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The Effect of High Salt Diet on Anxiety-Depression-Like Behaviors and Cognitive Function in Female and Male Mice
No full textThe Effect of High Salt Diet on Anxiety-Depression-Like Behaviors and Cognitive Function in Female and Male Mice..
Estimating streamflow of the Kızılırmak River, Turkey with single- and multi-station datasets using Random Forests
Full text linkPredicting missing historical or forecasting streamflows for future periods is a challenging task. This paper presents open-source data-driven machine learning models for streamflow prediction. The Random Forests algorithm is employed and the results are compared with other machine learning algorithms. The developed models are applied to the Kızılırmak River, Turkey. First model is built with streamflow of a single station (SS), and the second model is built with streamflows of multiple stations (MS). The SS model uses input parameters derived from one streamflow station. The MS model uses streamflow observations of nearby stations. Both models are tested to estimate missing historical and predict future streamflows. Model prediction performances are measured by root mean squared error (RMSE), Nash–Sutcliffe efficiency (NSE), coefficient of determination (R2), and percent bias (PBIAS). The SS model has an RMSE of 8.54, NSE and R2 of 0.98, and PBIAS of 0.7% for the historical period. The MS model has an RMSE of 17.65, NSE of 0.91, R2 of 0.93, and PBIAS of -13.64% for the future period. The SS model is useful to estimate missing historical streamflows, while the MS model provides better predictions for future periods, with its ability to better catch flow trends
Turkish Teachers’ Competence in Creating Digital Stories with Web 2.0 Tools
Full text linkBu araştırma, Türkçe öğretmenlerinin web 2.0 araçlarıyla dijital hikâye hazırlayıp kullanabilme yetkinlik düzeylerini belirlemeyi ve bu yetkinlikleri farklı değişkenler açısından incelemeyi amaçlamaktadır. Araştırma, tarama modellerinden ilişkisel tarama modelinde gerçekleştirilmiştir. Araştırmanın evrenini, 2021-2022 eğitim-öğretim yılında 47 farklı ilde Millî Eğitim Bakanlığına bağlı resmî okullarda görev yapan Türkçe Öğretmenleri, örneklemini ise bu okullarda görev yapan 195 Türkçe öğretmeni oluşturmaktadır. Katılımcılar seçkisiz örnekleme yöntemlerinden basit seçkisiz örnekleme yoluyla belirlenmiştir. Araştırmanın verileri “Kişisel Bilgi Formu” ve “Dijital Hikâye Araçları Kullanımı Yetkinliği Ölçeği” ile toplanmıştır. Araştırmadan elde edilen bulgulara göre öğretmenlerin web 2.0 araçlarıyla dijital hikâye hazırlayıp kullanabilme yetkinlik düzeylerinin orta seviyede olduğu tespit edilmiştir. Araştırmadan elde edilen bir başka bulguya göre öğretmenlerin dijital hikâye oluşturma yeterlik puanı ile cinsiyet, öğretmenlerin yaşı ve öğrenim durumları arasında anlamlı bir ilişki tespit edilmemiştir. Bununla birlikte dijital hikâye oluşturma yeterliği ile bilgisayarı kullanma düzeyi arasında orta seviyede pozitif yönlü bir ilişki olduğu, dijital hikâye oluşturma yeterliği ile derslerde dijital teknolojileri kullanma durumu arasında ise zayıf düzeyde pozitif yönde anlamlı bir ilişki olduğu bulgusuna ulaşılmıştır.This research aims to determine the competency levels of Turkish teachers in preparing and using digital stories with Web 2.0 tools and to examine these competencies in terms of different variables. The research was carried out in relational scanning model, one of the scanning models. The population of the research consists of Turkish teachers working in public schools affiliated to the Ministry of National Education in 47 different provinces in the 2021-2022 academic year, and the sample consists of 195 Turkish teachers working in these schools. Participants were determined by simple random sampling, one of the random sampling methods. The data of the research were collected with the “Personal Information Form” and “Digital Story Tools Usage Competence Scale”. According to the findings obtained from the research, it has been determined that the teachers’ level of competence in preparing and using digital stories with Web 2.0 tools is at a moderate level. According to another finding obtained from the research, there was no significant relationship between teachers’ digital story creation proficiency score and gender, teachers’ age and educational status. However, it was found that there was a moderately positive relationship between the proficiency of creating a digital story and the level of using the computer, and a weakly positive and significant relationship between the proficiency of creating a digital story and the use of digital technologies in the lessons
Transformation of bonds and redistribution of partial states of valence electrons at α(С23)-WGe 2 →β(С11b )-WGe 2 high-pressure polymorphic transformation
No full textThe electronic properties and phase transition of β(C11b)-WGe2 and α(C23)-WGe2 phases were investigated via x-ray emission spectroscopy method and first-principles calculations. The analysis of the comparison of the partial energy distributions of the valence electrons of the β(C11b)-WGe2 and α(C23)-WGe2 phases was also studied. The transformation of interatomic bonds during the polymorphic transition α(C23)-WGe2→β(C11b)-WGe2 under comprehensive compression was proposed. The first-principles calculations showed that the phase transition from the α(C23)-WGe2 phase to the β(C11b)-WGe2 phase occurs under high pressure. Furthermore, the electronic structure calculations indicate that the considered phases are metallic in nature. The results have revealed that the fine-structure peculiarities of the WLβ 5- and GeKβ 2-emission bands match well with the main peaks of the partial densities of the W d- and Ge p- electronic states for the both phases
Sensor using a photo-acoustic absorption cell with two perpendicular acoustic resonators to analyze multiple molecules
No full textAn ultra-high sensitivity multi-molecule sensor based on a photo-acoustic cell with two perpendicular acoustic resonators and a common microphone has been reported. In this work, a 4.5 μm distributed-feedback quantum cascade laser and a 1.5 μmexternal cavity diode laser (EC-DL)were used as optical excitation sources. Considering the spectral ranges of the lasers used, it is possible to analyze eight molecules (QCL V N2Oand CO2, EC-DL:H2O, H2S, NH3, CO, CH4, and C2H2). The N2O molecule was used to evaluate the performance of the photo-acoustic spectroscopy (PAS)-based sensor. A sensitivity of 0.073 V/ppm and a linearity of 0.99 were found by analyzing the PAS signal as a function of N2O concentration at 2237.656 cm-1. The long-term performance of the sensor was determined by performing an Allan deviation analysis. A minimum detection limit of 9.8 ppb for 90 s integration time was achieved. The simultaneous multi-trace gas detection capability was verified by measurement of N2O, CO2, and H2O. Depending on the coarse/fine-tuning ranges of the lasers used, the number of molecules analyzed can be further increased. Such a sensor could provide simultaneous diagnosis of many diseases through an analysis of breath air and simultaneous monitoring of the most important greenhouse gases
Statistical techniques vs. machine learning models: a comparative analysis for exchange rate forecasting in fragile five countries
Full text linkIn 2013, the Federal Reserve (Fed) announced the end of its expansionary monetary policy, which had a significant impact on certain countries. These countries, colloquially referred to as the "fragile five", were heavily dependent on financial capital flows, which led to deviations from inflation targets due to the exchange rate pass-through effect. Consequently, monetary authorities and other financial actors need accurate exchange rate forecasts to mitigate these deviations and improve the effectiveness of monetary policy. This study aims to forecast the exchange rates of the fragile five countries using both traditional statistical methods and machine learning techniques. The traditional statistical methods used in this study include Naïve Drift, Theta, Holt's Exponential Smoothing and ARIMA models, while the machine learning methods include RNN, LSTM, GRU and CNN architectures. The results show that machine learning methods outperform traditional statistical methods in terms of prediction accuracy for all countries. While statistical methods show a directional accuracy rate between 47% and 60%, RNN, one of the machine learning models, shows an accuracy rate between 80% and 90%. Overall, these results suggest that machine learning methods can provide more accurate exchange rate forecasts for the fragile five countries than traditional statistical methods. These findings may be valuable for monetary authorities and financial actors seeking to improve the effectiveness of monetary policy in these countries
Morphometric evaluation of the human corpus callosum using magnetic resonance imaging: Sex difference and relationship to age and intracranial size
No full textThe objective of this study was to determine the normal values of corpus callosum (CC) subregions in healthy adult individuals in our population using magnetic resonance imaging (MRI) and to reveal gender differences during normal aging. Material and Methods: We performed the measurements of certain CC dimensions in 104 (44 males and 60 females) individuals. MRI imaging device was used for the measurements. The subregions of CC were measured with the midsagittal images. After the measurements of CC and its sections' (rostrum [R], genus [G], anterior body, posterior body, isthmus [I], and splenium [S]), length (L), width (W), and area (A) were carried out, the intracranial volume (ICV) and intracranial area (ICA) values were calculated. The Student's t-test and Pearson correlation test were used for statistical analysis. Results: Morphometric data of length, width, area, ICV, and ICA were collected. No significant difference was identified in CC morphometry by age among the patients (P > 0.05). Indicating longer diameters in males, the differences between the genders were significant (P < 0.05). Moreover, the mean of R-L, G-A, and G-W measurements was found significant between the age groups (P < 0.001). Conclusion: Sexual dimorphism in the CC is not a simple artifact of sex differences in brain size and may reflect differences in connectivity necessitated by differences in brain sizes
Multi-Criteria Decision Analysis for Optimizing CO2 and NH3 Removal by Scenedesmus dimorphus Photobioreactors
Full text linkNumerous technologies have been investigated for mitigating air pollutant emissions from swine barns. Among them, algal photobioreactors (PBRs) can remove and utilize air pollutants such as CO2 and NH3 from barn exhaust. However, a challenge to PBR operation is that it involves multiple system input parameters and output goals. A key question is then how to determine the appropriate CO2 and NH3 concentrations in this case. Conventional statistical methods are inadequate for handling this complex problem. Multi-criteria decision-making (MCDM) emerges as a practical methodology for comparison and can be utilized to rank different CO2–NH3 interactions based on their environmental and biological performance. By employing MCDM methods, producers can effectively control the ratio of CO2 and NH3 concentrations, enabling them to identify the optimal range of operating parameters for various housing types, ensuring efficient pollutant mitigation. In this study, a multi-criteria decision-making (MCDM) approach was employed to support operation management. Specifically, influent CO2 and NH3 concentrations were optimized for three scenarios (the best biological, environmental, and overall performance), using a combination of two MCDM techniques. This study is anticipated to facilitate the system analysis and optimization of algae-based phytoremediation processes
Center-Right Politics on the axis of Cold War Dynamics: The case of The Justice Party
Full text linkBu çalışma, merkez-sağın 1980 öncesi konjonktürde geliştirdiği siyaset ve kamusal söylemlerde Soğuk Savaş’a özgü dinamiklerin etkilerini ortaya koyma amacındadır. Çalışmanın zaman sınırını 1960-1980 arası dönem oluştururken; odaklanılan merkez-sağ parti ve hareket ise Adalet Partisi’dir. AP, özellikle tek başına iktidar olduğu 1960’ların ikinci yarısında, ekonomik kalkınma ve merkez sağa özgü esnek denge siyasetinin izlerini taşıyordu. Ancak 1970’lere geldiğimizde Amerikan 6. Filosu’nun Türk limanlarına gelişi ve Kıbrıs meselesi etrafında yükselen anti-Amerikanizm dalgası, siyasal alandaki işleyişe yeni boyutlar kazandırdı. Bu dönemde sol kanat gençlikte başlayan protest örgütlenmelere karşı, Türk sağının genç kuşaklarında da radikal hareketler ivme kazandı. Giderek hareketlilik kazanan yeni ideolojik fay hatları, Ecevit etrafında sol siyasete iktidar kanallarını da açıyordu. Söz konusu süreç sonunda, AP’nin tarz-ı siyaseti de, keskin ideolojik hatlara doğru çekilir. Bu doğrultuda anti-komünizm, AP elitlerinin kamusal söylem ve politikalarında merkezi dinamiği oluşturdu. Aynı zamanda AP’nin “Milliyetçi Cephe Hükümetleri”ndeki yeni paydaşlarıyla İslamizasyon ve milliyetçiliğe açılan kültür politikaları, bu dönüşüme derinlik kazandırdı.This study aims to reveal the effects of Cold War-specific dynamics in the politics and public discourses developed by the centre-right in the pre-1980 conjuncture. While the period between 1960 and 1980 constituted the time limit of the study; the center-right party and movement focused on is the Justice Party. Especially in the second half of the 1960s, when it was in power alone, the AP carried the traces of economic development and a flexible balance policy peculiar to the centre-right. However when we got to the 1970s, the American 6. The arrival of the Fleet in Turkish ports and the wave of anti-Americanism that has risen around the Cyprus issue have given new dimensions to the functioning of the political sphere. In this period, extreme movements gained momentum in the young generations of the Turkish right, against the protest organizations that started in the left-wing youth. The new ideological fault lines, which were becoming increasingly mobile, were also opening up channels of power to left-wing politics around Ecevit. At the end of the process in question, the political style of the AP is also drawn towards sharp ideological lines. In this direction, anti-communism formed the central dynamic in the public discourse and policies of the AP elites. At the same time, the AP’s cultural policies towards Islamization and nationalism with its new stakeholders in the “Nationalist Front Governments” have given depth to this transformation
Construction and application of MgAl LDH-Schiff base-supported palladium nanocatalyst for Heck reactions and reduction of organic pollutants
No full textIn this study, a novel nanostructured Pd NPs@MgAl LDH-Schiff base-supported catalyst system was developed through a deposition of Pd NPs on the modified MgAl-layered double hydroxide (MgAl LDH). Structural/morphological features of Pd NPs@MgAl LDH-Schiff base nanocatalyst were investigated by XRD, FESEM, BET, FTIR, EDS, and TEM analyses. It was found that Pd NPs with an average particle size of about 14.50 ± 1.24 nm were successfully produced without agglomeration. The catalytic performance of the prepared Pd NPs@MgAl LDH-Schiff base as a heterogeneous nanocatalyst was subsequently tested in both Heck reaction (HCR) and reductions of 4-nitrophenole (4-NP) and 2-nitroaniline (2-NA). The tests revealed that Pd NPs@MgAl LDH-Schiff base nanocatalyst effectively coupled HCR of styrene and different aryl iodides/bromides by producing reaction yields between 90 and 98% for 3–5 h. In addition, Pd NPs@MgAl LDH-Schiff base nanocatalyst confirmed that it had significant catalytic power by converting 4-NP and 2-NA to 4-aminophenole (4-AP) and 2-phenylenediamine (2-PDA) in 50 s and 45 s, respectively. The rate constants for the reductions of 4-NP and 2-NA in the presence of Pd NPs@MgAl LDH-Schiff base nanocatalyst were determined as 0.017 s−1 and 0.023 s−1, respectively. Due to its heterogeneous nature and the strong synergistic interaction between Pd NPs and prepared MgAl LDH-Schiff base as support, Pd NPs@MgAl LDH-Schiff base nanocatalyst was easily recovered and reapplied for six consecutive runs with unchanged structural/morphological features