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The co-seismic properties of the Mw 6.0 (12:07:03 UTC) and Mw 6.4 (12:08:06 UTC) doublet earthquakes that took place on 14 November 2021, N-Bandar Abbas Syntaxis (Fin region), SE-Zagros Simply Folded Belt (SFB), Iran, are thoroughly examined. Understanding the earthquake ruptures and their relationship to the co-seismic deformations, critical to our knowledge about the earthquake source mechanisms, has provided a singular chance to interpret the details of the rupture procedure of these two interrelated earthquakes, to complement previous studies of seismicity. Here, using finite-fault source inversion, we first estimated the co-seismic source models and then the co-seismic displacements during the earthquakes, differentiated into vertical/horizontal components. We inverted the observed tele-seismic broadband P velocity waveforms of the earthquakes to simultaneously estimate the finite-fault rupture process, the slip distribution, the fault geometry and the stress changes. We found that the earthquakes were typical blind thrust-fault types along NW–SE and NE–SW striking fault lengths of ~ 40–50 km, widths of ~ 25–30 km, at a depth range of ~ 3–16 km and ~ 3–15 km, respectively, with co-seismic surface folding (~ 7–10 km) to NE controlled by a salt décollement layer at a depth range of ~ 10–12 km. We also found that the earthquakes consisted of relatively fast rupture sources (VR 3.3 km/s); an initial pure thrust faulting bilateral rupture at a depth of 12 km with a maximum slip of 30 cm and a dip angle of 32°, which was followed by a bilateral rupture with an oblique-slip left-lateral thrust faulting at a depth of 10 km, with a maximum slip of 80 cm and a dip angle of 24° propagated towards the NE. The joint interpretation of estimated Coulomb stress changes imparted by proposed variable slip rupture models, and the salt layer indicated that the stress increased load, triggered the fault planes of both events and influenced along-strike co-seismic strain distribution, providing evidence for the SW–NE trending activation of the stress decoupling between the ruptures, corresponding to the salt décollement. The initial pure thrust motion ruptured and mobilised the salt layer, then triggered and activated the bilateral rupture that generated the co-seismic detachment folds subparallel to the décollement. The weak salt, co-seismically ruptured and rapidly activated, compensated co-seismic strain through lateral thickness changes from SW to NE and obliquely accommodated the folding in the shallow cover. Thus, basal ductile shear facilitated the change from pure thrust faulting in the basement to oblique thrust faulting in the cover. This finding clarifies differences in rupturing properties and deformation styles of such low-angle thrust faults. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the 36 months changes in posterior corneal surface parameters in keratoconic eyes after accelerated corneal cross-linking and to compare the data with uncross-linked progressive and non-progressive keratoconic eyes. Methods: Thirty five cross-linked, 30 uncross-linked progressive, and 30 uncross-linked non-progressive keratoconic eyes were included. Maximum keratometry (Kmax), thinnest pachymetry, minimum radius of curvature back (Rminback), asphericity back, posterior elevation and corneal densitometry, back corneal higher order aberrations (HOAs), back surface deviation (Db), final D, posterior radius of curvature (PRC) and 'B' unit values were recorded at baseline and at the 12, 24, 36 months follow-up. Data were analyzed with repeated measures ANOVA and paired t-tests. Results: Kmax and thinnest pachymetry were significantly changed in the cross-linked and progressive uncross-linked groups. Rminback, asphericity back, and HOAs did not change in either group. Total posterior corneal densitometry improved; posterior elevation, Db and B unit worsened in the cross-linked group and did not change in the uncross-linked groups. PRC and final D worsened in the cross-linked and progressive uncross-linked groups, and did not change in the non-progressive group. Conclusion: Despite a decreased Kmax, the posterior corneal surface parameters, posterior elevation values were determined to have significantly worsened in the cross-linked group and this increase was higher than in progressive uncross-linked eyes. [ABSTRACT FROM AUTHOR]

On 30 October 2020, an Mw 6.9 normal faulting earthquake to the north and offshore from the island of Samos, very close to the south west coast of Turkey, occurred at 14:51 local time (11:51:34.8 UTC). In this study, the stress change features of the rupture process and the co-seismic surface deformation of the island of Samos during this event are analyzed. The co-seismic slip distribution model of the causative fault was initially adopted, inverted from the Global Centroid Moment Tensor (GCMT) solution for the Mw 6.9 Samos 2020 earthquake. Then, this GCMT-inverted fault source model (uniform-slip) was used to compute the co-seismic Coulomb stress changes in the crustal volume affected by the early seismicity and to analyze the Coulomb stress change characteristics of the mainshock in terms of early aftershocks, stress state of the causative fault, and of the adjacent Samos island. Lastly, interferometric synthetic aperture radar (InSAR) interferograms (Sentinel-1 satellites) were used to measure the co-seismic surface displacements of the adjacent island of Samos and to evaluate stress transfer of the causative fault. Finally, the results obtained from the Coulomb stress changes associated with the co-seismic slip distribution and InSAR observations were compared. The Coulomb stress change features caused by the uniform-slip for the causative fault were in good agreement with the pattern of aftershock distributions in the first week following the mainshock. It was found that most of the aftershocks occurred in end-fault and off-fault lobes, as areas of Coulomb stress increase of 2–5 bar, and in the stress shadow zone near the rupture, as an area of Coulomb stress decreases of between − 4 and − 5 bar, corresponding to the largest slip patch (~ 2.7 m) according to the uniform-slip. A rupture propagation direction from E (~ 2.7 m max. slip) to W (~ 30 cm min. slip) and asymmetric deepening of the slip distribution down to a depth > 10 km in the fault plane, in agreement with our uniform-slip model, explained the Samos mainshock, Coulomb stress changes, and co-seismic deformation of Samos island. The best constraints on the early deformation pattern of Samos island, in the absence of near-mainshock seismic stations, obtained from InSAR data revealed maximum displacement (± ~ 10 cm) of the island from E to W and from SE (subsidence) to NW (uplift). Finally, based on the Coulomb stress change and InSAR computation, it is concluded that the 2020 Samos mainshock increased the stress level of the assumed faults and/or possible fault segments in the N and adjacent to Samos island in the S as a result of end-fault and off-fault lobes. [ABSTRACT FROM AUTHOR]

This study presents an analysis of the single-channel high-resolution shallow seismic reflection data from Lake Erçek, eastern Anatolia, to provide key information on the deformational elements, on the fault patterns and on the overall tectonic structure of the Lake Erçek Basin. High-resolution seismic data reveal major structural and deformational features, including N-S trending normal faults and W-E trending reverse faults bounding the Lake Erçek Basin, basement highs and folded structures along the marginal sections of the lake. The N-S trending normal faults asymmetrically control the steep western margin and the gentle eastern deltaic section, while the W-E trending reverse faults appear at the northern and southern margins. The N-S trending normal faults, half-graben structure, and the gradual thickening of sediments in the Erçek Basin toward the fault scarps strongly suggest an extensional tectonic regime resulting from an N-S compression. The Erçek Basin is an extension-controlled depocenter; it is a relatively undeformed and flat-lying deep Basin, forming a typical example of the half-graben structure. The N-S trending normal faults appear to be currently active and control the lake center and the E-delta section, resulting in subsidence in the lake floor. In the N- and S-margins of the lake, there is evidence of folding, faulting and accompanying block uplifting, suggesting a significant N-S compressional regime that results in the reverse faulting and basement highs along the marginal sections. The folding and faulting caused strong uplift of the basement blocks in the N- and S- margins, subsequently exposing the shelf and slope areas. The exposed areas are evident in the erosional unconformity of the surface of the basement highs and thinned sediments. The tilted basement strata and subsequent erosion over the basement block highs suggest prominent structural inversion, probably long before the formation of the lake. New high-resolution seismic data reveal the fault patterns and structural lineaments of the Lake Erçek and provide strong evidence for an ongoing extension and subsidence. The present study provides new structural insights that will support future tectonic and sedimentary studies and the development of strategies related to active earthquake faults and major seismic events in the region of Lake Erçek. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to compare the effects of widely used multipurpose contact lens solutions against Staphylococcus aureus and Pseudomonas aeruginosa, in addition to cystic and trophozoite forms of Acanthamoeba castellanii and A. polyphaga, that cause microbial keratitis. Methods: Three multipurpose solutions were tested: SOLO-care, ReNu, and Opti-Free Express. The test solutions were challenged with P. aeruginosa (ATCC 27853) and S. aureus (ATCC 2913) based on the ISO stand-alone and regiment test procedure for disinfecting products, A. polyphaga (ATCC 30871) and A. castellanii (1501/1A) cystic and trophozoite forms. Multipurpose solutions were sampled for surviving microorganisms at manufacturer's minimum recommended disinfection time. The number of viable organisms was determined, and log reductions were calculated. Results: ReNu and SOLO-care resulted in a reduction greater than the required mean 3.0 logarithmic reduction against S. aureus, and SOLO-care and Opti-Free Express resulted in a reduction more than the required mean 3.0 logarithmic reduction against P. aeruginosa. Against the cystic and trophozoite forms of A. castellanii, the log reduction provided by SOLO-care was 1.01 and 1.31 log, respectively. ReNu provided a 0.83 log reduction of the cystic form and a 1.21 log reduction of the trophozoite form. Using Opti-Free Express, the log reduction for both forms was 1.31. SOLO-care led to a 0.61 log reduction of the cystic form of A. polyphaga and a 1.01 log reduction of the trophozoite form. ReNu provided a 0.41 log reduction of the cystic form and a 4.99 log reduction of the trophozoite form. Opti-free Express resulted in a 0.89 log reduction of the cystic form and a 3.11 log reduction of the trophozoite form. Conclusions: Multipurpose contact lens solutions using similar regimens can show different disinfection abilities. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the mean platelet volume (MPV) of patients with central serous chorioretinopathy (CSCR). Thirty patients were included in the study. Thirty healthy volunteers were recruited as the control group. All patients and control subjects underwent complete ocular examination. Hemoglobin, hematocrit, white blood cell, neutrophil, lymphocyte, platelet count, and MPV of the participants were recorded. Data of patients with CSCR were compared with the control subjects. Patients with CSCR had significantly higher MPV values (9.76 ± 1.36 fL) compared with the control subjects (8.37 ± 0.72 fL) ( p = 0.004). No significant difference was found in platelet counts between the CSCR group and the control group (259 ± 53.75 and 243 ± 52.11 K/Ul, p = 0.253). According to the receiver operator characteristics curve analysis, the optimal cut-off value of MPV to predict the CSCR was >9.4, with 60.0 % sensitivity and 93.3 % specificity. Our results demonstrated that the MPV values were significantly higher in patients with CSCR. MPV may be used as a predictive tool for identifying risk for CSCR. [ABSTRACT FROM AUTHOR]

The structural evolution of Lake Van Basin, eastern Turkey, was reconstructed based on seismic reflection profiles through the sedimentary fill as well as from newly acquired multibeam echosounder data. The major sub-basins (Tatvan Basin and Northern Basin) of Lake Van, bound by NE-trending faults with normal components, formed during the past ~600 ka probably due to extensional tectonics resulting from lithospheric thinning and mantle upwelling related to the westward escape of Anatolia. Rapid extension and subsidence during early lake formation led to the opening of the two sub-basins. Two major, still active volcanoes (Nemrut and Süphan) grew close to the lake basins approximately synchronously, their explosive deposits making up >20 % of the drilled upper 220 m of the ca. 550-m-thick sedimentary fill. During basin development, extension and subsidence alternated with compressional periods, particularly between ~340 and 290 ka and sometime before ~14 ka, when normal fault movements reversed and gentle anticlines formed as a result of inversion. The ~14 ka event was accompanied by widespread uplift and erosion along the northeastern margin of the lake, and substantial erosion took place on the crests of the folds. A series of closely spaced eruptions of Süphan volcano occurred synchronously suggesting a causal relationship. Compression is still prevalent inside and around Lake Van as evidenced by recent faults offsetting the lake floor and by recent devastating earthquakes along their onshore continuations. New, high-resolution bathymetry data from Lake Van reveal the morphology of the Northern Ridge and provide strong evidence for ongoing transpression on a dextral strike-slip fault as documented by the occurrence of several pop-up structures along the ridge. [ABSTRACT FROM AUTHOR]

Purpose: To investigate levels of ghrelin in the aqueous humour (AqH) of patients with exfoliation syndrome and exfoliation glaucoma and compare them to levels of ghrelin in control subjects. Methods: This cross-sectional study involved 15 patients with exfoliation syndrome, 8 with exfoliation glaucoma and 12 control subjects for whom cataract surgery was indicated. The AqH was aspirated from the anterior chamber with a 27-G needle under sterile conditions prior to tissue manipulation. Ghrelin levels were quantified using radioimmunassay kits. Results: Levels of ghrelin in the AqH were 187.87 ± 80.1 pg/mL in the eyes exhibiting exfoliation syndrome, 98.53 ± 50.9 pg/mL in the eyes exhibiting exfoliation glaucoma and 111.40 ± 77.5 pg/mL in the controls. Ghrelin level of patients with exfoliation syndrome were significantly higher than those of patients with exfoliation glaucoma and the controls ( P < 0.05). Ghrelin levels of patients with exfoliation glaucoma were lower than those of the controls but were not reach statistically significant ( P > 0.05). Age, gender and IOP did not have a significant effect on ghrelin levels in patients with exfoliation syndrome and exfoliation glaucoma. Conclusion: This study is the first to report elevated levels of ghrelin in the AqH in eyes exhibiting exfoliation syndrome. Findings suggest ghrelin might play role in the etiopathogenesis of exfoliation syndrome to exfoliation glaucoma. [ABSTRACT FROM AUTHOR]

This paper presents results of a multi-channel seismic reflection survey at Lake Van and provides constraints on the sedimentary evolution of the lake. The geophysical data of the lake confirm the existence of three physiographic provinces: a shelf, a slope, and a deep, relatively flat basin. The most prominent features identified on the shelf and slope are clinoforms, submerged channels, as well as closely spaced lake floor depressions, reflecting a highly variable lake-level history. The morphological depressions are interpreted as resulting from subaquatic erosion by channelized, sediment-laden currents into horizontally bedded fan sediments. Submerged channels on the eastern shelf are interpreted as meandering-slope channels, probably as a consequence of a lake-level fall that exposed the shelf area. Clinoforms on the Eastern fan may represent relict deltas formed during stationary or slightly rising lake-level intervals. Merging subsurface imaging interpretation with morphological studies of exposed sediments reveals lake-level fluctuations of several hundreds of meters during the past ca. ~550 ka. The lake has three prominent basins (Tatvan, Deveboynu, and the Northern basin) separated by basement ridges (e.g., the Northern ridge). The seismic units in the Tatvan and Northern basins are dominated by alternations of well-stratified and chaotic reflections, while the Deveboynu basin subsurface consists mainly of chaotic units. The chaotic seismic facies are interpreted as mass-flow deposits, probably triggered by earthquakes and/or rapid lake-level fluctuations. The moderate-to-high-amplitude, well-stratified facies seen in the deeper parts of the basins are interpreted as lacustrine deposits intercalated with tephra layers. The occurrence of a clinoform in the deepest part of the lake suggests a major flooding stage of Lake Van more than ~400 ka ago. Seismic profiles from the deepest part of the lake basin show remarkably uniform and continuous stratigraphic units without any major erosional feature following the flooding event, indicating that the lake was never completely dry afterward and therefore significantly older than previously suggested. [ABSTRACT FROM AUTHOR]