Purchasing power parıty with multiple structural breaks: evidence from Turkey

This paper aims to test the validity of the purchasing power parity hypothesis by analyzing the stochastic behavior of Turkey`s real exchange rate for the period 1990–2006. For this purpose, the minimum LM unit root test with two structural breaks is applied to real exchange rate data, which consists of monthly series of CPI-based real exchange rate index. The test results indicate that real exchange rate is trend-stationary. Following Papell and Prodan (2006), the trend-stationary real exchange rate can be interpreted as evidence that supports the validity of the Trend Qualified PPP (TQPPP) for Turkey. This result also suggests that shocks do not have any permanent effect on the real exchange rate in Turkey.Exchange rate

IS REAL EXCHANGE RATE STATIONARY FOR TURKEY? EVIDENCE FROM THE TWO-BREAK LM UNIT ROOT TEST

This paper aims to analyze the stochastic behavior of Turkey's real exchange rate for the period 1990-2006. For this purpose, the minimum LM unit root test with two structural breaks is applied to real exchange rate data, which consists of monthly series of CPI-based real exchange rate index. The test results indicate that real exchange rate is stationary, supporting the validity of the purchasing power parity (PPP) hypothesis in the long run. This result also suggests that shocks do not have any permanent effect on the real exchange rate in Turkey.

XPS characterization of Bi and Mn collected on atom-trapping silica for AAS

The chemical state of analyte species collected on a water-cooled silica tube during atom-trapping atomic absorption spectrometric determination is investigated with the use of X-ray photoelectron spectroscopy (XPS) for Bi and Mn. Analysis of the Bi 4f(7/2) peak reveals that the chemical state of Bi is +3 during initial trapping (before the atomization stage), but an additional 0-valence state of Bi is also observed after the atomization stage. With the use of the measured Mn 2p(3/2) binding energy together with the observed 3s multiplet splitting, the chemical state of Mn is determined as +2 in all stages. Together with our previous determination of 0 valence for Au, it is now postulated that the stability of certain valence states of the three elements (Au, Bi, and Mn) on the silica matrix can be correlated to their electrochemical reduction potentials

Refractive Index Enhancement with Vanishing Absorption in an Atomic Vapor

We report a proof-of-principle experiment where the refractive index of an atomic vapor is enhanced while maintaining vanishing absorption of the beam. The key idea is to drive alkali atoms in a vapor with appropriate control lasers and induce a gain resonance and an absorption resonance for a probe beam in a two-photon Raman configuration. The strength and the position of these two resonances can be manipulated by changing the parameters of the control lasers. By using the interference between these two resonances, we obtain an enhanced refractive index without an increase in the absorption.Comment: 11 pages, 4 figure

Fast Ground State Manipulation of Neutral Atoms in Microscopic Optical Traps

We demonstrate Rabi flopping at MHz rates between ground hyperfine states of neutral $^{87}$Rb atoms that are trapped in two micron sized optical traps. Using tightly focused laser beams we demonstrate high fidelity, site specific Rabi rotations with crosstalk on neighboring sites separated by $8 \mu\rm m$ at the level of $10^{-3}$. Ramsey spectroscopy is used to measure a dephasing time of $870 \mu\rm s$ which is $\approx$ 5000 times longer than the time for a $\pi/2$ pulse.Comment: 4 pages, 4 figure

The variations and degenerative changes of sacroiliac joints in asymptomatic adults

Background: The sacroiliac joint has a structure in which the direction of the load relative to the articular surface is irrational, as the joint surface is not perpendicular to the trunk load axis; it is likely to incur more degenerative changes than other weight-bearing joints. Materials and methods: This retrospective study consisted of a total of 145 cases — 104 (71.7%) men and 41 (28.3%) women — who were referred to Gaziantep University Medical Faculty Radiology Department Polyclinic for pelvic computed tomography (CT) from 2013 to 2018. The mean age was 33.5 years (range: 18–60 years). Pelvis CT images were performed according to the exclusion criteria specified by the experienced orthopaedic surgeon. Patients were excluded from the study if they were younger than the age of 18, had a condition involving the sacroiliac joint, had an endocrine disorder, or had a history of a trauma affecting the pelvis CT examination. Results: In this current study, six types of anatomic variations were detected. Iliosacral complex variation has been determined as the most common type of variation. The incidence of variations of sacroiliac joint in all cases was 28.9%. Degenerative changes were seen in 5.5% of patients fewer than 30 years of age. When it comes to the patients whose age range is 30–60, the percentage of the degenerative changes is 12.4%. In patients who were 30 years and older, the prevalence of degenerative changes increased progressively with increasing age. Conclusions: In this study, it is thought that the knowledge of variations in normal population and degenerative changes will contribute to the better understanding of normal morphological structure of sacroiliac joint and to the anatomical literature. It’s seen that there is not a statistically significant relationship between degenerative changes and anatomical variations

Structural dynamics and transient lipid binding of synaptobrevin-2 tune SNARE assembly and membrane fusion.

Intrinsically disordered proteins (IDPs) and their conformational transitions play an important role in neurotransmitter release at the neuronal synapse. Here, the SNARE proteins are essential by forming the SNARE complex that drives vesicular membrane fusion. While it is widely accepted that the SNARE proteins are intrinsically disordered in their monomeric prefusion form, important mechanistic aspects of this prefusion conformation and its lipid interactions, before forming the SNARE complex, are not fully understood at the molecular level and remain controversial. Here, by a combination of NMR and fluorescence spectroscopy methods, we find that vesicular synaptobrevin-2 (syb-2) in its monomeric prefusion conformation shows high flexibility, characteristic for an IDP, but also a high dynamic range and increasing rigidity from the N to C terminus. The gradual increase in rigidity correlates with an increase in lipid binding affinity from the N to C terminus. It could also explain the increased rate for C-terminal SNARE zippering, known to be faster than N-terminal SNARE zippering. Also, the syb-2 SNARE motif and, in particular, the linker domain show transient and weak membrane binding, characterized by a high off-rate and low (millimolar) affinity. The transient membrane binding of syb-2 may compensate for the repulsive forces between the two membranes and/or the SNARE motifs and the membranes, helping to destabilize the hydrophilic-hydrophobic boundary in the bilayer. Therefore, we propose that optimum flexibility and membrane binding of syb-2 regulate SNARE assembly and minimize repulsive forces during membrane fusion

Introducción. El Placer en la Edad Media: artículos presentados en el 2013 International Medieval Congress, Leeds.

No disponible en català. Vegeu resum en anglèsThe papers in this edition of Mirabilia are derived from presentations at the 2013 Leeds International Medieval Congress (IMC). As a large gathering of scholars, the largest of its kind in Europe, with numerous sessions for short presentations, the IMC has proved an ideal forum for early career scholars. Many a young scholar, from both hemispheres and from every continent, has presented her or his first international paper at Leeds. But it is not only a forum for young scholars. Established academics come every year, presenting new ideas alongside their peers: as can be seen in the following collection