489 research outputs found

    Non-linear Realisation of the N=2, D=6 Supergravity

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    We have applied the method of dualisation to construct the coset realisation of the bosonic sector of the N=2, D=6 supergravity which is coupled to a tensor multiplet. The bosonic field equations are regained through the Cartan-Maurer equation which the Cartan form satisfies. The first-order formulation of the theory is also obtained as a twisted self-duality condition within the non-linear coset construction.Comment: 11 page

    Algebraic Integration of Sigma Model Field Equations

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    We prove that the dualization algebra of the symmetric space coset sigma model is a Lie algebra and we show that it generates an appropriate adjoint representation which enables the local integration of the field equations yielding the first-order ones.Comment: 27p

    On the Symmetric Space Sigma-Model Kinematics

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    The solvable Lie algebra parametrization of the symmetric spaces is discussed. Based on the solvable Lie algebra gauge two equivalent formulations of the symmetric space sigma model are studied. Their correspondence is established by inspecting the normalization conditions and deriving the field transformation laws.Comment: 17 page

    Constraints on North Anatolian Fault Zone Width in the Crust and Upper Mantle From S Wave Teleseismic Tomography

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    We present high-resolution S wave teleseismic tomography images of the western segment of the North Anatolian Fault Zone (NAFZ) in Turkey using teleseismic data recorded during the deployment period of the Dense Array for Northern Anatolia array. The array comprised 66 stations with a nominal station spacing of 7 km, thus permitting a horizontal and vertical resolution of approximately 15 km. We use the current S wave results with previously published P wave teleseismic tomography to produce maps of relative VP/VSanomalies, which we use to highlight the difference in overall composition of the three terranes separated by the northern (NNAF) and southern branches of the NAFZ. Our results show a narrow S wave low-velocity anomaly beneath the northern branch of the NAFZ extending from the upper crust, where it has a width of ∼10 km, to the lower crust, where it widens to ∼30 km. This low-velocity zone most likely extends into the upper mantle, where we constrain its width to be ≤ 50 km and interpret it as indicative of localized shear beneath the NNAF; this structure is similar to what has been observed for the NAFZ west of 32°, and therefore, we propose that the structure of the NNAF is similar to that of the NAFZ in the east. The southern branch of the NAFZ does not show a very strong signature in our images, and we conclude that it is most likely rooted in the crust, possibly accommodating deformation related to rotation of the Armutlu/Almacik Blocks situated between the two NAFZ branches

    Examination of inclinations of the spine at childhood and adolescence

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    Background: Spine is a column that consists of consecutively lined up vertebras. It includes medulla spinalis. It contributes the motions of head, neck and body. Spine is not a straight column. There is a convexity towards the front of the spine (lordosis) at cervical and lumbar areas in adults and a convexity towards the back of the spine (kyphosis) at thoracic and sacral spine areas.  Materials and methods: In this study, lateral magnetic resonance images of 731 children between 1 and 16 years of age were examined and their cervical lordosis, thoracic kyphosis and lumbar lordosis angles were measured with Cobb method using ImageJ programme for every age group.  Results: The mean calculated cervical lordosis angles in 1–16-year-old children were found to be 20.51o ± 6.11o (minimum 17.96o ± 6.29o, maximum 23.50o ± ± 4.14o). It has been observed that cervical angle values decrease with age. The mean thoracic kyphosis angle measured was 28.71o ± 6.99o (minimum 24.55o ± ± 5.65o, maximum 30.44o ± 4.68o). Lumbar lordosis angle was 28.08o ± 7.39o (minimum 20.36o ± 6.59o, maximum 32.68o ± 6.03o). Thoracic kyphosis and lumbar lordosis angle values increased with age. In our study, a statistical differ- ence was found in increasing thoracic kyphosis angle between 1-year-old group and 14-year-old group. Statistical difference was also found in decreasing cervical lordosis angle value between 1-year-old group and 16-year-old group. When we compare our study results with literature values, cervical lordosis values were similar, but lumbar lordosis values were lower.  Conclusions: In summary, we think that knowing sagittal plane inclinations of the spine developing in childhood and adolescence will contribute to earlier de- termination of pathologies. We also hope that it will contribute to clinical stages and other studies in this field.

    Palaeozoic-Recent geological development and uplift of the Amanos Mountains (S Turkey) in the critically located northwesternmost corner of the Arabian continent

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    <p>We have carried out a several-year-long study of the Amanos Mountains, on the basis of which we present new sedimentary and structural evidence, which we combine with existing data, to produce the first comprehensive synthesis in the regional geological setting. The ca. N-S-trending Amanos Mountains are located at the northwesternmost edge of the Arabian plate, near the intersection of the African and Eurasian plates. Mixed siliciclastic-carbonate sediments accumulated on the north-Gondwana margin during the Palaeozoic. Triassic rift-related sedimentation was followed by platform carbonate deposition during Jurassic-Cretaceous. Late Cretaceous was characterised by platform collapse and southward emplacement of melanges and a supra-subduction zone ophiolite. Latest Cretaceous transgressive shallow-water carbonates gave way to deeper-water deposits during Palaeocene-Eocene. Eocene southward compression, reflecting initial collision, resulted in open folding, reverse faulting and duplexing. Fluvial, lagoonal and shallow-marine carbonates accumulated during Late Oligocene(?)-Early Miocene, associated with basaltic magmatism. Intensifying collision during Mid-Miocene initiated a foreland basin that then infilled with deep-water siliciclastic gravity flows. Late Miocene-Early Pliocene compression created mountain-sized folds and thrusts, verging E in the north but SE in the south. The resulting surface uplift triggered deposition of huge alluvial outwash fans in the west. Smaller alluvial fans formed along both mountain flanks during the Pleistocene after major surface uplift ended. Pliocene-Pleistocene alluvium was tilted towards the mountain front in the west. Strike-slip/transtension along the East Anatolian Transform Fault and localised sub-horizontal Quaternary basaltic volcanism in the region reflect regional transtension during Late Pliocene-Pleistocene (<4 Ma).</p

    The Mediterranean Island Wetlands (MedIsWet) inventory: strengths and shortfalls of the currently available floristic data

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    MedIsWet (Conservation of the island wetlands of the Mediterranean Basin) is a MAVA funded project which aims at investigating all seasonal or permanent island wetlands both natural and artificial, with a minimum extent of 0.1 hectares. More than 16,000 wetlands from almost all the Mediterranean, including islands from France, Italy, Malta, Croatia, Cyprus, Tunisia, Turkey, Greece and Spain were mapped. Over 2,500 of them were inventoried in the field and more than 500 scientific contributions catalogued. In total, more than 35,000 plant occurrences were uploaded, in a standardised and comparable way, on the national open-source web portals. These can be related to the recorded threats, uses and other spatially retrievable information. Here, we show strengths and shortfalls of the already available information about the floristic records. Although further improvements are needed, we discuss how these data can be used for research and policy actions and to develop conservation projects

    Patterns of active and passive smoking, and associated factors, in the South-east Anatolian Project (SEAP) region in Turkey

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    BACKGROUND: Smoking is an important health threat in Turkey. This study aimed to determine the frequency of and main factors associated with smoking in persons of 15 years and over, and the frequency of passive smoking in homes in the South-east Anatolian Project (SEAP) Region in Turkey. METHODS: A cross sectional design was employed. The sample waschosen by the State Institute of Statistics using a stratified cluster probability sampling method. 1126 houses representing the SEAP Region were visited. Questionnaires about tobacco smoking and related factors were applied to 2166 women and 1906 men (of 15 years old and above) in their homes. Face-to-face interview methods were employed. Participants were classified as current, ex, and non-smokers. The presence of a regular daily smoker in a house was used as an indication of passive smoking. The chi-square andlogistic regressionanalysis methods were used for the statistical analysis. RESULTS: The prevalence of smoking, in those of 15 years and over, was 11.8% in women and 49.7% in men. The prevalence of current smokers was higher in urban (34.5 %) than in rural (22.8 %) regions. The mean of total cigarette consumption was 6.5 packs/year in women and 17.9 packs/year in men. There was at least one current smoker in 70.1% of the houses. CONCLUSION: Smoking is a serious problem in the South-eastern Anatolian Region. Male gender, middle age, a high level of education and urban residency were most strongly associated with smoking
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