Waste disposal on karstic terrain: a case study from the ancient marble quarries in Iznik (Nicaea), Turkey

Celalettin Simsek,Ali Bahadir Yavuz,Hakan Elci,Alper Elci,Orhan Gunduz 한국지질과학협의회 2011 Geosciences Journal Vol.15 No.3

This study is conducted in Iznik, a city situated in the Marmara region of Turkey. There are number of ancient marble pits in the area, some of which are used as sewage and solid waste dump sites. This study is aimed at investigating the hydrogeological and hydrogeochemical properties of Iznik plain with special emphasis on these waste sites. In terms of geological features, Derekoy metamorphics are basement rocks that consist of graphite schist, muscovite-quartz schist and marble lenses. Since Iznik marble was used as a natural construction material in the area since in the Roman era, 20 ancient marble quarries in different sizes existed in and around the study area. Wastewater from the city of Iznik and surrounding residential areas was disposed in three of these ancient marble quarries. In terms of hydrogeological features, the Iznik marble and alluvium units constitute the main aquifer system in the study area. Because of the highly fractured structure of the Iznik marble, the wastewater in the quarries was able to move rapidly within the rock. Analyses of groundwater samples revealed that the wastewater flowing in the marble unit discharges eventually into the alluvial unit and thereby affecting groundwater quality around the antique quarries. Based on chemical analyses results, the wastewater was Na-Cl water type and contained high concentrations of Na (3260 mg/l), K (903 mg/l) and Cl (10396 mg/l). Samples from wells down gradient of the wastewater source had comparatively higher Na, K and Cl concentrations

Sorbent Extraction of Some Metal Ions on a Gas Chromatographic Stationary Phase Prior to Their Flame Atomic Absorption Determinations

Soylak, M.,Saracoglu, S.,Elci, L. Korean Chemical Society 2003 Bulletin of the Korean Chemical Society Vol.24 No.5

An enrichment/separation system for atomic absorption spectrometric determinations of Cu(Ⅱ), Fe(Ⅲ), Ni(Ⅱ) and Co(Ⅱ) has been established. The procedure is based on the adsorption of the analytes as calmagite chelates on Chromosorb-102. The effects of some parameters including pH, amount of ligand, salt matrix, flow rates of sample and eluent solutions were investigated. Under optimized conditions, the relative standard deviation of the combined method of sample treatment, preconcentration and determination with FAAS (N=5) is generally lower than 5%. The limit of detection (3σ) was between 6.0-112.9 ㎍/L. The results were used for preconcentration of analytes from some sodium and ammonium salt.

Diagnostic Utility of Osteocalcin, Undercarboxylated Osteocalcin, and Alkaline Phosphatase for Osteoporosis in Premenopausal and Postmenopausal Women

Sacide Atalay,Abdullah Elci,Huseyin Kayadibi,Can B Onder,Nurettin Aka 대한진단검사의학회 2012 Annals of Laboratory Medicine Vol.32 No.1

Background: We aimed to investigate the diagnostic utility of osteocalcin (OC), undercarboxylated osteocalcin (ucOC), and alkaline phosphatase (ALP) in pre- and postmenopausal women for femoral neck, L1-4, and L2-4 bone mineral density (BMD) values by taking into consideration their age, body mass index (BMI), and menopausal status. Methods: Premenopausal (N=40) and postmenopausal cases (N=42) were classified as 25-34 or 35-45 yr of age and within the first 5 yr or 5 yr or more after the onset of menopause, respectively. Results: Among the groups, statistical differences were found for age, BMI, OC, ucOC, ALP, femoral neck BMD, L1-4 BMD, and L2-4 BMD. The highest serum OC, ucOC, and ALP levels were observed in cases within the first 5 yr after the onset of menopause, probably due to a more rapid bone turnover rate. The best predictors for the femoral neck osteoporosis were ALP, OC, and calcium (areas under the ROC curve [AUC]=0.882, 0.829, and 0.761, respectively), and those for L1-4 and L2-4 osteoporosis were OC, ALP, and ucOC (AUC=0.949, 0.873, and 0.845; and 0.866, 0.819, and 0.814, respectively). Multiple logistic regression analysis revealed that the most discriminative parameter for osteoporosis was OC. Conclusions: These results indicate that serum OC levels, with or without ucOC and ALP, may be useful to monitor follow-up changes that currently cannot be assessed with BMD and to diagnose femoral neck, L1-4 spine, and L2-4 spine osteoporosis. Background: We aimed to investigate the diagnostic utility of osteocalcin (OC), undercarboxylated osteocalcin (ucOC), and alkaline phosphatase (ALP) in pre- and postmenopausal women for femoral neck, L1-4, and L2-4 bone mineral density (BMD) values by taking into consideration their age, body mass index (BMI), and menopausal status. Methods: Premenopausal (N=40) and postmenopausal cases (N=42) were classified as 25-34 or 35-45 yr of age and within the first 5 yr or 5 yr or more after the onset of menopause, respectively. Results: Among the groups, statistical differences were found for age, BMI, OC, ucOC, ALP, femoral neck BMD, L1-4 BMD, and L2-4 BMD. The highest serum OC, ucOC, and ALP levels were observed in cases within the first 5 yr after the onset of menopause, probably due to a more rapid bone turnover rate. The best predictors for the femoral neck osteoporosis were ALP, OC, and calcium (areas under the ROC curve [AUC]=0.882, 0.829, and 0.761, respectively), and those for L1-4 and L2-4 osteoporosis were OC, ALP, and ucOC (AUC=0.949, 0.873, and 0.845; and 0.866, 0.819, and 0.814, respectively). Multiple logistic regression analysis revealed that the most discriminative parameter for osteoporosis was OC. Conclusions: These results indicate that serum OC levels, with or without ucOC and ALP, may be useful to monitor follow-up changes that currently cannot be assessed with BMD and to diagnose femoral neck, L1-4 spine, and L2-4 spine osteoporosis.

Longitudinal Relationship between Physical Activity and Cardiometabolic Factors in Overweight and Obese Adults

Jina Choo,Okan U Elci,Kyeongra Yang,Melanie W. Turk,Mindi A. Styn,Susan M. Sereika,Edvin Music,Lora E. Burke 한국간호과학회 2009 한국간호과학회 학술대회 Vol.2009 No.10

Determination of Trace Metals in Waters by FAAS after Enrichment as Metal-HMDTC Complexes Using Solid Phase Extraction

Tokalioglu, Serife,Kartal, Senol,Elci, Latif Korean Chemical Society 2002 Bulletin of the Korean Chemical Society Vol.23 No.5

A method has been described for the determination of Cu(Ⅱ), Pb(Ⅱ), Ni(Ⅱ), Cd(Ⅱ), Mn(Ⅱ) and Fe(Ⅲ) by flame atomic absorption spectrometry (FAAS) after preconcentration on Amberlite XAD-16 resin, using hexamethyleneammonium-hexamethylenedithiocarbamate (HMA-HMDTC) as a chelating agent, and NH3/NH4Cl buffer solution (pH 9). Influences of various analytical parameters such as pH, concentration of nitric acid, amount of analytes, diverse ions and sample volume were investigated. The relative standard deviation (RSD) and the detection limit (LOD) were found in the range of 0.8-2.9% and 0.006-0.277 ㎍/mL,respectively. Recoveries obtained by the column method were quantitative ( >95%) at optimum conditions.The method was applied to the determination of some metal ions in seawater and wastewater samples. A high preconcentration factor (about 150 for seawater and 75 for wastewater samples) and simplicity are the main advantages of this suggested method.

Reticulated Vitreous Carbon Foams from Sucrose: Promising Materials for Bone Tissue Engineering Applications

Natalia Terán Acuña,Viviana Güiza-Argüello,Elcy Córdoba-Tuta 한국고분자학회 2020 Macromolecular Research Vol.28 No.10

Reticulated vitreous carbon (RVC) foams have shown favorable biocompatibility and the potential to support osteoblastic adhesion. In this work, RVC foams were fabricated via template route, using a low-cost sucrose-based resin. The effect of several process parameters, such as template porosity (cell size between 500 and 1400 μm) and carbonization conditions, were studied. The resulting RVC foams displayed highly interconnected porosity (˃ 85%) with controllable cell size, bone-like morphology, and compressive strength of 0.06-0.26 MPa. The results suggested that the decrease in the cell size of the sacrificial sponge, the increase in the thickness of the sponge cell ligaments, and the carbonization temperature of 1500 °C, contributed to the enhancement of the mechanical response of the fabricated scaffolds. Finally, cytotoxicity and cell adhesion assays were carried out using normal human osteoblasts as a preliminary assessment of the cytocompatibility of the synthesized RVC foams. Although the mechanical strength of these foams could still be improved, these results contribute towards the development of low-cost bioactive scaffolds that resemble the morphological properties of the trabecular bone.