55 research outputs found

    Dissociable Effects of Reward on Attentional Learning: From Passive Associations to Active Monitoring

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    Visual selective attention (VSA) is the cognitive function that regulates ongoing processing of retinal input in order for selected representations to gain privileged access to perceptual awareness and guide behavior, facilitating analysis of currently relevant information while suppressing the less relevant input. Recent findings indicate that the deployment of VSA is shaped according to past outcomes. Targets whose selection has led to rewarding outcomes become relatively easier to select in the future, and distracters that have been ignored with higher gains are more easily discarded. Although outcomes (monetary rewards) were completely predetermined in our prior studies, participants were told that higher rewards would follow more efficient responses. In a new experiment we have eliminated the illusory link between performance and outcomes by informing subjects that rewards were randomly assigned. This trivial yet crucial manipulation led to strikingly different results. Items that were associated more frequently with higher gains became more difficult to ignore, regardless of the role (target or distracter) they played when differential rewards were delivered. Therefore, VSA is shaped by two distinct reward-related learning mechanisms: one requiring active monitoring of performance and outcome, and a second one detecting the sheer association between objects in the environment (whether attended or ignored) and the more-or-less rewarding events that accompany them

    Cerebral blood volume, genotype and chemosensitivity in oligodendroglial tumours

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    INTRODUCTION: The biological factors responsible for differential chemoresponsiveness in oligodendroglial tumours with or without the −1p/−19q genotype are unknown, but tumour vascularity may contribute. We aimed to determine whether dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) could distinguish molecular subtypes of oligodendroglial tumour, and examined the relationship between relative cerebral blood volume (rCBV) and outcome following procarbazine, lomustine and vincristine (PCV) chemotherapy. METHODS: Pretherapy rCBV was calculated and inter- and intraobserver variability assessed. Allelic imbalance in 1p36, 19q13, 17p13, 10p12–15, and 10q22–26 and p53 mutation (exons 5–8) were determined. rCBV was compared with genotype and clinicopathological characteristics (n=37) and outcome following PCV chemotherapy (n=33). RESULTS: 1p/19q loss was seen in 6/9 grade II oligodendrogliomas, 6/14 grade II oligoastrocytomas, 4/4 grade III oligodendrogliomas, and 3/10 grade III oligoastrocytomas. rCBV measurements had good inter- and intraobserver variability, but did not distinguish histology subtype or grade. Tumours with 1p/19q loss had higher rCBV values (Student’s t-test P=0.001). Receiver operating characteristic analysis revealed a cut-off of 1.59 for identifying genotype (sensitivity 92%, specificity 76%). Tumours with high and low rCBV showed response to chemotherapy. The −1p/−19q genotype, but not rCBV, was strongly associated with response, progression-free and overall survival following PCV chemotherapy. Tumours with high rCBV and intact 1p/19q were associated with shorter progression-free and overall patient survival than those with intact 1p/19q and low rCBV or high rCBV and 1p/19q loss. CONCLUSION: rCBV identifies oligodendroglial tumours with 1p/19q loss, but does not predict chemosensitivity. The prognostic significance of rCBV may differ in oligodendroglial tumours with or without the −1p/−19q genotype

    Reconciling the stratigraphy and depositional history of the Lycian orogen-top basins, SW Anatolia

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    Terrestrial fossil records from the SWAnatolian basins are crucial both for regional correlations and palaeoenvironmental reconstructions. By reassessing biostratigraphic constraints and incorporating new fossil data, we calibrated and reconstructed the late Neogene andQuaternary palaeoenvironments within a regional palaeogeographical framework. The culmination of the Taurides inSWAnatolia was followed by a regional crustal extension from the late Tortonian onwards that created a broad array of NE-trending orogen-top basins with synchronic associations of alluvial fan, fluvial and lacustrine deposits. The terrestrial basins are superimposed on the upper Burdigalian marine units with a c. 7 myr of hiatus that corresponds to a shift from regional shortening to extension. The initial infill of these basins is documented by a transition from marginal alluvial fans and axial fluvial systems into central shallow-perennial lakes coinciding with a climatic shift from warm/humid to arid conditions. The basal alluvial fan deposits abound in fossil macro-mammals of an early Turolian (MN11–12; late Tortonian) age. The Pliocene epoch in the region was punctuated by subhumid/humid conditions resulting in a rise of local base levels and expansion of lakes as evidenced by marsh-swamp deposits containing diverse fossilmammal assemblages indicating late Ruscinian (lateMN15; late Zanclean) ageWe are grateful for the support of the international bilateral project between The Scientific and Technological Research Council of Turkey (TUBITAK) and The Russian Scientific Foundation (RFBR) with grant a number of 111Y192. M.C.A. is grateful to the Turkish Academy of Sciences (TUBA) for a GEBIP (Young Scientist Award) grant. T.K. and S.M. are grateful to the Ege University Scientific Research Center for the TTM/002/2016 and TTM/001/2016 projects. M.C.A., H.A., S.M. and M.B. have obtained Martin and Temmick Fellowships at Naturalis Biodiversity Center (Leiden). F.A.D. is supported by a Mehmet Akif Ersoy University Scientific Research Grant. T.A.N. is supported by an Alexander-von-Humboldt Scholarship. L.H.O. received support from TUBITAK under the 2221 program for visiting scientists

    Lung cancer, brucellosis and tuberculosis: Remarkable togetherness

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    A 68 years old male farmer referred with cough, expectorating sputum, intermittant fever, night sweats, fatigue and anorexia persisting for two weeks. There was a history of 80 packs each year of smoking and he was still an active smoker. Pneumonectomy was performed because of pulmonary epidermoid cancer and he received chemotherapy. He was diagnosed lung tuberculosis and using anti-tuberculous treatment for 4 months. He had a weight loss of 8 kg in last month. His body tempereature was 38.5 °C. Heart rate was 100/min. ESR was 51mm/h and CRP was 5.6 mg/dL. There was no proliferation in blood and sputum cultures. Three sputum specimens were examined and AFB wasn't detected. Fibronodular infiltration was seen in right lower zone of chest X-ray. In thorax CT, fibronodular densities were seen in lower lobe anterior and posterior segments. Brucella melitensis was isolated in blood culture. Second bronchoscopy was performed with suspect of brucellosis pneumonia. Brucella tube agglutination test was positive at titer 1/320 in the bronchial lavage fluid and 1/640 in concurrent serum sample. In cases with chronic cough or pneumonia which is irresponsive to nonspecific antibiotherapy, respiratory brucellosis must be rememberred in endemic areas. © 2013 Asian Pacific Tropical Medicine Press

    Chronology of subduction and collision along the İzmir-Ankara suture in Western Anatolia: records from the Central Sakarya Basin

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    Western Anatolia is a complex assemblage of terranes, including the Sakarya Terrane and the Tauride-Anatolide Platform that collided during the late Cretaceous and Palaeogene (80–25 Ma) after the closure of the Izmir-Ankara Ocean. Determining the precise timing at which this ocean closed is particularly important to test kinematic reconstructions and geodynamic models of the Mediterranean region, and the chronology of suturing and its mechanisms remain controversial. Here, we document the Cretaceous-Eocene sedimentary history of the Central Sakarya Basin, along the northern margin of the Neotethys Ocean, via various approaches including biostratigraphy, geochronology, and sedimentology. Two high-resolution sections from the Central Sakarya Basin show that pelagic carbonate sedimentation shifted to rapid siliciclastic deposition in the early Campanian (~ 79.6 Ma), interpreted to be a result of the build-up of the accretionary prism at the southern margin of the Sakarya Terrane. Rapid onset of deltaic progradation and an increase in accumulation rates in the late Danian (~ 61 Ma), as well as a local angular unconformity are attributed to the onset of collision between the Sakarya Terrane and the Tauride-Anatolide Platform. Thus, our results indicate that though deformation of the subduction margin in Western Anatolia started as early as the Campanian, the closure of the İzmir-Ankara Ocean was only achieved by the early Palaeocene. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.National Science Foundation: EAR-1543684 104Y153 Türkiye Bilimsel ve Teknolojik Araştirma KurumuThis work was supported by the Scientific and Technological Research Council of Turkey (TÜBİTAK) under Grant 104Y153; National Science Foundation (NSF) under Grant EAR-1543684

    Akkasdagi area, Turkey

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    The Akkasdagi area, situated in the southern margin of the Tertiary Cankiri- Corum Basin, Central Anatolia, Turkey, includes a 280 m, thick, mostly continental sediment sequence that overlies either marine Palaeogene transgressive deposits or metamorphic rocks of Kirsehir Massif. From bottom to top the sequence can be divided into units of Deliceirmak Fm. (alluvial fan deposits) and Ceritkale member (marine fan-delta and shelf carbonates) of mid-upper Eocene, Guvendik Fm. (gypsum) of Oligocene, and Akkasdagi Fm. (fine to coarse-grained alluvial clastics and lacustrine limestone) of upper Miocene-lower Pliocene. A granitic intrusion was emplaced into the basin after late Eocene. The Neogene succession includes mammalian fossils and the lithological composition of the succession is rather different from its equivalences in other parts of the basin. By facies analysis the Neogene infill could be categorised into alluvial fan deposits (facies association I), fluvial deposits (facies association II), lacustrine deposits (facies association III) and pyroclastic flow deposits (facies association IV). Facies association I is dominant and the others are observed inside as alternating sequences. The facies architecture and facies associations suggest that a structural depression existed in the area and was filled with sediments of distal alluvial fans, flood plains and lakes receiving deposits of distal or terminal alluvial fans and flood plains, and occupied partly by lakes.C1 Ankara Univ, Fac Engn, Dept Geol Engn, Tecton Res Grp, TR-06100 Ankara, Turkey.Gebze Inst Technol, TR-41400 Gebze, Kocaeli, Turkey.Gen Directorate Mineral Res & Explorat, Museum Nat Hist, TR-06520 Ankara, Turkey.Museum Natl Hist Nat, Dept Hist Terre, CNRS, UMR 5143, F-75231 Paris 05, France.Pamukkale Univ, Dept Geol Engn, TR-20100 Denizli, Turkey

    Akkasdagi area, Turkey

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    The Akkasdagi area, situated in the southern margin of the Tertiary Cankiri- Corum Basin, Central Anatolia, Turkey, includes a 280 m, thick, mostly continental sediment sequence that overlies either marine Palaeogene transgressive deposits or metamorphic rocks of Kirsehir Massif. From bottom to top the sequence can be divided into units of Deliceirmak Fm. (alluvial fan deposits) and Ceritkale member (marine fan-delta and shelf carbonates) of mid-upper Eocene, Guvendik Fm. (gypsum) of Oligocene, and Akkasdagi Fm. (fine to coarse-grained alluvial clastics and lacustrine limestone) of upper Miocene-lower Pliocene. A granitic intrusion was emplaced into the basin after late Eocene. The Neogene succession includes mammalian fossils and the lithological composition of the succession is rather different from its equivalences in other parts of the basin. By facies analysis the Neogene infill could be categorised into alluvial fan deposits (facies association I), fluvial deposits (facies association II), lacustrine deposits (facies association III) and pyroclastic flow deposits (facies association IV). Facies association I is dominant and the others are observed inside as alternating sequences. The facies architecture and facies associations suggest that a structural depression existed in the area and was filled with sediments of distal alluvial fans, flood plains and lakes receiving deposits of distal or terminal alluvial fans and flood plains, and occupied partly by lakes

    Stratigraphy and sedimentology of Neogene mammal bearing deposits in the Akkaşdaǧι area, Turkey

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    The Akkaşdaǧι area, situated in the southern margin of the Tertiary Çankιrι-Çorum Basin, Central Anatolia, Turkey, includes a 280 m thick, mostly continental sediment sequence that overlies either marine Palaeogene transgressive deposits or metamorphic rocks of Kirşehir Massif. From bottom to top the sequence can be divided into units of Deliceirmak Fm. (alluvial fan deposits) and Ceritkale member (marine fan-delta and shelf carbonates) of mid-upper Eocene, Güvendik Fm. (gypsum) of Oligocene, and Akkaşdaǧι Fm. (fine to coarse-grained alluvial clastics and lacustrine limestone) of upper Miocene-lower Pliocene. A granitic intrusion was emplaced into the basin after late Eocene. The Neogene succession includes mammalian fossils and the lithological composition of the succession is rather different from its equivalences in other parts of the basin. By facies analysis die Neogene infill could be categorised into alluvial fan deposits (facies association I), fluvial deposits (facies association II), lacustrine deposits (facies association III) and pyroclastic flow deposits (facies association IV). Facies association I is dominant and the others are observed inside as alternating sequences. The facies architecture and facies associations suggest that a structural depression existed in the area and was filled with sediments of distal alluvial fans, flood plains and lakes receiving deposits of distal or terminal alluvial fans and flood plains, and occupied partly by lakes. © Publications Scientifiques du Muséum national d'Histoire naturelle, Paris

    Multiple intracranial abscesses due to Cryptococcus neoformans: an unusual clinical feature in an immunocompetent patient and a short review of reported cases

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    We present a case of multiple intracranial abscesses caused by Cryptococcus neoformans in a patient who presented with no symptoms of immunodeficiency
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