31451 research outputs found
Sort by
Is Nature of Inflation Co-Movement Time-Varying? Insights From a Dynamic Factor Model
No full textNazlioglu, Saban/0000-0002-3607-3434The purpose of this study is to examine whether inflation co-movement has a time-varying behavior. We estimate a dynamic factor model with time-varying variances and obtain variance decomposition for G7 countries from 1970 to 2023. The results reveal that (i) inflation co-movement tends to change with global shocks, with a more synchronized pattern during global financial crisis and COVID-19; and (ii) it tends to cluster across countries after COVID-19, with an increase in US, Canada, and Japan and a decrease in European countries (France, Germany, Italy, and UK). These findings hence provide new insights on time-varying inflation co-movement
Erişkin bireylerin 3-D MR görüntülerinde 3D slicer programı kullanılarak pankreas hacminin ve boyutlarının incelenmesi
No full textAmaç: Bu çalışmadaki amacımız, cerrahi müdahalelerde cerrahlara yol göstermek ve hastalıklı bireylerde yapılan çalışma bulgularını sağlıklı bireylerin organ yapısıyla karşılaştırarak yorumda bulunma şansını yaratmak için 3D Slicer bilgisayar yazılımı sayesinde çok sayıdaki sağlıklı bireyde pankreas’ın hacmini ve boyutlarını belirleyip, pankreas morfolojisiyle ilgili özellikleri tanımlamaktır.
Gereç ve Yöntemler: 2016 yılından itibaren Pamukkale Üniversitesi Tıp Fakültesi Radyoloji Anabilim dalında arşivde bulunan batın ile ilgili 3D MR görüntüleri kullanılmıştır. 3D MR görüntüleri, 1,5 T (Ingenia; Philips Medical Systems, Best, the Netherlands, 2016) MRG cihazı kullanılarak elde edilmiştir. Bu görüntüler, 3D Slicer
5.2.1 programının yardımı ile üç boyutlu hale getirilip hacim ölçümü, alan ölçümü ve uzunluk ölçümü hesaplanmıştır.
2016 yılından itibaren erişkin bireylere ait görüntüler alınmıştır. Tip1 Diabet ve Tip2 Diabet hastalar, pankreas rezektomi yapılan hastalar gibi pankreas’ın hacmine etkisi olan hastalıklar çalışma grubuna dahil edilmemiştir.
Elde edilen veriler, SPSS 25.0 (IBM SPSS Statics 25 software (Armonk, NY: IBM Corp.)) paket programıyla analiz edilmiştir. Sürekli değişkenler, ortalama ± standart sapma ve kategorik değişkenler sayı ve yüzde olarak verilmiştir. İstatistiksel analiz için Mann Whitney U testi ve Kruskal Wallis Varyans analizi, Pearson ve Spearman korelasyon analizleri Ki kare analizi kullanılmıştır. Tüm incelemelerde p˂0.05 istatistiksel olarak anlamlı kabul edilmiştir.
Bulgular: Caput pancreatis’in uzunluğu ortalama 29,81±8,4 mm; corpus pancreatis’in ortalama uzunluğu 84,17±25,14 mm; cauda pancreatis’in uzunluğu 32,55±12,82 mm; pankreas’ın toplam uzunluğu 151,24±28,28 mm olarak hesaplanmıştır. Pankreas’ın toplam alanı 23029,01±16913,08 mm2; toplam hacmi 82086,62 ± 57433,63 mm3 olarak ölçülmüştür.
Sonuç: Bu çalışma cerrahi müdahalelerde cerrahlara yol göstermek ve hastalıklı bireylerde yapılan çalışma bulgularını sağlıklı bireylerin organ yapısıyla karşılaştırarak yorumda bulunma şansını yaratmak için 3D Slicer bilgisayar yazılımı kullanarak çok sayıdaki sağlıklı bireyde pankreas’ın boyutlarını ve hacmini belirlemiştir. Bu yöntemle ilk defa, sağlıklı yetişkin bireylerde pankreas morfolojisiyle ilgili özellikler tanımlanmıştır.Aim: Our aim in this study is being guide surgeons in surgical interventions and to create the opportunity to comment by comparing the findings of studies conducted on diseased individuals with the organ structure of healthy individuals, the 3D Slicer computer software is used to determine the volume and dimensions of the pancreas in a large number of healthy individuals and to define the features related to pancreatic morphology. Materials and Methods: 3D MR images of the abdomen found in the archives of Pamukkale University Faculty of Medicine, Department of Radiology since 2016 were used. 3D MR images were obtained using a 1.5 T (Ingenia; Philips Medical Systems, Best, the Netherlands, 2016) MRI device. These images were obtained in three dimensions with the help of the 3D Slicer 5.2.1 program accessed using an open access site, and volume, area and length measurements were calculated.
Images taken since 2016 must belong to adult individuals. Diseases affecting the volume of the pancreas, such as patients with Type 1 Diabetes and Type 2 Diabetes, patients who underwent pancreatic resectomy, were not included in the study group.
Analysis was performed with SPSS 25.0 (IBM SPSS Statics 25 software (Armonk, NY: IBM Corp.)) package program. Continuous variables are given as mean ± standard deviation and categorical variables are given as numbers and percentages. In examining the differences between the groups, when the parametric test assumptions were met, the significance test of the difference between two means and one-way variance analysis were used, and when the parametric test assumptions were not met, the Mann Whitney U test and Kruskal Wallis variance analysis were used. In examining the relationships between numerical data, Pearson or Spearman correlation analyses were used. The relationships between continuous variables were examined with Spearman or Pearson correlation analyses. The differences between categorical variables were examined with Chi-square analysis. In all examinations, p˂0.05 was accepted as statistically significant.
Results: The average length of the caput pancreatis was calculated as 29.81±8.4 mm; the average length of the corpus pancreatis was 84.17±25.14 mm; the length of the cauda pancreatis was 32.55±12.82 mm; and the total length of the pancreas was 151.24±28.28
mm. The total area of the pancreas was measured as 23029.01±16913.08 mm2; and the total volume was measured as 82086.62±57433.63 mm3.
Conclusion: This study determined the dimensions and volume of the pancreas in a large number of healthy individuals using 3D Slicer computer software to guide surgeons in surgical interventions and to create the opportunity to interpret the findings of studies conducted on diseased individuals by comparing them with the organ structure of healthy individuals. The characteristics related to pancreatic morphology in healthy adult individuals were defined for the first time with this method
Catanionic synergetic effect of sodium dodecyl sulphate and cetyl trimethyl ammonium bromide surfactants on the electrochemical performance of porous carbon anodes in lithium-ion batteries
No full textCarbon-derived materials are suitable for use as anodes in lithium-ion batteries due to low production cost and abundance. However, there is a need to improve the electrochemical performance with various modifications due to the limited capacity. In this study, a porous carbon is modified with anionic sodium dodecyl sulphate (SDS) and cationic cetyl trimethyl ammonium bromide (CTAB) surfactants and prepared as an anode for use in lithium-ion batteries. Morphological and structural properties change with the addition of surfactants, and the use of only one or two of them together has different effects. The morphology formed by adding only SDS is homogeneous and only CTAB is heterogeneous. When both surfactants are used SDS also provides homogeneous dispersion of CTAB. The changes in I2D/IG and ID/IG ratios obtained from Raman analyses show that the layer arrangement and the ratio of defects in the structure have changed. Electrochemical performances with different surfactant amounts are compared by using charge/discharge tests, cyclic voltammetric tests and differential capacity analysis (dQ/dV). The combined use of SDS and CTAB creates a synergetic effect (catanionic) and increases the capacity nearly 1.5 times by improving wetting, amount of lithium-ion storage areas and reducing the irreversible loss of capacity caused by solid electrolyte interface.Eskisehir Technical University Scientific Research Projects Unit [1709F501]We would like to thank Prof. Dr. Feridun Ay for allowing us to use the Raman spectroscopy equipment. We would also like to thank Eskisehir Technical University Scientific Research Projects Unit, with a grant number of 1709F501, for battery assembly consumables and electrochemical performance tests
A Comparison of Clinical Characteristics and Course Predictors in Early- and Childhood-Onset Schizophrenia
No full textHangul, Zehra/0000-0001-8397-5636; Sahin, Berkan/0000-0003-4699-3418; Ayaydin, Hamza/0000-0003-4909-0070; Bozkurt, Abdullah/0000-0002-8359-6131; Cobanoglu Osmanli, Cansu/0000-0002-9631-1262; Onal, Bedia Sultan/0000-0003-2818-4764AimThe aim of this study was to compare the clinical characteristics of childhood-onset schizophrenia (COS) and early-onset schizophrenia (EOS) during the first- episode psychosis and the stable period, to examine psychopharmacological treatment approaches, and to investigate potential predictive factors for prognosis.MethodsDemographic, clinical, and psychopharmacological therapy data for 31 patients diagnosed with COS and 66 with EOS were retrieved from the file records in this multicenter study. Symptom distribution and disease severity and course were evaluated twice, in the acute psychotic stage and in the latest stable phase, during follow-up using the positive and negative syndrome scale (PANSS) and clinical global impression (CGI) scales.ResultsA statistically significant difference was observed between the groups' CGI improvement rates and median last stable stage PANSS positive, negative, and general psychopathology symptom scores (p = .005, p = .031, p = .005, and p = .012, respectively). Premorbid neurodevelopmental disorder and obsessive-compulsive disorder and comorbidities were more common in the COS group (p = .025 and p = .030, respectively), and treatment required greater multiple antipsychotic use in that group (p = .013). When the independent variables affecting the difference between pre- and post-treatment PANSS scores were examined using linear regression analysis, the model established was found to be statistically significant (F = 5.393; p = .001), and the group variable (p = .024), initial disease severity (p = .001), and socioeconomic level (p = .022; p = .007) emerged as predictive factors for the disease course.ConclusionAlthough early diagnosis and treatment is an important factor in improving prognosis in schizophrenia, more specific predictors for schizophrenia need to be identified. Additionally, preventive programs and pharmacological methods need to be developed in children with neurodevelopmental problems, particularly those from low socioeconomic status families.The authors thank the patients and their families who participated in the study
Ore and Gangue Mineral Textures, Fluid Inclusions, Mesoscopically Structured Quartz and Pyrite, and Their Bearing on the Genesis of Hydrothermal Breccias in the Low-Sulfidation Surnak Gold Deposit, Se Bulgaria
No full textThis paper provides comprehensive analyses of mineral microtextures, nanoparticulate electrum, defective crystal structures of key primary hydrothermal minerals - quartz and pyrite, the bulk sulfur isotopic composition of pyrite and marcasite, and fluid inclusions in hydrothermal quartz and calcite, all aimed at characterizing ore mineralization. The study primarily focuses on samples collected from a steep normal fault and its damage zone, which formed during hydrothermal brecciation, while also incorporating samples from other thinner brecciation zones. The data utilized in this study originate from the Surnak (or Sarnak) gold deposit located in the Eastern Rhodope Mountains of Southeast Bulgaria. This deposit, characterized as low-sulfidation, offers a distinctive geological context for exploring the hydrothermal processes associated with hydrothermal brecciation, colloidal, and mesocrystal formation. The unique microtextures and mesocrystal structures observed in quartz and pyrite crystal lattices offer valuable insights into the colloidal stage that the paleohydrothermal solution experienced during hydrothermal brecciation, pressure drop, and subsequent boiling. Bladed-textured calcite crystals, containing both vapor-rich and liquid-rich inclusions, provide direct evidence of fluid boiling. Fluid inclusion data from hydrothermal quartz further suggest the involvement of two distinct fluid types, each with different temperatures and salinities. Our findings point to a causal relationship between brecciation episodes, fluid boiling, nanoparticle nucleation, the colloidal stage, and the subsequent formation of mesocrystals. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024
Highly Sensitive Textile Pressure Sensors With Novel Hierarchical Architecture Based on Conductive Polymers, Silver Nanoparticles and Carbon Nanotubes
No full textOnar Camlibel, Nurhan/0000-0002-2647-4728Herein, we designed wearable, flexible, highly sensitive textile-based pressure sensor assemblies utilizing a piezoresistive working mechanism. The sensor assemblies were constructed using a composite of coated cotton woven or polyester knitted fabric encapsulated and stitched between two layers of polypropylene spunbond nonwoven fabric embroidered with stainless steel yarn serving, creating a robust and integrated sensing structure. As a component of the sensor assemblies, the cotton and polyester fabrics were subjected to a series of surface modifications involving coating with silver nanoparticles, a silica xerogel film formation through a sol-gel process, application of polypyrrole via chemical oxidative polymerization, followed by deposition of a layer of carbon nanotubes and polydimethyl siloxane utilizing a dip-coating method. The sensor assemblies employing conductive polyester knitting fabrics demonstrate remarkable sensing capabilities, including an extensive sensing range of 0 kPa-225 kPa, high sensitivity values of 30 kPa(-1), low detection limits of 125 Pa, fast response-recovery times of 120-80 ms and robust sensing stability exceeding 1000 cycles, respectively. Moreover, the sensor assemblies exhibited significant promise for real-time human motion monitoring, encompassing activities such as finger, wrist, elbow and knee bending; swallowing, walking and jumping. These sensor assemblies offer distinct advantages, including cost-effectiveness, ease of handling, straightforward production methods, and an environmentally friendly fabrication process
Evaluation and Classification of Non-Linear Loss on Uniaxial Compressive Strength of Building Stones Exposed To Weathering by Freeze-Thaw Cycles
No full textCold climates accelerate the weathering of building stones via freeze-thaw (FT) cycles. This situation causes natural stones to begin to lose their integrity and subsequently decreases their strength. This study was conducted to demonstrate the impact of FT cycles on the course of uniaxial compressive strength (UCS) on very large number of natural stone sample types. For this purpose, 46 sample groups were subjected to 4, 7, 10, 14, 20, 28, 35, 56, 70, and 84 FT cycles under laboratory conditions, and UCS values were determined at the end of cycles. Additionally, ultrasonic P-wave velocities (VP) were measured in three directions on each fresh cubic sample, and the anisotropy coefficient (CA) was calculated. The effect of anisotropy to the strength loss of natural stones due to FT cycles was evaluated by the CA coefficients. Results suggested that the non-linear UCS loss, notably up to 35%, especially for the stones having greater than 5% open porosity (n). In addition, it has been revealed that sample groups with calculated CA coefficients above 15% are more prone to deterioration due to FT cycles. The Frost Resistance Index (FRI), defined as the ratio of the UCS value obtained after a specific FT cycle to the UCS value obtained on the fresh sample, was calculated for all groups at the end of respective cycles. A generalized classification system consisted of "very high", "high", "moderate", "low" and "very low" classes based on the FRI parameter for deteriorated building stones has been proposed for practice.Pamukkale niversitesi [2021FEBE002]; Pamukkale University Scientific Research Projects Coordination UnitThis study was supported by the Pamukkale University Scientific Research Projects Coordination Unit under project no of 2021FEBE002. The authors are thankful to Dr. Tamer Koralay (Pamukkale University) for his contribution in petrographic analyses
Affective Modulation of Emotional Reactivity in Euthymic Patients With Bipolar Disorder
No full textBackground: Affective modulation of startle reflex (AMSR) is a widely used experimental tool for assessing emotional reactivity. Previous research has shown inconsistent findings of emotional reactivity in amplitude in bipolar patients (BP). This study examined emotional reactivity (ER) in euthymic BP compared to healthy controls using both subjective and objective measures. Method: This study compared ER between 33 euthymic BP (I and II) and 35 healthy controls. Subjective experiences, valence, and arousal scores were assessed using the Self-Assessment Manikin. Objective measures included startle reflex parameters - amplitude, area, and latency - from the orbicularis oculi muscle via electromyography. To assess the AMSR, pictures of varying emotional valences from the International Affective Picture System were used during acoustic stimulation. Results: A significant picture category effect was observed in the subjective picture evaluation; however, no substantial group effect or picture category-group interaction was detected. In the controls, picture categories exerted a significant effect on amplitude, but did not in euthymic BP. A linear pattern of startle amplitude across different picture categories was evident in the control group but not in patients. Analyses of the area did not reveal significant group differences. Onset latency was also similar between groups. Conclusion: This study indicates impaired emotional processing in euthymic individuals with bipolar disorder, as shown by altered startle reflex measurements. Future research with larger samples and consideration of bipolar disorder subtypes is needed to explore these findings further
Sex Differences in Clinical and Polysomnographic Features of Obstructive Sleep Apnea: the Turkish Sleep Apnea Database (turkapne) Cohort
No full textBackground: Previous reports from relatively small clinical cohorts have suggested that the clinical presentation of obstructive sleep apnea (OSA) differs between men and women. Objective: We aimed to explore sex differences in clinical and polysomnographic features of OSA in a large nationwide registry. Methods: Participants from the ongoing Turkish Sleep Apnea Database (TURKAPNE) Study from 34 centers were included in the current analysis. OSA was defined as an apnea-hypopnea index (AHI) ≥5 events/hour and was classified as mild, moderate, and severe according to AHI cut-offs 5, 15, and 30 events/hour, respectively. Results: In all, 7130 patients (2259 women) were included. OSA was observed in 6323 (88.7 %), of whom 70.2 % were male and 29.8 % were female. In the OSA group, women were older (56.7 ± 11.9 vs. 49.5 ± 11.3 years; p 0.001) and more obese (body mass index 34.3 ± 7.2 vs. 31.4 ± 5.6 kg/m2; p 0.001) and had lower AHI (29.8 ± 24.1 vs. 36.8 ± 26.2 events/h; p 0.001) than men. Loud snoring and witnessed apnea were more common in men than in women whereas women were more frequently presented with insomnia, headache, and mood changes. Women had significantly less total sleep time, less sleep efficiency, and longer sleep latency compared with men (p 0.001 for each). Additionally, comorbid diseases such as diabetes mellitus, hypertension, asthma, psychiatric disorders, hypothyroidism as well as drug use were more common in women than in men independent of age and obesity (p 0.05 for each). Conclusions: Our results suggest significant sex differences in clinical and polysomnographic features in this nationwide Turkish adult population. Women with OSA have more symptom burden and comorbidities despite having a less severe AHI. © 2024 The AuthorsBundesministerium des Innern, für Bau und Heimat, BMI; ResMed Foundation; Data Monitoring Board; Turkish Thoracic Societ
What Drives House Prices in Turkey? Evidence From Bayesian Svar Model
No full textTurkey has experienced one of the largest rises in house prices in the world, particularly after the COVID-19. Given the entangled relationship between house prices, macroeconomics, and financial markets, it is crucial to understand the causes of house price hikes from both academic and policy perspectives. This study aims to identify the determinants of house prices in Turkey. The analysis employs a Bayesian sign- and zero-restricted Structural Vector Autoregression (SVAR) model, utilizing monthly data spanning the period from January 2011 to December 2023. The model incorporates six shocks considered to affect house prices: housing supply, housing demand, credit conditions, mortgage rates, exchange rates, and market sentiment. The findings reveal that housing supply, mortgage rates and credit conditions are the primary drivers of house prices in Turkey. Prior to 2018, housing supply shocks accounted for nearly half of the observed increase in house prices. However, in the post-2018 period, mortgage rates and credit conditions emerged as the predominant drivers of house price dynamics. Moreover, consumer sentiment and exchange rate fluctuations also significantly contribute to house price variations. These findings offer valuable policy insights for mitigating the risk of housing market booms