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Vrangel’in Güney Rusya hükümeti: Kırım’da beyaz rejimin meşruiyet arayışı, toprak reformu ve devletleşme denemesi (1920)
No full textThis article examines the Government of South Russia (Pravitel'stvo Yuga Rossii), established under General Pyotr Nikolaevich Wrangel in Crimea between April and November 1920, through the lenses of political legitimacy, land reform, and state-building within the broader context of the Russian Civil War. The study is centered on four research questions: why Wrangel's administration failed to generate durable popular support; what structural and administrative constraints limited the social impact of the land reform decree of 7 June 1920; why international recognition efforts collapsed in the face of British and French realpolitik and their evolving relations with Soviet Russia; and which organizational, logistical, and strategic factors led to the military defeat of the regime. The theoretical framework combines Max Weber's typology of legitimacy to assess authority-building practices and political discourse; Theda Skocpol's structural constraints approach to evaluate the military, economic, and social limitations of the regime; and Charles Tilly's war-state formation model to analyze the government's attempts to centralize administration and mobilize resources under wartime conditions. Together, these perspectives reveal that despite its short lifespan, Wrangel's regime pursued multiple, albeit uneven, experiments in counterrevolutionary state formation. Methodologically, the article adopts the historical analysis approach and evaluates primary sources-including decrees, administrative correspondence, statistical reports, implementation records of the land reform, British and French diplomatic telegrams, contemporary newspapers, legal documents, and Wrangel's memoirs-from State Archive of the Russian Federation (GARF), Russian State Military-Historical Archive (RGVIA) and Russian State Military Archive (RGVA) archives using internal and external criticism. These materials allow for a reassessment of certain widely repeated claims in the literature, such as the presumed total failure of the land reform or the notion that Western diplomatic engagement ceased entirely after mid-1920. The findings indicate that Wrangel's efforts to construct legitimacy were not limited to charismatic leadership; archival evidence shows that village committees were established in several regions and that the reform generated limited but observable local responses. Yet frequent policy revisions, administrative shortages, and the dominance of military imperatives undermined the formation of a stable social base. On the international level, British and French documents reveal that diplomatic contacts continued, though deliberately restrained, as both powers moved toward recognizing Soviet Russia. Militarily, the collapse stemmed not only from the Red Army's superior manpower and logistics but also from contracting supply lines, rising attrition, Crimea's structural defensibility limits, and coordination problems within the White administration. Ultimately, the article argues that Wrangel's regime should be understood not merely as a failed military enterprise but as a short-lived and structurally constrained attempt at counterrevolutionary state-building. By integrating archival evidence, the study offers a more comprehensive account of how legitimacy, reform capacity, and international alignment shaped state-building efforts under the extreme conditions of civil war
Interconnected freight markets: An ensemble learning and GAM approach to regional and international dry bulk shipping rates
No full textThe Baltic Dry Index (BDI) is widely regarded as a key generalizing indicator of shipping market conditions, supporting the analysis of historical market developments, the identification of current trends, and the forecasting of future market trajectories. Despite the index's widely acknowledged utility, it has historically paid limited attention to regional specificity. Consequently, the precise nature of its interconnections with fast-evolving regional freight markets remains insufficiently explained. Addressing this limitation, this study introduces a novel approach that integrates ensemble learning techniques with a Generalized Additive Model (GAM) to examine the complex relationships between regional and international freight rate indices, alongside macroeconomic and industry-specific variables. Using 14 variables from the Black Sea and Mediterranean regions over 413 weekly observations (2016-2024), the analysis identifies a triadic interaction pattern among freight indices that significantly shapes global shipping dynamics. Results indicate that regional indices not only respond to international market conditions but also exert measurable influence on global freight benchmarks, challenging the traditional assumption of unidirectional causality. The proposed triadic interaction framework sets a new perspective for shipping markets and enables more accurate regional forecasting. Specifically, the findings demonstrate how regional markets can influence global freight movements through interconnected spillover mechanisms. Shipowners and charterers should integrate region-specific indices into their risk assessment frameworks to better tailor hedging and operational strategies for target regions, moving beyond sole reliance on the generalized BDI
A critical checklist of Turkish freshwater fishes (2026)
No full textTürkiye, a key biogeographic bridge between Europe and Asia, has experienced major advances in taxonomic knowledge of its freshwater fishes, but existing faunal lists lag behind recent revisions. We present a revised checklist that compiles and standardises records using the latest IUCN assessments, published descriptions and revisions (to 2026), museum collections and expert-verified data. Unestablished introductions and strictly marine visitors were excluded. We recognise 390 freshwater fish species in 37 families, including 367 native species and 23 established non-native taxa, of which 202 natives (55%) are endemic to Türkiye. Species richness is concentrated in Leuciscidae (113 species), Nemacheilidae (59) and Cyprinidae (53), which together comprise 61.5% of the native fauna. At the catchment scale, total richness ranges from 11 species in the Van Basin to 65 in the Sakarya drainage, endemic richness was highest in Antalya (28 species) and non-native richness in the Sakarya drainage (10 species). The checklist provides updated nomenclature, distributions within Türkiye and standardised common names, establishing an agreed taxonomic baseline for biodiversity assessment, fisheries and conservation management
Phytochemical analysis and antimicrobial, antioxidant, and cytotoxic activities of Scorzonera aucheriana DC (Asteraceae)
No full textThe present study is mainly focused on the isolation and structure elucidation of four new (1–4), two known astragalin (5), and kaempferol-3,7-di-O- β -D-glucopyranoside (6) from the aerial parts of Scorzonera aucheriana DC. The structures of the isolated compounds were elucidated based on 1D and 2D NMR ( 1 H, 13 C/APT, COSY, HMBC, and HSQC), UV, FT-IR, and HRESI-MS data. The total phenol and flavonoid contents and the antioxidant activity of S. aucheriana crude methanol extract and its fractions (n -hexane, chloroform, ethyl acetate, and water) were investigated. The highest antioxidant activities against DPPH and FRAP were observed in the ethyl acetate fraction of S. aucheriana . The antimicrobial activity of the methanol extract, its solvent fractions, and isolated compounds (1–6) was evaluated against 10 microorganisms. The chloroform and ethyl acetate fractions exhibited antimicrobial activity against all tested microorganisms. Compounds 1–3 , 5 , and 6 exhibited anti-tuberculosis activity with MICs ranging from 30.9 μg/mL to 250 μg/mL. Compounds 2 , 4 , and 5 have also demonstrated moderate antifungal activity, with MICs ranging from 110 μg/mL to 765 μg/mL against C. albicans , a pathogenic yeast. Compounds 1–3 showed almost no cytotoxic activity in L-929 cells
Data Preparation for Analysis
No full textData Mining 2. Hafta Ders Notu Konusu : Data Preparation for Analysi
A novel ECG score for predicting left ventricular systolic dysfunction in stable angina: a pilot study
No full textBackground: Left ventricular systolic dysfunction (LVSD) is a major determinant of prognosis in patients with ischemic heart disease. Electrocardiography (ECG) is widely available, inexpensive, and may aid in identifying patients at risk. We hypothesized that a composite score derived from multiple established ECG markers could improve the detection of LVSD in patients with stable angina. Methods: In this single-center, cross-sectional study, 177 patients undergoing elective coronary angiography for stable angina were included. Patients were classified as LVSD-negative (n = 123) or LVSD-positive (n = 54) based on echocardiographic ejection fraction. ECG parameters, including fragmented QRS, pathologic Q waves, R-wave peak time, QRS duration, and frontal QRS–T angle, were assessed. Independent predictors of LVSD were identified using multivariate logistic regression. A composite ECG score was constructed by assigning one point to each abnormal parameter. Model robustness was evaluated using bootstrap resampling (1000 iterations) and 10-fold cross-validation. Results: Multivariable analysis identified prior stent implantation, fragmented QRS, pathological Q waves, R-wave peak time, frontal QRS–T angle (log-transformed), and QRS duration as independent predictors of LVSD. ROC analysis demonstrated good discriminatory performance for R-wave peak time (AUC 0.804), QRS duration (AUC 0.649), and frontal QRS–T angle (AUC 0.825) measurements. The composite ECG score showed a stepwise association with LVSD: a score of ≥2 yielded high sensitivity (88%) and negative predictive value (97%), whereas a score of ≥3 provided high specificity (100%) and positive predictive value (100%). Bootstrap resampling and cross-validation confirmed model stability and strong discriminatory performance (mean AUC, 0.964; accuracy, 0.91). Conclusions: A simple composite ECG score integrating multiple established ECG markers is associated with the robust detection of LVSD in patients with stable angina. Although not a substitute for echocardiography, this score may support early risk stratification and help identify patients who warrant further imaging evaluations. External validation in larger and more diverse populations is required before routine clinical implementation of this model
Turbulent thermal-magneto convection in a teardrop-shaped dimpled tube: An experimental and numerical study
No full textIn this study, the forced convection properties of teardrop-shaped dimpled fins, Fe 3 O 4 /H 2 O ferrofluid, and constant magnetic field parameters were investigated numerically and experimentally. The study consists of two parts. In the first part, a numerical simulation was conducted, incorporating all relevant parameters, and the results were analyzed. In the second part, the experimental setup was completed for the scenario that yields the highest performance evaluation criterion value, as determined from the numerical results. The Reynolds number (10000≤ Re ≤ 50000), the size of the teardrop-shaped dimple ( BTD , MTD and STD ), dimples distance (30≤ P ≤ 50), constant heat flux ( qʺ = 20 kW/m2), ferrofluid concentration ratio (0.0≤ φ vol. ≤2.0) and the constant magnetic field strength applied at x/D = 20 location (0 T ≤ B 0 ≤ 0.3 T) were studied experimentally and numerically. The findings showed that the DT9 case increased the thermal performance change by 36.18 % compared to the smooth tube. The highest heat transfer rate occurred in the magnetic field strength B 0 = 0.3 T. The magnetic field strength caused an improvement in heat transfer of 5.12 % and 7.32 % in the Nusselt number, respectively, in the numerical and experimental results. The highest PEC was obtained by using φ vol. = 2.0 % Fe3O4/H2O nanofluid in case DT9 ( STD , P = 50 mm) at Re = 10000 and B 0 = 0.3 T, with a contribution of 32.45 % compared to the smooth tube. The compound effect amounts of teardrop-shaped dimples, ferrofluid, and constant magnetic field were obtained numerically and experimentally as 55.41 % and 55.37 % in Nusselt number, while obtained as 29.15 % and 32.45 % in PEC , respectively, compared to a smooth tube, using H2O and the absence of a constant magnetic field
Bibliometric and systematic review of biostimulant research under drought stress
No full textDrought stress, a critical environmental factor impacting global crop productivity, is exacerbated by the challenges of climate change. Biostimulants (BS), substances that enhance plant resilience to abiotic stress without directly providing nutrients, have emerged as a promising solution for mitigating drought induced damage. However, the increasing volume and diversity of research in this area necessitate a systematic approach to evaluate its development. This advanced bibliometric and systematic review analyzes 499 publications from the Web of Science Core Collection published between 2015 and 2024. The review focuses on the role of BS in drought stress management and identifies key research trends, influential authors, major journals. Emerging topics include phytohormonal regulation, antioxidant defense, and microbial interactions. The results reveal a substantial increase in research output, reflecting a growing global interest in BS as an eco-friendly alternative to conventional fertilizers. The review highlights several primary mechanisms by which BS enhance drought tolerance., These mechanisms include the modulation of plant stress response pathways and antioxidant systems. Additionally, microbial-based BS play a role in improving soil health and nutrient uptake. Despite notable progress, several gaps remain. These include the need for standardized evaluation methods and deeper molecular insights into BS action. This review offers a comprehensive overview of the field and provides insights for future research directions. It emphasizes the potential of BS to contribute to a more holistic approach to sustainable agriculture under climate change
Evaluation of plasma microRNA expressions in children with metabolic dysfunction-associated steatotic liver disease
No full textAim: This study investigated the effects of plasma microRNA expression levels on the pathogenesis of steatohepatitis associated with metabolic dysfunction in children. Materials and Methods: Twenty-one obese children with MASLD, 23 obese children without MASLD, and 20 age-sex-matched healthy children were enrolled in the study. The plasma levels of five miRNAs (miRNA-21, miRNA-33a, miRNA-33b, miRNA-34a, and miRNA-122a), which are known to be associated with MASLD, were examined in all the subjects. Plasma miRNA levels were measured by real-time PCR in the children. The groups were compared with each other. Results: It was determined that significantly increased levels of miRNA-21 and miRNA-122a, but decreased miRNA-33b and miRNA-34a levels, were observed in both the obese group with MASLD and the obese group without MASLD relative to the control group. No significant differences in those miRNA levels were found between the obese group with MASLD and the obese group without MASLD. However, miRNA-21 and miRNA-122a levels were two-fold higher, and miRNA-33b and miRNA-34a levels were approximately two-fold lower in the obese group with MASLD than in the obese group without MASLD. On the other hand, there were no significant differences in miRNA-33a levels across the study groups. Discussion: Plasma miRNAs may be involved in the pathogenesis of MASLD in children. More comprehensive and functional research about the role of these molecules is needed in this regard
Functional food potential of white tea from east black sea region: targeting GREM1 expression and metabolic dysregulation in obesity
No full textObesity is a major global health concern, being associated with insulin resistance and multiple metabolic disorders. Gremlin 1 (GREM1), a bone morphogenetic protein (BMP) antagonist, is increasingly recognized as a key regulator of adipose tissue dysfunction and impaired thermogenesis in obesity. Orlistat, a lipase inhibitor that reduces dietary fat absorption, is one of the most commonly used pharmacological agents for obesity management. White tea has demonstrated antioxidant and anti-obesity properties in experimental models. The aim of this study was to evaluate the effects of white tea on metabolic parameters (HOMA-IR, BMP4, Gremlin1) and GREM1 expression in rats made obese by a high-fat diet (HFD). A total of 40 male Sprague-Dawley rats were randomized into five groups: a standard diet group (STD); a high-fat diet group (HFD); an HFD + orlistat group (ORL); an HFD + 50 mg/kg white tea group (WT50); and an HFD + 150 mg/kg white tea group (WT150). Obesity was induced by feeding the rats a 45% high-fat diet for 3 weeks. Serum insulin, glucose and HOMA-IR levels were measured. Levels of GREM1 and BMP4 in serum and retroperitoneal adipose tissue were assessed. White tea supplementation significantly reduced weight gain and HOMA-IR compared to the HFD group. GREM1 mRNA expression in visceral adipose tissue decreased markedly in the WT50 and WT150 groups (p = 0.002 and p = 0.017, respectively). Serum GREM1 levels were significantly lower in the white tea-treated groups than in the HFD group (p = 0.011). Tissue BMP4 levels were only significantly reduced in the WT50 group (p = 0.005), indicating a non-linear dose–response pattern. There was a negative correlation between serum BMP4 levels and weight gain (rho = −0.440, p = 0.015). White tea was associated with improvements in metabolic parameters in an HFD-induced obesity model. These observations suggest a potential association between white tea bioactives and adipose tissue-related molecular pathways implicated in obesity. Given the short intervention duration and the exploratory design of this animal study, the findings should be interpreted with caution