Search results for: concentration index
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8148

Search results for: concentration index

4578 Mutagenic in vitro Activity and Genotoxic Effect of Zygophyllum Cornutun Methanolic Extract

Authors: Awatif Boumaza, Abderraouf Hilali, Hayat Talbi, Houda Sbayou

Abstract:

The methanolic extract of Zygophyllum cornutun coss, an Algerian medicinal plant, was screened to the presence of mutagenic activity and genotoxic effect using the Ames test (Salmonella/microsome) and the micronucleus assay respectively. Positive results were obtained with both tests. The Ames test showed mutagenic activity in the presence of microsomal activation, while negative result was observed without microsomal activation. In the micronucleus test, two parameters were evaluated: the frequency of the micronucleus that increased in a dose dependent way and the proliferation index that decreased according to the micronucleus frequency. Even that further studies must be carried out, the mutagenic activity and the genotoxic effect of Zygophyllum cornutum should be taken in consideration when used as therapeutic plant.

Keywords: ames test, micronucleus test, mutagenic activity, genotoxicity, Zygophyllum cornutum

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4577 Commodity Price Shocks and Monetary Policy

Authors: Faisal Algosair

Abstract:

We examine the role of monetary policy in the presence of commodity price shocks using a Dynamic stochastic general equilibrium (DSGE) model with price and wage rigidities. The model characterizes a commodity exporter by its degree of export diversification, and explores the following monetary regimes: flexible domestic inflation targeting; flexible Consumer Price Index inflation targeting; exchange rate peg; and optimal rule. An increase in the degree of diversification is found to mitigate responses to commodity shocks. The welfare comparison suggests that a flexible exchange rate regime under the optimal rule is preferred to an exchange rate peg. However, monetary policy provides limited stabilization effects in an economy with low degree of export diversification.

Keywords: business cycle, commodity price, exchange rate, global financial cycle

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4576 Bioanalytical Method Development and Validation of Aminophylline in Rat Plasma Using Reverse Phase High Performance Liquid Chromatography: An Application to Preclinical Pharmacokinetics

Authors: S. G. Vasantharaju, Viswanath Guptha, Raghavendra Shetty

Abstract:

Introduction: Aminophylline is a methylxanthine derivative belonging to the class bronchodilator. From the literature survey, reported methods reveals the solid phase extraction and liquid liquid extraction which is highly variable, time consuming, costly and laborious analysis. Present work aims to develop a simple, highly sensitive, precise and accurate high-performance liquid chromatography method for the quantification of Aminophylline in rat plasma samples which can be utilized for preclinical studies. Method: Reverse Phase high-performance liquid chromatography method. Results: Selectivity: Aminophylline and the internal standard were well separated from the co-eluted components and there was no interference from the endogenous material at the retention time of analyte and the internal standard. The LLOQ measurable with acceptable accuracy and precision for the analyte was 0.5 µg/mL. Linearity: The developed and validated method is linear over the range of 0.5-40.0 µg/mL. The coefficient of determination was found to be greater than 0.9967, indicating the linearity of this method. Accuracy and precision: The accuracy and precision values for intra and inter day studies at low, medium and high quality control samples concentrations of aminophylline in the plasma were within the acceptable limits Extraction recovery: The method produced consistent extraction recovery at all 3 QC levels. The mean extraction recovery of aminophylline was 93.57 ± 1.28% while that of internal standard was 90.70 ± 1.30%. Stability: The results show that aminophylline is stable in rat plasma under the studied stability conditions and that it is also stable for about 30 days when stored at -80˚C. Pharmacokinetic studies: The method was successfully applied to the quantitative estimation of aminophylline rat plasma following its oral administration to rats. Discussion: Preclinical studies require a rapid and sensitive method for estimating the drug concentration in the rat plasma. The method described in our article includes a simple protein precipitation extraction technique with ultraviolet detection for quantification. The present method is simple and robust for fast high-throughput sample analysis with less analysis cost for analyzing aminophylline in biological samples. In this proposed method, no interfering peaks were observed at the elution times of aminophylline and the internal standard. The method also had sufficient selectivity, specificity, precision and accuracy over the concentration range of 0.5 - 40.0 µg/mL. An isocratic separation technique was used underlining the simplicity of the presented method.

Keywords: Aminophyllin, preclinical pharmacokinetics, rat plasma, RPHPLC

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4575 Static Analysis Deployment Model for Code Quality on Research and Development Projects of Software Development

Authors: Jeong-Hyun Park, Young-Sik Park, Hyo-Teag Jung

Abstract:

This paper presents static analysis deployment model for code quality on R&D Projects of SW Development. The proposed model includes the scope of R&D projects and index for static analysis of source code, operation model and execution process, environments and infrastructure system for R&D projects of SW development. There is the static analysis result of pilot project as case study based on the proposed deployment model and environment, and strategic considerations for success operation of the proposed static analysis deployment model for R&D Projects of SW Development. The proposed static analysis deployment model in this paper will be adapted and improved continuously for quality upgrade of R&D projects, and customer satisfaction of developed source codes and products.

Keywords: static analysis, code quality, coding rules, automation tool

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4574 Adsorption of a Pharmaceutical Pollutant on Activated Carbon of Orange Peels

Authors: Faroudja Mohellebi, Fayrouz Khalida Kies, Moncef Rezzik El Marhoun, Feriel Yahiat

Abstract:

The purpose of this study is to valorize an agro-food waste (orange peels) by its use as an adsorbent in the treatment of water loaded with pharmaceutical micropollutant present in aquatic environments, oxytetracycline. The tests, carried out in batch mode, made it possible to study the influence on the sorptive capacity of calcined orange peels of several parameters: the contact time, the initial concentration of oxytetracycline, the adsorbent dose, and the initial pH of the solution. The pseudo-second-order model is best adapted to represent the adsorption kinetics. The Langmuir model describes the adsorption isotherm of oxytetracycline. The adsorption is favored in a basic environment.

Keywords: adsorption, emerging pollutants, oxytetracycline, water treatment

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4573 Evaluation of the Pathogenicity Test of Some Entomopathogenic Fungus Isolates against Tomato Leaf Miner Tuta Absoluta (Meyrick) Larvae [Lepidoptera: Gelechiidae])

Authors: Tadesse Kebede, Orkun Baris Kovanci

Abstract:

Tomatoes leaf minor (Tutaabasoluta) is one of the most economically important insect pest in tomatoes production. The use of biological control such as entomopathogen fungi isolates would be a long-term and cost-effective solution to control insects pest. Therefore, identifying the most virulent and pathogenic entomopathogen fungi is one of the basic requirements for effective management options to combat Tomatoes leaf minor (Tutaabasoluta). Furthermore, the pathogenicity and virulence difference among entomopathogenfungus strains is not widely well investıgated. The current study was therefore initiated to test the pathogenicity of some entomopathogenic fungus isolates against Tutaabsoluta. The experiment was conducted at Bursa Uludag University, Agiculutre faculty, horticulture department glasshouse in 2020/2021. Tutabasoluta adult were collected, and masslarvae were reared in a growth chamber. Then, ten third instar larvae were inoculated with four entomopathogen fungi isolates (Beuaveriabassania Ak-10, Beuaveriabassania Ak-14, Metarhziumanisoplai Ak-11, and Metarhziumanisoplai Ak-12) with different inoculum suspension (0, 1x10⁶, 1x10⁷,,4 × 10⁸, 4× 10⁹ and 1×10¹⁰ conidia /ml) in a factorial experiment arranged in randomized complete block design with three replication. Mortality data assessment was done on the 3rd, 5thand 7th days after treatment and analyzed. The analysis of variance for mortality rate revealed significant variations (p<0.05) among entomoptahogen fungi isolates and conidia concentrations. The results revealed thatMetarhziumanisoplai Ak-12was found to show the lowest mortality percentage80.77%, highest LC50 2.3x108, and the longest incubation period, LT50, 4.9 and LT90, 9.9daysand considered to be less pathogenic fungi. On the other hand, Beuaveriabassania Ak-10 isolate showed the highest mortality percentage, 91%, and the lowest LT50, 4, and LT90, 7.6 values at 1×10¹⁰ conidia /ml, followed by Beuaveriabassania Ak-14 and being considered as the most aggressive bio-agent. Metarhziumanisoplai Ak-11 was determined as moderately virulent, having a mortality rate 27-81%. Results also revealed that among conidia concentrations, 1x10⁹ and 1x10¹⁰ suspensions is the most effective, while 1x10⁶ conidia/ml concentration is the least effective. Hence, results indicated that EPF tested were effective against T. absoluta larvae. As the current work revealed the potential variation among entomopathogen fungi isolates and concentration against third instar larvae.

Keywords: tuta absoluta, tomato, metarhizium anisopliae, beauveria bassiana, biological control

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4572 Theoretical Investigation of Electronic, Structural and Thermoelectric Properties of Mg₂SiSn (110) Surface

Authors: M. Ramesh, Manish K. Niranjan

Abstract:

The electronic, structural and thermoelectric properties of Mg₂SiSn (110) surface are investigated within the framework of first principle density functional theory and semi classical Boltzmann approach. In particular, directional dependent thermoelectric properties such as electrical conductivity, thermal conductivity, Seebeck coefficient and figure of merit are explored. The (110)-oriented Mg₂SiSn surface exhibits narrow indirect band gap of ~0.17 eV. The thermoelectric properties are found to be significant along the y-axis at 300 K and along x-axis at 500 K. The figure of merit (ZT) for hole carrier concentration is found to be significantly large having magnitude 0.83 (along x-axis) at 500 K and 0.26 (y-axis) at 300 K. Our results suggest that Mg₂SiSn (110) surface is promising for various thermoelectric applications due to its overall good thermoelectric properties.

Keywords: thermoelectric, surface science, semiconducting silicide, first principles calculations

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4571 Chemical Constituents of Silene Arenarioides Desf

Authors: Haba Hamada, Lavaud Cathrine, Benkhaled Mohammed

Abstract:

The Silene genus is the most representative of the caryophyllaceae family for their rich content in secondary metabolites; saponins, flavonoids and flavonoids glycosides, phytoecdysones, oligosaccharides have been isolated and identified. The Silene genus represented by about 700 species in the temrerate region of the word, the main concentration of spcies is Europe, Asia and North Africa. Three known compounds 1-3 were isolated from the aerial parts of Silene arenarioides Desf. by using different chromatographic methods. The structures of the isolated compounds were determined as stigmasterolglycoside, Soyacerebroside, maltol glycoside. The structures of the isolated compounds were determined by using the NMR (1H-NMR, 13C-NMR, COSY, HSQC, and HMBC) techniques and mass spectroscopy. The antimicrobial and antioxydant activities of the different extracts and compound have been reported.

Keywords: caryophyllaceae, flavonoids, saponosids, flavonoids glycosides

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4570 Health and Performance Fitness Assessment of Adolescents in Middle Income Schools in Lagos State

Authors: Onabajo Paul

Abstract:

The testing and assessment of physical fitness of school-aged adolescents in Nigeria has been going on for several decades. Originally, these tests strictly focused on identifying health and physical fitness status and comparing the results of adolescents with others. There is a considerable interest in health and performance fitness of adolescents in which results attained are compared with criteria representing positive health rather than simply on score comparisons with others. Despite the fact that physical education program is being studied in secondary schools and physical activities are encouraged, it is observed that regular assessment of students’ fitness level and health status seems to be scarce or not being done in these schools. The purpose of the study was to assess the heath and performance fitness of adolescents in middle-income schools in Lagos State. A total number of 150 students were selected using the simple random sampling technique. Participants were measured on hand grip strength, sit-up, pacer 20 meter shuttle run, standing long jump, weight and height. The data collected were analyzed with descriptive statistics of means, standard deviations, and range and compared with fitness norms. It was concluded that majority 111(74.0%) of the adolescents achieved the healthy fitness zone, 33(22.0%) were very lean, and 6(4.0%) needed improvement according to the normative standard of Body Mass Index test. For muscular strength, majority 78(52.0%) were weak, 66(44.0%) were normal, and 6(4.0%) were strong according to the normative standard of hand-grip strength test. For aerobic capacity fitness, majority 93(62.0%) needed improvement and were at health risk, 36(24.0%) achieved healthy fitness zone, and 21(14.0%) needed improvement according to the normative standard of PACER test. Majority 48(32.0%) of the participants had good hip flexibility, 38(25.3%) had fair status, 27(18.0%) needed improvement, 24(16.0%) had very good hip flexibility status, and 13(8.7%) of the participants had excellent status. Majority 61(40.7%) had average muscular endurance status, 30(20.0%) had poor status, 29(18.3%) had good status, 28(18.7%) had fair muscular endurance status, and 2(1.3%) of the participants had excellent status according to the normative standard of sit-up test. Majority 52(34.7%) had low jump ability fitness, 47(31.3%) had marginal fitness, 31(20.7%) had good fitness, and 20(13.3%) had high performance fitness according to the normative standard of standing long jump test. Based on the findings, it was concluded that majority of the adolescents had better Body Mass Index status, and performed well in both hip flexibility and muscular endurance tests. Whereas majority of the adolescents performed poorly in aerobic capacity test, muscular strength and jump ability test. It was recommended that to enhance wellness, adolescents should be involved in physical activities and recreation lasting 30 minutes three times a week. Schools should engage in fitness program for students on regular basis at both senior and junior classes so as to develop good cardio-respiratory, muscular fitness and improve overall health of the students.

Keywords: adolescents, health-related fitness, performance-related fitness, physical fitness

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4569 Bread-Making Properties of Rice Flour Dough Using Fatty Acid Salt

Authors: T. Hamaishi, Y. Morinaga, H. Morita

Abstract:

Introduction: Rice consumption in Japan has decreased, and Japanese government has recommended use of rice flour in order to expand the consumption of rice. There are two major protein components present in flour, called gliadin and glutenin. Gluten forms when water is added to flour and is mixed. As mixing continues, glutenin interacts with gliadin to form viscoelastic matrix of gluten. Rice flour bread does not expand as much as wheat flour bread. Because rice flour is not included gluten, it cannot construct gluten network in the dough. In recent years, some food additives have been used for dough-improving agent in bread making, especially surfactants has effect in order to improve dough extensibility. Therefore, we focused to fatty acid salt which is one of anionic surfactants. Fatty acid salt is a salt consist of fatty acid and alkali, it is main components of soap. According to JECFA(FAO/WHO Joint Expert Committee on Food Additives), salts of Myristic(C14), Palmitic(C16) and Stearic(C18) could be used as food additive. They have been evaluated ADI was not specified. In this study, we investigated to improving bread-making properties of rice flour dough adding fatty acid salt. Materials and methods: The sample of fatty acid salt is myristic (C14) dissolved in KOH solution to a concentration of 350 mM and pH 10.5. Rice dough was consisted of 100 g of flour using rice flour and wheat gluten, 5 g of sugar, 1.7 g of salt, 1.7g of dry yeast, 80 mL of water and fatty acid salt. Mixing was performed for 500 times by using hand. The concentration of C14K in the dough was 10 % relative to flour weight. Amount of gluten in the dough was 20 %, 30 % relative to flour weight. Dough expansion ability test was performed to measure physical property of bread dough according to the methods of Baker’s Yeast by Japan Yeast Industry Association. In this test, 150 g of dough was filled from bottom of the cylinder and fermented at 30 °C,85 % humidity for 120 min on an incubator. The height of the expansion in the dough was measured and determined its expansion ability. Results and Conclusion: Expansion ability of rice dough with gluten content of 20 %, 30% showed 316 mL, 341 mL for 120 min. When C14K adding to the rice dough, dough expansion abilities were 314 mL, 368 mL for 120 min, there was no significant difference. Conventionally it has been known that the rice flour dough contain gluten of 20 %. The considerable improvement of dough expansion ability was achieved when added C14K to wheat flour. The experimental result shows that c14k adding to the rice dough with gluten content more than 20 % was not improving bread-making properties. In conclusion, rice bread made with gluten content more than 20 % without C14K has been suggested to contribute to the formation of the sufficient gluten network.

Keywords: expansion ability, fatty acid salt, gluten, rice flour dough

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4568 Numerical Analysis of Heat Transfer Enhancement in Heat Exchangers by using Dimpled Tube

Authors: Bader Alhumaidi Alsubaei, Zahid H. Akash, Ali Imam Sunny

Abstract:

The heat transfer coefficient can be improved passively by using a dimpled surface on the tube. The contact area where heat transfer takes place can be enlarged and turbulence will be purposefully produced inside the duct; as a consequence, higher heat transfer quality will be achieved by employing an extended inner or outer surface (dimpled surface). In order to compare the rate and quality of heat transfer between a regular-shaped pipe and a dimpled pipe, a dimpled tube with a fixed dimple radius was created. Numerical analysis of the plain and dimpled pipes was performed using ANSYS. A 23% increase in Nusselt number was seen for dimpled tubes compared to plain tubes. In comparison to plain tubes, dimpled tubes' increase in thermal performance index was found to be between 8% and 10%. An increase in pressure drop of 18% was noted.

Keywords: heat transfer, dimpled tube, CFD, ANSYS

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4567 Unconfined Laminar Nanofluid Flow and Heat Transfer around a Square Cylinder with an Angle of Incidence

Authors: Rafik Bouakkaz

Abstract:

A finite-volume method simulation is used to investigate two dimensional unsteady flow of nanofluids and heat transfer characteristics past a square cylinder inclined with respect to the main flow in the laminar regime. The computations are carried out of nanoparticle volume fractions varying from 0 ≤ ∅ ≤ 5% for an inclination angle in the range 0° ≤ δ ≤ 45° at a Reynolds number of 100. The variation of stream line and isotherm patterns are presented for the above range of conditions. Also, it is noticed that the addition of nanoparticles enhances the heat transfer. Hence, the local Nusselt number is found to increase with increasing value of the concentration of nanoparticles for the fixed value of the inclination angle.

Keywords: copper nanoparticles, heat transfer, square cylinder, inclination angle

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4566 [Keynote Talk]: Monitoring of Ultrafine Particle Number and Size Distribution at One Urban Background Site in Leicester

Authors: Sarkawt M. Hama, Paul S. Monks, Rebecca L. Cordell

Abstract:

Within the Joaquin project, ultrafine particles (UFP) are continuously measured at one urban background site in Leicester. The main aims are to examine the temporal and seasonal variations in UFP number concentration and size distribution in an urban environment, and to try to assess the added value of continuous UFP measurements. In addition, relations of UFP with more commonly monitored pollutants such as black carbon (BC), nitrogen oxides (NOX), particulate matter (PM2.5), and the lung deposited surface area(LDSA) were evaluated. The effects of meteorological conditions, particularly wind speed and direction, and also temperature on the observed distribution of ultrafine particles will be detailed. The study presents the results from an experimental investigation into the particle number concentration size distribution of UFP, BC, and NOX with measurements taken at the Automatic Urban and Rural Network (AURN) monitoring site in Leicester. The monitoring was performed as part of the EU project JOAQUIN (Joint Air Quality Initiative) supported by the INTERREG IVB NWE program. The total number concentrations (TNC) were measured by a water-based condensation particle counter (W-CPC) (TSI model 3783), the particle number concentrations (PNC) and size distributions were measured by an ultrafine particle monitor (UFP TSI model 3031), the BC by MAAP (Thermo-5012), the NOX by NO-NO2-NOx monitor (Thermos Scientific 42i), and a Nanoparticle Surface Area Monitor (NSAM, TSI 3550) was used to measure the LDSA (reported as μm2 cm−3) corresponding to the alveolar region of the lung between November 2013 and November 2015. The average concentrations of particle number concentrations were observed in summer with lower absolute values of PNC than in winter might be related mainly to particles directly emitted by traffic and to the more favorable conditions of atmospheric dispersion. Results showed a traffic-related diurnal variation of UFP, BC, NOX and LDSA with clear morning and evening rush hour peaks on weekdays, only an evening peak at the weekends. Correlation coefficients were calculated between UFP and other pollutants (BC and NOX). The highest correlation between them was found in winter months. Overall, the results support the notion that local traffic emissions were a major contributor of the atmospheric particles pollution and a clear seasonal pattern was found, with higher values during the cold season.

Keywords: size distribution, traffic emissions, UFP, urban area

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4565 Various Advanced Statistical Analyses of Index Values Extracted from Outdoor Agricultural Workers Motion Data

Authors: Shinji Kawakura, Ryosuke Shibasaki

Abstract:

We have been grouping and developing various kinds of practical, promising sensing applied systems concerning agricultural advancement and technical tradition (guidance). These include advanced devices to secure real-time data related to worker motion, and we analyze by methods of various advanced statistics and human dynamics (e.g. primary component analysis, Ward system based cluster analysis, and mapping). What is more, we have been considering worker daily health and safety issues. Targeted fields are mainly common farms, meadows, and gardens. After then, we observed and discussed time-line style, changing data. And, we made some suggestions. The entire plan makes it possible to improve both the aforementioned applied systems and farms.

Keywords: advanced statistical analysis, wearable sensing system, tradition of skill, supporting for workers, detecting crisis

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4564 Numerical Solution of Space Fractional Order Solute Transport System

Authors: Shubham Jaiswal

Abstract:

In the present article, a drive is taken to compute the solution of spatial fractional order advection-dispersion equation having source/sink term with given initial and boundary conditions. The equation is converted to a system of ordinary differential equations using second-kind shifted Chebyshev polynomials, which have finally been solved using finite difference method. The striking feature of the article is the fast transportation of solute concentration as and when the system approaches fractional order from standard order for specified values of the parameters of the system.

Keywords: spatial fractional order advection-dispersion equation, second-kind shifted Chebyshev polynomial, collocation method, conservative system, non-conservative system

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4563 Gas-Solid Nitrocarburizing of Steels: Kinetic Modelling and Experimental Validation

Authors: L. Torchane

Abstract:

This study is devoted to defining the optimal conditions for the nitriding of pure iron at atmospheric pressure by using NH3-Ar-C3H8 gas mixtures. After studying the mechanisms of phase formation and mass transfer at the gas-solid interface, a mathematical model is developed in order to predict the nitrogen transfer rate in the solid, the ε-carbonitride layer growth rate and the nitrogen and carbon concentration profiles. In order to validate the model and to show its possibilities, it is compared with thermogravimetric experiments, analyses and metallurgical observations (X-ray diffraction, optical microscopy and electron microprobe analysis). Results obtained allow us to demonstrate the sound correlation between the experimental results and the theoretical predictions.

Keywords: gaseous nitrocarburizing, kinetic model, diffusion, layer growth kinetic

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4562 Optimal Performance of Plastic Extrusion Process Using Fuzzy Goal Programming

Authors: Abbas Al-Refaie

Abstract:

This study optimized the performance of plastic extrusion process of drip irrigation pipes using fuzzy goal programming. Two main responses were of main interest; roll thickness and hardness. Four main process factors were studied. The L18 array was then used for experimental design. The individual-moving range control charts were used to assess the stability of the process, while the process capability index was used to assess process performance. Confirmation experiments were conducted at the obtained combination of optimal factor setting by fuzzy goal programming. The results revealed that process capability was improved significantly from -1.129 to 0.8148 for roll thickness and from 0.0965 to 0.714 and hardness. Such improvement results in considerable savings in production and quality costs.

Keywords: fuzzy goal programming, extrusion process, process capability, irrigation plastic pipes

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4561 Liquefaction Phenomenon in the Kathmandu Valley during the 2015 Earthquake of Nepal

Authors: Kalpana Adhikari, Mandip Subedi, Keshab Sharma, Indra P. Acharya

Abstract:

The Gorkha Nepal earthquake of moment magnitude (Mw) 7.8 struck the central region of Nepal on April 25, 2015 with the epicenter about 77 km northwest of Kathmandu Valley . Peak ground acceleration observed during the earthquake was 0.18g. This motion induced several geotechnical effects such as landslides, foundation failures liquefaction, lateral spreading and settlement, and local amplification. An aftershock of moment magnitude (Mw) 7.3 hit northeast of Kathmandu on May 12 after 17 days of main shock caused additional damages. Kathmandu is the largest city in Nepal, have a population over four million. As the Kathmandu Valley deposits are composed mainly of sand, silt and clay layers with a shallow ground water table, liquefaction is highly anticipated. Extensive liquefaction was also observed in Kathmandu Valley during the 1934 Nepal-Bihar earthquake. Field investigations were carried out in Kathmandu Valley immediately after Mw 7.8, April 25 main shock and Mw 7.3, May 12 aftershock. Geotechnical investigation of both liquefied and non-liquefied sites were conducted after the earthquake. This paper presents observations of liquefaction and liquefaction induced damage, and the liquefaction potential assessment based on Standard Penetration Tests (SPT) for liquefied and non-liquefied sites. SPT based semi-empirical approach has been used for evaluating liquefaction potential of the soil and Liquefaction Potential Index (LPI) has been used to determine liquefaction probability. Recorded ground motions from the event are presented. Geological aspect of Kathmandu Valley and local site effect on the occurrence of liquefaction is described briefly. Observed liquefaction case studies are described briefly. Typically, these are sand boils formed by freshly ejected sand forced out of over-pressurized sub-strata. At most site, sand was ejected to agricultural fields forming deposits that varied from millimetres to a few centimeters thick. Liquefaction-induced damage to structures in these areas was not significant except buildings on some places tilted slightly. Boiled soils at liquefied sites were collected and the particle size distributions of ejected soils were analyzed. SPT blow counts and the soil profiles at ten liquefied and non-liquefied sites were obtained. The factors of safety against liquefaction with depth and liquefaction potential index of the ten sites were estimated and compared with observed liquefaction after 2015 Gorkha earthquake. The liquefaction potential indices obtained from the analysis were found to be consistent with the field observation. The field observations along with results from liquefaction assessment were compared with the existing liquefaction hazard map. It was found that the existing hazard maps are unrepresentative and underestimate the liquefaction susceptibility in Kathmandu Valley. The lessons learned from the liquefaction during this earthquake are also summarized in this paper. Some recommendations are also made to the seismic liquefaction mitigation in the Kathmandu Valley.

Keywords: factor of safety, geotechnical investigation, liquefaction, Nepal earthquake

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4560 Long Memory and ARFIMA Modelling: The Case of CPI Inflation for Ghana and South Africa

Authors: A. Boateng, La Gil-Alana, M. Lesaoana; Hj. Siweya, A. Belete

Abstract:

This study examines long memory or long-range dependence in the CPI inflation rates of Ghana and South Africa using Whittle methods and autoregressive fractionally integrated moving average (ARFIMA) models. Standard I(0)/I(1) methods such as Augmented Dickey-Fuller (ADF), Philips-Perron (PP) and Kwiatkowski–Phillips–Schmidt–Shin (KPSS) tests were also employed. Our findings indicate that long memory exists in the CPI inflation rates of both countries. After processing fractional differencing and determining the short memory components, the models were specified as ARFIMA (4,0.35,2) and ARFIMA (3,0.49,3) respectively for Ghana and South Africa. Consequently, the CPI inflation rates of both countries are fractionally integrated and mean reverting. The implication of this result will assist in policy formulation and identification of inflationary pressures in an economy.

Keywords: Consumer Price Index (CPI) inflation rates, Whittle method, long memory, ARFIMA model

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4559 Determination of the Phytochemicals Composition and Pharmacokinetics of whole Coffee Fruit Caffeine Extract by Liquid Chromatography-Tandem Mass Spectrometry

Authors: Boris Nemzer, Nebiyu Abshiru, Z. B. Pietrzkowski

Abstract:

Coffee cherry is one of the most ubiquitous agricultural commodities which possess nutritional and human health beneficial properties. Between the two most widely used coffee cherries Coffea arabica (Arabica) and Coffea canephora (Robusta), Coffea arabica remains superior due to its sensory properties and, therefore, remains in great demand in the global coffee market. In this study, the phytochemical contents and pharmacokinetics of Coffeeberry® Energy (CBE), a commercially available Arabica whole coffee fruit caffeine extract, are investigated. For phytochemical screening, 20 mg of CBE was dissolved in an aqueous methanol solution for analysis by mass spectrometry (MS). Quantification of caffeine and chlorogenic acids (CGAs) contents of CBE was performed using HPLC. For the bioavailability study, serum samples were collected from human subjects before and after 1, 2 and 3 h post-ingestion of 150mg CBE extract. Protein precipitation and extraction were carried out using methanol. Identification of compounds was performed using an untargeted metabolomic approach on Q-Exactive Orbitrap MS coupled to reversed-phase chromatography. Data processing was performed using Thermo Scientific Compound Discover 3.3 software. Phytochemical screening identified a total of 170 compounds, including organic acids, phenolic acids, CGAs, diterpenoids and hydroxytryptamine. Caffeine & CGAs make up more than, respectively, 70% & 9% of the total CBE composition. For serum samples, a total of 82 metabolites representing 32 caffeine- and 50 phenolic-derived metabolites were identified. Volcano plot analysis revealed 32 differential metabolites (24 caffeine- and 8 phenolic-derived) that showed an increase in serum level post-CBE dosing. Caffeine, uric acid, and trimethyluric acid isomers exhibited 4- to 10-fold increase in serum abundance post-dosing. 7-Methyluric acid, 1,7-dimethyluric acid, paraxanthine and theophylline exhibited a minimum of 1.5-fold increase in serum level. Among the phenolic-derived metabolites, iso-feruloyl quinic acid isomers (3-, 4- and 5-iFQA) showed the highest increase in serum level. These compounds were essentially absent in serum collected before dosage. More interestingly, the iFQA isomers were not originally present in the CBE extract, as our phytochemical screen did not identify these compounds. This suggests the potential formation of the isomers during the digestion and absorption processes. Pharmacokinetics parameters (Cmax, Tmax and AUC0-3h) of caffeine- and phenolic-derived metabolites were also investigated. Caffeine was rapidly absorbed, reaching a maximum concentration (Cmax) of 10.95 µg/ml in just 1 hour. Thereafter, caffeine level steadily dropped from the peak level, although it did not return to baseline within the 3-hour dosing period. The disappearance of caffeine from circulation was mirrored by the rise in the concentration of its methylxanthine metabolites. Similarly, serum concentration of iFQA isomers steadily increased, reaching maximum (Cmax: 3-iFQA, 1.54 ng/ml; 4-iFQA, 2.47 ng/ml; 5-iFQA, 2.91 ng/ml) at tmax of 1.5 hours. The isomers remained well above the baseline during the 3-hour dosing period, allowing them to remain in circulation long enough for absorption into the body. Overall, the current study provides evidence of the potential health benefits of a uniquely formulated whole coffee fruit product. Consumption of this product resulted in a distinct serum profile of bioactive compounds, as demonstrated by the more than 32 metabolites that exhibited a significant change in systemic exposure.

Keywords: phytochemicals, mass spectrometry, pharmacokinetics, differential metabolites, chlorogenic acids

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4558 Environmental Implications of Groundwater Quality in Irrigated Agriculture in Kebbi State, Nigeria

Authors: O. I. Ojo, W. B. R. Graham, I. W. Pishiria

Abstract:

The quality of groundwater used for irrigation in Kebbi State, northwestern Nigeria was evaluated. Open-well, tube-well and borehole water samples were collected from various locations in the State. The water samples analyzed had pH values below the normal range for irrigation water and very low to moderate salinity (electrical conductivity 0.05-0.82 dS.m-1). The adjusted sodium adsorption ratio values in all the samples were also very low (<0.2), indicating very low sodicity hazards. However, irrigation water of very low salinity (<0.2dS.m-1) and low SAR can lead to problems of infiltration into soils. The Ca: Mg ratio (<1) in most of the samples may lead to Ca deficiency in soils after long term use. The nitrate concentration in most of the samples was high ranging from 4.5 to >50mg/L.

Keywords: ground water quality, irrigation, characteristics, soil drainage, salinity, Fadama

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4557 Dynamic Characterization of Shallow Aquifer Groundwater: A Lab-Scale Approach

Authors: Anthony Credoz, Nathalie Nief, Remy Hedacq, Salvador Jordana, Laurent Cazes

Abstract:

Groundwater monitoring is classically performed in a network of piezometers in industrial sites. Groundwater flow parameters, such as direction, sense and velocity, are deduced from indirect measurements between two or more piezometers. Groundwater sampling is generally done on the whole column of water inside each borehole to provide concentration values for each piezometer location. These flow and concentration values give a global ‘static’ image of potential plume of contaminants evolution in the shallow aquifer with huge uncertainties in time and space scales and mass discharge dynamic. TOTAL R&D Subsurface Environmental team is challenging this classical approach with an innovative dynamic way of characterization of shallow aquifer groundwater. The current study aims at optimizing the tools and methodologies for (i) a direct and multilevel measurement of groundwater velocities in each piezometer and, (ii) a calculation of potential flux of dissolved contaminant in the shallow aquifer. Lab-scale experiments have been designed to test commercial and R&D tools in a controlled sandbox. Multiphysics modeling were performed and took into account Darcy equation in porous media and Navier-Stockes equation in the borehole. The first step of the current study focused on groundwater flow at porous media/piezometer interface. Huge uncertainties from direct flow rate measurements in the borehole versus Darcy flow rate in the porous media were characterized during experiments and modeling. The structure and location of the tools in the borehole also impacted the results and uncertainties of velocity measurement. In parallel, direct-push tool was tested and presented more accurate results. The second step of the study focused on mass flux of dissolved contaminant in groundwater. Several active and passive commercial and R&D tools have been tested in sandbox and reactive transport modeling has been performed to validate the experiments at the lab-scale. Some tools will be selected and deployed in field assays to better assess the mass discharge of dissolved contaminants in an industrial site. The long-term subsurface environmental strategy is targeting an in-situ, real-time, remote and cost-effective monitoring of groundwater.

Keywords: dynamic characterization, groundwater flow, lab-scale, mass flux

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4556 Investigating the Effect of Plant Root Exudates and of Saponin on Polycyclic Aromatic Hydrocarbons Solubilization in Brownfield Contaminated Soils

Authors: Marie Davin, Marie-Laure Fauconnier, Gilles Colinet

Abstract:

In Wallonia, there are 6,000 estimated brownfields (rising to over 3.5 million in Europe) that require remediation. Polycyclic Aromatic Hydrocarbons (PAHs) are a class of recalcitrant carcinogenic/mutagenic organic compounds of major concern as they accumulate in the environment and represent 17% of all encountered pollutants. As an alternative to environmentally aggressive, expensive and often disruptive soil remediation strategies, a lot of research has been directed to developing techniques targeting organic pollutants. The following experiment, based on the observation that PAHs soil content decreases in the presence of plants, aimed at improving our understanding of the underlying mechanisms involved in phytoremediation. It focusses on plant root exudates and whether they improve PAHs solubilization, which would make them more available for bioremediation by soil microorganisms. The effect of saponin, a natural surfactant found in some plant roots such as members of the Fabaceae family, on PAHs solubilization was also investigated as part of the implementation of the experimental protocol. The experiments were conducted on soil collected from a brownfield in Saint-Ghislain (Belgium) and presenting weathered PAHs contamination. Samples of soil were extracted with different solutions containing either plant root exudates or commercial saponin. Extracted PAHs were determined in the different aqueous solutions using High-Performance Liquid Chromatography and Fluorimetric Detection (HPLC-FLD). Both root exudates of alfalfa (Medicago sativa L.) or red clover (Trifolium pratense L.) and commercial saponin were tested in different concentrations. Distilled water was used as a control. First of all, results show that PAHs are more extracted using saponin solutions than distilled water and that the amounts generally rise with the saponin concentration. However, the amount of each extracted compound diminishes as its molecular weight rises. Also, it appears that passed a certain surfactant concentration, PAHs are less extracted. This suggests that saponin might be investigated as a washing agent in polluted soil remediation techniques, either for ex-situ or in-situ treatments, as an alternative to synthetic surfactants. On the other hand, preliminary results on experiments using plant root exudates also show differences in PAHs solubilization compared to the control solution. Further results will allow discussion as to whether or not there are differences according to the exudates provenance and concentrations.

Keywords: brownfield, Medicago sativa, phytoremediation, polycyclic aromatic hydrocarbons, root exudates, saponin, solubilization, Trifolium pratense

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4555 Diselenide-Linked Redox Stimuli-Responsive Methoxy Poly(Ethylene Glycol)-b-Poly(Lactide-Co-Glycolide) Micelles for the Delivery of Doxorubicin in Cancer Cells

Authors: Yihenew Simegniew Birhan, Hsieh Chih Tsai

Abstract:

The recent advancements in synthetic chemistry and nanotechnology fostered the development of different nanocarriers for enhanced intracellular delivery of pharmaceutical agents to tumor cells. Polymeric micelles (PMs), characterized by small size, appreciable drug loading capacity (DLC), better accumulation in tumor tissue via enhanced permeability and retention (EPR) effect, and the ability to avoid detection and subsequent clearance by the mononuclear phagocyte (MNP) system, are convenient to improve the poor solubility, slow absorption and non-selective biodistribution of payloads embedded in their hydrophobic cores and hence, enhance the therapeutic efficacy of chemotherapeutic agents. Recently, redox-responsive polymeric micelles have gained significant attention for the delivery and controlled release of anticancer drugs in tumor cells. In this study, we synthesized redox-responsive diselenide bond containing amphiphilic polymer, Bi(mPEG-PLGA)-Se₂ from mPEG-PLGA, and 3,3'-diselanediyldipropanoic acid (DSeDPA) using DCC/DMAP as coupling agents. The successful synthesis of the copolymers was verified by different spectroscopic techniques. Above the critical micelle concentration, the amphiphilic copolymer, Bi(mPEG-PLGA)-Se₂, self-assembled into stable micelles. The DLS data indicated that the hydrodynamic diameter of the micelles (123.9 ± 0.85 nm) was suitable for extravasation into the tumor cells through the EPR effect. The drug loading content (DLC) and encapsulation efficiency (EE) of DOX-loaded micelles were found to be 6.61 wt% and 54.9%, respectively. The DOX-loaded micelles showed initial burst release accompanied by sustained release trend where 73.94% and 69.54% of encapsulated DOX was released upon treatment with 6mM GSH and 0.1% H₂O₂, respectively. The biocompatible nature of Bi(mPEG-PLGA)-Se₂ copolymer was confirmed by the cell viability study. In addition, the DOX-loaded micelles exhibited significant inhibition against HeLa cells (44.46%), at a maximum dose of 7.5 µg/mL. The fluorescent microscope images of HeLa cells treated with 3 µg/mL (equivalent DOX concentration) revealed efficient internalization and accumulation of DOX-loaded Bi(mPEG-PLGA)-Se₂ micelles in the cytosol of cancer cells. In conclusion, the intelligent, biocompatible, and the redox stimuli-responsive behavior of Bi(mPEG-PLGA)-Se₂ copolymer marked the potential applications of diselenide-linked mPEG-PLGA micelles for the delivery and on-demand release of chemotherapeutic agents in cancer cells.

Keywords: anticancer drug delivery, diselenide bond, polymeric micelles, redox-responsive

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4554 Removal of Perchloroethylene, a Common Pollutant, in Groundwater Using Activated Carbon

Authors: Marianne Miguet, Gaël Plantard, Yves Jaeger, Vincent Goetz

Abstract:

The contamination of groundwater is a major concern. A common pollutant, the perchloroethylene, is the target contaminant. Water treatment process as Granular Activated Carbons are very efficient but requires pilot-scale testing to determine the full-scale GAC performance. First, the batch mode was used to get a reliable experimental method to estimate the adsorption capacity of a common volatile compound is settled. The Langmuir model is acceptable to fit the isotherms. Dynamic tests were performed with three columns and different operating conditions. A database of concentration profiles and breakthroughs were obtained. The resolution of the set of differential equations is acceptable to fit the dynamics tests and could be used for a full-scale adsorber.

Keywords: activated carbon, groundwater, perchloroethylene, full-scale

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4553 Application of Model Tree in the Prediction of TBM Rate of Penetration with Synthetic Minority Oversampling Technique

Authors: Ehsan Mehryaar

Abstract:

The rate of penetration is (RoP) one of the vital factors in the cost and time of tunnel boring projects; therefore, predicting it can lead to a substantial increase in the efficiency of the project. RoP is heavily dependent geological properties of the project site and TBM properties. In this study, 151-point data from Queen’s water tunnel is collected, which includes unconfined compression strength, peak slope index, angle with weak planes, and distance between planes of weaknesses. Since the size of the data is small, it was observed that it is imbalanced. To solve that problem synthetic minority oversampling technique is utilized. The model based on the model tree is proposed, where each leaf consists of a support vector machine model. Proposed model performance is then compared to existing empirical equations in the literature.

Keywords: Model tree, SMOTE, rate of penetration, TBM(tunnel boring machine), SVM

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4552 Optimization of Artisanal Fishing Waste Fermentation for Volatile Fatty Acids Production

Authors: Luz Stella Cadavid-Rodriguez, Viviana E. Castro-Lopez

Abstract:

Fish waste (FW) has a high content of potentially biodegradable components, so it is amenable to be digested anaerobically. In this line, anaerobic digestion (AD) of FW has been studied for biogas production. Nevertheless, intermediate products such as volatile fatty acids (VFA), generated during the acidogenic stage, have been scarce investigated, even though they have a high potential as a renewable source of carbon. In the literature, there are few studies about the Inoculum-Substrate (I/S) ratio on acidogenesis. On the other hand, it is well known that pH is a critical factor in the production of VFA. The optimum pH for the production of VFA seems to change depending on the substrate and can vary in a range between 5.25 and 11. Nonetheless, the literature about VFA production from protein-rich waste, such as FW, is scarce. In this context, it is necessary to deepen on the determination of the optimal operating conditions of acidogenic fermentation for VFA production from protein-rich waste. Therefore, the aim of this research was to optimize the volatile fatty acid production from artisanal fishing waste, studying the effect of pH and the I/S ratio on the acidogenic process. For this research, the inoculum used was a methanogenic sludge (MS) obtained from a UASB reactor treating wastewater of a slaughterhouse plant, and the FW was collected in the port of Tumaco (Colombia) from the local artisanal fishers. The acidogenic fermentation experiments were conducted in batch mode, in 500 mL glass bottles as anaerobic reactors, equipped with rubber stoppers provided with a valve to release biogas. The effective volume used was 300 mL. The experiments were carried out for 15 days at a mesophilic temperature of 37± 2 °C and constant agitation of 200 rpm. The effect of 3 pH levels: 5, 7, 9, coupled with five I/S ratios, corresponding to 0.20, 0.15, 0.10, 0.05, 0.00 was evaluated taking as a response variable the production of VFA. A complete randomized block design was selected for the experiments in a 5x3 factorial arrangement, with two repetitions per treatment. At the beginning and during the process, pH in the experimental reactors was adjusted to the corresponding values of 5, 7, and 9 using 1M NaOH or 1M H2SO4, as was appropriated. In addition, once the optimum I/S ratio was determined, the process was evaluated at this condition without pH control. The results indicated that pH is the main factor in the production of VFA, obtaining the highest concentration with neutral pH. By reducing the I/S ratio, as low as 0.05, it was possible to maximize VFA production. Thus, the optimum conditions found were natural pH (6.6-7.7) and I/S ratio of 0.05, with which it was possible to reach a maximum total VFA concentration of 70.3 g Ac/L, whose major components were acetic acid (35%) and butyric acid (32%). The findings showed that the acidogenic fermentation of FW is an efficient way of producing VFA and that the operating conditions can be simple and economical.

Keywords: acidogenesis, artisanal fishing waste, inoculum to substrate ratio, volatile fatty acids

Procedia PDF Downloads 107
4551 Ionic Liquids as Corrosion Inhibitors in CO2 Capture Systems

Authors: A. Acidi, A. Abbaci

Abstract:

We present the viability of using thermally stable, practically non-volatile ionic liquids as corrosion inhibitors in aqueous monoethanolamine system. Carbon steel 1020, which widely used as construction material in CO2 capture plants, has been taken as a test material. Corrosion inhibition capacities of typical room-temperature ionic liquids constituting imidazolium cation in concentration range ≤ 3% by weight in CO2 capture applications were investigated. Electrochemical corrosion experiments using the potentiodynamic polarization technique for measuring corrosion current were carried out. The results show that ionic liquids possess ability to suppressing severe operational problems of corrosion in typical CO2 capture plants.

Keywords: carbon dioxide, carbon steel, monoethanolamine, corrosion rate, ionic liquids, tafel fit

Procedia PDF Downloads 309
4550 Numerical Investigation of Plasma-Fuel System (PFS) for Coal Ignition and Combustion

Authors: Vladimir Messerle, Alexandr Ustimenko, Oleg Lavrichshev

Abstract:

To enhance the efficiency of solid fuels’ use, to decrease the fuel oil rate in the thermal power plants fuel balance and to minimize harmful emissions, a plasma technology of coal ignition, gasification and incineration is successfully applied. This technology is plasma thermochemical preparation of fuel for burning (PTCPF). In the framework of this concept, some portion of pulverized solid fuel (PF) is separated from the main PF flow and undergone the activation by arc plasma in a specific chamber with plasma torch – PFS. The air plasma flame is a source of heat and additional oxidation, it provides a high-temperature medium enriched with radicals, where the fuel mixture is heated, volatile components of coal are extracted, and carbon is partially gasified. This active blended fuel can ignite the main PF flow supplied into the furnace. This technology provides the boiler start-up and stabilization of PF flame and eliminates the necessity for addition of highly reactive fuel. In the report, a model of PTCPF, implemented as a program PlasmaKinTherm for the PFS calculation is described. The model combines thermodynamic and kinetic methods for describing the process of PTCPF in PFS. The numerical investigation of operational parameters of PFS depending on the electric power of the plasma generator and steam coal ash content revealed the temperature and velocity of gas and coal particles, and concentrations of PTCPF products dependences on the PFS length. Main mechanisms of PTCPF were disclosed. It was found that in the range of electric power of plasma generator from 40 to 100 kW high ash bituminous coal, having consumption 1667 kg/h is ignited stably. High level of temperature (1740 K) and concentration of combustible components (44%) at the PFS exit is a confirmation of it. Augmentation in power of plasma generator results displacement maxima temperatures and speeds of PTCPF products upstream (in the direction of the plasma source). The maximum temperature and velocity vary in a narrow range of values and practically do not depend on the power of the plasma torch. The numerical study of indicators of the process of PTCPF depending on the ash content in the range of its values 20-70% demonstrated that at the exit of PFS concentration of combustible components decreases with an increase in coal ash, the temperature of the gaseous products is increasing, and coal carbon conversion rate is increased to a maximum value when the ash content of 60%, dramatically decreasing with further increase in the ash content.

Keywords: coal, efficiency, ignition, numerical modeling, plasma generator, plasma-fuel system

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4549 TiO₂ Nanoparticles Induce DNA Damage and Expression of Biomarker of Oxidative Stress on Human Spermatozoa

Authors: Elena Maria Scalisi

Abstract:

The increasing production and the use of TiO₂ nanoparticles (NPs) have inevitably led to their release into the environment, thereby posing a threat to organisms and also for human. Human exposure to TiO₂-NPs may occur during both manufacturing and use. TiO₂-NPs are common in consumer products for dermal application, toothpaste, food colorants, and nutritional supplements, then oral exposure may occur during use of such products. Into the body, TiO₂-NPs thanks to their small size (<100 nm), can, through testicular blood barrier inducing effect on testis and then on male reproductive health. The nanoscale size of TiO₂ increase the surface-to-volume ratio making them more reactive in a cell, then TiO₂ NPs increase their ability to produce reactive oxygen species (ROS). In male germ cells, ROS may have important implications in maintaining the normal functions of mature spermatozoa at physiological levels, moreover, in spermatozoa they are important signaling molecules for their hyperactivation and acrosome reaction. Nevertheless, an excess of ROS by external inputs such as NPs can increased the oxidative stress (OS), which results in damage DNA and apoptosis. The aim of our study has been investigate the impact of TiO₂ NPs on human spermatozoa, evaluating DNA damage and the expression of proteins involved in cell stress. According WHO guidelines 2021, we have exposed human spermatozoa in vitro to TiO₂ NP at concentrations 50 ppm, 100 ppm, 250 ppm, and 500 ppm for 1 hour (at 37°C and CO₂ at 5%). DNA damage was evaluated by Sperm Chromatin Dispersion Test (SCD) and TUNEL assay; moreover, we have evaluated the expression of biomarkers of oxidative stress like Heat Shock Protein 70 (HSP70) and Metallothioneins (MTs). Also, sperm parameters as motility viability have been evaluated. Our results not report a significant reduction in motility of spermatozoa at the end of the exposure. On the contrary, the progressive motility was increased at the highest concentration (500 ppm) and was statistically significant compared to control (p <0.05). Also, viability was not changed by exposure to TiO₂-NPs (p <0.05). However, increased DNA damage was observed at all concentrations, and the TUNEL assay highlighted the presence of single strand breaks in the DNA. The spermatozoa responded to the presence of TiO₂-NPs with the expression of Hsp70, which have a protective function because they allow the maintenance of cellular homeostasis in stressful/ lethal conditions. A positivity for MTs was observed mainly for the concentration of 4 mg/L. Although the biological and physiological function of the metallothionein (MTs) in the male genital organs is unclear, our results highlighted that the MTs expressed by spermatozoa maintain their biological role of detoxification from metals. Our results can give additional information to the data in the literature on the toxicity of TiO₂-NPs and reproduction.

Keywords: human spermatozoa, DNA damage, TiO₂-NPs, biomarkers

Procedia PDF Downloads 136