403 research outputs found

    Forecasting The Exchange Rate Series With Ann: The Case Of Turkey

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    As it is possible to model both linear and nonlinear structures in time series by using Artificial Neural Network (ANN), it is suitable to apply this method to the chaotic series having nonlinear component. Therefore, in this study, we propose to employ ANN method for high volatility Turkish TL/US dollar exchange rate series and the results show that ANN method has the best forecasting accuracy with respect to time series models, such as seasonal ARIMA and ARCH models. The suggestions about the details of the usage of ANN method are also made for the exchange rate of Turkey.Activation function, ARIMA, ARCH, Artificial neural network, Chaotic series, Exchange rate, Forecasting, Time series

    The Association Between Familial Risk and Brain Abnormalities Is Disease Specific: An ENIGMA-Relatives Study of Schizophrenia and Bipolar Disorder

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    Background: Schizophrenia and bipolar disorder share genetic liability, and some structural brain abnormalities are common to both conditions. First-degree relatives of patients with schizophrenia (FDRs-SZ) show similar brain abnormalities to patients, albeit with smaller effect sizes. Imaging findings in first-degree relatives of patients with bipolar disorder (FDRs-BD) have been inconsistent in the past, but recent studies report regionally greater volumes compared with control subjects. Methods: We performed a meta-analysis of global and subcortical brain measures of 6008 individuals (1228 FDRs-SZ, 852 FDRs-BD, 2246 control subjects, 1016 patients with schizophrenia, 666 patients with bipolar disorder) from 34 schizophrenia and/or bipolar disorder family cohorts with standardized methods. Analyses were repeated with a correction for intracranial volume (ICV) and for the presence of any psychopathology in the relatives and control subjects. Results: FDRs-BD had significantly larger ICV (d = +0.16, q <.05 corrected), whereas FDRs-SZ showed smaller thalamic volumes than control subjects (d = Ôłĺ0.12, q <.05 corrected). ICV explained the enlargements in the brain measures in FDRs-BD. In FDRs-SZ, after correction for ICV, total brain, cortical gray matter, cerebral white matter, cerebellar gray and white matter, and thalamus volumes were significantly smaller; the cortex was thinner (d < Ôłĺ0.09, q <.05 corrected); and third ventricle was larger (d = +0.15, q <.05 corrected). The findings were not explained by psychopathology in the relatives or control subjects. Conclusions: Despite shared genetic liability, FDRs-SZ and FDRs-BD show a differential pattern of structural brain abnormalities, specifically a divergent effect in ICV. This may imply that the neurodevelopmental trajectories leading to brain anomalies in schizophrenia or bipolar disorder are distinct

    Comparison of three-dimensional ultrasound and magnetic resonance imaging diagnosis in surgically proven Mullerian duct anomaly cases

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    WOS: 000371187300005PubMed ID: 26699099Objective: To determine and compare the diagnostic accuracy of 3-dimensional ultrasound (3D US) and magnetic resonance imagining (MRI) in patients with surgically diagnosed Mullerian duct anomaly (MDA). Study design: Charts of patients with MDA were retrospectively evaluated. Patients who underwent both laparoscopic and hysteroscopic surgery and had 3D US and MRI examinations were included in the study. The diagnoses achieved via 3D US and MRI were compared with the surgical diagnoses to determine the diagnostic accuracy of these imagining techniques. Results: Twenty-nine patients were included in the study. Three-dimensional ultrasound detected 28 out of 29 (96%) patients correctly. Only one patient was diagnosed with a uterine septum instead of uterine arcuatus. Magnetic resonance imaging detected 23 out of 29 patients correctly (79%). The Kappa indexes of the 3D US and MRI were 0.896 and 0.592, respectively. Conclusion: Our results indicate that 3D US has a higher diagnostic accuracy level than MRI in evaluating MDA, especially when used in experienced hands. However, additional, well-designed studies are needed to better compare the diagnostic accuracy of the 3D US and MRI. Crown Copyright (C) 2015 Published by Elsevier Ireland Ltd. All rights reserved

    Cortical thickness and VBM in young women at risk for familial depression and their depressed mothers with positive family history

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    WOS: 000377354600001PubMed ID: 27136662It has been demonstrated that compared to low-risk subjects, high-risk subjects for depression have structural and functional alterations in their brain scans even before the disease onset. However, it is not known if these alterations are related to vulnerability to depression or epiphenomena. One way to resolve this ambiguity is to detect the structural alterations in the high-risk subjects and determine if the same alterations are present in the probands. In this study, we recruited 24 women with the diagnosis of Major Depressive Disorder (MDD) with recurrent episodes and their healthy daughters (the high-risk for familial depression group; HRFD). We compared structural brain scans of the patients and HRFG group with those of 24 age-matched healthy mothers and their healthy daughters at similar ages to the HRFD group; respectively. Both cortical gray matter (GM) volume and thickness analyses revealed that HRFD daughters and their MDD mothers had similar GM differences in two regions: the right temporoparietal region and the dorsomedial prefrontal cortex. These results suggested that the observed alterations may be related to trait clinical and neurophysiological characteristics of MDD and may present before the onset of illness. (C) 2016 Elsevier Ireland Ltd. All rights reserved.Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [109S134]This work was supported by The Scientific and Technological Research Council of Turkey (Project Number 109S134)

    Monitoring geographical differences in illicit drugs, alcohol, and tobacco consumption via wastewater-based epidemiology: Six major cities in Turkey

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    A national wastewater-based epidemiology (WBE) monitoring campaign has been initiated to determine the trends in drug consumption in Turkey since 2019. This study aimed to present the wastewater monitoring results for four periods in 2019 for six major cities with 17 wastewater treatment plants. The study investigated heroin (HER), amphetamine (AMP), methamphetamine (METH), cocaine (COC), 3,4-methylenedioxymethamphetamine (MDMA), cannabis, alcohol, and tobacco to understand the temporal and geographical drug consumption trends. The results indicated a trend of regular cannabis use in all the cities. Considering geographical variations, the drug usage trends were not homogeneous within the country for any of the investigated drugs, except cannabis. HER consumption was predominant in Denizli (1042.48 mg/1000 inh/day), while Izmir and Antalya (154.10 and 79.56 mg/1000 inh/day, respectively) topped for COC consumption. Aydin had the highest consumption levels of AMP (90.03 mg/1000 inh/ day) and METH (358.13 mg/1000 inh/day), while MDMA consumption was the highest in Samsun (157.64 mg/1000 inh/day). Tobacco consumption was high in Aydin (8791.69 mg/1000 inh/day) and Antalya (5375.17 mg/1000 inh/ day), whereas alcohol consumption was higher in Bursa than in the other cities (53434.61 mL/1000 inh/day). There were no statistically significant differences in the weekend consumption levels of the investigated drugs among these six cities. Although this study included the results of 1 year of consumption monitoring, the data confirms internationally published information on the drug trafficking routes of conventional drugs in this region, especially the Heroin-Balkan route. Results from further sampling will enable accurate evaluation of global drug consumption and trafficking, in addition to alcohol and tobacco use. (c) 2021 Elsevier B.V. All rights reserved

    Small Frontal Gray Matter Volume in First-Episode Depression Patients

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    WOS: 000281709900001PubMed ID: 20818506Objective: Brain imaging studies have shown that depressed individuals suffer from inadequate frontal lobefunctions vis a vis smaller frontal lobes. The effects of depression's recurrent nature and long-term antidepressant treatment are not definitely known. This study aimed to examine frontal lobe volume at the onset of clinical depression by including first-episode drug-naive depressed patients. Method: The study included 23 first-episode drug-free major depression patients diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) and 28 healthy age- and sex-matched controls. Cranial magnetic resonance (MR) images were obtained in both groups using a 1.5 Tesla device. Gray and white matter volumes in the frontal lobes were measured using the Medical Image Processing Analysis and Visualization (MIPAV) computer program. Results: Frontal gray matter volume in the patients was lower than that in the control group. White matter and total intracranial volume did not differ between the 2 groups. Small gray matter volume was not correlated with the duration or severity of illness. Conclusion: The results of this study indicate that frontal lobe gray matter volume is low in first-episode depressed patients and is independent of both illness severity and duration. This result suggests that the observed changes in the frontal lobe could have occurred before the clinical symptoms of depression were observed

    Hippocampal shape alterations in healthy young women with familial risk for unipolar depression

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    WOS: 000427666900002PubMed ID: 29367060Background: Although reduced hippocampal volume (HCV) is a common finding in depression, it is unclear whether the structural alterations leading to reduction of HCV are pre-existing risk factors before the onset of clinical symptoms or a cumulative process that begins with the onset of clinical symptoms. The aim of the present study was to understand the anatomical status of the hippocampus prior to the clinical symptoms in subjects with high familial risk for depression. Methods: Twenty-seven young women (mean age: 22.3 +/- 2.1 years) who were at high risk for familial unipolar depression and 26 age- and gender-matched healthy controls (mean age: 22.1 +/- 2.1 years) with low familial risk for depression were included in the study. Total hippocampal volumes were measured by manual tracing. For 3D shape differences, the spherical harmonic basis functions (SPHARM) software was used. The segmented images were parameterized, and the point-to-point based group difference was compared by the Hotelling's T-squared test with total brain volume and Beck Depression Scale as covariates. Results: Although there was no difference in overall HCVs, shape analyses revealed a contracted area on the Cornu Ammonis (CA) 1 region of the right hippocampus head in the high-risk group compared to the low-risk group. Cross-sectional design and small sample size, including only females, were the main limitations of this study. Conclusion: This study with shape analyses provided data suggesting that local structural hippocampal alterations in the CA1 region might be associated with depression vulnerability in women at high risk. (C) 2018 Elsevier Inc. All rights reserved.Scientific and Technological Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [109S134]This work was supported by The Scientific and Technological Research Council of Turkey (project number 109S134)

    Mutational landscape of severe combined immunodeficiency patients from Turkey.

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    Severe combined immunodeficiency (SCID) has a diverse genetic aetiology, where a clinical phenotype, caused by single and/or multiple gene variants, can give rise to multiple presentations. The advent of next-generation sequencing (NGS) has recently enabled rapid identification of the molecular aetiology of SCID, which is crucial for prognosis and treatment strategies. We sought to identify the genetic aetiology of various phenotypes of SCIDs and assessed both clinical and immunologic characteristics associated with gene variants. An amplicon-based targeted NGS panel, which contained 18 most common SCID-related genes, was contumely made to screen the patients (n = 38) with typical SCID, atypical SCID or OMENN syndrome. Allelic segregations were confirmed for the detected gene variants within the families. In total, 24 disease-causing variants (17 known and 7 novel) were identified in 23 patients in 9 different SCID genes: RAG1 (n = 5), RAG2 (n = 2), ADA (n = 3), DCLRE1C (n = 2), NHEJ1 (n = 2), CD3E (n = 2), IL2RG (n = 3), JAK3 (n = 4) and IL7R (n = 1). The overall success rate of our custom-made NGS panel was 60% (39.3% for NK+ SCID and 100% for NK- SCID). Incidence of autosomal-recessive inherited genes is more frequently found in our cohort than the previously reported populations probably due to the high consanguineous marriages in Turkey. In conclusion, the custom-made sequencing panel was able to identify and confirm the previously known and novel disease-causing variants with high accuracy
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