Search results for: substrate intrinsic carrier concentration
Commenced in January 2007
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Edition: International
Paper Count: 6781

Search results for: substrate intrinsic carrier concentration

1351 Biosynthesis of Healthy Secondary Metabolites in Olive Fruit in Response to Different Agronomic Treatments

Authors: Anna Perrone, Federico Martinelli

Abstract:

Olive fruit is well-known for the high content in secondary metabolites with high interest at nutritional, nutraceutical, antioxidant, and healthy levels. The content of secondary metabolites in olive at harvest may be affected by different water regimes, with significant effects on olive oil composition and quality and, consequently, on its healthy and nutritional features. In this work, a summary of several research studies dealing with the biosynthesis of healthy and nutraceutical metabolites of the secondary metabolism in olive fruit will be reported. The phytochemical findings have been correlated with the expression of key genes involved in polyphenol, terpenoid, and carotenoid biosynthesis and metabolism in response to different development stages and water regimes. Flavonoids were highest in immature fruits, while anthocyanins increased at ripening. In epicarp tissue, this was clearly associated with an up-regulation of the UFGT gene. Olive fruits cultivated under different water regimes were analyzed by metabolomics. This method identified several hundred metabolites in the ripe mesocarp. Among them, 46 were differentially accumulated in the comparison between rain-fed and irrigated conditions. Well-known healthy metabolites were more abundant at a higher level of water regimes. Increased content of polyphenols was observed in the rain-fed fruit; particularly, anthocyanin concentration was higher at ripening. Several secondary metabolites were differentially accumulated between different irrigation conditions. These results showed that these metabolic approaches could be efficiently used to determine the effects of agronomic treatments on olive fruit physiology and, consequently, on nutritional and healthy properties of the obtained extra-virgin olive oil.

Keywords: olea europea, anthocyanins, polyphenols, water regimes

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1350 Renoprotective Effect of Alcoholic Extract of Bacopa monnieri via Inhibition of Advanced Glycation End Products and Oxidative Stress in Stz-Nicotinamide Induced Diabetic Nephropathy

Authors: Lalit Kishore, Randhir Singh

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Diabetic nephropathy (DN) is the major cause of morbidity among diabetic patients. In this study, the effect of Bacopa monnieri Linn. (Brahmi, BM), was studied in a Streptozotocin (STZ)-induced experimental rat model of DN. Diabetic nephropathy was induced in Male Wistar rats (body weight- 300± 10 gms) by single intra-peritoneal injection of STZ (45mg/kg, i.p.) after 15 min of Nicotinamide (230 mg/kg) administration. Different doses of alcoholic extract i.e. 100, 200 and 400 mg/kg was given for 45 days by oral gavage after induction of DN. Blood glucose level, serum insulin, glycosylated haemoglobin, renal parameters (serum urea, uric acid, creatinine and BUN) and lipid profile (total cholesterol, triglycerides, HDL, LDL and VLDL levels) were measured. Concentration of thiobarbituric acid reactive species (TBARS) and levels of antioxidant enzymes of reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) were evaluated in the kidney, liver and pancreas. At the end of treatment period the alcoholic extract of BM reduced the elevated level of blood glucose, serum insulin, renal parameters, lipid levels, TBARS, AGE’s in kidney and significantly increased body weight, HDL and antioxidant enzymes in dose dependent manner as compared to diabetic control animals. These results suggested the BM possesses significant renoprotective activity.

Keywords: AGE's, lipid profile, oxidative stress, renal parameters

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1349 Heavy Metal Adsorption from Synthetic Wastewater Using Agro Waste-Based Nanoparticles: A Comparative Study

Authors: Nomthandazo Precious Sibiya, Thembisile Patience Mahlangu, Sudesh Rathilal

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Heavy metal removal is critical in the wastewater treatment process due to its numerous harmful effects on human and aquatic life. There are several chemical and physical techniques for removing heavy metals from wastewater, including ion exchange, reverse osmosis, adsorption, electrodialysis, and ultrafiltration. However, adsorption technology has captivated researchers for years due to its low cost, high efficiency, and compatible with the environment. In this study, the adsorption effectiveness of three modified agro-waste materials was explored for the removal of lead from synthetic wastewater: banana peels (BP), orange peels (OP), and sugarcane bagasse (SB). The magnetite (Fe₃O₄) is incorporated with BP, OP, and SB at a ratio of 1:1 to create magnetic biosorbents. Characterization of biosorbents was carried out using and scanning electron microscopy (SEM) combined with energy-dispersive X-ray (EDX) to investigate surface morphology and elemental compositions, respectively. A series of batch experiments were carried out to investigate the effects of adsorbent mass, agitation time, and initial pH concentration on adsorption behaviour, as well as adsorption isotherms and kinetics. The removal efficiency of lead by the modified agro-waste materials proved to be superior to that of non-modified agro-waste materials. The proof of concept was achieved, and agro-waste materials can be paired with adsorption technology to effectively remove lead from aqueous media. The use of agricultural waste as biosorbents will aid in waste reduction and management.

Keywords: adsorption, isotherms, kinetics, agro waste, nanoparticles, batch

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1348 Effect of Feed Additive on Cryopreservation of Barki Ram Semen

Authors: Abdurzag Kerban, Mostfa M. Abou-Ahmed, Abdelrof M. Ghallab, Mona H. Shaker

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Preservation of semen had a major impact on sheep genetic breeding. The aim of this study was to evaluate the effect of protected fat, probiotic and zinc-enriched diets on semen freezability. Twenty two Barki rams were randomly assigned into four groups; Group I (n=5) was fed the basal diet enriched with 3.7% of dry fat/kg concentration/day, Group II (n=5) was fed a basal diet-enriched with 10gm of probiotic /head/day, Group III (n=6) was fed on the basal diet enriched with 100 ppm of 10% zinc chelated with methionine/kg dry matter/day and Group IV (n=6) was served as control. A pool of three to four ejaculates were pooled from rams within a period of ten weeks. Semen was diluted in egg yolk-Tris diluent and processed in 0.25 ml straw. Motility was evaluated after dilution, before freezing and post-thawing at 0, 1, 2 and 3 hour incubation. Viability index, acrosome integrity and leakage of intracellular enzymes (Aspartat aminotransferase and Alkline phosphatase) were also evaluated. Spermatozoa exhibited highly significant (P<0.01) percentages of motility at 0, 1, 2, and 3 hours incubation after thawing, viability index and acrosome integrity in rams fed a diet enriched with protected fat and zinc groups as compared with probiotic and control groups. Also, the mean value of extracellular leakage of AST was significantly lower in fat and zinc group as compared with probiotic and control groups. In conclusion, semen freezability was improved in animals fed a diet fortified with fat and zinc with no significant improvement in animals fed the probiotic-enriched diet.

Keywords: Barki ram semen, freezing, straw, feed additives

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1347 Eco-Friendly Approach in the Management of Stored Sorghum Insect Pests in Small-Scale Farmers’ Storage Structures of Northern Nigeria

Authors: Mohammed Suleiman, Ibrahim Sani, Samaila Abubakar, Kabir Abdullahi Bindawa

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Farmers’ storage structures in Pauwa village of Katsina State, Northern Nigeria, were simulated and incorporated with the application of leaf powders of Euphorbia balsamifera Aiton, Lawsonia inermis L., Mitracarpus hirtus (L.) DC. and Senna obtusifolia L. to search for more eco-friendly methods of managing insect pests of stored sorghum. The four most commonly grown sorghum varieties in the study area, namely “Farar Kaura” (FK), “Jar Kaura” (JK), “Yar Gidan Daudu” (YGD), and ICSV400 in threshed forms were used for the study. The four varieties (2.50 kg each) were packed in small polypropylene bags, mixed with the leaf powders at the concentration of 5% (w/w) of the plants, and kept in small stores of the aforementioned village for 12 weeks. Insect pests recovered after 12 weeks were Sitophilus zeamais, Rhyzopertha dominica, Tribolium castaneum, Cryptolestes ferrugineus, and Oryzaephilus surinamensis. There were significantly fewer insect pests in treated sorghum than in untreated types (p < 0.05). More weight losses were recorded in untreated grains than in those treated with the botanical powders. In terms of varieties, grain weight losses were in the order FK > JK > YGD > ICSV400. The botanicals also showed significant (p < 0.05) protectant ability against the weevils with their performance as E. balsamifera > L. inermis > M. hirtus > S. obtusifolia.

Keywords: botanical powders, infestations, insect pests, management, sorghum varieties, storage structures, weight losses

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1346 A Prediction Model for Dynamic Responses of Building from Earthquake Based on Evolutionary Learning

Authors: Kyu Jin Kim, Byung Kwan Oh, Hyo Seon Park

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The seismic responses-based structural health monitoring system has been performed to prevent seismic damage. Structural seismic damage of building is caused by the instantaneous stress concentration which is related with dynamic characteristic of earthquake. Meanwhile, seismic response analysis to estimate the dynamic responses of building demands significantly high computational cost. To prevent the failure of structural members from the characteristic of the earthquake and the significantly high computational cost for seismic response analysis, this paper presents an artificial neural network (ANN) based prediction model for dynamic responses of building considering specific time length. Through the measured dynamic responses, input and output node of the ANN are formed by the length of specific time, and adopted for the training. In the model, evolutionary radial basis function neural network (ERBFNN), that radial basis function network (RBFN) is integrated with evolutionary optimization algorithm to find variables in RBF, is implemented. The effectiveness of the proposed model is verified through an analytical study applying responses from dynamic analysis for multi-degree of freedom system to training data in ERBFNN.

Keywords: structural health monitoring, dynamic response, artificial neural network, radial basis function network, genetic algorithm

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1345 Triose Phosphate Utilisation at the (Sub)Foliar Scale Is Modulated by Whole-plant Source-sink Ratios and Nitrogen Budgets in Rice

Authors: Zhenxiang Zhou

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The triose phosphate utilisation (TPU) limitation to leaf photosynthesis is a biochemical process concerning the sub-foliar carbon sink-source (im)balance, in which photorespiration-associated amino acids exports provide an additional outlet for carbon and increases leaf photosynthetic rate. However, whether this process is regulated by whole-plant sink-source relations and nitrogen budgets remains unclear. We address this question by model analyses of gas-exchange data measured on leaves at three growth stages of rice plants grown at two-nitrogen levels, where three means (leaf-colour modification, adaxial vs abaxial measurements, and panicle pruning) were explored to alter source-sink ratios. Higher specific leaf nitrogen (SLN) resulted in higher rates of TPU and also led to the TPU limitation occurring at a lower intercellular CO2 concentration. Photorespiratory nitrogen assimilation was greater in higher-nitrogen leaves but became smaller in cases associated with yellower-leaf modification, abaxial measurement, or panicle pruning. The feedback inhibition of panicle pruning on rates of TPU was not always observed because panicle pruning blocked nitrogen remobilisation from leaves to grains, and the increased SLN masked the feedback inhibition. The (sub)foliar TPU limitation can be modulated by whole-plant source-sink ratios and nitrogen budgets during rice grain filling, suggesting a close link between sub-foliar and whole-plant sink limitations.

Keywords: triose phosphate utilization, sink limitation, panicle pruning, oryza sativa

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1344 Simulation and Controller Tunning in a Photo-Bioreactor Applying by Taguchi Method

Authors: Hosein Ghahremani, MohammadReza Khoshchehre, Pejman Hakemi

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This study involves numerical simulations of a vertical plate-type photo-bioreactor to investigate the performance of Microalgae Spirulina and Control and optimization of parameters for the digital controller by Taguchi method that MATLAB software and Qualitek-4 has been made. Since the addition of parameters such as temperature, dissolved carbon dioxide, biomass, and ... Some new physical parameters such as light intensity and physiological conditions like photosynthetic efficiency and light inhibitors are involved in biological processes, control is facing many challenges. Not only facilitate the commercial production photo-bioreactor Microalgae as feed for aquaculture and food supplements are efficient systems but also as a possible platform for the production of active molecules such as antibiotics or innovative anti-tumor agents, carbon dioxide removal and removal of heavy metals from wastewater is used. Digital controller is designed for controlling the light bioreactor until Microalgae growth rate and carbon dioxide concentration inside the bioreactor is investigated. The optimal values of the controller parameters of the S/N and ANOVA analysis software Qualitek-4 obtained With Reaction curve, Cohen-Con and Ziegler-Nichols method were compared. The sum of the squared error obtained for each of the control methods mentioned, the Taguchi method as the best method for controlling the light intensity was selected photo-bioreactor. This method compared to control methods listed the higher stability and a shorter interval to be answered.

Keywords: photo-bioreactor, control and optimization, Light intensity, Taguchi method

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1343 Tuning Nanomechanical Properties of Stimuli-Responsive Hydrogel Nanocomposite Thin Films for Biomedical Applications

Authors: Mallikarjunachari Gangapuram

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The design of stimuli-responsive hydrogel nanocomposite thin films is gaining significant attention in these days due to its wide variety of applications. Soft microrobots, drug delivery, biosensors, regenerative medicine, bacterial adhesion, energy storage and wound dressing are few advanced applications in different fields. In this research work, the nanomechanical properties of composite thin films of 20 microns were tuned by applying homogeneous external DC, and AC magnetic fields of magnitudes 0.05 T and 0.1 T. Polyvinyl alcohol (PVA) used as a matrix material and elliptical hematite nanoparticles (ratio of the length of the major axis to the length of the minor axis is 140.59 ± 1.072 nm/52.84 ± 1.072 nm) used as filler materials to prepare the nanocomposite thin films. Both quasi-static nanoindentation, Nano Dynamic Mechanical Analysis (Nano-DMA) tests were performed to characterize the viscoelastic properties of PVA, PVA+Hematite (0.1% wt, 2% wt and 4% wt) nanocomposites. Different properties such as storage modulus, loss modulus, hardness, and Er/H were carefully analyzed. The increase in storage modulus, hardness, Er/H and a decrease in loss modulus were observed with increasing concentration and DC magnetic field followed by AC magnetic field. Contact angle and ATR-FTIR experiments were conducted to understand the molecular mechanisms such as hydrogen bond formation, crosslinking density, and particle-particle interactions. This systematic study is helpful in design and modeling of magnetic responsive hydrogel nanocomposite thin films for biomedical applications.

Keywords: hematite, hydrogel, nanoindentation, nano-DMA

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1342 Morphological and Electrical Characterization of Polyacrylonitrile Nanofibers Synthesized Using Electrospinning Method for Electrical Application

Authors: Divyanka Sontakke, Arpit Thakre, D. K Shinde, Sujata Parmeshwaran

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Electrospinning is the most widely utilized method to create nanofibers because of the direct setup, the capacity to mass-deliver consistent nanofibers from different polymers, and the ability to produce ultrathin fibers with controllable diameters. Smooth and much arranged ultrafine Polyacrylonitrile (PAN) nanofibers with diameters going from submicron to nanometer were delivered utilizing Electrospinning technique. PAN powder was used as a precursor to prepare the solution utilized as a part of this process. At the point when the electrostatic repulsion contradicted surface tension, a charged stream of polymer solution was shot out from the head of the spinneret and along these lines ultrathin nonwoven fibers were created. The effect of electrospinning parameter such as applied voltage, feed rate, concentration of polymer solution and tip to collector distance on the morphology of electrospun PAN nanofibers were investigated. The nanofibers were heat treated for carbonization to examine the changes in properties and composition to make for electrical application. Scanning Electron Microscopy (SEM) was performed before and after carbonization to study electrical conductivity and morphological characterization. The SEM images have shown the uniform fiber diameter and no beads formation. The average diameter of the PAN fiber observed 365nm and 280nm for flat plat and rotating drum collector respectively. The four probe strategy was utilized to inspect the electrical conductivity of the nanofibers and the electrical conductivity is significantly improved with increase in oxidation temperature exposed.

Keywords: electrospinning, polyacrylonitrile carbon nanofibres, heat treatment, electrical conductivity

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1341 In vitro Inhibitory Action of an Aqueous Extract of Carob on the Release of Myeloperoxidase by Human Neutrophils

Authors: Kais Rtibi, Slimen Selmi, Jamel El-Benna, Lamjed Marzouki, Hichem Sebai

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Background: Myeloperoxidase (MPO) is a hemic enzyme found in high concentrations in the primary neutrophils granules. In addition to its peroxidase activity, it has a chlorination activity, using hydrogen peroxide and chloride ions to form hypochlorous acid, a strong oxidant, capable of chlorinating molecules. Bioactive compounds contained in medicinal plants could limit the action of this enzyme to reduce the reactive oxygen species production and its chlorination activity. The purpose of this study is to evaluate the effect of the carob aqueous extract (CAE) on the release of MPO by human neutrophils in vitro and its activity following stimulation of these cells by PMA. Methods: Neutrophils were isolated by simple sedimentation using the Dextran/Ficoll method. After stimulation with phorbol 12-myristate 13-acetate (PMA), neutrophils release the MPO by degranulation. The effect of CAE on the release of MPO was analyzed by the Western blot technique, while, its activity was determined by biochemical method using the method of 3,3', 5,5'- Tetramethylbenzidine (TMB) and hydrogen peroxide. The data were expressed as mean ± SEM. Results: The carob aqueous extract causes a decrease in MPO quantity and activity in a concentration-dependent manner which leads to a reduction of the production of the ROS (reactive oxygen species) and the protection of the molecules against oxidation and chlorination mechanisms. Conclusion: Thanks to its richness in bioactive compounds, the aqueous extract of carob could limit the development of damages related to the uncontrolled activity of MPO.

Keywords: carob, MPO, myeloperoxidase, neutrophils, PMA, phorbol 12-myristate 13-acetate

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1340 Effects of Drying Temperatures on the Qualitative and Quantitative Phytochemicals of Aqueous Extracts If the Calyces of Hibiscus Sabdariffa

Authors: John O. Efosa, S. Egielewa, M. A. Azeke

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Hibiscus sabdariffa (Hs) is known for its delicacy and also for medicinal properties. The flower calyces are usually sun- or oven-dried after harvesting. There are unverified claims that calyces dried at lower temperatures have better medicinal potentials than those dried at higher temperatures. The present work, therefore, aimed to study the effects of drying temperatures on the photochemical composition and antioxidant potential of aqueous extracts of the calyces of Hs. The calyces were dried at different temperatures (freeze-drying at -580C, drying at 300C, 400C, and 500 C.) respectively to constant weight. Samples (25 g) of dried calyces from each drying temperatures were weighed and placed in clean conical flasks and extracted; each was used for the analysis. Validated analytical assays were used for the determination of the different Phytochemicals. From the results obtained, it was observed that drying at 30°C resulted in the highest retention of total phenols, total flavonoids, tannins, alkaloids and saponins. Using the Inhibition Concentration values (IC50), some antioxidant parameters were found to follow the same trend as the earlier mentioned phytochemicals. Drying at 30°C resulted in the highest retention of DPPH Radical Scavenging Activity, Ferric Reducing Antioxidant Potential (FRAP), Nitrite radical scavenging Activity, 2, 2-azinobis-3-ethylbenzotiazoline-6-sulfonic acid (ABTS) radical scavenging activity There were, however, significant reductions in vitamin C and oxalate contents as the drying temperature increased (P < 0.05). From the results, it recommended that the calyces of Hibiscus sabdariffa be dried at 30°C in order to optimally elicit its medicinal potentials.

Keywords: antioxidant, drying temperature, hibiscus sabdariffa, phytochemicals, quantitative

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1339 Isolation and Identification Fibrinolytic Protease Endophytic Fungi from Hibiscus Leaves in Shah Alam

Authors: Mohd Sidek Ahmad, Zainon Mohd Noor, Zaidah Zainal Ariffin

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Fibrin degradation is an important part in prevention or treatment of intravascular thrombosis and cardiovascular diseases. Plasmin like fibrinolytic enzymes has given new hope to patient with cardiovascular diseases by treating fibrin aggregation related diseases with traditional plasminogen activator which have many side effects. Various researches involving wide range of sources for production of fibrinolytic proteases, from bacteria, fungi, insects and fermented foods. But few have looked into endophytic fungi as a potential source. Sixteen (16) endophytic fungi were isolated from Hibiscus sp. leaves from six different locations in Shah Alam, Selangor. Only two endophytic fungi, FH3 and S13 showed positive fibrinolytic protease activities. FH3 produced 5.78cm and S13 produced 4.48cm on Skim Milk Agar after 4 days of incubation at 27°C. Fibrinolytic activity was observed; 3.87cm and 1.82cm diameter clear zone on fibrin plate of FH3 and S13 respectively. 18srRNA was done for identification of the isolated fungi with positive fibrinolytic protease. S13 had the highest similarity (100%) to that of Penicillium citrinum strain TG2 and FH3 had the highest similarity (99%) to that of Fusarium sp. FW2PhC1, Fusarium sp. 13002, Fusarium sp. 08006, Fusarium equiseti strain Salicorn 8 and Fungal sp. FCASAn-2. Media composition variation showed the effects of carbon nitrogen on protein concentration, where the decrement of 50% of media composition caused drastic decrease in protease of FH3 from 1.081 to 0.056 and also S13 from 2.946 to 0.198.

Keywords: isolation, identification, fibrinolytic protease, endophytic fungi, Hibiscus leaves

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1338 Hydrogen Production Through Thermocatalytic Decomposition of Methane Over Biochar

Authors: Seyed Mohamad Rasool Mirkarimi, David Chiaramonti, Samir Bensaid

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Catalytic methane decomposition (CMD, reaction 4) is a one-step process for hydrogen production where carbon in the methane molecule is sequestered in the form of stable and higher-value carbon materials. Metallic catalysts and carbon-based catalysts are two major types of catalysts utilized for the CDM process. Although carbon-based catalysts have lower activity compared to metallic ones, they are less expensive and offer high thermal stability and strong resistance to chemical impurities such as sulfur. Also, it would require less costly separation methods as some of the carbon-based catalysts may not have an active metal component in them. Since the regeneration of metallic catalysts requires burning of the C on their surfaces, which emits CO/CO2, in some cases, using carbon-based catalysts would be recommended because regeneration can be completely avoided, and the catalyst can be directly used in other processes. This work focuses on the effect of biochar as a carbon-based catalyst for the conversion of methane into hydrogen and carbon. Biochar produced from the pyrolysis of poplar wood and activated biochar are used as catalysts for this process. In order to observe the impact of carbon-based catalysts on methane conversion, methane cracking in the absence and presence of catalysts for a gas stream with different levels of methane concentration should be performed. The results of these experiments prove conversion of methane in the absence of catalysts at 900 °C is negligible, whereas in the presence of biochar and activated biochar, significant growth has been observed. Comparing the results of the tests related to using char and activated char shows the enhancement obtained in BET surface area of the catalyst through activation leads to more than 10 vol.% methane conversion.

Keywords: hydrogen production, catalytic methane decomposition, biochar, activated biochar, carbon-based catalyts

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1337 Simulation of Climatic Change Effects on the Potential Fishing Zones of Dorado Fish (Coryphaena hippurus L.) in the Colombian Pacific under Scenarios RCP Using CMIP5 Model

Authors: Adriana Martínez-Arias, John Josephraj Selvaraj, Luis Octavio González-Salcedo

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In the Colombian Pacific, Dorado fish (Coryphaena hippurus L.) fisheries is of great commercial interest. However, its habitat and fisheries may be affected by climatic change especially by the actual increase in sea surface temperature. Hence, it is of interest to study the dynamics of these species fishing zones. In this study, we developed Artificial Neural Networks (ANN) models to predict Catch per Unit Effort (CPUE) as an indicator of species abundance. The model was based on four oceanographic variables (Chlorophyll a, Sea Surface Temperature, Sea Level Anomaly and Bathymetry) derived from satellite data. CPUE datasets for model training and cross-validation were obtained from logbooks of commercial fishing vessel. Sea surface Temperature for Colombian Pacific were projected under Representative Concentration Pathway (RCP) scenarios 4.5 and 8.5 using Coupled Model Intercomparison Project Phase 5 (CMIP5) and CPUE maps were created. Our results indicated that an increase in sea surface temperature reduces the potential fishing zones of this species in the Colombian Pacific. We conclude that ANN is a reliable tool for simulation of climate change effects on the potential fishing zones. This research opens a future agenda for other species that have been affected by climate change.

Keywords: climatic change, artificial neural networks, dorado fish, CPUE

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1336 Vitamin D Status in Tunisian Obese Patients

Authors: O. Berriche, R. Ben Othmen, H. Sfar, H. Abdesslam, S. Bou Meftah, S. Bhouri, F. Mahjoub, C. Amrouche, H. Jamoussi

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Introduction: Although current evidence emphasizes a high prevalence of vitamin D deficiency and an inverse association between serum 25-hydroxyvitamin D (25-OHD) concentration and obesity, no studies have been conducted in Tunisian obese. The objectives of our study were to estimate the vitamin D deficiency in obese, identify risk factors for vitamin D deficiency, demonstrating a possible association between vitamin D levels and metabolic parameters. Methods: This was a descriptive study of 100 obese 18-65 year-old. Anthropometric measurements were determined. Fasting blood samples were assessed for the following essays : serum calcium, 25 OH vitamin D, inorganic phosphorus, fasting glucose, HDL, LDL cholesterol and triglyceride. Insulin resistance was evaluated by fasting insulin, HOMA-IR and HOMA-ß. Consumption of foods riche in vitamin D, sunscreen use, wearing protective clothes and exposed surface were assessed through applied questionnaires. Results: The deficit of vitamin D (< 30 ng/ml) among obese was 98,8%. Half of them had a rate < 10ng/ml. Environmental factors involved in vitamin D deficiency are : the veil (p = 0,001), wearing protective clothes (p = 0,04) and the exposed surface (p = 0,011) and dietary factors are represented by the daily caloric intake (p = 0,0001). The percent of fat mass was negatively related to vitamin D levels (p = 0,01) but not with BMI (p = 0,11) or waist circumference (p = 0,88). Similarly, lipid and glucose profile had no link with vitamin D. We found no relationship between Insulin resistance and vitamin D levels. Conclusion: At the end of our study, we have identified a very important vitamin D deficiency among obese. Dosage and systematic supplementation should be applied and for that physician awareness is needed.

Keywords: insulinresistance, risk factors, obesity, vitamin D

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1335 White-Rot Fungi Phellinus as a Source of Antioxidant and Antitumor Agents

Authors: Yogesh Dalvi, Ruby Varghese, Nibu Varghese, C. K. Krishnan Nair

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Introduction: The Genus Phellinus, locally known as Phansomba is a well-known traditional folk medicine. Especially, in Western Ghats of India, many tribes use several species of Phellinus for various ailments related to teeth, throat, tongue, stomach and even wound healing. It is one of the few mushrooms which play a pivotal role in Ayurvedic Dravyaguna. Aim: The present study focuses on to investigate phytochemical analysis, antioxidant, and antitumor (in vitro and in vivo) potential of Phellinus robinae from South India, Kerala Material and Methods: The present study explores the following: 1. Phellinus samples were collected from Ranni, Pathanamthitta district of Kerala state, India from Artocarpus heterophyllus Lam. and species were identified using rDNA region. 2. The fruiting body was shadow dried, powdered and extracted with 50% alcohol using water bath at 60°C which was further condensed by rotary evaporator and lyophilized at minus 40°C temperature. 3. Secondary metabolites were analyzed by using various phytochemical screening assay (Hager’s Test, Wagner’s Test, Sodium hydroxide Test, Lead acetate Test, Ferric chloride Test, Folin-ciocalteu Test, Foaming Test, Benedict’s test, Fehling’s Test and Lowry’s Test). 4. Antioxidant and free radical scavenging activity were analyzed by DPPH, FRAP and Iron chelating assay. 5. The antitumor potential of Water alcohol extract of Phellinus (PAWE) is evaluated through In vitro condition by Trypan blue dye exclusion method in DLA cell line and In vivo by murine model. Result and Discussion: Preliminary phytochemical screening by various biochemical tests revealed presence of a variety of active secondary molecules like alkaloids, flavanoids, saponins, carbohydrate, protein and phenol. In DPPH and FRAP assay PAWE showed significantly higher antioxidant activity as compared to standard Ascorbic acid. While, in Iron chelating assay, PAWE exhibits similar antioxidant activity that of Butylated Hydroxytoluene (BHT) as standard. Further, in the in vitro study, PAWE showed significant inhibition on DLA cell proliferation in dose dependent manner and showed no toxicity on mice splenocytes, when compared to standard chemotherapy drug doxorubicin. In vivo study, oral administration of PAWE showed dose dependent tumor regression in mice and also raised the immunogenicity by restoring levels of antioxidant enzymes in liver and kidney tissue. In both in vitro and in vivo gene expression studies PAWE up-regulates pro-apoptotic genes (Bax, Caspases 3, 8 and 9) and down- regulates anti-apoptotic genes (Bcl2). PAWE also down regulates inflammatory gene (Cox-2) and angiogenic gene (VEGF). Conclusion: Preliminary phytochemical screening revealed that PAWE contains various secondary metabolites which contribute to its antioxidant and free radical scavenging property as evaluated by DPPH, FRAP and Iron chelating assay. PAWE exhibits anti-proliferative activity by the induction of apoptosis through a signaling cascade of death receptor-mediated extrinsic (Caspase8 and Tnf-α), as well as mitochondria-mediated intrinsic (caspase9) and caspase pathways (Caspase3, 8 and 9) and also by regressing angiogenic factor (VEGF) without any inflammation or adverse side effects. Hence, PAWE serve as a potential antioxidant and antitumor agent.

Keywords: antioxidant, antitumor, Dalton lymphoma ascites (DLA), fungi, Phellinus robinae

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1334 Climate Change in Awash River Basin of Ethiopia: A Projection Study Using Global and Regional Climate Model Simulations

Authors: Mahtsente Tadese, Lalit Kumar, Richard Koech

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The aim of this study was to project and analyze climate change in the Awash River Basin (ARB) using bias-corrected Global and Regional Climate Model simulations. The analysis included a baseline period from 1986-2005 and two future scenarios (the 2050s and 2070s) under two representative concentration pathways (RCP4.5 and RCP8.5). Bias correction methods were evaluated using graphical and statistical methods. Following the evaluation of bias correction methods, the Distribution Mapping (DM) and Power Transformation (PT) were used for temperature and precipitation projection, respectively. The 2050s and 2070s RCP4 simulations showed an increase in precipitation during half of the months with 32 and 10%, respectively. Moreover, the 2050s and 2070s RCP8.5 simulation indicated a decrease in precipitation with 18 and 26%, respectively. The 2050s and 2070s RCP8.5 simulation indicated a significant decrease in precipitation in four of the months (February/March to May) with the highest decreasing rate of 34.7%. The 2050s and 2070s RCP4.5 simulation showed an increase of 0.48-2.6 °C in maximum temperature. In the case of RCP8.5, the increase rate reached 3.4 °C and 4.1 °C in the 2050s and 2070s, respectively. The changes in precipitation and temperature might worsen the water stress, flood, and drought in ARB. Moreover, the critical focus should be given to mitigation strategies and management options to reduce the negative impact. The findings of this study provide valuable information on future precipitation and temperature change in ARB, which will help in the planning and design of sustainable mitigation approaches in the basin.

Keywords: variability, climate change, Awash River Basin, precipitation

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1333 Impact of Edible Coatings Made of Chitosan and Spray Dried Propolis in the Shell Life of White Cachama (Piaractus brachypomus)

Authors: David Guillermo Piedrahita Marquez, Hector Suarez Mahecha, Jairo Humberto Lopez

Abstract:

There is a need to preserve aquaculture matrices due to their high nutritional value, and its broad consumption, one of those species is the white cachama (Piaractus brachypomus), this fish is located in the rivers of eastern Colombia, and the previously mentioned species needs more study. Therefore, in a paper the effects of an alternative method of preservation of shell life were investigated, the method used is the application of an edible coating made from chitosan and ethanolic extract of propolis (EEP) encapsulated in maltodextrin. The coating was applied by immersion, and after that, we investigated the post mortem quality changes of the fish performing physicochemical and microbiological analysis. pH, volatile bases, test thiobarbituric acid and peroxide value were tested; finally, we studied the effect of the coating on mesophilic strains, coliforms and other microorganisms such as Staphylococcus, and Salmonella. Finally, we concluded that the coating prolongs the shelf life because it acts as a barrier to oxygen and moisture, the bioactive compounds trap free radicals and the coatings changes the metabolism and cause the cell lysis of the microorganisms. It was determined that the concentration of malonaldehyde, the volatile basic nitrogen content and pH are the variables that distinguish more clearly between the samples with the treatment and the control samples.

Keywords: antimicrobial activity, lipid oxidation, texture profile analysis (TPA), sensorial analysis, peroxide value, thiobarbituric acid assay (TBA), total volatile basic nitrogen (TVB-N)

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1332 Impact of Agriculture on the Groundwater Quality: Case of the Alluvial Plain of Nil River (North-Eastern Algerian)

Authors: S. Benessam, T. H. Debieche, A. Drouiche, F. Zahi, S. Mahdid

Abstract:

The intensive use of the chemical fertilizers and the pesticides in agriculture often produces a contamination of the groundwater by organic pollutants. The irrigation and/or rainwater transport the pollutants towards groundwater or water surface. Among these pollutants, one finds the nitrogen, often observed in the agricultural zones in the nitrate form. In order to understand the form and chemical mobility of nitrogen in groundwater, this study was conducted. A two-monthly monitoring of the parameters physicochemical and chemistry of water of the alluvial plain of Nil river (North-eastern Algerian) were carried out during the period from November 2013 to January 2015 as well as an in-situ investigation of the various chemical products used by the farmers. The results show a raise concentration of nitrates in the wells (depth < 20 m) of the plain, which the concentrations arrive at 50 mg/L (standard of potable water). On the other hand in drillings (depth > 20 m), one observes two behaviors. The first in the upstream part, where the aquifer is unconfined and the medium is oxidizing, one observes the weak nitrate concentrations, indicating its absorption by the ground during the infiltration of water towards the groundwater. The second in the central and downstream parts, where the groundwater is locally confined and the reducing medium, one observes an absence of nitrates and the appearance of nitrites and ammonium, indicating the reduction of nitrates. The projection of the analyses on diagrams Eh-pH of nitrogen has enabled to us to determine the intervals of variation of the nitrogen forms. This study also highlighted the effect of the rains, the pumping and the nature of the geological formations in the form and the mobility of nitrogen in the plain.

Keywords: groundwater, nitrogen, mobility, speciation

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1331 Inhibitory Effect of P2Y1R Agonist 1-Indolinoalkyl 2-Phenolic Derivative on Prostate Cancer Cell Proliferation via the MAPK Signalling

Authors: Hien Thi Thu Le, Nuno Rafael Candeias, Olli Yli-Harja, Meenakshisundaram Kandhavelu

Abstract:

Purinergic receptor 1 (P2Y1R) is the potential therapeutic target for inducing prostate cancer (PCa) cell death. Recently, 1-indolinoalkyl 2-phenolic derivative, HIC, was identified as a P2Y1R agonist that increases apoptosis and inhibits cell proliferation of PCa. However, the biological effects of HIC have not been extensively studied at the molecular level. In the present study, we have investigated the anticancer effects of HIC and the molecular mechanisms underlying in PCa cells. Half maximal inhibitory concentration (IC₅₀) of HIC was measured as 15.98 μM and 15.64 μM for DU145 and PC3 cells, respectively. In addition, we found that HIC inhibited cell growth and metastasis of PC3 and DU145 cells colonies, spheroid areas, and migrated cells. RNA seq analysis revealed significant changes of over 3000 genes (p value < 0.05) upon HIC treatment in PC3 and DU145 cells. Genes involved in DNA damage, apoptosis, cell cycle arrest at G1/S phase were modulated by HIC treatment. MAPK and NF-κB protein array revealed the increased expression of ERK1/2, JNK1/2, p53 phosphorylation, and p53 protein. ERK1/2 and JNK1/2 activations are known to increase the stabilization of p53, a tumor suppressor protein, which is required to arrest the cell cycle at G1/S phase and cause cell death of PCa cells. Overall, our results suggest that HIC can serve as a multi-dimensional chemotherapeutic agent possessing strong cytotoxic, anti-cancer, and anti-metastasis against PCa growth.

Keywords: prostate cancer, P2Y1 receptor, apoptosis, metastasis

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1330 Nature-based Solutions for Mitigating the Impact of Climate Change on Plants: Utilizing Encapsulated Plant Growth Regulators and Associative Microorganisms

Authors: Raana Babadi Fathipour

Abstract:

Over the past decades, the climatic CO2 concentration and worldwide normal temperature have been expanding, and this drift is anticipated to before long gotten to be more extreme. This situation of climate alter escalate abiotic stretch components (such as dry spell, flooding, saltiness, and bright radiation) that debilitate timberland and related environments as well as trim generation. These variables can contrarily influence plant development and advancement with a ensuing lessening in plant biomass aggregation and surrender, in expansion to expanding plant defenselessness to biotic stresses. As of late, biostimulants have ended up a hotspot as an viable and economical elective to reduce the negative impacts of stresses on plants. In any case, the larger part of biostimulants has destitute solidness beneath natural conditions, which leads to untimely debasement, shortening their organic movement. To unravel these bottlenecks, small scale- and nano-based definitions containing biostimulant atoms and/or microorganisms are picking up consideration as they illustrate a few points of interest over their routine details. In this survey, we center on the embodiment of plant development controllers and plant acquainted microorganisms as a technique to boost their application for plant assurance against abiotic stresses. We moreover address the potential restrictions and challenges confronted for the execution of this innovation, as well as conceivable outcomes with respect to future inquire about.

Keywords: bio stimulants, Seed priming, nano biotechnology, plant growth-promoting, rhizobacteria, plant growth regulators, microencapsulation

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1329 Air Quality Assessment for a Hot-Spot Station by Neural Network Modelling of the near-Traffic Emission-Immission Interaction

Authors: Tim Steinhaus, Christian Beidl

Abstract:

Urban air quality and climate protection are two major challenges for future mobility systems. Despite the steady reduction of pollutant emissions from vehicles over past decades, local immission load within cities partially still reaches heights, which are considered hazardous to human health. Although traffic-related emissions account for a major part of the overall urban pollution, modeling the exact interaction remains challenging. In this paper, a novel approach for the determination of the emission-immission interaction on the basis of neural network modeling for traffic induced NO2-immission load within a near-traffic hot-spot scenario is presented. In a detailed sensitivity analysis, the significance of relevant influencing variables on the prevailing NO2 concentration is initially analyzed. Based on this, the generation process of the model is described, in which not only environmental influences but also the vehicle fleet composition including its associated segment- and certification-specific real driving emission factors are derived and used as input quantities. The validity of this approach, which has been presented in the past, is re-examined in this paper using updated data on vehicle emissions and recent immission measurement data. Within the framework of a final scenario analysis, the future development of the immission load is forecast for different developments in the vehicle fleet composition. It is shown that immission levels of less than half of today’s yearly average limit values are technically feasible in hot-spot situations.

Keywords: air quality, emission, emission-immission-interaction, immission, NO2, zero impact

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1328 Antifungal Activity of Medicinal Plants Used Traditionally for the Treatment of Fungal Infections and Related Ailments in South Africa

Authors: T. C. Machaba, S. M. Mahlo

Abstract:

The current study investigates the antifungal properties of crude plant extracts from selected medicinal plant species. Eight plant species used by the traditional healers and local people to treat fungal infections were selected for further phytochemical analysis and biological assay. The selected plant species were extracted with solvent of various polarities such as acetone, methanol, ethanol, hexane, dichloromethane, ethyl acetate and water. Leaf, roots and bark extracts of Maerua juncea Pax, Albuca seineri (Engl & K. Krause) J.C Manning & Goldblatt, Senna italica Mill., Elephantorrhiza elephantina (Burch.) Skeels, Indigofera circinata Benth., Schinus molle L., Asparagus buchananii Bak., were screened for antifungal activity against three animal fungal pathogens (Candida albicans, Aspergillus fumigatus and Cryptococcus neoformans). All plant extracts were active against the tested microorganisms. Acetone, dichloromethane, hexane and ethanol extracts of Senna italica and Elephantorrhiza elephantine had excellent activity against Candida albicans and A. fumigatus with the lowest MIC value of 0.02 mg/ml. Bioautography assay was used to determine the number of antifungal compounds presence in the plant extracts. No active compounds were observed in plant extracts of Indigofera circinnata, Schinus molle and Pentarrhinum insipidum with good antifungal activity against C. albicans and A. fumigatus indicating possible synergism between separated metabolites.

Keywords: antifungal activity, bioautography, ethnobotanical survey, minimum inhibitory concentration

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1327 Effect of Eight Weeks Aerobic Training with Purslane Seeds on Peroxidant and Antioxidants Indicators in Women with Type2 Diabetes

Authors: Shima Dehghan

Abstract:

Aim: imbalance between antioxidant defensive system and increasing production of free radicals caused oxidative stress that can be rolled in cellular damage and occurring some of diseases such as diabetes. The aim of current study was to investigate the effect of eight weeks aerobic training on peroxidant and antioxidants indicators in women with type2 diabetes. Methodology: thirty two inactive women with type 2 diabetes were randomly assigned into four groups: 1. control, 2. Aerobic training, 3. Purslane seed and 4. Aerobic training + Purslane seed groups. Subjects were asked to accomplish eight weeks aerobic training (50 min aerobic exercise, 3 days/week, for to achieve 65-75% maximum of heart rate). Also, subjects in certain groups received purslane seeds for eight weeks. Blood samples were obtained in two sets (one session and after 8 weeks). Data was analyzed using one way ANOVA. A significant difference was accepted at p < 0/05 level. Results: After eight weeks of aerobic training with purslane seeds supplementation, malon dyaldehyde (MDA) concentration in training group were significantly decreased (p < 0/000), but A difference significant was not found in control group. Superoxide dismutase (SOD) and catalase (CAT) concentrations in training group were significantly increased (p < 0/000), while difference significant wasnot found in control group. Conclusion: The finding of the current study indicates that disciplined aerobic training with purslane seeds supplementation can be caused improvement in peroxidant/antioxidant balance in women with type2 diabetes.

Keywords: aerobic training, purslane seed, peroxidant/antioxidant balance, diabetes2

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1326 Emulsified Oil Removal in Produced Water by Graphite-Based Adsorbents Using Adsorption Coupled with Electrochemical Regeneration

Authors: Zohreh Fallah, Edward P. L. Roberts

Abstract:

One of the big challenges for produced water treatment is removing oil from water in the form of emulsified droplets which are not easily separated. An attractive approach is adsorption, as it is a simple and effective process. However, adsorbents must be regenerated in order to make the process cost effective. Several sorbents have been tested for treating oily wastewater. However, some issues such as high energy consumption for activated carbon thermal regeneration have been reported. Due to their significant electrical conductivity, Graphite Intercalation Compounds (GIC) were found to be suitable to be regenerated electrochemically. They are non-porous materials with low surface area and fast adsorptive capacity which are useful for removal of low concentration of organics. An innovative adsorption/regeneration process has been developed at the University of Manchester in which adsorption of organics are done by using a patented GIC adsorbent coupled with subsequent electrochemical regeneration. The oxidation of adsorbed organics enables 100% regeneration so that the adsorbent can be reused over multiple adsorption cycles. GIC adsorbents are capable of removing a wide range of organics and pollutants; however, no comparable report is available for removal of emulsified oil in produced water using abovementioned process. In this study the performance of this technology for the removal of emulsified oil in wastewater was evaluated. Batch experiments were carried out to determine the adsorption kinetics and equilibrium isotherm for both real produced water and model emulsions. The amount of oil in wastewater was measured by using the toluene extraction/fluorescence analysis before and after adsorption and electrochemical regeneration cycles. It was found that oil in water emulsion could be successfully treated by the treatment process and More than 70% of oil was removed.

Keywords: adsorption, electrochemical regeneration, emulsified oil, produced water

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1325 Aerobic Exercise Increases Circulating Hematopoietic Stem Cells and Endothelial Progenitor Cells

Authors: Khaled A. shady, Fagr B. Bazeed, Nashwa K. Abousamra, Ihab H. Elberawe, Ashraf E. shaalan, Mohamed A. Sobh

Abstract:

Physical activity activates a variety of adult stem cells which might be released into the circulation or might be activated in their organ-resident state. A variety of stimuli such as metabolic, mechanical, and hormonal stimuli might by responsible for the mobilization. This study was done to know the changes in hematopoietic stem cells and endothelial progenitor in athletes in the 24 hours following 30 min of aerobic exercise. Methods: Ten healthy male's athlete's (age 20.7± 0.61 y) performed moderate running with 30 min at 80% of velocity of The IAT. Blood samples taken pre-, and immediately, 30 min, 2h, 6h and 24h post-exercise were analyzed for hematopoietic stem cells (HSCs ), endothelial progenitor cells (EPCs(, vascular endothelial growth factor (VEGF), nitric oxide (NO), lactic acid (LA), and white blood cells . HSCs and EPCs were quantified by flow cytometry. Results: After 30min of aerobic exercise significant increases in HSCs, EPC, VEGF, NO, LA and WBCs (p ˂ 0.05). This increase will be at different rates according to the timing of taking blood sample and was in the maximum rate of increase after 30 min of aerobic exercise. HSCs, EPC, NO and WBCs were in the maximum rate of increase 2h post exercise. In addition, VEGF was in the maximum rate of increase immediately post exercise and LA concentration not affected after exercise. Conclusion: These data suggest that HSCs and EPCs increased after aerobic exercise due to increase of VEGF which play an important role in mobilization of stem cells and promotes NO increase which contributes to increase EPCs.

Keywords: physical activity, hematopoietic stem cells, mobilization, athletes

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1324 Green approach of Anticorrosion Coating of Steel Based on Polybenzoxazine/Henna Nanocomposites

Authors: Salwa M. Elmesallamy, Ahmed A. Farag, Magd M. Badr, Dalia S. Fathy, Ahmed Bakry, Mona A. El-Etre

Abstract:

The term green environment is an international trend. It is become imperative to treat the corrosion of steel with a green coating to protect the environment. From the potential adverse effects of the traditional materials.A series of polybenzoxazine/henna composites (PBZ/henna), with different weight percent (3,5, and 7 wt % (of henna), were prepared for corrosion protection of carbon steel. The structures of the prepared composites were verified using FTIR analysis. The mechanical properties of the resins, such as adhesion, hardness, binding, and tensile strength, were also measured. It was found that the tensile strength increases by henna loading up to 25% higher than the tidy resin. The thermal stability was investigated by thermogravimetric analysis (TGA) the loading of lawsone (henna) molecules into the PBZ matrix increases the thermal stability of the composite. UV stability was tested by the UV weathering accelerator to examine the possibility that henna can also act as an aging UV stabilizer. The effect of henna content on the corrosion resistance of composite coatings was tested using potentiostatic polarization and electrochemical spectroscopy. The presence of henna in the coating matrix enhances the protection efficiency of polybenzoxazine coats. Increasing henna concentration increases the protection efficiency of composites. The quantum chemical calculations for polybenzoxazine/henna composites have resulted that the highest corrosion inhibition efficiency, has the highest EHOMO and lowest ELUMO; which is in good agreement with results obtained from experiments.

Keywords: polybenzoxazine, corrosion, green chemistry, carbon steel

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1323 Established Novel Approach for Chemical Oxygen Demand Concentrations Measurement Based Mach-Zehner Interferometer Sensor

Authors: Su Sin Chong, Abdul Aziz Abdul Raman, Sulaiman Wadi Harun, Hamzah Arof

Abstract:

Chemical Oxygen Demand (COD) plays a vital role determination of an appropriate strategy for wastewater treatment including the control of the quality of an effluent. In this study, a new sensing method was introduced for the first time and developed to investigate chemical oxygen demand (COD) using a Mach-Zehner Interferometer (MZI)-based dye sensor. The sensor is constructed by bridging two single mode fibres (SMF1 and SMF2) with a short section (~20 mm) of multimode fibre (MMF) and was formed by tapering the MMF to generate evanescent field which is sensitive to perturbation of sensing medium. When the COD concentration increase takes effect will induce changes in output intensity and effective refractive index between the microfiber and the sensing medium. The adequacy of decisions based on COD values relies on the quality of the measurements. Therefore, the dual output response can be applied to the analytical procedure enhance measurement quality. This work presents a detailed assessment of the determination of COD values in synthetic wastewaters. Detailed models of the measurement performance, including sensitivity, reversibility, stability, and uncertainty were successfully validated by proficiency tests where supported on sound and objective criteria. Comparison of the standard method with the new proposed method was also conducted. This proposed sensor is compact, reliable and feasible to investigate the COD value.

Keywords: chemical oxygen demand, environmental sensing, Mach-Zehnder interferometer sensor, online monitoring

Procedia PDF Downloads 492
1322 Borrowing Performance: A Network Connectivity Analysis of Second-Tier Cities in Turkey

Authors: Eğinç Simay Ertürk, Ferhan Gezi̇ci̇

Abstract:

The decline of large cities and the rise of second-tier cities have been observed as a global trend with significant implications for economic development and urban planning. In this context, the concepts of agglomeration shadow and borrowed size have gained importance as network externalities that affect the growth and development of surrounding areas. Istanbul, Izmir, and Ankara are Turkey's most significant metropolitan cities and play a significant role in the country's economy. The surrounding cities rely on these metropolitan cities for economic growth and development. However, the concentration of resources and investment in a single location can lead to agglomeration shadows in the surrounding areas. On the other hand, network connectivity between metropolitan and second-tier cities can result in borrowed function and performance, enabling smaller cities to access resources, investment, and knowledge they would not otherwise have access. The study hypothesizes that the network connectivity between second-tier and metropolitan cities in Turkey enables second-tier cities to increase their urban performance by borrowing size through these networks. Regression analysis will be used to identify specific network connectivity parameters most strongly associated with urban performance. Network connectivity will be measured with parameters such as transportation nodes and telecommunications infrastructure, and urban performance will be measured with an index, including parameters such as employment, education, and industry entrepreneurship, with data at the province levels. The contribution of the study lies in its research on how networking can benefit second-tier cities in Turkey.

Keywords: network connectivity, borrowed size, agglomeration shadow, secondary cities

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