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WOS: 000428760800037 PubMed ID: 28160191 Purpose To evaluate possible risk factors for multiple retinal tears in patients with acute posterior vitreous detachment. Materials and methods Three hundred and seventy-six consecutive patients presenting with symptoms of floaters and/or flashes were examined. The associations of retinal tears with the duration of symptoms, multiple floaters, flashing, a family history of retinal detachment, peripheral retinal degeneration, lens status, myopia, tobacco dust, and retinal or vitreous hemorrhage were analyzed. Results Fifty-four (14.4%) of the 376 patients had 71 initial retinal tears. Forty of the 54 eyes had one retinal tear, and 14 eyes had multiple retinal tears. The presence of retinal or vitreous hemorrhage increased the risk of multiple retinal tears 6.1 times using univariate analysis and 7.0 times using multivariate analysis. Conclusion Unrecognized retinal tears in patients with acute posterior vitreous detachment can cause subsequent retinal detachment. It is therefore important to consider multiple retinal tears, especially in patients with retinal or vitreous hemorrhage.

WOS: 000343129800006, This study proposes the use of multi-layer perceptron neural networks (MLPNN) to invert dispersion curves obtained via multi-channel analysis of surface waves (MASW) for shear S-wave velocity profile. The dispersion curve used in inversion includes the fundamental-mode dispersion data. In order to investigate the applicability and performance of the proposed MLPNN algorithm, test studies were performed using both synthetic and field examples. Gaussian random noise with a standard deviation of 4 and 8% was added to the noise-free test data to make the synthetic test more realistic. The model parameters, such as S-wave velocities and thicknesses of the synthetic layered-earth model, were obtained for different S/N ratios and noise-free data. The field survey was performed over the natural gas pipeline, located in the Germencik district of AydA +/- n city, western Turkey. The results show that depth, velocity, and location of the embedded natural gas pipe are successfully estimated with reasonably good approximation.

WOS: 000391468200036, In this work, the effects of magnetic field, hydrostatic pressure and temperature on the linear and nonlinear optical properties in GaAs/AlxGa1-xAs symmetric double semi-V-shaped quantum well (DSVQWs) have been theoretically studied by using the compact-density matrix approach and the effective-mass approximation. Our numerical results show that the optical characteristic of these structures is strongly affected by the magnetic field, hydrostatic pressure and temperature.

WOS: 000303405900013, PubMed ID: 21792732, Introduction The reliability and validity of Turkish version of Childhood Asthma Control Test (C-ACT). Purpose The management of asthma is an important as well as difficult issue of physician's daily practice particularly in busy clinical settings. C-ACT was created to identify asthma control levels in children aged 4-11 years. Our aim was to evaluate the reliability, validity and responsiveness of C-ACT in a Turkish sample of children with asthma. Method In this multicenter study, 368 children were enrolled. C-ACT was completed every month by parents and patients who were evaluated in 3 visits within 2 month intervals. At each visit, physicians interpret the control level and decided for the treatment step as established in GINA guidelines. Results The internal consistency reliability of the Turkish version of C-ACT (C-ACT1 to C-ACT5) was found to be 0.82, 0.83, 0.82, 0.82 and 0.80, respectively (reliability statistics, Cronbach's alpha). Test-retest reliability was 0.71. There was significant correlation between C-ACT and physician's assessment of asthma control at visit 1 (r = 0.65, P < 0.001). Conclusions Turkish version of C-ACT is an accurate and reliable tool to evaluate asthma control in children aged 4-11 years. Its widespread use may facilitate appropriate assessment of asthma control and may lead to decrease the number of uncontrolled patients.

WOS: 000292828500003, By using the compact-density matrix approach, the effect of a nonresonant intense laser field on the linear and nonlinear optical absorptions based on intersubband transitions and the refractive index changes in an asymmetric semiconductor quantum well have been presented. Our results show that the peak position of the absorption coefficient is sensitive to intense laser field, the absorption maximum shifts towards lower energies for increasing intense laser field value. Also we observe as the intense laser field strength increases, the total refractive index change has been increased in magnitude and also shifted towards lower energies. The results indicate that linear and nonlinear optical properties of the low dimensional semiconductor heterostructures can be adjusted in a desired energy range by using intense laser field., TUBITAK (COST) [109T650]; COLCIENCIAS; CODI-Universidad de Antioquia; Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia; Excellence Center for Novel Materials/COLCIENCIAS [043-2005], This work supported by TUBITAK (COST) 109T650 and this research was partially supported by Colombian Agencies: COLCIENCIAS, CODI-Universidad de Antioquia (Estrategia de Sostenibilidad Grupo de Mate-ria Condensada-UdeA, 2010-2011), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project 2010-2011), and the Excellence Center for Novel Materials/COLCIENCIAS (Contract No. 043-2005).

WOS: 000292513700010, In this work are studied the intense laser effects on the impurity states in GaAs-Ga1- (x) Al (x) As quantum wells under applied electric and magnetic fields. The electric field is taken oriented along the growth direction of the quantum well whereas the magnetic field is considered to be in-plane. The calculations are made within the effective mass and parabolic band approximations. The intense laser effects have been included through the Floquet method by modifying the confinement potential associated to the heterostructure. The results are presented for several configurations of the dimensions of the quantum well, the position of the impurity atom, the applied electric and magnetic fields, and the incident intense laser radiation. The results suggest that for fixed geometry setups in the system, the binding energy is a decreasing function of the electric field intensity while a dual monotonic behavior is detected when it varies with the magnitude of an applied magnetic field, according to the intensity of the laser field radiation., COLCIENCIAS; CODI-Universidad de Antioquia (Estrategia de Sostenibilidad Grupo de Materia Condensada-UdeA); Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia; El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Technologia y la Innovacion Francisco Jose de Caldas [275-2011]; Mexican CONACYT [CB-2008/101777]; CONACYT; The Scientific and Technological Research Council of Turkey (TUBITAK) [TUBITAK 109T650], This research was partially supported by Colombian Agencies: COLCIENCIAS, CODI-Universidad de Antioquia (Estrategia de Sostenibilidad Grupo de Materia Condensada-UdeA, 2009-2010, 2010-2011), Facultad de Ciencias Exactas y Naturales-Universidad de Antioquia (CAD-exclusive dedication project 2010-2011), and by "El Patrimonio Autonomo Fondo Nacional de Financiamiento para la Ciencia, la Technologia y la Innovacion Francisco Jose de Caldas" Contract RC - No. 275-2011. The work was developed with the help of CENAPAD-SP, Brazil. MEMR acknowledges support from Mexican CONACYT through research grant CB-2008/101777. CAD and MEMR are indebted to COLCIENCIAS and CONACYT for support under the bilateral project "Estudio de propiedades opticas y electronicas en nanoestructuras y sistemas semi-conductores de baja dimension". The authors are grateful to The Scientific and Technological Research Council of Turkey (TUBITAK) for a research grant (TUBITAK 109T650).

WOS: 000290040000032, Ulva gigantea (Kutzing) bliding (UGB) obtained from sea inlet of Izmir-Turkey has been studied as a biosorbent for removal of radioactive metals from water. In this study, unmodified UGB and modified UGB with glutaraldehyde (GUGB) characterized by FTIR spectroscopy were used as biosorbents for removal of U(VI) and Th(IV) ions from aqueous solution. Adsorption experiments performed under batch process with initial pH, contact time, adsorbent mass and temperature as variables. In order to determine the adsorption characteristics, Langmuir, Freundlich and Dubinin-Raduschkevich adsorption isotherms were applied to the adsorption data. Adsorption experiments showed that the adsorption isotherms correlated well with the Freundlich model. The sorption followed pseudo-second-order kinetics. The thermodynamic parameters such as variations of Delta HA degrees, Delta GA degrees and Delta SA degrees were estimated as a function of temperature. The thermodynamics of the adsorption of U(VI) and Th(IV) onto UGB and GUGB indicates that the spontaneous and exothermic nature of the process. The results showed that UGB and GUGB were potential for application in removal of U(VI) and Th(IV) from aqueous solution.

WOS: 000256427200002, PubMed ID: 18449592, The aim of the present study was to investigate the habituation rates of the sympathetic skin response (SSR) in sedentary subjects and trained sportsmen. A total of 52 voluntary male students (30 sedentary subjects and 22 trained sportsmen) participated in the experiment. SSR was recorded with the contralateral electrical stimulation of the ulnar nerve (of the upper extremities). In order to initiate the SSRs, 16 square-wave consecutive electrical shock stimuli were presented to each subject over the left ulnar nerve. In 52 subjects, 16 stimuli were applied at random time intervals (20-50 s). In sedentary subjects, the mean amplitude of the SSRs decreased from 4.83 +/- 0.36 mV at the first stimulus, to 0.80 +/- 0.12 mV at the 16th stimulus. In trained sportsmen, the mean amplitude of the SSRs decreased from 3.95 +/- 0.51 mV at the first stimulus, to 0.80 +/- 0.17 mV at the 16th stimulus. In the sedentary subjects, at the S1-S9 stimuli, the mean amplitudes of SSRs were higher than those of trained sportsmen. Depending upon these findings we can say that the trained sportsmen showed a more rapid habituation than sedentary subjects. In these processes, changes of amplitude and latency values reflect changes in amount of neuronal activation. Amplitude reflects the amount of neuronal activation, which is concerned with number of neuronal populations. Neuroplasticity, known as the habituation of the brain, is the adaptation of autonomic nervous system, which can be reflected by SSRs.

WOS: 000186497100020, By using an appropriate coordinate transformation, we have calculated variationally the ground state binding energy of a hydrogenic donor impurity in a quantum well in the presence of crossed electric and magnetic fields which are applied tilted at an angle to the layers. The dependence of the donor impurity binding energy on the well width, on the strength of the electric and magnetic fields, on the impurity position and on the directions of the external fields is discussed.