MCBÜ Açıkerişim Sistemi :: Browsing by Publisher "Elsevier B.V."

Browsing by Publisher "Elsevier B.V."

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P-36 Antidepressant choice in the outpatient department of a psychiatry clinic
(Elsevier B.V., 1996) Işelli I.; Özmen E.
[No abstract available]
Renal functions of enuretic and nonenuretic children: Hypernatriuria and kaliuresis as causes of nocturnal enuresis
(Elsevier B.V., 1997) Vurgun N.; Gumus B.H.; Ece A.; Ari Z.; Tarhan S.; Yeter M.
Objective: The aim of this study was to investigate the pathophysiologic cause(s) of primary nocturnal enuresis. Therefore, electrolyte concentrations of urine specimens were evaluated in the morning, and alterations compared between enuretics and nonenuretics. Methods and Patients: First morning urine specimens of 27 enuretics and 21 nonenuretic subjects fed the same diet were collected, and urinary electrolytes were measured. The urinary Ca/Cr ratio, tubular reabsorption of phosphorus (TRP) and fractional sodium (FE Na%) and potassium excretions (FE K%) were determined for patients and controls. Results: There was no significant difference in the Ca/Cr ratio and TRP between patients and controls, but enuretic patients had significantly higher FE Na% and FE K% values than controls (p < 0.001). There were significant positive correlations between FE Na% and (r = 0.81, p < 0.001) FE K% and the frequency of bedwetting, respectively, among enuretic patients (r = 0.54, p < 0.001). Conclusion: Since Na and K excretion of enuretic patients was higher than in nonenuretics, it can be concluded that there may be a benign hereditary and/or postural renal tubular handling disorder of Na and K in enuretic children.
Geochemistry and petrogenesis of intrusive and extrusive ophiolitic plagiogranites, Central Anatolian Crystalline Complex, Turkey
(Elsevier B.V., 1998) Floyd P.A.; Yaliniz M.K.; Goncuoglu M.C.
Plagiogranites associated with the Sarikaraman ophiolite of the Central Anatolian Crystalline Complex, Turkey, closely resemble other plagiogranites from supra-subduction zone-type ophiolites of Neotethys. The ophiolite is remarkable in displaying a higher proportion of the plagiogranite suite (ca. 10% by volume) than is usually associated with such bodies. The Sarikaraman plagiogranites are represented by intrusive sheets and netvein trondhjemites largely developed at the top of the upper gabbros and as multiphase dykes within the sheeted dyke complex. The plagiogranite dykes are considered to feed extrusive silicified rhyolites associated with the basaltic lavas in the volcanic section of the ophiolite. Field relations suggest that the trondhjemites were probably generated from the roof section of a dynamic and evolving gabbroic magma chamber. Both the deep-seated trondhjemites and the volcanic rhyolites constitute the Sarikaraman plagiogranite suite. Geochemically there is complete overlap between the intrusive trondhjemites and extrusive rhyolites, which are characterised by (MORB-normalized) low HFS element contents with small negative Nb-Ta anomalies and variably enhanced LIL element abundances. Unlike other plagiogranites, however, the Sarikaraman suite is not characterized by consistently low K2O contents; a feature that reflects the variable mobilization of the LIL elements under lower greenschist facies conditions. The REE are uniformly enriched relative to the basic components of the complex, but have similar normalized patterns exhibiting mild light REE depletion. In terms of their origin, the initial or most primitive plagiogranite melts could have been generated by either fractional crystallization (70-85% of clinopyroxene-feldspar ± amphibole) or partial melting (5-15% batch melting) of a gabbroic 'source material', although only the first process can produce most of the range of the plagiogranite compositions. As a group the plagiogranites exhibit some degree of internal variation which can be generated by further fractionation largely dominated by feldspar with minor apatite and amphibole. © 1998 Elsevier Science B.V.
Management of pseudophakic malignant glaucoma and ultrasound biomicroscopic features
(Elsevier B.V., 2009) Seymenoglu R.G.; Baser E.F.
[No abstract available]
Room and low temperature luminescence properties of CaSO4:Dy,Tm codoped with Li
(Elsevier B.V., 2009) Can N.; Karali T.; Wang Y.; Townsend P.D.; Prokic M.; Canimoglu A.
Rare earths, especially Dy or Tm doped CaSO4 phosphors are actively studied. They have high sensitivity, a large dynamic range, thermal stability and ease of preparation. Nevertheless, they can be enhanced by inclusion of lithium and this study reports some effects of lithium co-dopant on the TL and radioluminescence (RL) emissions of two TL phosphors. Addition of Li as a co-dopant ion was made either during chemical preparation of the phosphors, or as a binder component mixed with the basic phosphors matrix during the process of pressing and sintering the TLD pellets.
Cathodoluminescence response from rare earth doped Bi4Ge 3O12
(Elsevier B.V., 2009) Kibar R.; Çetin A.; Tuncer Y.; Uysal S.; Townsend P.D.; Canimoglu A.; Karali T.; Can N.
Room and low temperature cathodoluminescence (CL) of rare earth doped Bi4Ge3O12 (BGO) has been recorded. Luminescence signals noted in the wavelength range (300 - 800 nm) include intrinsic broad emission bands and signals related to Eu3+, Nd3+, and Tm3+. CL measurements made on Bi4Ge3O 12 (BGO) doped with rare earth ions are reported for the temperature range 40 to 300 K with different CL excitation modulation frequencies. Dopant levels used in the present study are 1.1, 0.4, and 0.3 wt% Nd, 0.4 wt% Tm and 3 ppm Eu. All dopant levels exhibited different CL spectra with evidence for lines due to the rare-earth dopants intra-4f transitions. The temperature dependence of the intensity of the emission band is discussed.
Selective laser trabeculoplasty for the treatment of intraocular pressure elevation after intravitreal triamcinolone injection
(Elsevier B.V., 2009) Baser E.; Seymenoglu R.
[No abstract available]
How wireless sensor networks can benefit from Brain Emotional learning Based Intelligent Controller (BELBIC)
(Elsevier B.V., 2011) Kalayci T.E.; Bahrepour M.; Meratnia N.; Havinga P.J.M.
Wireless sensor networks (WSNs) are composed of small sensing and actuating devices that collaboratively monitor a phenomena, process and reason about sensor measurements, and provide adequate feedback or take actions. One of WSNs tasks is event detection, in which occurrence of events of interest is detected in situ whenever and wherever they occur. Some examples of these events include environmental (e.g. fire), personal (e.g. activities), and data-related (e.g. outlier) events. Simply speaking, event detection is a classification process, in which membership of data measurements to each event class is determined. Neural network is one of the classifiers that have often been used for detecting events with known patterns. One of the techniques to maximise the neural network performance during classification process is enabling a learning process. Through this learning process, neural network can learn from errors generated in each round of classification to gradually improve its performance. In this paper we investigate applicability of Brain Emotional Based Intelligent Controller (BELBIC) to improve neural network performance. Empirical results show that incorporating the BELBIC with neural networks improves the accuracy of event detection in many circumstances. © 2011 Published by Elsevier Ltd.
Radioluminescence of SrAl2O4:Ln3+ (Ln = Eu, Sm, Dy) phosphor ceramic
(Elsevier B.V., 2011) Ayvacikli M.; Ege A.; Can N.
Phosphors for radiation detection require efficient energy transfer from the ionization track to the luminescent centers. In this work, the radioluminescence (RL) spectra of SrAl2O4 phosphor ceramics doped with individual trivalent rare earth element (REE) ions (Sm, Eu and Dy) are reported at the room temperature. Although there is some intrinsic UV/blue emission from the host lattice, the dominant signals are from the rare-earth sites, with signals characteristic of the REE2+ and REE3+ states. The shapes of the emission bands are different for each dopant. The sharp emission properties show that the SrAl2O 4 is a suitable host for rare-earth ion doped phosphor material. © 2011 Elsevier B.V. All rights reserved.
A theoretical model for uni-directional ant trails
(Elsevier B.V., 2011) Kayacan O.
A theoretical model of uni-directional ant traffic, motivated by the motion of ants in trail is proposed. Two different type of ants, one of which smells very well and the other does not, are considered. The flux of ants in this model is investigated as functions of the probability of evaporation rate of pheromone. The obtained results indicate that the mean velocity of the ants varies non-monotonically with their density. In addition, it is observed that phase transition in the flux and the mean velocity vs. density occurs at certain density for a fixed evaporation rate. The effective hopping probability is investigated as well depending on the evaporation rate of pheromone. It is worth to note that the proposed model can be generalized for vehicular traffic on freeways. © 2010 Elsevier B.V. All rights reserved.
Setting order promising times in a supply chain network using hybrid simulation-analytical approach: An industrial case study
(Elsevier B.V., 2011) Tunali S.; Ozfirat P.M.; Ay G.
Supply chain management (SCM) involves the management of material and information flow among the members of chain such as vendors, manufacturing plants and distribution centers. The main processes in supply chain are production planning, control, distribution and logistics. Effective management of all these processes provides the manufacturing companies great advantages in time based competition. In order to gain a competitive edge, firms must be able to deliver their products fast and on-time. This can be managed by better production planning, scheduling and due-date setting. This paper suggests a hybrid approach for setting realistic order due dates for a produce-to-order manufacturing company operating within a supply chain environment. The proposed hybrid approach combines mathematical and simulation modeling to bring together the advantages of both approaches. © 2011 Elsevier B.V. All rights reserved.
An alternative approach to calculate the density of states in nonextensive statistical mechanics
(Elsevier B.V., 2011) Babacan H.
A relation between the generalized partition function (Tsallis) and density of states is established by using the method of integral transform which enables reducing some integral equations into the algebraic equations. Inverse Mellin transformation of this equation gives the density of states. Similar relation is also hold the for standard partition function (Boltzmann-Gibbs) and the density of states. Using these relations, we recover the density of states for the classical ideal gas within both statistics. © 2010 Elsevier B.V. All rights reserved.
Generalized ICM for image segmentation based on Tsallis statistics
(Elsevier B.V., 2012) Kilic I.; Kayacan O.
In this paper, the iterated conditional modes optimization method of a Markov random field technique for image segmentation is generalized based on Tsallis statistics. It is observed that, for some q entropic index values the new algorithm performs better segmentation than the classical one. The proposed algorithm also does not have a local minimum problem and reaches a global minimum energy point although the number of iterations remains the same as ICM. Based on the findings of the new algorithm, it can be expressed that the new technique can be used for the image segmentation processes in which the objects are Gaussian or nearly Gaussian distributed. © 2012 Elsevier B.V. All rights reserved.
Immobilization of tyrosinase on chitosan-clay composite beads
(Elsevier B.V., 2012) Dinçer A.; Becerik S.; Aydemir T.
Tyrosinase was immobilized on glutaraldehyde crosslinked chitosan-clay composite beads and used for phenol removal. Immobilization yield, loading efficiency and activity of tyrosinase immobilized beads were found as 67%, 25% and 1400U/g beads respectively. Optimum pH of the free and immobilized enzyme was found as pH 7.0. Optimum temperature of the free and immobilized enzyme was determined as 25-30°C and 25°C respectively. The kinetic parameters of free and immobilized tyrosinase were calculated using l-catechol as a substrate and Km value for free and immobilized tyrosinase were found as 0.93mM and 1.7mM respectively. After seven times of repeated tests, each over 150min, the efficiency of phenol removal using same immobilized tyrosinase beads were decreased to 43%. © 2011 Elsevier B.V.
Radioluminescence study of rare earth doped some yttrium based phosphors
(Elsevier B.V., 2012) Ayvacikli M.; Ege A.; Ekdal E.; Popovici E.-J.; Can N.
This paper reports the luminescence emission spectra of Y(Ta,Nb)O 4 activated by rare earth ions such as Eu3+ and Tb 3+. The influence of these rare earth ions on the radioluminescence (RL) of yttrium niobate and tantalate phosphors was investigated. The luminescent properties were studied under X-ray and preliminary RL measurements to further evaluate prepared materials. The emission centers of the rare earth activators (Eu3+, Tb3+) were found to contribute efficiently to the total luminescence. With their various luminescence chromaticities, these rare earth activated phosphors are promising materials for solid-state lighting applications as well as for X-ray intensifying screens in medical diagnosis, providing the broad band variation of visible RL from blue to red. © 2012 Elsevier B.V. All rights reserved.
The Relationship between quality of life and social support in homosexuals living in Izmir, Turkey
(Elsevier B.V., 2012) Altiparmak S.; Temel A.B.; Taner; Altıparmak O.; Yildirim G.
[No abstract available]
Luminescence characterization of cerium doped yttrium gadolinium aluminate phosphors
(Elsevier B.V., 2012) Uysal Satilmis S.; Ege A.; Ayvacikli M.; Khatab A.; Ekdal E.; Popovici E.J.; Henini M.; Can N.
Yttrium gadolinium aluminate ((Y1-xGdx) 3Al5O12:Ce) doped cerium phosphors with the different yttrium and gadolinium concentration were prepared by a wet-chemical route via the reagent simultaneous addition technique (WCS-SimAdd). The phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL), radioluminescence (RL) of cerium doped yttrium gadolinium aluminate phosphors. With increasing Gd dopant concentration, the PL intensity was shifted to the red region. Preliminary RL measurements were performed to further evaluate these newly prepared materials. Intense RL was observed that is typical of Ce3+ doped structure. © 2012 Elsevier B.V. All rights reserved.
Determination of structural and vibrational spectroscopic features of neutral and anion forms of dinicotinic acid by using NMR, infrared and Raman experimental methods combined with DFT and HF
(Elsevier B.V., 2013) Kose E.; Bardak F.; Atac A.; Karabacak M.; Cipiloglu M.A.
In this study; the experimental (NMR, infrared and Raman) and theoretical (HF and DFT) analysis of dini-cotinic acid were presented. 1H and 13C NMR spectra were recorded in DMSO solution and chemical shifts were calculated by using the gauge-invariant atomic orbital (GiAO) method. The vibrational spectra of dinicotinic acid were recorded by FT-Raman and FT-iR spectra in the range of 4000-10 cm1 and 4000-400 cm 1, respectively. To determine the most stable neutral conformer of molecule, the selected torsion angle was changed every 10° and molecular energy profile was calculated from 0° to 360°. The geometrical parameters and energies were obtained for all conformers form from density functional theory (DFT/B3LYP) and HF with 6-311++G(d, p) basis set calculations. However, the results of the most stable neutral and two anion forms (anion1 and anion2 forms) of dinicotinic acid are reported here. The complete assignments were performed on the basis of the total energy distribution (TED) of the vibrational wavenumbers, calculated with scaled quantum mechanics (SQM) method and PQS program. © 2013 Elsevier B.V. All rights reserved.
An experimental and theoretical investigation of Acenaphthene-5-boronic acid: Conformational study, NBO and NLO analysis, molecular structure and FT-IR, FT-Raman, NMR and UV spectra
(Elsevier B.V., 2013) Karabacak M.; Sinha L.; Prasad O.; Asiri A.M.; Cinar M.
The solid state Fourier transform infrared (FT-IR) and FT-Raman spectra of Acenaphthene-5-boronic acid (AN-5-BA), have been recorded in the range 4000-400 cm1 and 4000-10 cm 1, respectively. Density functional theory (DFT), with the B3LYP functional was used for the optimization of the ground state geometry and simulation of the infrared and Raman spectra of the molecule. The vibrational wave numbers and their assignments were examined theoretically using the Gaussian 09 set of quantum chemistry codes and the normal modes were assigned by a scaled quantum mechanical (SQM) force field approach. Hydrogen-bonded dimer of AN-5-BA, optimized by counterpoise correction, has also been studied by B3LYP at the 6-311++G(d,p) level and the effects of molecular association through O-H·O hydrogen bonding have been discussed. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by Gauge-Including Atomic Orbital (GIAO) method. Natural bond orbital (NBO) analysis has been applied to study stability of the molecule arising from charge delocalization. UV spectrum of the title compound was also recorded and the electronic properties, such as frontier orbitals, and band gap energies were measured by TD-DFT approach. The first order hyperpolarizability (β), its components and associated properties such as average polarizability and anisotropy of the polarizability (α and Δα) of AN-5-BA was calculated using the finite-field approach. © 2013 Elsevier B.V. All rights reserved.
Electrochemical deposition and behavior of mixed-valent molybdenum oxide film at glassy carbon and ITO electrodes
(Elsevier B.V., 2013) Koçak S.; Ertaş F.N.; Dursun Z.
The effect of solution composition and the type of the anionic species on the electrochemical formation of mixed-valent molybdenum oxide on a glassy carbon and ITO electrode surfaces was elucidated. Susccessive recording of the voltammograms has shown that anionic species display different stabilizing effect on the reductive formation of hydrogen molybdenum bronzes [MoO 3-x (OH) x ] and chloroacetic acid buffer has given the best results. The deposit was built upon cycling the potential between 0 and -0.9 V (vs. Ag/AgCl) via reduction of Mo(VI) to Mo(V) on the electrode surface in pH 3.0 chloroacetic acid solution. Electrochemical impedance measurements carried out in this medium revealed a shift in potential zero charge values from -0.2 V to -0.55 V after the potential of the GCE had been cycled for 30 min. An establishment of mixed-valent molybdenum oxide deposit by time on the gold electrode surface was proved by quartz crystal microbalance measurements. Atomic force and scanning electron microscopy techniques were made use of so as to characterize the surface structures of the electrodes. X-ray photoelectron spectroscopy studies confirmed that the deposit contains both Mo(V) and Mo(VI). The deposited films exhibited unique catalytic activity towards nitrite oxidation consistent with the change in peak characteristics. © 2012 Elsevier B.V. All rights reserved.

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