Prioritization methodology of dangerous substances for water quality monitoring with scarce data

Monitoring and control of dangerous substances discharged into receiving waters have attracted more attention lately. Since it is not possible to analyze every single substance, a prioritization methodology is needed for the selection of those to be monitored. Existing well-developed models require significant amount of data for reliable outcomes. This paper presents a methodology to prioritize the dangerous substances having adverse effects on freshwaters in Turkey, where data are scarce. Such a methodology will also serve as a solid model for other countries with limited background data. The adopted methodology enabled the elimination of chemicals to generate a candidate list composed of 608 substances among more than 5000 substances. Further screening and prioritization were conducted using different assessment methods (i.e., Total Hazard Value, Total Impact Value, Combined Monitoring-based, and Modelling-based Priority Setting) to obtain a proposed Final Candidate Specific Pollutants List of 150 dangerous substances. The proposed Candidate National Pollutant List of Turkey was established by combining 45 priority pollutants of the European Union with a list of candidate specific pollutants. According to the outcomes of this study, monitoring and controlling of 195 dangerous substances in freshwaters are recommended. Further detailed studies should be conducted in order to observe the actual levels of these dangerous substances in freshwaters followed by a review of the monitoring list accordingly. Moreover, further revisions might be required in the proposed list due to some possible versatile conditions in terms of sampling points (i.e., change in the location of industries).     

Buckling lengths of irregular frame columns

In several design codes and specifications, simplified formulae and diagrams are given for determining the buckling lengths of frame columns. It is shown that these formulae may yield rather erroneous results, especially for irregular frames. This is due to the fact that the code formulae utilise only local stiffness distributions. In this paper, a simplified procedure for determining approximate values for the buckling loads of both regular and irregular frames is developed. The procedure utilises lateral load analysis of frames and yields errors on the order of 5%, which may be considered suitable for design purposes. The proposed procedure is applied to several numerical examples and it is shown that all the errors are in the acceptable range and on the safe side.     

Screening of free radical scavenging capacity and antioxidant activities of Rosmarinus officinalis extracts with focus on location and harvesting times

Methanolic extracts from the leaves of Rosmarinus officinalis (rosemary) harvested from different locations of Turkey at four different times of the year were analyzed by HPLC, and their radical scavenging capacities and antioxidant activities were studied by various assays. The amounts of carnosol, carnosic acid and rosmarinic acid, active constituents of rosemary, varied in different geographical regions of growth, and also showed a seasonal variation. The levels of the constituents were higher in the warm months of June 2004 and September 2004. The antioxidant activities of 12 extracts were determined by in vitro DPPH radical scavenging activity, by Trolox equivalent antioxidant capacity (TEAC), and by reversing H₂O₂-induced erythrocyte membrane lipid peroxidation (EMLP). The two antioxidant enzyme activities of human erythrocyte, namely superoxide dismutase (SOD) and catalase (CAT), after in vitro incubation with the extracts, were also examined in order to see whether the observed effects are related to altered enzymatic efficiency. The resulting values were correlated with active metabolite and total phenol contents of the extracts. The results indicated that the plants harvested in September possessing higher levels of active constituent had superior antioxidant capacities compared to the ones collected at other times. With respect to the location, plants harvested from the Izmir region had lower total phenol and active constituent levels resulting in poorer antioxidant activity.     

Improving reinforcement learning by using sequence trees

This paper proposes a novel approach to discover options in the form of stochastic conditionally terminating sequences; it shows how such sequences can be integrated into the reinforcement learning framework to improve the learning performance. The method utilizes stored histories of possible optimal policies and constructs a specialized tree structure during the learning process. The constructed tree facilitates the process of identifying frequently used action sequences together with states that are visited during the execution of such sequences. The tree is constantly updated and used to implicitly run corresponding options. The effectiveness of the method is demonstrated empirically by conducting extensive experiments on various domains with different properties.     

Research on the normality of the plastic strain vector to the yield surface in RC sections

In this study, the normality condition of the plastic strain vector to the yield surface utilized for elastic-perfectly plastic materials is investigated for reinforced concrete (RC) sections. If the plastic strain vector can be assumed outward normal to the yield surface in RC sections under combined biaxial bending and axial load, the components of the vector can be expressed by a single parameter. Thus, the material nonlinearity can be simplified through the extended plastic hinge concept based on the normality condition. In this study the normality of the plastic strain vector is verified via numerical examples in symmetrically reinforced rectangular and circular RC sections subjected to biaxial bending and axial load for various configurations of longitudinal reinforcement.     

Role of surgical treatment in 70 patients with vertebral metastasis causing cord or root compression

Spinal metastasis plays an important role in the survival rate and general condition of cancer patients. In this paper, we present 70 patients with metastatic spinal tumors, diagnosed and surgically treated in the Departments of Neurosurgery and Orthopedics of Ankara Numune State Hospital between 1984 and 1993. Our clinical observations suggest that the survival rate is influenced by the type of the primary lesion, pathology, and the patient's preoperative physical and neurological status.     

Anti-bacterial activity of the fluid contents of spermatoceles and epididymal cysts

OBJECTIVE: To show that the fluids obtained from spermatoceles and epididymal cysts are not infected, even though they may be present for long periods, and that these fluids have bactericidal activity. MATERIALS AND METHODS: Sixteen patients, 13 with a spermatocele and three with an epididymal cyst, were included in the study. Protein, glucose, chloride, inorganic phosphorus, calcium and magnesium contents were measured and cultures of the fluids were carried out. Bactericidal activity against the Escherichia coli NTCC 10418 clone was tested in different dilutions. RESULTS: Biochemical analysis showed that the protein, glucose and ionic content of the fluids was lower than that of serum, except for chloride. Microbiological cultures were negative for all samples. A significant bactericidal effect was obtained with 1/1 dilution and no reproduction was seen with this dilution. CONCLUSION: These findings indicate that the fluids within spermatoceles and epididymal cysts do not become infected under normal circumstances.     

Combining differential quadrature method with simulation technique to solve non‐linear differential equations

Nowadays, most of the ordinary differential equations (ODEs) can be solved by modelica‐based approaches, such as Matlab/Simulink, Dymola and LabView, which use simulation technique (ST). However, these kinds of approaches restrict the users in the enforcement of conditions at any instant of the time domain. This limitation is one of the most important drawbacks of the ST. Another method of solution, differential quadrature method (DQM), leads to very accurate results using only a few grids on the domain. On the other hand, DQM is not flexible for the solution of non‐linear ODEs and it is not so easy to impose multiple conditions on the same location. For these reasons, the author aims to eliminate the mentioned disadvantages of the simulation technique (ST) and DQM using favorable characteristics of each method in the other. This work aims to show how the combining method (CM) works simply by solving some non‐linear problems and how the CM gives more accurate results compared with those of other methods. Copyright © 2008 John Wiley & Sons, Ltd.