubiquitin-Proteasome System in Chronic Myeloid Leukemia

Authors: Svitlana Antonenko, Gennady Telegeev

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Introductive statement: The development of chronic myeloid leukemia (CML) is caused by Bcr-Abl oncoprotein. Modern treatments with tyrosine kinase inhibitors are greatly complicated by the mutational variability of the Bcr-Abl oncoprotein, which causes drug resistance. Therefore, there is an urgent need to develop new approaches to the treatment of the disease, which will allow modeling the level of Bcr-Abl oncoprotein in the cell. Promising in this direction is the identification of proteases that can selectively promote cellular proteolysis of oncoproteins. The aim of the study was to study the effect of the interaction of Bcr-Abl with deubiquitinase USP1 on the level of oncoprotein in CML cells. Methodology: K562 cells were selected for the experiment. Сells were incubated with ML323 inhibitor for 24 hours. Precipitation of endogenous proteins from K562 cell lysate was performed using anti-Bcr-Abl antibodies. Cell lysates and precipitation results were studied by Western blot. Subcellular localization of proteins was studied by immunofluorescence analysis followed by confocal microscopy. The results were analyzed quantitatively and statistically. Major findings: The Bcr-Abl/USP1 protein complex was detected in CML cells, and it was found that inhibition of USP1 deubiquitinating activity by the compound ML323 leads to disruption of this protein complex and a decrease in the level of Bcr-Abl oncoprotein in cells. The interaction of Bcr-Abl with USP1 may result in deubiquitination of the oncoprotein, which disrupts its proteasomal degradation and leads to the accumulation of CML in cells. Conclusion: We believe that the interaction of oncoprotein with USP1 may be one of the prerequisites that contribute to malignant cell transformation due to the deubiquitination of oncoprotein, which leads to its accumulation and disease progression. A correlation was found between the deubiquitinating activity of USP1 and the level of oncoprotein in CML cells. Thus, we identify deubiquitinase USP1 as a promising therapeutic target for the development of a new strategy for the treatment of CML by modulating the level of Bcr-Abl in the cell.

Keywords: chronic myeloid leukemia, Bcr-Abl, USP1, deubiquitination Bcr-Abl, K562 cell

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295 In Silico Exploration of Quinazoline Derivatives as EGFR Inhibitors for Lung Cancer: A Multi-Modal Approach Integrating QSAR-3D, ADMET, Molecular Docking, and Molecular Dynamics Analyses

Authors: Mohamed Moussaoui

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A series of thirty-one potential inhibitors targeting the epidermal growth factor receptor kinase (EGFR), derived from quinazoline, underwent 3D-QSAR analysis using CoMFA and CoMSIA methodologies. The training and test sets of quinazoline derivatives were utilized to construct and validate the QSAR models, respectively, with dataset alignment performed using the lowest energy conformer of the most active compound. The best-performing CoMFA and CoMSIA models demonstrated impressive determination coefficients, with R² values of 0.981 and 0.978, respectively, and Leave One Out cross-validation determination coefficients, Q², of 0.645 and 0.729, respectively. Furthermore, external validation using a test set of five compounds yielded predicted determination coefficients, R² test, of 0.929 and 0.909 for CoMFA and CoMSIA, respectively. Building upon these promising results, eighteen new compounds were designed and assessed for drug likeness and ADMET properties through in silico methods. Additionally, molecular docking studies were conducted to elucidate the binding interactions between the selected compounds and the enzyme. Detailed molecular dynamics simulations were performed to analyze the stability, conformational changes, and binding interactions of the quinazoline derivatives with the EGFR kinase. These simulations provided deeper insights into the dynamic behavior of the compounds within the active site. This comprehensive analysis enhances the understanding of quinazoline derivatives as potential anti-cancer agents and provides valuable insights for lead optimization in the early stages of drug discovery, particularly for developing highly potent anticancer therapeutics

Keywords: 3D-QSAR, CoMFA, CoMSIA, ADMET, molecular docking, quinazoline, molecular dynamic, egfr inhibitors, lung cancer, anticancer

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294 Development of Composite Materials for CO2 Reduction and Organic Compound Decomposition

Authors: H. F. Shi, C. L. Zhang

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Visible-light-responsive g-C3N4/NaNbO3 nanowires photocatalysts were fabricated by introducing polymeric g-C3N4 on NaNbO3 nanowires. The microscopic mechanisms of interface interaction, charge transfer and separation, as well as the influence on the photocatalytic activity of g-C3N4/NaNbO3 composite were systematic investigated. The HR-TEM revealed that an intimate interface between C3N4 and NaNbO3 nanowires formed in the g-C3N4/NaNbO3 heterojunctions. The photocatalytic performance of photocatalysts was evaluated for CO2 reduction under visible-light illumination. Significantly, the activity of g-C3N4/NaNbO3 composite photocatalyst for photoreduction of CO2 was higher than that of either single-phase g-C3N4 or NaNbO3. Such a remarkable enhancement of photocatalytic activity was mainly ascribed to the improved separation and transfer of photogenerated electron-hole pairs at the intimate interface of g-C3N4/NaNbO3 heterojunctions, which originated from the well-aligned overlapping band structures of C3N4 and NaNbO3. Pt loaded NaNbO3-xNx (Pt-NNON), a visible-light-sensitive photocatalyst, was synthesized by an in situ photodeposition method from H2PtCl6•6H2O onto NaNbO3-xNx (NNON) sample. Pt-NNON exhibited a much higher photocatalytic activity for gaseous 2-propanol (IPA) degradation under visible-light irradiation in contrast to NNON. The apparent quantum efficiency (AQE) of Pt-NNON sample for IPA photodegradation achieved up to 8.6% at the wavelength of 419 nm. The notably enhanced photocatalytic performance was attributed to the promoted charge separation and transfer capability in the Pt-NNON system. This work suggests that surface nanosteps possibly play an important role as an electron transfer at high way, which facilitates to the charge carrier collection onto Pt rich zones and thus suppresses recombination between photogenerated electrons and holes. This method can thus be considered as an excellent strategy to enhance photocatalytic activity of organic decomposition in addition to the commonly applied noble metal doping method.

Keywords: CO2 reduction, NaNbO3, nanowires, g-C3N4

Procedia PDF Downloads 179
293 Synthesis and Biological Activities of Novel -1,2,3-Triazoles Derivatives

Authors: Zahra Dehghani, Hoda Dehghani, Elham Zarenezhad

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1,2,3-Triazole derivatives are important compounds in medicinal chemistry owing to their wide applications in drug discovery. They can readily associate with biologically targets through the hydrogen bonding and dipole interactions. The 1,2,3-triazole core is a key structural motif in many bioactive compounds, exhibiting a broad spectrum of biological activities, such as antiviral, anticancer, anti-HIV, antibiotic, antibacterial, and antimicrobial. Additionally, they have found significant industrial applications as dyes, agrochemicals, corrosion inhibitors, photo stabilizers, and photographic materials. we disclose the synthesis and characterization of 1-azido-3-(aryl-2-yloxy)propan-2-ol drivatives. The chemistry works well with various ß-azido alcohols involving aryloxy, alkoxy and alkyl residues, and also tolerates a wide spectrum of electron-donating and electron-withdrawing functional groups in both alkyne and azide molecules. Most of ß-azidoalcohols used in these experiments were pre-synthesized by the regioselective ring opening reaction of corresponded epoxides with sodium azide, whereas the majority of terminal alkynes were prepared via SN2-type reaction of propargyl bromide and corresponded nucleophiles. To evaluate the bioactivity of title compounds, the in vitro antifungal activity of all compound was investigated against several pathogenic fungi including Candida albicans, Candida krusei, Aspergillus niger, and Trichophyton rubrum , clotrimazole and fluconazole was used as standard antifungal drugs, also To understand the antibacterial activity of synthesized compounds, they were in vitro screened against E. coli and S. aureus as Gram-negative and Gram-positive bacteria, respectively. The in vitro tests have shown the promising antifungal but marginal antibacterial activity against tested fungi and bacteria.

Keywords: biological activities, antibacterial, antifungal, 1, 2, 3-Triazole

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292 A New Approach for Preparation of Super Absorbent Polymers: In-Situ Surface Cross-Linking

Authors: Reyhan Özdoğan, Mithat Çelebi, Özgür Ceylan, Mehmet Arif Kaya

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Super absorbent polymers (SAPs) are defined as materials that can absorb huge amount of water or aqueous solution in comparison to their own mass and retain in their lightly cross-linked structure. SAPs were produced from water soluble monomers via polymerization subsequently controlled crosslinking. SAPs are generally used for water absorbing applications such as baby diapers, patient or elder pads and other hygienic product industries. Crosslinking density (CD) of SAP structure is an essential factor for water absortion capacity (WAC). Low internal CD leads to high WAC values and vice versa. However, SAPs have low CD and high swelling capacities and tend to disintegrate when pressure is applied upon them, so SAPs under load cannot absorb liquids effectively. In order to prevent this undesired situation and to obtain suitable SAP structures having high swelling capacity and ability to work under load, surface crosslinking can be the answer. In industry, these superabsorbent gels are mostly produced via solution polymerization and then they need to be dried, grinded, sized, post polymerized and finally surface croslinked (involves spraying of a crosslinking solution onto dried and grinded SAP particles, and then curing by heat). It can easily be seen that these steps are time consuming and should be handled carefully for the desired final product. If we could synthesize desired final SAPs using less processes it will help reducing time and production costs which are very important for any industries. In this study, synthesis of SAPs were achieved successfully by inverse suspension (Pickering type) polymerization and subsequently in-situ surface cross-linking via using proper surfactants in high boiling point solvents. Our one-pot synthesis of surface cross-linked SAPs invovles only one-step for preparation, thus it can be said that this technique exhibits more preferable characteristic for the industry in comparison to conventional methods due to its one-step easy process. Effects of different surface crosslinking agents onto properties of poly(acrylic acid-co-sodium acrylate) based SAPs are investigated. Surface crosslink degrees are evaluated by swelling under load (SUL) test. It was determined water absorption capacities of obtained SAPs decrease with the increasing surface crosslink density while their mechanic properties are improved.

Keywords: inverse suspension polymerization, polyacrylic acid, super absorbent polymers (SAPs), surface crosslinking, sodium polyacrylate

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291 Bioconversion of Capsaicin Using the Optimized Culture Broth of Lipase Producing Bacterium of Stenotrophomonas maltophilia

Authors: Doostishoar Farzad, Forootanfar Hamid, Hasan-Bikdashti Morvarid, Faramarzi Mohammad Ali, Ameri Atefe

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Introduction: Chili peppers and related plants in the family of capsaicum produce a mixture of capsaicins represent anticarcinogenic, antimutagenic, and chemopreventive properties. Vanillylamine, the main product of capsaicin hydrolysis is applied as a precursor for manufacturing of natural vanillin (a famous flavor). It is also used in the production of synthetic capsaicins harboring a wide variety of physiological and biological activities such as antibacterial and anti-inflammatory effects as well as enhancing of adrenal catecholamine secretion, analgesic, and antioxidative activities. The ability of some lipases, such as Novozym 677 BG and Novozym 435 and also some proteases e.g. trypsine and penicillin acylase, in capsaicin hydrolysis and green synthesis of vanillylamine has been investigated. In the present study the optimized culture broth of a newly isolated lipase-producing bacterial strain (Stenotrophomonas maltophilia) applied for the hydrolysis of capsaicin. Materials and methods: In order to compare hydrolytic activity of optimized and basal culture broth through capsaicin 2 mL of each culture broth (as sources of lipase) was introduced to capsaicin solution (500 mg/L) and then the reaction mixture (total volume of 3 mL) was incubated at 40 °C and 120 rpm. Samples were taken every 2 h and analyzed for vanillylamine formation using HPLC. Same reaction mixture containing boiled supernatant (to inactivate lipase) designed as blank and each experiment was done in triplicate. Results: 215 mg/L of vanillylamine was produced after the treatment of capsaicin using the optimized medium for 18 h, while only 61 mg/L of vanillylamine was detected in presence of the basal medium under the same conditions. No capsaicin conversion was observed in the blank sample, in which lipase activity was suppressed by boiling of the sample for 10 min. Conclusion: The application of optimized broth culture for the hydrolysis of capsaicin led to a 43% conversion of that pungent compound to vanillylamine.

Keywords: Capsaicin, green synthesis, lipase, stenotrophomonas maltophilia

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290 Practical Experiences in the Development of a Lab-Scale Process for the Production and Recovery of Fucoxanthin

Authors: Alma Gómez-Loredo, José González-Valdez, Jorge Benavides, Marco Rito-Palomares

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Fucoxanthin is a carotenoid that exerts multiple beneficial effects on human health, including antioxidant, anti-cancer, antidiabetic and anti-obesity activity; making the development of a whole process for its production and recovery an important contribution. In this work, the lab-scale production and purification of fucoxanthin in Isocrhysis galbana have been studied. In batch cultures, low light intensities (13.5 μmol/m2s) and bubble agitation were the best conditions for production of the carotenoid with product yields of up to 0.143 mg/g. After fucoxanthin ethanolic extraction from biomass and hexane partition, further recovery and purification of the carotenoid has been accomplished by means of alcohol – salt Aqueous Two-Phase System (ATPS) extraction followed by an ultrafiltration (UF) step. An ATPS comprised of ethanol and potassium phosphate (Volume Ratio (VR) =3; Tie-line Length (TLL) 60% w/w) presented a fucoxanthin recovery yield of 76.24 ± 1.60% among the studied systems and was able to remove 64.89 ± 2.64% of the carotenoid and chlorophyll pollutants. For UF, the addition of ethanol to the original recovered ethanolic ATPS stream to a final relation of 74.15% (w/w) resulted in a reduction of approximately 16% of the protein contents, increasing product purity with a recovery yield of about 63% of the compound in the permeate stream. Considering the production, extraction and primary recovery (ATPS and UF) steps, around a 45% global fucoxanthin recovery should be expected. Although other purification technologies, such as Centrifugal Partition Chromatography are able to obtain fucoxanthin recoveries of up to 83%, the process developed in the present work does not require large volumes of solvents or expensive equipment. Moreover, it has a potential for scale up to commercial scale and represents a cost-effective strategy when compared to traditional separation techniques like chromatography.

Keywords: aqueous two-phase systems, fucoxanthin, Isochrysis galbana, microalgae, ultrafiltration

Procedia PDF Downloads 396
289 Treatment of Histopathological Symptoms in N-Nitrosopyrrolidine Induced Changes in Lung Tissue by Isolated Flavonoid from Indigofera tinctoria

Authors: Aastha Agarwal, Veena Sharma

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N-nitrosopyrollidine or NPYR is a tobacco-specific nitrosamine which upon intoxicated causes abnormal production of Reactive Oxygen Species disrupt the endogenous antioxidant system. The study was designed to evaluate the histological changes in lung tissue of Mus musculus in NPYR administered lungs and effect of isolated flavonoid 3,6-dihydroxy-(3’,4’,7’-trimethoxyphenyl)-chromen-4-one-7-glucoside (ITC) from experimental plant Indigofera tinctorial. Post treatment with isolated compound significantly restored the abnormal symptoms and changes in pulmonary tissue. Transverse section of mouse lung in control animals appeared as a thin lace. Histologically, most of the lung was arranged as alveoli which were thin walled structures made up of single layered squamous epithelial cells. In the transverse section of lung at 100 X will clearly show the component of alveoli, surround by a thin layer of connective tissue and blood vessels. Smaller bronchioles were lined by cuboidal epithelial cells while larger bronchioles were lined by ciliated columnar epithelium layer while in NPYR intoxicated lungs signs of vast pulmonary damages and carcinogenesis as alveolar damage, necrosis, DADs or defused alveolar damages hyperplasia, metaplasia, dysplasia and next stage of carcinogenesis were revealed. Treatment with ITC showed the significant positive changes in the lung tissue due to the side hydroxyl and methoxy groups in its structure which help in combating oxidative injuries and give protection from the free radicals generated during the metabolism of NPYR in body. Thus, histopathological analysis confirms the development of the cancerous conditions in the lung tissue in mice model and the protective effects of ITC.

Keywords: flavonoid, histopathology, Indigofera tinctoria, lung

Procedia PDF Downloads 277
288 Optimization of Horticultural Crops by Using the Peats from Rawa Pening Lake as Soil Conditioner

Authors: Addharu Eri, Ningsih P. Lestari, Setyorini Adheliya, Syaiputri Khaidifah

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Rawa Pening is a lake at the Ambarawa Basin in Central Java, Indonesia. It serves as a source of power (hydroelectricity), irrigation, and flood control. The potential of this lake is getting worse by the presence of aquatic plants (Eichhornia crassipes) that grows wild, and it can make the lake covered by the cumulation of rotten E. crassipes. This cumulation causes the sediment formation which has high organic material composition. Sediment formation will be lead into a shallowing of the lake and affect water’s quality. The deposition of organic material produces methane gas and hydrogen sulfide, which in rain would turn the water muddy and decompose. Decomposition occuring in the water due to microbe activity in lake's water. The shallowing of Rawa Pening Lake not only will physically can reduce water discharge, but it also has ecologically major impact on water organism. The condition of Rawa Pening Lake peats can not be considered as unimportant issue. One of the solutions that can be applied is by using the peats as a compound materials on growing horticultural crops because the organic materials content on the mineral soil is low, particularly on an old soils. The horticultural crops required organic materials for growth promoting. The horticultural crops that use in this research is mustard cabbage (Brassica sp.). Using Rawa Pening's peats as the medium of plants with high organic materials that also can ameliorate soil’s physical properties, and indirectly serves as soil conditioner. Research will be focus on the peat’s contents and mustard cabbage product’s content. The contents that will be examined is the N-available, Ca, Mg, K, P, and C-organic. The analysis of Ca, Mg, and K is use soil base saturation measurement method and extracting soil is use NH4OAC solution. The aim of this study is to use the peats of Rawa Pening Lake as soil conditioner and increase the productivity of Brassica sp.

Keywords: Brassica sp., peats, rawa pening lake, soil conditioner

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287 Development of a Quick On-Site Pass/Fail Test for the Evaluation of Fresh Concrete Destined for Application as Exposed Concrete

Authors: Laura Kupers, Julie Piérard, Niki Cauberg

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The use of exposed concrete (sometimes referred to as architectural concrete), keeps gaining popularity. Exposed concrete has the advantage to combine the structural properties of concrete with an aesthetic finish. However, for a successful aesthetic finish, much attention needs to be paid to the execution (formwork, release agent, curing, weather conditions…), the concrete composition (choice of the raw materials and mix proportions) as well as to its fresh properties. For the latter, a simple on-site pass/fail test could halt the casting of concrete not suitable for architectural concrete and thus avoid expensive repairs later. When architects opt for an exposed concrete, they usually want a smooth, uniform and nearly blemish-free surface. For this choice, a standard ‘construction’ concrete does not suffice. An aesthetic surface finishing requires the concrete to contain a minimum content of fines to minimize the risk of segregation and to allow complete filling of more complex shaped formworks. The concrete may neither be too viscous as this makes it more difficult to compact and it increases the risk of blow holes blemishing the surface. On the other hand, too much bleeding may cause color differences on the concrete surface. An easy pass/fail test, which can be performed on the site just before the casting, could avoid these problems. In case the fresh concrete fails the test, the concrete can be rejected. Only in case the fresh concrete passes the test, the concrete would be cast. The pass/fail tests are intended for a concrete with a consistency class S4. Five tests were selected as possible onsite pass/fail test. Two of these tests already exist: the K-slump test (ASTM C1362) and the Bauer Filter Press Test. The remaining three tests were developed by the BBRI in order to test the segregation resistance of fresh concrete on site: the ‘dynamic sieve stability test’, the ‘inverted cone test’ and an adapted ‘visual stability index’ (VSI) for the slump and flow test. These tests were inspired by existing tests for self-compacting concrete, for which the segregation resistance is of great importance. The suitability of the fresh concrete mixtures was also tested by means of a laboratory reference test (resistance to segregation) and by visual inspection (blow holes, structure…) of small test walls. More than fifteen concrete mixtures of different quality were tested. The results of the pass/fail tests were compared with the results of this laboratory reference test and the test walls. The preliminary laboratory results indicate that concrete mixtures ‘suitable’ for placing as exposed concrete (containing sufficient fines, a balanced grading curve etc.) can be distinguished from ‘inferior’ concrete mixtures. Additional laboratory tests, as well as tests on site, will be conducted to confirm these preliminary results and to set appropriate pass/fail values.

Keywords: exposed concrete, testing fresh concrete, segregation resistance, bleeding, consistency

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286 Determination of Vinpocetine in Tablets with the Vinpocetine-Selective Electrode and Possibilities of Application in Pharmaceutical Analysis

Authors: Faisal A. Salih

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Vinpocetine (Vin) is an ethyl ester of apovincamic acid and is a semisynthetic derivative of vincamine, an alkaloid from plants of the genus Periwinkle (plant) vinca minor. It was found that this compound stimulates cerebral metabolism: it increases the uptake of glucose and oxygen, as well as the consumption of these substances by the brain tissue. Vinpocetine enhances the flow of blood in the brain and has a vasodilating, antihypertensive, and antiplatelet effect. Vinpocetine seems to improve the human ability to acquire new memories and restore memories that have been lost. This drug has been clinically used for the treatment of cerebrovascular disorders such as stroke and dementia memory disorders, as well as in ophthalmology and otorhinolaryngology. It has no side effects, and no toxicity has been reported when using vinpocetine for a long time. For the quantitative determination of Vin in dosage forms, the HPLC methods are generally used. A promising alternative is potentiometry with Vin- selective electrode, which does not require expensive equipment and materials. Another advantage of the potentiometric method is that the pills and solutions for injections can be used directly without separation from matrix components, which reduces both analysis time and cost. In this study, it was found that the choice of a good plasticizer an electrode with the following membrane composition: PVC (32.8 wt.%), ortho-nitrophenyl octyl ether (66.6 wt.%), tetrakis-4-chlorophenyl borate (0.6 wt.%) exhibits excellent analytical performance: lower detection limit (LDL) 1.2•10⁻⁷ M, linear response range (LRR) 1∙10⁻³–3.9∙10⁻⁶ M, the slope of the electrode function 56.2±0.2 mV/decade). Vin masses per average tablet weight determined by direct potentiometry (DP) and potentiometric titration (PT) methods for the two different sets of 10 tablets were (100.35±0.2–100.36±0.1) mg for two sets of blister packs. The mass fraction of Vin in individual tablets, determined using DP, was (9.87 ± 0.02–10.16 ±0.02) mg, while the RSD was (0.13–0.35%). The procedure has very good reproducibility, and excellent compliance with the declared amounts was observed.

Keywords: vinpocetine, potentiometry, ion selective electrode, pharmaceutical analysis

Procedia PDF Downloads 45
285 Environmental and Toxicological Impacts of Glyphosate with Its Formulating Adjuvant

Authors: I. Székács, Á. Fejes, S. Klátyik, E. Takács, D. Patkó, J. Pomóthy, M. Mörtl, R. Horváth, E. Madarász, B. Darvas, A. Székács

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Environmental and toxicological characteristics of formulated pesticides may substantially differ from those of their active ingredients or other components alone. This phenomenon is demonstrated in the case of the herbicide active ingredient glyphosate. Due to its extensive application, this active ingredient was found in surface and ground water samples collected in Békés County, Hungary, in the concentration range of 0.54–0.98 ng/ml. The occurrence of glyphosate appeared to be somewhat higher at areas under intensive agriculture, industrial activities and public road services, but the compound was detected at areas under organic (ecological) farming or natural grasslands, indicating environmental mobility. Increased toxicity of the formulated herbicide product Roundup, compared to that of glyphosate was observed on the indicator aquatic organism Daphnia magna Straus. Acute LC50 values of Roundup and its formulating adjuvant Polyethoxylated Tallowamine (POEA) exceeded 20 and 3.1 mg/ml, respectively, while that of glyphosate (as isopropyl salt) was found to be substantially lower (690-900 mg/ml) showing good agreement with literature data. Cytotoxicity of Roundup, POEA and glyphosate has been determined on the neuroectodermal cell line, NE-4C measured both by cell viability test and holographic microscopy. Acute toxicity (LC50) of Roundup, POEA and glyphosate on NE-4C cells was found to be 0.013±0.002%, 0.017±0.009% and 6.46±2.25%, respectively (in equivalents of diluted Roundup solution), corresponding to 0.022±0.003 and 53.1±18.5 mg/ml for POEA and glyphosate, respectively, indicating no statistical difference between Roundup and POEA and 2.5 orders of magnitude difference between these and glyphosate. The same order of cellular toxicity seen in average cell area has been indicated under quantitative cell visualization. The results indicate that toxicity of the formulated herbicide is caused by the formulating agent, but in some parameters toxicological synergy occurs between POEA and glyphosate.

Keywords: glyphosate, polyethoxylated tallowamine, Roundup, combined aquatic and cellular toxicity, synergy

Procedia PDF Downloads 293
284 Effects of α-IFN –SingleWalled Carbon NanoTube and α-IFN-PLGA Encapsulated on Breast Cancer in Rats Induced by DMBA by Using CA15-3 Tumor Marker

Authors: Anoosh Eghdami

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Background and aim: Conventional anticancer drugs display significant shortcomings which limit their use in cancer therapy. For this reason, important progress has been achieved in the field of nanotechnology to solve these problems and offer a promising and effective alternative for cancer treatment. Tumor markers may also be measured periodically during cancer therapy. Tumor markers may also be measured after treatment has ended to check for recurrence the return of cancer. The aim of this study was to evaluate the effect of nano drug delivery in induced breast cancer with DMBA by using CA15-3 tumor marker. Material and method: the rats were divided into five groups. The first group (control n=15) were fed only sesame oil as a gavage. In the second group n=15,10 mg DMBA was dissolved in 5ml of sesame oil and were fed as a gavage. In addition to DMBA treatment as the second group, in the 3,4and 5 groups after cancer creation, respectively affected by alpha interferon (α-IFN),alpha interferon conjugated with single walled carbon nano tube (α-IFN-SWNT) and encapsulated in poly lactic poly glycolic acid (α-IFN-PLGA). Tumor marker was measured in recent three groups. Results: The ANOVA test was used to determine the differences among the groups. Cancer inducing in rats (group 2) caused a significant increase in blood levels of CA15-3 (P<0.05). Administration of α-IFN, α-IFN –SWNT and α-IFN-PLGA in 3 groups of cancerous rats caused a significant decrease in blood levels of CA15-3 only the group that treated with α-IFN-PLGA (p<0.05). Conclusion: the results of this study indicate that nano drugs more effective than traditional drug in cancer treatment, although further work is needed to elucidate the safety and side effect of these compound in human.

Keywords: breast cancer, nano drug, tumor markers, CA15-3, α-IFN-PLGA, -IFN –SWNT

Procedia PDF Downloads 299
283 Study of Nanoclay Blends Based on PET/PEN Prepared by Reactive Extrusion

Authors: F. Zouai, F. Z. Benabid, S. Bouhelal, D. Benachour

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A new route of preparation of compatible blends, based on poly(ethylene terephthalate)(PET)/poly(ethylenenaphthalene2,6-dicarboxylate) (PEN)/clay nanocomposites has been successfully performed in one step by reactive melt extrusion. To achieve this, untreated clay was first purified and functionalized “in situ” with a compound based on an organic peroxide/sulfur mixture and (tetra methyl thiuram disulfide) TMTD as accelerator or activator for sulfur. The PET and PEN materials were first mixed separately in the melt state with different amounts of functionalized clay. It was observed that the compositions PET/4 wt% clay and PEN/7.5 wt% clay showed total exfoliation. These completely exfoliated compositions, called nPET and nPEN, respectively, were used to prepare new nPET/nPEN nanoblends in the same mixing batch. The nPET/nPEN nanoblends were compared to neat blends of PET/PEN. The blends and the nanocomposites were characterized by different techniques: differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS). The micro and nanostructure/properties relationships were investigated. The results of the WAXS measurements study showed that the exfoliation of tetrahedral nanolayers of clay was complete and the octahedral structure disappeared totally. From the different WAXS patterns, it is seen that all samples are amorphous phase. The thermal study showed that there are only one glass transition temperature Tg, one crystallization temperature Tc and one melting temperature Tm for every composition. This indicated that both PET/PEN blends and nPET/nPEN blends were compatible in the entire range of compositions. In addition, nPET/nPEN blends present lower Tc values and higher Tm values than the corresponding neat PET/PEN blends. The obtained results indicate that nPET/nPEN blends are somewhat different from the pure ones in nanostructure and behavior, thus showing the additional effect of nanolayers. The present study allowed establishing good correlations between the different measured properties.

Keywords: PET, PEN, montmorillonite, nanocomposites, exfoliation, reactive melt-mixing

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282 Physicochemical Characterization of Asphalt Ridge Froth Bitumen

Authors: Nader Nciri, Suil Song, Namho Kim, Namjun Cho

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Properties and compositions of bitumen and bitumen-derived liquids have significant influences on the selection of recovery, upgrading and refining processes. Optimal process conditions can often be directly related to these properties. The end uses of bitumen and bitumen products are thus related to their compositions. Because it is not possible to conduct a complete analysis of the molecular structure of bitumen, characterization must be made in other terms. The present paper focuses on physico-chemical analysis of two different types of bitumens. These bitumen samples were chosen based on: the original crude oil (sand oil and crude petroleum), and mode of process. The aim of this study is to determine both the manufacturing effect on chemical species and the chemical organization as a function of the type of bitumen sample. In order to obtain information on bitumen chemistry, elemental analysis (C, H, N, S, and O), heavy metal (Ni, V) concentrations, IATROSCAN chromatography (thin layer chromatography-flame ionization detection), FTIR spectroscopy, and 1H NMR spectroscopy have all been used. The characterization includes information about the major compound types (saturates, aromatics, resins and asphaltenes) which can be compared with similar data for other bitumens, more importantly, can be correlated with data from petroleum samples for which refining characteristics are known. Examination of Asphalt Ridge froth bitumen showed that it differed significantly from representative petroleum pitches, principally in their nonhydrocarbon content, heavy metal content and aromatic compounds. When possible, properties and composition were related to recovery and refining processes. This information is important because of the effects that composition has on recovery and processing reactions.

Keywords: froth bitumen, oil sand, asphalt ridge, petroleum pitch, thin layer chromatography-flame ionization detection, infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy

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281 Failure Analysis: Solid Rocket Motor Type “Candy” - Explosion in a Static Test

Authors: Diego Romero, Fabio Rojas, J. Alejandro Urrego

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The sounding rockets are aerospace vehicles that were developed in the mid-20th century, and Colombia has been involved in research that was carried out with the aim of innovating with this technology. The rockets are university research programs with the collaboration of the local government, with a simple strategy, develop and reduce the greatest costs associated with the production of a kind type of technology. In this way, in this document presents the failure analysis of a solid rocket motor, with the real compatibly to reach the thermosphere with a low-cost fuel. This solid rocket motor is the latest development of the Uniandes Aerospace Project (PUA for its Spanish acronym), an undergraduate and postgraduate research group at Universidad de los Andes (Bogotá, Colombia), dedicated to incurring in this type of technology. This motor has been carried out on Candy-type solid fuel, which is a compound of potassium nitrate and sorbitol, and the investigation has allowed the production of solid motors powerful enough to reach space, and which represents a unique technological advance in Latin America and an important development in experimental rocketry.To outline the main points the explosion in a static test is an important to explore and demonstrate the ways to develop technology, methodologies, production and manufacturing, being a solid rocket motor with 30 kN of thrust. In conclusion, this analysis explores different fields such as: design, manufacture, materials, production, first fire and more, with different engineering tools with principal objective find root failure. Following the engineering analysis methodology, was possible to design a new version of motor, with learned lessons new manufacturing specification, therefore, when publishing this project, it is intended to be a reference for future research in this field and benefit the industry.

Keywords: candy propellant, candy rockets, explosion, failure analysis, static test, solid rocket motor

Procedia PDF Downloads 141