Master Tezleri

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Ambient air persistent organic pollutant monitoring, backtrajectory modeling, and health risk assessment
(Izmir Institute of Technology, 2015-07) Güngörmüş, Elif; Sofuoğlu, Aysun; Sofuoğlu, Sait Cemil
Turkish Government has officially become a party to the Stockholm Convention as of 2010, therefore, determination of POPs in environmental compartments in Turkey is a critical concern. In this study, 22 organochlorine pesticides (OCPs) and 43 polychlorinated biphenyls (PCBs) were measured in gas and particulate phases of ambient air samples collected in Izmir and Istanbul from May to October 2014 on a weekly basis. Gas chromatography–mass spectrometry was used to quantify the targeted pollutants. Potential source regions were assessed by applying back-trajectory and Potential Source Contribution Function (PSCF). Population carcinogenic risk levels associated with inhalation exposure were estimated by using Monte Carlo simulation, for which sensitivity and uncertainty analyses were also conducted. The highest mean concentration compounds were heptachlor (61±126 pg/m3) and p,p’-DDE (54±57 pg/m3) in Izmir and Istanbul, respectively. The mean Ʃ43PCBs concentration was found as 232±224 pg/m3 in Izmir, and 104±48 pg/m3 in Istanbul. Gas phase concentartions of OCPs and PCBs were generally much higher than particle phase. The PSCF results pointed out different potential source regions: Middle East, Eurasia, and Europe. All the estimated carcinogenic risks based on the 95% percentile values for individual OCPs and Ʃ43PCBs were calculated below the acceptable risk levels (10-6), indicating no significant potential health risk via inhalation route.
Anaerobic co-treatability of olive mill wastewaters and domestic wastewater
(Izmir Institute of Technology, 2003-09) Atayol, Ahmet Avni; Sofuoğlu, Aysun
Handling of olive mill wastewater (OMW) constitute an important problem for Mediterranean countries in general and western parts of Turkey in particular. This wastewater is seasonally produced and has high organic pollutant concentrations. Many treatment methods have been tried for its treatment, but a method having both sufficient treatment efficiency and economical feasibility could not be offered.Anaerobic treatment, having the advantages of applicability to high-strength and/or seasonal wastewaters, energy production and reduced costs, may be a good option. But olive mill wastewater is considered still to be highly polluted and not to have sufficient nutrients while domestic wastewater (DW) is assessed to be dilute and to have nutrients in excess for anaerobic treatment. Therefore anaerobic co-treatment of these wastewaters may be a better solution.In this study, the anaerobic co-treatability of OMW and DW was investigated by means of anaerobic treatability assays called Biochemical Methane Potential (BMP) tests. These tests were applied to OMW and DW mixtures of different ratios (OMW:DW of 1:9, 1:5, 1:3, 1:1, 1:0) at different organic loadings (4553 mg/l, 9107 mg/l, 13660 mg/l, 22767 mg/l and 34150 mg/l Chemical Oxygen Demand (COD) loading) with two different seed cultures. In order to determine the effect of nutrient addition, and the complementarity of these wastewaters, all tests were carried out both with (BM+) and without (BM-) the addition of a nutrient solution (basal medium).Results of the experiments showed treatment efficiencies around 80% at 4553 mg/l COD loading and around 70% at higher loadings for samples seeded with the culture obtained from the treatment plant of Efes Pilsen Brewery in İzmir, Turkey. For samples seeded with the culture obtained from the anaerobic digesters of Ankara Municipal Wastewater Treatment Plant, results were between 61% and 82% with the higher efficiencies at medium COD loading levels. A meaningful relation between DW content and treatment efficiency could not be observed; but the performance ratio of BMreactors to BM+ reactors increased with increasing DW content in the mixture, indicating the positive effect of DW addition. Reactors seeded with Efes culture did not require an acclimation period, while those seeded with Ankara culture did so. Efes seeded reactors, at all COD loadings, performed most of the gas production, around 75-80%, in about 15-20 days. Ankara seeded BM+ reactors required about 25 days for 80% production, while this period was about 35-45 days for BM- reactors.
Assessmanet of exposure and risk associated with trihalomethanes and other volatile organic compounds in drinking water
(Izmir Institute of Technology, 2005) Kavcar, Pınar; Sofuoğlu, Sait Cemil
Concentrations of 54 volatile organic compounds (VOCs) were measured in İzmir drinking water, and associated health risks due to ingestion of these compounds were investigated using a semi-probabilistic sampling design. 100 houses were visited in different districts of İzmir and drinking water samples were collected from consumer taps and bottled waters. Using questionnaires, demographics and drinking water consumption rates were determined. Individual and population based exposures and risks were estimated by employing deterministic and probabilistic approaches, respectively.Trihalomethanes (THMs) (i.e., chloroform, bromodichloromethane, dibromochloromethane, and bromoform), benzene, toluene, p-xylene, and naphthalene were the most frequently detected VOCs in İzmir drinking water with concentrations ranging from below detection limit to 35 .g/l. None of the samples exceeded the maximum contaminant levels stated in the Turkish, European, and American drinking water regulations. For all VOCs, the concentrations measured in metropolitan area were greater than those in other districts. All THM species were detected in higher concentrations in tap water.Noncarcinogenic risks attributable to ingestion of VOCs in İzmir drinking water were negligible whereas the mean carcinogenic risk estimates for bromodichloromethane and dibromochloromethane were above the acceptable level of one in a million (10-6). Deterministic approach revealed that 23%, 29%, and 2% of individuals had lifetime cancer risks greater than 10-6 associated with ingestion of bromodichloromethane, dibromochloromethane, and bromoform, respectively. The results of this study show that exposures to drinking water contaminants and associated risks may be higher than the acceptable level even if the concentrations fall below the drinking water standards.
Biosortion of nickel (II) by using waste baker's yeast
(Izmir Institute of Technology, 2001) Özdemir, Peruze; Harsa, Hayriye Şebnem
3 Biological methods for removing heavy metals are in competition with chemical and physical techniques such as precipitation, ion exchange, electrochemical treatment and evaporative recovery, especially, when the concentration of the heavy metal ion is low, between 1.0 and 100 mg/L. In order to qualify for industrial applications, biosorbents have to be produced at low cost. The use of biomass from various production stages; e.g. from the pharmaceutical or the food industries, is one way to minimize the costs. This study is concerned with the binding of nickel ions onto waste biomass of Saccharomyces cerevisiae genus, obtained from the food industry. Since the biomass employed is a waste material, biosorption process described in this study may represent a cheap alternative to conventional methods.Biomass cell walls, consisting mainly of polysaccharides, proteins and lipids, offer many functional groups which can bind metal ions such as carboxylate, hydroxyl, phosphate and amino groups.The objective of this study was to investigate the adsorption of nickel on wastebaker.s yeast as a function of several factors, i.e. pretreatment, pH, temperature, biomass concentrations and initial metal concentrations, in order to determine the optimum adsorption conditions of a batch process.Pretreatment of waste yeast biomass using sodium hydroxide, formaldehyde, nitric acid and ethanol decreased the sorption of nickel (II) ions compared with live biomass. Optimum initial pH for nickel (II) ions was 5.0 at the optimum temperature of 25o C. The uptake values increased with the increasing initial nickel (II) ion concentrations up to 150 mg/L. The optimum biomass concentration for this process was determined as 1.0 g/L.The biosorption isotherms were developed at various initial pH and temperature values. The equilibrium values were expressed with the Langmuir model while nickel sorption did not fit the Freundlich plot. The Langmuir parameters qmax (14.30 mg/L) and b (0.0069 L/mg) have been calculated."qmax" increased from 7.8 to 14.30 mg/L with the increase in pH from 3.0 to 5.0. Similar trend was observed for the "b" values; an increase from 0.0025 to 0.0069 L/mg were obtained when the pH of the solution was raised from 3.0 to 5.0. Both Langmuir model parameters were found to be the highest values at pH 5.0 which is consistent with the results of the optimization studies as described above.Temperature also affected the phase equilibria of nickel (II)/S.cerevisiae system.The highest capacity for biosorption system was obtained at 25o C with the qmax and b values of 14.3 mg/L and 0.0069 L/mg at pH 5.0, respectively. The enthalpy change for the biosorption process have been evaluated by using the Langmuir constant "b", which is related to the energy of adsorption. Nickel (II) biosorption is considered to be an exothermic process since low binding occurs when the temperature increases from 25 to 45o C.The uptake of nickel (II) ions by the yeast biomass was also investigated with respect to time under optimum operating conditions. Biosorption kinetics were rapid within the first few minutes. After the initial rapid uptake, further biosorption by yeast cells continued slowly and reached an equilibrium after 2 hours at all pH values of 3.0, 4.0 and 5.0. On the other hand, the rate of adsorption was found to be the fastest at pH 5.0 with an initial rate of around 3.59 mg Ni (II) / g-min.
Co-production of chitin nanofibers, proteins, and lipids in marine diatoms belonging to the Thalassiosira genus
(Izmir Institute of Technology, 2022-06) Sezgin, Tuğçe; Özkan, Altan
Chitin is a biopolymer used in various industries, including biomedical, pharmaceutical, medical, and food. Today, the vast majority of chitin is obtained from waste shellfish. Shellfish chitin has an inherent impurity problem because chitin in these organisms is embedded in other organics and inorganics. Thus, new sources have been investigated. Diatoms, particularly Thalassiosira and Cyclotella species, have the potential to be the providers for applications requiring high quality through their unique ability to biosynthesize and extrude chitin nanofibers. The primary aim of this study is to study this potential. This investigation entailed the cultivation of three Thalassiosira strains according to a standard cultivation protocol under photobioreactor conditions. The secondary aim was to assess the possibility of commercially valuable co-product generation. For this, biomass protein, lipid, and fatty acids contents were analyzed. Chitin productivity varied significantly between the strains. The peak productivities and final concentrations ranged from 4 to 25 mg/L-day and from 60 to 250 mg/L, respectively. Average fiber diameters ranged from 68.5 to 95.0 nm. Silicon limited growth increased the chitin biosynthesis in T.weissflogii 1336 and T.pseudonana 2135. Biomass lipid contents of over 45% were obtained with T.pseudonana 2135 under silicon depletion. The fatty acid profiles indicated the suitability for application as live aquaculture feed for T.weissflogii 1336, and biodiesel feedstock material for T.pseudonana 2135. The highest biomass protein contents were about 30%, which were obtained under silicon availability. This study, for the first time, assessed the chitin productivity of Thalassiosira strains and demonstrated unique multiproduct generation scenarios.
Design and tests of a geothermal dryer and determination of quality parameters of dried product
(Izmir Institute of Technology, 2012-12) Helvacı, Hüseyin Utku; Gökçen Akkurt, Gülden
Drying which is a heat and mass transfer process between the product surface and its surrounding medium and within the product is practised to enhance the storage life and reduce transportation costs of products. Olive leaves are the plants which have been used for medicinal purposes are often dried before use. Renewable energy sources such as geothermal energy can be used in drying processes as heat source besides fossil fuels. The temperature and the thermal potential of geothermal resources in Turkey is high enough to be used in drying process. In this thesis, a geothermal cabinet type drier was constructed and placed in Balcova-Narlidere geothermal field. To be able to determine drying parameters (temperature and velocity) and whose effects on drying kinetics of olive leaves and on the quality parameters of dried olive leaves (antioxidant content and phenolic content), drying experiments were carried out at three different air temperatures (40, 50 and 60 Â°C) and at three air velocities (0.5, 1, 1.5 m/s). During the experiments temperature, relative humidity and velocity of drying air was measured and recorded. Then, using the measured data drying time, drying rate, moisture ratio and effective diffusivity was determined and moisture ratio was modelled using thin-layer models. The quality parameters which are total antioxidant activity and total phenolic content were determined using spectrophotometric techniques. To evaluate the performance of the dryer, energy and exergy analyses were conducted. The drying time was determined as 240 â€“ 555 min. (4 â€“ 10) hour which is quite short comparing with open air sun drying. Optimum drying air temperature and velocity which gives the minimum total phenolic content and antioxidant loss value were determined by response surface methodology as 50 Â°C and 1 m/s, respectively. The energy utilization was found 0.3316 kW and the energy utilization ratios were found 50.36% and 7.96% for the case at drying air is re-circulated and the case at drying air was no re-circulated, respectively.
Determination of gas-particle partitioning parameters and indoor air concentrations of synthetic musk compounds
(Izmir Institute of Technology, 2013) Özcan, Çiğdem; Sofuoğlu, Aysun
Gas-particle partitioning of compounds is the key process determining the fate of chemical in the environment. The partitioning process can be modeled depending upon dominancy of being adsorptive or absorptive partitioning and referred with partition coefficient (Kp m3.Î¼g-1). Kp is related to liquid phase vapor pressure of a compound of interest. Due to difficulty related to model parameters, researchers have been developed a parameter called octanol air partition coefficient, KOA which can be directly measured and used to estimate Kp. Synthetic musk compounds (SMCs) are the one group of semi volatile organic compounds which are resistant to degradation, lipophilic and have moderate vapor pressures. They have been widely used in detergents, soaps, cosmetics, perfumes to give nice odorous effect for the product of interest. Most of their chemical properties values based on estimation methods. This study designed to measure octanol-air partition coefficients (KOA) and supercooled liquid vapor pressures (PL) by GC retention time method as a function of temperature to estimate gas-particle partitioning of SMCs. In addition ten indoor air gas and particulate phase samples were collected from a university cafeteria to determine experimental partition coefficient in the indoor air environment. The log KOA and log PL values of synthetic musk compounds were ranged between 6.42 to 8.77 and 0.52 to -4.53, respectively at 25 0C. All of the compounds were detected in the gas phase and the concentrations ranged from 0.27 ng/m3 to 106.8 ng/m3. In the particulate phase only DPMI, ADBI, ATII, MX and MK were detected in the range of 0.06 ng/m3 to 210.5 ng/m3. Although the correlation between the gas-particle partitioning coefficient (KP) and PL was found as weak, KOA was determined as a good descriptor for gas-particle partitioning process.
Effect of high saline geothermal fluid on soil and surface water: A case study from Tuzla, Çanakkale-Turkey
(Izmir Institute of Technology, 2013) Katırcıoğlu, Gamze; Baba, Alper
Geothermal energy can be defined as a heat from core of Earth and utilized for power generation, district heating and greenhouse. Use of geothermal energy has low environmental impact, particularly when compared with fossil fuels. However, geothermal fluid has some adverse effects for environment for instance contamination of surface water and soil. Examples of these effects occur in different parts of world. The objective of this study is to evaluate the effect of geothermal fluid particularly on surface water and soil in Tuzla Geothermal Field (TGF) where is located on Biga Peninsula, in the northwestern of Anatolia. TGF is 5 km far from Aegean Sea and 80 km south of Çanakkale. Geothermal fluid of TGF has high salinity (EC > 91 mS/cm) and high temperature (reservoir temperature is 173 Â°C). Water samples were taken from February 2012 to April 2013 to determine the physical and chemical (major anioncations and heavy metals) properties of the surface water quality. Furthermore, the soil samples analyzed for physical and chemical properties. All data were evaluated with ArcGIS 10.1 and Aquachem 4.0 software. The results showed that the levels of some major element such as Lityum (4-7 ppm), Barium (1-4 ppm) and Manganese (1-5 ppm) and some heavy metals such as Boron (> 13 ppm) and Strontium (> 14 ppm) in surface water, exceeded national and international limits. Boron and Strontium values of creek ranged from 13 to 27 ppm and from 14 to 154 ppm, respectively. Soil samples contain high concentration of Silisium (> 23800 mg/kg) and Aluminum (> 9000 mg/kg). Particularly, the uncontrolled discharge of geothermal fluid that is rich in terms of toxic elements into soil and surface water resources of the area influences other potential uses of these resources.
Effect of the morphology of aspergillus sojae on pectinase enzyme and the optimization of fermentation conditions
(Izmir Institute of Technology, 2006) Göğüş, Nihan; Tarı, Canan
The control of the morphology of fungi needs great attention for the optimal potential production of the product. For this purpose Aspergillus sojae ATCC 20235, which has no available literature report on the pectinase production, is used as a model in the determination of the optimum regions for maximum polygalacturonase synthesis and biomass formation with desired pellet morphology by using low cost carbon and nitrogen sources. Firstly, a full factorial statistical design, with the factors of, two taxonomically different strains, seven types of seed culture formulations (slants) and two types of fermentation media were used to investigate the effect of these parameters on the polygalacturonase (PG) production. According to statistical analysis, factors of strain types and fermentation media and the interaction between them were found significant on the enzyme activity. Aspergillus sojae in a complex media, inoculated with a seed culture prepared from molasses resulted in maximum PG activity (0.2 U/ml). Then, a two step optimization procedure with four factors (concentrations of maltrin and corn steep liquor (CSL), agitation speed and inoculation ratio) was used to investigate the effect of these parameters on the PG activity, mycelia growth (biomass) and morphology (pellet size) of Aspergillus sojae. According to the results of response surface methodology (RSM), concentrations of maltrin, CSL and agitation speed were significant (p<0.05) on both PG synthesis and biomass formation. As a result, maximum PG activity (13.5 U/ml) was achievable at high maltrin (120 g/l), low CSL (0 g/l), high agitation speed (350 rpm) and high inoculation ratio (2x107 total spore). The diameter of pellets ranged between 0.05-0.63 cm. The second optimization step improved the PG activity by 74 % and the biomass by 40 %. Furthermore characterization of the enzyme with respect to its optimum pH and temperature and the effect of these on the stability were considered. Determination of the thermal inactivation constant with its inactivation energy and the substrate specificity constant were estimated.
Environmental effects of geothermal applications case study: Balçova geothermal field
(Izmir Institute of Technology, 2003) Çakın, Ayça; Gökçen Akkurt, Gülden
Direct application of geothermal energy can involve a wide variety of end uses, such asspace heating and cooling, industrial applications, greenhouses, fish farming, and health spas. It uses mostly existing technology and straightforward engineering. The technology, reliability, economics and environmental acceptability of direct use applications of geothermal energy have been demonstrated throughout the world.The use of geothermal energy is the minimum waste forming type of energy in the world. Geothermal energy is also considered cheap, sustainable and environmentally friendly when compared to the other energy resources.Turkey has abundant geothermal resources because of its location. In particular, İzmir-Balçova district heating system is one example of the high temperature district heating applications in Turkey exhibiting high geothermal potential.The objective of the Thesis is threefold, namely: (a) to determine the negative and positive environmental effects of Balçova Geothermal District Heating System, (b) to find out sources of contamination if pollution exists (c) to offer a solution to protect the public health.Contamination may occur in Balçova Geothermal Field in either water phase or soil phase. Therefore, a sampling program was developed in order to monitor the alterations in water. The sampling points were chosen in a way that Balçova District Heating System production wells, groundwater wells, and the irrigation points could all be monitored.In order to investigate the contamination of the region, several parameters including physical properties such as temperature, electrical conductivity, total dissolved solids, alkalinity; non-metallic constituents such as ammonia, boron, chloride, silica, sulfate; and metals and semi metals such as calcium, magnesium, sodium, potassium etc. were determined.The results of this study showed that all of the samples had bicarbonate alkalinity. The concentrations of the parameters were not constant during the monitoring study. This may be because of the nature of geothermal fluid. During the studying period, concentrations of many heavy metals were below the limit of detection of atomic spectrometric techniques used in the study. Wells T and I did not seem to be suitable for drinking and irrigation water, respectively.In order to determine the effects of Balçova District Heating System on physical environment, noise measurements were conducted. The results of noise measurements have shown higher values than the acceptable limits of Noise Control Regulation.
Environmental impact and capacity analysis of renewable energy resources: Case study of wind energy in Turkey
(Izmir Institute of Technology, 2016-08) Değirmenci, Sinem; Bingöl, Ferhat; Sofuoğlu, Sait Cemil
The majority of electricity in Turkey is generated from coal and natural gas; however, renewable energy, especially wind power, is a promising energy source for Turkey. Development of new wind energy project requires complex planning process involving many social, technical, economic, environmental, political concerns and different agents such as investors, utilities, governmental agencies or social groups. To address the proper site selection, a Geographic Information System (GIS) based Multi- Criteria Decision-Making (MCDM) method has been used in previous studies. The aim of this study is to develop a GIS-based multi-criteria decision making application which can be updated by the changing regulations to identify potential sites for wind power plants in Turkey. A variety of constraints and factors were identified based on a literature review, regulations and gathered from variety of agencies. After excluding of infeasible sites, pairwise comparisons was carried out using analytic hierarchy process (AHP) as MCDM method by the study group to estimate relative importance of the criteria. The suitability map obtained from MCDM analysis was divided into four classes from the low suitable to extremely suitable area. As a final stage, decision making was carried out with the objectives by environmental impact approach. The output of this study can be used by energy planners to estimate the extent that wind energy can be developed based on public perception, administrative and environmental aspects.
Estimation of low sucrose concentrations and classification of bacteria concentrations with machine learning on spectroscopic data
(Izmir Institute of Technology, 2019-06) Mezgil, Bahadır; Baştanlar, Yalın
Spectroscopy can be used to identify elements. In a similar way, there are recent studies that use optical spectroscopy to measure the material concentrations in chemical solutions. In this study, we employ machine learning techniques on collected ultraviolet-visible spectra to estimate the level of sucrose concentrations in solutions and to classify bacteria concentrations. Some metal nanoparticles are very sensitive to refraction index changes in the environment and this helps to detect small refraction index changes in the solution. In our study, gold nanoparticles are used and we benefited from this property to estimate sucrose concentrations. The samples in different low sucrose concentration solutions are obtained by mixing the sucrose measured with precision scales with pure water and then the UV-Vis spectrum of each sample is measured. For the bacteria concentration solutions, spectra for six different bacteria concentrations are captured. Spectra of the same solutions are also captured before adding the bacteria. For each of these solutions, four sets are prepared where gold nanoparticles are not grown (minute 0) and grown for 4 minutes, 10 minutes and 12 minutes. After the dataset preparation, these spectrum measurements are transferred into MATLAB environment as sucrose concentration dataset and bacteria solution dataset. Then the necessary preprocessing steps are performed in order to get the most informative and distinguishing information from these datasets. The raw measurement values and processed spectrum measurements are trained with shallow Artificial Neural Networks (ANN) on MATLAB Deep Learning Toolbox and Support Vector Machine (SVM) on MATLAB Statistics and Machine Learning Toolbox. When the results of the conducted machine learning experiments are examined, success rate is promising for the estimation of sucrose concentrations and very high for classification of bacteria concentrations in pure water solution.
Evaluation of architectural heritage characteristics of Bekirbeyler House in Kula, Manisa
(Izmir Institute of Technology, 2013) Kırtaş, Esra; Turan, Mine
Bekirbeyler House is located in Cami-i Cedit district of Kula, Manisa. It stands out with its large scale, well preserved plan organization, authentic elements such as projections, cupboards, windows, platforms, and decoration program. The aim of the study is to assess the architectural heritage characteristics of Bekirbeyler House, considering the data collected from the house through site survey, and archive and historical research. It is important to understand the plan layout, spatial relations, architectural elements and construction technique of the house so that the characteristics that makes the house special among the other Kula houses and Ottoman houses in Anatolia can be made clear. For this reason; firstly, field survey and archive research were completed. The field survey consists of sketching, taking simple measurements such as width, length and height of spaces and some major elements, and photographing with pictorial and rectification aims. The archive survey includes research at Kula Municipality and Regional Conservation Board. The data gathered was classified under two main thematic headings: spatial and constructional. Formation of conventional measured drawings based on simple measurements, mapping, single image rectification and thematic table preparation were the techniques used. The characteristics of the houses in Kula Urban Site and Ottoman houses in Anatolia, as revealed in historical research, were compared with Bekirbeyler House. As a result of the study, the unique, rare and authentic features of Bekirbeyler House were documented and defined. The building is unique in terms of its large scale and it has sustained majority of its architectural characteristics. Today, because of abandonment and lack of funding for restoration, the building is in danger of being lost. This study will be a source of data for the restoration design of the building and will contribute to the conservation of the buildingâ€™s specific heritage features.
Exposure and risk assessment for arsenic in Simav plain by ingestion of edible crops
(Izmir Institute of Technology, 2017-07) Terzi, Begüm; Sofuoğlu, Sait Cemil; Gündüz, Orhan
Ingestion is the main route of exposure to arsenic. The pathways of concern are ingestion of drinking water and arsenic-accumulating plants. Simav plain has been shown to have the natural arsenic conamination of waters and soil. However, foodstuff was not made a subject of investigation. In this study, arsenic exposure via ingestion of edible plants cultivated in Simav plain was investigated based on the modeling of the measured soil concentrations and data collected from the literature, which were for bioconcentration factors, plant consumption rates, background arsenic concentrations in plants, plant root depths, and body weights. Eighteen plant species, which are bean, broccoli, cabbage, carrot, cauliflower, corn, cucumber, eggplant, garlic, lettuce, okra, onion, potato, radish, spinach, sunflower seed, tomato, and wheat were studied. Chronic-toxic and carcinogenic risks associated with the consumption contaminated foodstuff were assessed with two approaches: scenario based point estimates (deterministic approach) and population based estimates (probabilistic approach). Monte Carlo simulation was used to determine chronic-toxic and carcinogenic risks via ingestion of edible plants probabilistically. Wheat was found as the plant variety with the highest non-carcinogenic and carcinogenic risks which was followed by potato, tomato, cucumber, corn, cabbage, eggplant, and onion. Non-carcinogenic risk levels for broccoli, cauliflower, garlic, and radish were below the threshold level. However, their carcinogenic risk levels were considerable. The risk levels estimated in this study are exceptionally high, indicating consumption of the plants cultivated in Simav may pose significant chronic-toxic and carcinogenic health risks.
Groundwater quality assessment in Torbalı Region
(Izmir Institute of Technology, 2002) Kırer, Tuğba; Tayfur, Gökmen
Groundwater is an important source of irrigation, drinking water and other human activities. With the growth in population, agricultural and industrial activities and the groundwater usage have increased dramatically. However, not only the groundwater use, but also has the level of contamination in groundwater increased. In TorbalI region, drinking water and irrigation water are supplied from wells which are drilled mostly without permission. Excessive abuse of fertilizers, and pesticides in agricultural activities and industries cause to contaminate the groundwater. In order to investigate the quality of the groundwater in this regIOn, sampling locations were determined taking the geology and industry of the region into account. The samples were collected monthly for ten months. In this study, water quality parameters which are pH, temperature, electrical conductivity, calcium, magnesium, potassium, sodium, chloride, alkalinity, nitrate, nitrite, ammonia, copper, chromium, cadmium, lead, zinc, chemical oxygen demand (COD), and cyanide were examined to determine the groundwater quality and relationship between the parameters and the sources of contamination. The samples were classified as hard water. All of the samples had bicarbonate alkalinity. The study revealed the existence of agricultural contamination. Nitrate concentrations of the groundwater samples increased in summer and the concentrations of nitrate were higher than the permissible limit in some of the wells. Heavy metal contamination was not detected in the region. The concentrations of the parameters were not constant during the monitoring study. This may be because the leachate of wastewaters which are discharged suddenly and discontinuously.
Identification of long non-coding RNAs that regulate apoptosis in human
(Izmir Institute of Technology, 2015-12) Ahmadov, Ulvi; Akgül, Bünyamin
Apoptosis is essential for cellular homeostasis and normal development. Aberrant apoptosis (too much or too less) is associated with many important diseases such as autoimmune diseases and cancer. Studies have led to the identification of a number of proteins and microRNAs involved in the regulation of apoptosis. However, the role of long non-coding RNAs (lncRNAs) is still unclear. In this study, two cancer therapeutics drugs, cisplatin and doxorubicin, and two ligands, Fas mAb and TNF-alpha, were used in identification of differentially expressed pathway-drug specific and/or global lncRNAs in apoptotic HeLa cells. Following dose-kinetics experiments the level of apoptosis was measured by Flow Cytometry and was further verified by Fluorescence Microscopy and Western Blotting via measurement of Caspase 3, 8 and 9 protein levels. Three replicates of total RNAs (control and drug/ligand-treated cells) were sent to deepsequencing using the Illumina platform. The resulting reads matched to the human genome greater than 95%. Under our experimental setting, treatments with cisplatin, doxorubicin, Fas mAb and TNF-alpha led to the differential expression of 1644, 506, 584 and 807 lncRNAs, respectively (2-fold or higher, P < 0.01). Two of identified lncRNAs common for all inducers was in antisense position to TRAIL-R2 receptor and FasR associated factor which play directly in apoptosis. Results suggest that many lncRNAs are differentially expressed upon treatment with the indicated agents. Functional characterization of candidates might provide an interesting insight into regulation of apoptosis.
Impact resistance of steel fiber reinforced concrete slabs
(Izmir Institute of Technology, 2015-07) Yaşayanlar, Süleyman; Saatcı, Selçuk
As rare as it may seem, impact loads can act on a structure in its lifespan. For structures such as nuclear energy facilities, industrial facilities, and military buildings design for impact loads may be required. Steel fibers are increasingly used in the design and construction of such reinforced concrete structures. However, studies on the effect of steel fibers on the impact resistance of reinforced concrete structures are rare in the literature. This study investigates the global behavior of reinforced concrete slabs with different ratios of steel fibers under static and impact loading. 10 steel fiber reinforced concrete slabs with dimensions of 2150x2150x150 mm were tested with varying steel fiber volume ratios of 0.5 %, 1.0 % and 1.5 %. Specimens were manufactured as twins, as one to be tested under static loading and one to be tested under impact loading. Static tests were carried out by applying a static load at the midpoint with a hydraulic jack, whereas impact tests were applied through free falling drop-weights. Observed behavior and collected data were compared with companion studies of Batarlar (2013) and Arsan (2014), as they have used the same test setup with different parameters. As a result, it was seen that even steel a fiber addition of 0.5 % in volume was sufficient to provide a ductile behavior both under static and impact loading. Steel fibers significantly enhanced the impact behavior by increasing the strength and resiliency of the specimens.
Impacts of partical plans on urban growth,case study: Güzelbahçe-Seferihisar axis
(Izmir Institute of Technology, 1999) Buğu, Soner; Arkon, Cemal
In recent years, partial plans become intensive especially, in fringe areas of metropolitan cities in our country. The thesis research alleges that, the partial plans created a new form of urban growth and this form of growth, which is named as "urban sprawl", caused many socio-economic and spatial problems in our country. For these reasons, this study mainly aims; to evaluate the implementation process of the partial plans by determining the position of the partial plans in the existing legal system; to determine the existing and potential urban problems which the partial plans have caused; and to indicate the changes in landownership pattern within the boundaries of partial plans.This study indicated that, the partial plans, which are carried out outside the boundary of macro plans of the city, create many urban problems on urban growth process and cause unplanned and haphazard growth of the city. These problems are mainly; leapfrog and haphazard urban growth, formation of a dispersed urban grain , integration problems of the scattered urban uses, undesired city macroforms and socio-economic problems. Furthermore, this study also indicated that, there are not sufficient legal arrangements regarding the partial plans in the existing legal system, and these plans are used as an instrument for the benefit of land speculators.The methodology used in the thesis research may said to be composed of literature surveys and evaluation of the knowledge and documents gathered from the related public institutions and observations made in a case study area.Key Words: Partial Plan Urban Sprawl, Scattered Urban Fabric, Haphazard Urban Growth, Urban - Rural Fringe, Land Speculation.
Inhalation exposure to polychlorinated biphenyls in Izmir
(Izmir Institute of Technology, 2022-06) Edebali, Özge; Sofuoğlu, Sait Cemil; Sofuoğlu, Aysun
Polychlorinated biphenyls (PCBs) are chemicals that are classified as hazardous air pollutants with carcinogenic and chronic-toxic effects on human health. People may be exposed to these chemicals indoors and outdoors via inhalation of indoor and outdoor air. Their production and use were banned worldwide with the Stockholm Convention. Since the Turkish government became an official signatory to the Stockholm Convention in year of 2010, the determination of persistent organic pollutants (POPs) in environmental compartments in Türkiye has gained importance. PCBs are still present in the environment because they are found in materials such as those used in heat transfer, electrical, and hydraulic systems manufactured before the ban due to their persistence to degradation in environment. Industrial processes have an important effect on their environmental concentrations due to unintentional emissions. Therefore, they are still present in air and investigations show that industrial and urban areas have higher levels. The aim of this study was to measure concentrations of PCB compounds in indoor-outdoor air samples collected at homes and schools, and to estimate exposure and associated carcinogenic health risks. Samples were collected at randomly selected sites in urban, semi-urban, and rural areas with polyurethane foam – passive samplers. Samples were analyzed by using gas chromatography–mass spectrometry after Soxhlet extraction. The estimated carcinogenic risks even at the 95th percentile were calculated below the acceptable risk level (10-6), indicating that the population carcinogenic risk associated with inhalation of gas-phase PCBs is not considerable. However, aggregate risks that could be estimated by addition of other plausible exposure pathways would drive the levels above the acceptable level.
The investigation of seawater intrusion of coastal aquifer in Karareis (Karaburun Peninsula)
(Izmir Institute of Technology, 2016-11) Mansour, Ahmed Y. S.; Baba, Alper; Gündüz, Orhan
Seawater intrusion is a major problem to freshwater resources especially in coastal areas where fresh groundwater is surrounded and could easily be influenced by seawater. This study presents the development of conceptual and numerical model for the coastal aquifer of Karareis region in the western part of Turkey. The study also presents the interpretation and the analysis of the groundwater levels recorded by groundwater data loggers. Groundwater pumping from Karareis aquifer has increased significantly during the summer period to meet the agriculture and domestic water demands. Levels of groundwater were measured at nine locations in Karareis region; also water samples were collected and analyzed for some parameters. For this study SEAWAT code is used to solve the numerical model for the coupled density dependent flow system. The model was calibrated using the average of one-year dataset of collected groundwater levels. Model validation was handled using the average of groundwater levels measured over more one year. Five scenarios were tested to understand the effects of pumping and climate change on groundwater levels and seawater intrusion in the next ten years. The result of analysis demonstrated a high concentration of electrical conductivity and chloride along the coastal part of the study area. As a result of the numerical model, seawater intrusion will extent about 420 m towards the land in the next ten years of increased pumping scenario, while a little change in water level and TDS concentration was recognized in climate change scenario. Results also showed that reducing the pumping from Karareis wells will be necessary to protect the freshwater from contamination by seawater.

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