Bilateral Trade Elasticities of Turkey

This paper investigates the long-run bilateral trade elasticities of Turkey and its major trading countries. In the long run, Turkish bilateral trade is inelastic (with varying sign). Thus, the devaluation or revaluation of the Turkish Lira should be expected to have only a limited impact on Turkey’s trade balance. On the other hand, Turkish trade is income elastic in the long run but income inelastic in the short run. Nevertheless, the Marshall-Lerner condition is satisfied only for Canada, South Korea and the US. Furthermore, switching to the euro has reduced Turkish imports from the EU members and emerging market crises tend to increase Turkish imports

Revisiting the Twin Deficit Hypothesis for the Economies of Europe

This study presents empirical evidence linking the current account balance to its major determinants such as exchange rate, interest rate and budget balance in 7 of the EU member countries: Bulgaria, Greece, Ireland, Italy, Latvia, Portugal and Spain. Using the panel version of various cointegration tests, we find a long-run relationship between the current account and its determinants. The long-run coefficient of the interest rate is found statistically significant in all estimation techniques. On the other hand, weak evidence is found for the existence of the twin deficit hypothesis

Monetary Approach to Exchange Rate Determination: The Case of Argentina, Brazil, Taiwan and Turkey, 1986-2006

This study evaluates the short-run and long-run performance of the monetary model approach of exchange rate determination for the emerging economies like Argentina, Brazil, Taiwan and Turkey. The study is based on whether there is a cointegration relationship between the nominal exchange rate and the monetary variables such as the money supply, the output, the nominal interest rate and the price differentials. Various estimation techniques are used for testing long-run relationship both for single-country analysis and panel analysis

Determinants of the Current Account in the Eu and PIIGS

This paper investigates the relationship between current account balance and national savings, investment, budget deficit, and real exchange rate. These determinants of the current account are studied empirically by applying the Generalized Method of Moments for a sample of 24 European countries. The sample data are divided into three different groups, PIIGS, EU-PIIGS, and EU in order to study the group-specific estimations. The main result of the paper is that the determinants of our model are capable of accurately explaining past movements in current accounts for all selected groups. Additionally, current account determinants in the economically weak members, PIIGS, behave slightly differently from the rest of the EU

The left sternalis muscle variation detected during mastectomy

The sternalis muscle variation is a well-known anatomical situation. It is present in 8.7% of women and 6.4% of men, although the incidence varies according to sex, race and ethnicity. During a left modified radical mastectomy operation on a 46-year-old female patient a sternalis muscle was detected on the pectoralis major muscle in the superficial fascia. It was in craniocaudal position and was parallel to the body of the sternum. The cylindrical muscle was approximately 8 cm in length and 2 cm in diameter. Such variations are considered to have their origin in embryological development. Awareness of muscular variations and their identification is important both for procedure through the proper dissection planes during breast surgery and in radiological examination and follow-up

The volume fraction of brain ventricles to total brain volume: a computed tomography stereological study

This study has been designed to estimate the volume fraction of the brain ventricles volume to total brain volume and to correlate them with gender and age in normal subjects. Cranial computed tomography (CT) images of 80 normally evaluated subjects (five female and five male for each decade) were selected from 1,073 CT examinations. The volumes of total brain, cerebral aqueduct, fourth, third, and lateral ventricles and their ratios were estimated using the Cavalieri method and volume fraction-stereological methods. The ratio of total brain ventricle volume to total brain volume was comparable between the two genders (p > 0.05, independent t test). Mean volume fraction of total ventricle volume to total brain volume was found to be 1.21% in the first and 3.37% in the last decades. Mean volume fraction was found to increase significantly with age (p < 0.01, r = 0.630, Pearson). In conclusion, the mean percentage of total ventricle volume within the total brain volume was found to be 2%. We demonstrated the volume fraction of total ventricle to total brain in normal subjects. Total ventricle volume to total brain volume fractions can be important tools in determining ventricle volumes, which denote variability in some diseases (Alzheimer, schizophrenia, neurodegenerative disorders, etc.) and can be estimated by stereological methods. (Folia Morphol 2010; 69, 4: 193-200

Investigation of the mixing characteristics of industrial flotation columns using computational fluid dynamics

The mixing characteristics of industrial flotation columns were investigated using computational fluid dynamics (CFD). Particular emphasis was placed on the clarification of the relationship between the liquid and solids mixing parameters such as the mean residence time and axial dispersion coefficients. The effects of particle size and bubble size on liquid dispersion in the column were also studied. An Eulerian-Eulerian method was applied to simulate the multiphase flow, while additional scalar transport equations were introduced to predict the liquid residence time distribution (RTD) and particle age distribution inside the column. The results obtained show that particle residence time decreases with increasing particle size. The residence time of the coarser particles (112.5 ??m) was found to be at least 60% of the liquid residence time, while the finer particles (19 ??m) had a residence time similar to the liquid. The results also show that an increase in the particle size of the solids results in a decrease in the liquid vessel dispersion number, while a decrease in the bubble size increases liquid axial mixing. Finally, the simulated axial velocity profiles confirm the similarity between the liquid and solids axial dispersion coefficients in column flotation

Utility of brain parenchyma density measurement and computed tomography perfusion imaging in predicting brain death

Purpose: To assess the utility of brain parenchyma density measurement on unenhanced computed tomography (CT) in predicting brain death (BD), in order to evaluate the added value of CT perfusion (CTP). Material and methods: A total of 77 patients who were clinically diagnosed as BD and had both CT angiography (CTA) and CTP imaging in the same session were retrospectively reviewed. On unenhanced phase of CTA, density measurement was performed from 23 regions of interests (ROIs) which were located in the following areas: level of basal ganglia (caudate nucleus, putamen, corpus callosum, posterior limb of internal capsule), level of brainstem, greywhite matters on levels of centrum semiovale (CS), high convexity (HC), and cerebellum. CTP images were evaluated qualitatively and independently. Grey matter (GM), white matter (WM), density, and GM/WM density ratio of BD patients were compared with control subjects. Results: Comparing with the normal control group, the GM and WM density at each level and GM/WM density ratio of CS, HC, and cerebellum level were significantly lower in brain-dead patients (p = 0.019 for HC-WM, p < 0.001 for other areas). Using ROC analysis, the highest value of area under curve (AUC) for the GM/WM density ratio was found at the HC level (AUC = 0.907). The sensitivity of the GM/WM density ratio at the HC level was found to be 90% when the cut-off value of 1.25 was identified. Evaluating the GM/WM density ratio together with the CTP results increased the sensitivity further to 98%. Conclusions: The GM/WM density ratio at the HC level on unenhanced CT may be a useful finding to predict BD. Also, the addition of CTP increases the sensitivity of this method

Investigation of flow regime transition in a column flotation cell using CFD

Flotation columns are normally operated at optimal superficial gas velocities to maintain bubbly flow conditions. However, with increasing superficial gas velocity, loss of bubbly flow may occur with adverse effects on column performance. It is therefore important to identify the maximum superficial gas velocity above which loss of bubbly flow occurs. The maximum superficial gas velocity is usually obtained from a gas holdup versus superficial gas velocity plot in which the linear portion of the graph represents bubbly flow while deviation from the linear relationship indicates a change from the bubbly flow to the churn-turbulent regime. However, this method is difficult to use when the transition from bubbly flow to churn-turbulent flow is gradual, as happens in the presence of frothers. We present two alternative methods in which the flow regime in the column is distinguished by means of radial gas holdup profiles and gas holdup versus time graphs obtained from CFD simulations. Bubbly flow was characterized by saddle-shaped profiles with three distinct peaks, or saddle-shaped profiles with two near-wall peaks and a central minimum, or flat profiles with intermediate features between saddle and parabolic gas holdup profiles. The transition regime was gradual and characterized by flat to parabolic gas holdup profiles that become steeper with increasing superficial gas velocity. The churn-turbulent flow was distinguished by steep parabolic radial gas holdup profiles. Gas holdup versus time graphs were also used to define flow regimes with a constant gas holdup indicating bubbly flow, while wide gas holdup variations indicate churn-turbulent flow

Ab-initio vibrational properties of transition metal chalcopyrite alloys determined as high-efficiency intermediate-band photovoltaic materials

In this work, we present frozen phonon and linear response ab-initio research into the vibrational properties of the CuGaS2 chalcopyrite and transition metal substituted (CuGaS2)M alloys. These systems are potential candidates for developing a novel solar-cell material with enhanced optoelectronic properties based in the implementation of the intermediate-band concept. We have previously carried out ab-initio calculations of the electronic properties of these kinds of chalcopyrite metal alloys showing a narrow transition metal band isolated in the semiconductor band gap. The substitutes used in the present work are the 3d metal elements, Titanium and Chromium. For the theoretical calculations we use standard density functional theory at local density and generalized gradient approximation levels. We found that the optical phonon branches of the transition metal chalcopyrite, are very sensitive to the specific bonding geometry and small changes in the transition metal environment