Analysis of Age as a Possible Prognostic Factor for Transcanalicular Multidiode Laser Dacryocystorhinostomy

Purpose. To assess the prognostic value of age on the outcome of transcanalicular multidiode laser dacryocystorhinostomy (TCL-DCR) in patients with acquired nasolacrimal duct obstruction (NLDO). Methods. The medical records of TCL-DCR performed between March 2009 and September 2013 were reviewed retrospectively. Inclusion criteria include over 20 years of age, similar mean follow-up period, and similar mean duration of stenting. The main outcome is surgical success. The effect of age on success rate is also evaluated. Results. The anatomical success was 52% in Group 1 (20–30 years), 56% in Group 2 (31–40 years), 64% in Group 3 (41–50 years), 76% in Group 4 (51–60 years), and 88% in Group 5 (over 60 years). The statistical difference among Group 1 and Group 5, in terms of surgical success rate, was found to be significant (P=0.009). Additionally, the 20–30-year-old patients had a failure rate 6.76 times higher than that of the over-60-year-old patients (P=0.009; 95% CI, 1.605–28.542). Conclusion. TCL-DCR is a surgical treatment option for NLDO for which a skin incision can be avoided. The success rate of TCL-DCR for younger population is lower when compared with elderly population

Implications of 2007's Earthquake Activity in Egirdir Lake (SW Anatolia) Based on Moment Tensor Solutions and Inversion of Stress State

We analyzed the waveforms of the small- to moderate-sized earthquakes that took place in the northern part of the inner Isparta Angle (IA) to retrieve their source parameters and combine these results with the focal mechanism solutions of the larger events that occurred in 2007 in Egirdir Lake at the apex of IA. In total, source mechanisms of 20 earthquakes within the magnitude range 3.5 < M < 5.0 were calculated using a regional moment tensor inversion technique. The inversion of the focal mechanisms yields an extensional regime with a NNE-SSW (N38A degrees E) trending sigma (3) axis. Inversion results are related to a mainly WNW-ESE oriented normal fault beneath Egirdir Lake. The R value of a NNE-SSW extensional regime is 0.562 showing a triaxial stress state in the region. The current stress regime results from complex subduction processes such as slab pull, slab break-off, roll-back and/or retreating mechanism along the Hellenic and Cyprus arcs and the southwestward extrusion of the Anatolian block since the early Pliocene

Solar and lunar geomagnetic variations in the northwestern part of Turkey

Hourly mean values of X, Y and Z components of the geomagnetic field from two observatories and the total intensity, F, of the geomagnetic field from eight monitoring stations were analysed to study the behaviour of solar and lunar geomagnetic variations in the northwestern part of Turkey. The ChapmanMiller method was applied to the data first as a whole and then by grouping it to Lloyd's seasons to calculate seasonal dependence of the harmonics. Amplitudes of solar and lunar harmonics increase from winter months to summer months. The first two harmonics of both solar and lunar origins were calculated annually to compare with sunspot relative numbers to see annual and semi-annual variation. The solar harmonics show very good sunspot dependence, but lunar harmonics do not. It means that both ionospheric and ring current systems have an important role in the formation of solar harmonics, but lunar harmonics are affected by ionospheric current system only in the northwestern part of Turkey. We would not expect and we do not find much ocean effect at these observatories since they are all remote from oceans with significant tides

Upper crustal electrical resistivity structures in the vicinity of the Catalca Fault, Istanbul, Turkey by magnetotelluric data

A magnetotelluric survey was performed at the Catalca Region, west of Istanbul, Turkey with the aim of investigating geoelectrical properties of the upper crust near the Catalca Fault and its vicinity. Broadband magnetotelluric data were collected at nine sites along a single southwest-northeast profile to image the electrical resistivity structure from surface to the 5 km depth. The dimensionality of the data was examined through tensor decompositions and highly two-dimensional behavior of the data is shown. Following the tensor decompositions, two-dimensional inversions were carried out where E-polarization, B-polarization and tipper data were utilized to construct electrical resistivity models. The results of the inversions suggest: a) the Catalca Fault extends from surface to 5 km depth as a conductive zone dipping to southwest; b) the thickness of the sedimentary cover is increasing from SW to NE to 700 m with low resistivity values between 1-100 Omega m; c) the crystalline basement below the sedimentary unit is very resistive and varies between 2000-100000 Omega m; d) a SW-dipping resistivity boundary in the northeastern part of our profile may represent the West Black Sea Fault

Electrical characterization of the North Anatolian Fault Zone underneath the Marmara Sea, Turkey by ocean bottom magnetotellurics

The first magnetotelluric study in the Marmara Sea, Turkey, was undertaken to resolve the structure of the crust and upper mantle in the region, and to determine the location of the westward extension of the North Anatolian Fault (NAF) in the Cinarcik area. Long-period ocean bottom magnetotelluric data were acquired at six sites along two profiles crossing the Cinarcik Basin, where a significant increase in microseismic activity was observed following the devastating 1999 Izmit and Duzce earthquakes. 2-D resistivity models indicate the existence of a conductor at a depth of similar to 10 km in the middle of both profiles along with a deeper extension into the upper mantle, implying the presence of fluid in the crust and partial melting in the upper mantle. The northern and southern boundaries of this conductor are interpreted to represent the northern and southern branches of the NAF in the Marmara Sea, respectively. These conductors have been previously identified farther to the east along the NAF, suggesting that the electrical characteristics of this fault are continuous from onland areas into the Marmara Sea. Microseismic activity in the Cinarcik area is located above the conductor documented here, and indicates a possible seismogenic role of crustal fluids present in the conductive zone. In comparison, resistive zones along the NAF may act as asperities that could eventually result in a large earthquake

Rapid changes in the electrical state of the 1999 Izmit earthquake rupture zone

Crustal fluids exist near fault zones, but their relation to the processes that generate earthquakes, including slow-slip events, is unclear. Fault-zone fluids are characterized by low electrical resistivity. Here we investigate the time-dependent crustal resistivity in the rupture area of the 1999 M-w 7.6 Izmit earthquake using electromagnetic data acquired at four sites before and after the earthquake. Most estimates of apparent resistivity in the frequency range of 0.05 to 2.0 Hz show abrupt co-seismic decreases on the order of tens of per cent. Data acquired at two sites 1 month after the Izmit earthquake indicate that the resistivity had already returned to pre-seismic levels. We interpret such changes as the pressure-induced transition between isolated and interconnected fluids. Some data show pre-seismic changes and this suggests that the transition is associated with foreshocks and slow-slip events before large earthquakes

Molecular epidemiology of HIV-1 strains in the south-east and east of Turkey

Objective: To detect the subtype characterization and drug-resistant mutations in HIV-1 strains after the refugee movement from Syria to Turkey between 2011 and 2014 in south east border lines. Methods: A total of 65 patients were included in this study, of which 57 (88%) patients were antiretroviral therapy-naive patients. HIV-1 RNA was detected and quantified by real-time PCR assay. HIV-1 subtypes and circulating recombinant forms (CRFs) were identified by phylogenetic analysis (neighbor-joining method), and drug-resistant mutations were analyzed. Results: Three major HIV groups were indicated. Two of these groups were located in subtype B. The other group showed heterogeneity. Subtype B (48/65, 73.8%), followed by CRFs (12/65, 18.5%) was the most common strain. Subtype of CRFs consisted of CRF01_AE (9/65, 13.8%) and CRF02_AG (3/65, 4.6%). Subtype C (1/65, 1.5%), sub-subtypes A1 (2/65, 3.1%) and F1 (2/65, 3.1%) were also detected with low prevalence. The rate of overall primary antiretroviral resistance was 4.9% (3/61). Drug-resistant rate for non-nucleoside reverse transcriptase inhibitors was 4.9%. The thymidine analogue mutation rate was 13.1% (8/61). Conclusions: HIV molecular epidemiology studies are necessary to determine transmission patterns and spread. Subtype B and CRF01_AE, CRF02_AG are the most prevalent strains in the south-east of Turkey. However, subtype C, sub-subtypes A1 and F1 are of low prevalence but persist in the south-east of Turkey. In the near future, changing of HIV epidemiology will be possible in Turkey due to migration movement in border lines and resistance testing will play an important role in HIV management