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How does land consolidation in redesigned agricultural enterprises affect CO2 emissions?
No full textGreenhouse gases trap heat, contributing to global warming. Tractors, essential for modern agriculture, emit CO2 due to fossil fuel consumption. Reducing these emissions is crucial for environmental sustainability. Land consolidation, which merges small and fragmented plots into larger, more efficient farms, can optimize tractor use and lower fuel consumption. This study examined how farm size, number of plots, aspect ratio and distances affect CO2 emissions. Scenarios were created and grouped for all parameters. The results showed that increasing the number of plots and plot distances in small farms led to higher emissions per unit area. High emissions were not observed in medium and large farm size scenarios. The study concluded that planning small farm plots as close as one piece and limiting medium and large farms to a maximum of 4-5 plots significantly reduced emissions. Effective land consolidation planning can significantly reduce CO2 emissions from tractor use in agriculture
Intestinal endometriosis amongst other extra-pelvic endometriosis foci presenting as acute/subacute bowel obstruction in women of reproductive age: A retrospective case series study
No full textBackground This study aimed to investigate the prevalence and clinicopathological correlates of intestinal endometriosis, amongst other extra-pelvic endometriosis foci, presenting as bowel obstruction in general surgery practice. Methods A total of 23 female patients (mean +/- SD age: 34.9 +/- 6.5 years) who underwent abdominal surgery for acute bowel obstruction and received histopathological diagnosis of endometriosis were included in this retrospective case-series study. Data on patient characteristics, obstetric history, preoperative laboratory and imaging findings, preoperative provisional diagnosis, type of surgical intervention and the pathological diagnosis, and postoperative outcomes were recorded. Results Definitive diagnoses on histopathological work-up involved intestinal endometriosis (52.2%), scar endometriosis (26.0%), ovarian endometriosis (13.0%) and inguinal endometriosis (8.7%). Postoperative complication, reoperation and recurrence rates were 8.7%, 8.7%, and 13.0%, respectively. Intestinal endometriosis, when compared to other extra-pelvic endometriosis foci (scar and inguinal), was associated with significantly higher preoperative platelet counts (332.0(284.0-528.0)vs. 239.0(223.0-370.0) 103/mu L, p = 0.010), lower albumin levels (4.0(2.7-4.7) vs. 4.5(4.2-4.9) g/dL, p = 0.029), higher rates of preoperative CT utilization (91.7% vs. 0.0%, p < 0.001) and emergent surgery (83.3% vs. 0.0%, p = 0.001) and longer LOS (median 4.5 (1.0-26.0) vs. 1.0(1.0-1.0) days, p = 0.001) along with a non-significant tendency for higher postoperative complication (16.7% vs. 0.0%) and ICU stay (25.0% vs. 0.0%) rates. Conclusion Our findings revealed intestinal endometriosis, predominantly in the terminal ileum/appendix, was the most common extra-pelvic cause of acute bowel obstruction. The scar endometriosis, inguinal endometriosis and ovarian endometriosis appeared to be other potential but less prevalent aetiologies in this setting
Effects of different sowing times and harvesting stages on dry matter yield, quality, and mineral content of teff (<i>eragrostis teff</i> [zucc.] trotter)
No full textThis study aimed to identify the effects of different sowing times and harvesting stages on the dry matter yield, quality, and mineral content of teff (Eragrostis teff [Zucc.] Trotter). The study was conducted in 2021 and 2022 using a randomized block-split plot design with three replications. According to the two-year averages, plant height increased on the 1 June sowing time compared to 15 May, and there was more dry matter yield (4962.94 kg ha-1) and crude protein yield (717.48 kg ha-1) per unit area. Additionally, the crude protein content of the teff (156.30 g kg-1) increased, whereas the NDF content (652.38 g kg-1) decreased in the 1 June sowing time. Dry matter accumulation increased depending on the progress of the plant development periods, and, as a result, the late heading stage yielded the highest dry matter (5610.00 kg ha-1) and crude protein (615.90 kg ha-1). The crude protein content reached the highest level in the early heading stage, and the crude protein yield peaked at the highest level in the late heading stage since the yield per unit area was higher. While sowing times changed the Mg and Zn contents of teff, the extended harvesting stages resulted in significant variations in the P, K, Zn, Fe, Cu, and Na contents of teff grass. The highest identified P, K, Zn, Fe, and Na contents were in the booting stage, whereas the highest Cu content was in the early heading stage. The amount of various mineral compounds was higher in the early development periods; however, they were still sufficient to meet the needs of sheep and cattle throughout the early and late heading stages. Based on the study findings regarding high yield and quality, it is reasonable to recommend sowing teff grass in June and harvesting in the early heading stage under Mediterranean climatic conditions
Atmospheric pressure plasma surface treatment for structural adhesive bonding in automotive body manufacturing: A parametric study
No full textThis study investigates the optimization of structural adhesives used in automotive body manufacturing processes via Thermal Atmospheric Pressure Plasma (TAPP) and Cold Atmospheric Plasma (CAP) surface treatments. Surface preparation of sheet metal parts using plasma before the adhesive joining process represents an innovative approach not yet utilized in automotive body production, and this work seeks to fill a gap in the existing literature. Test samples were prepared to compare the effects of curing temperature and time, as well as of TAPP versus CAP surface preparation, on bond strength. Using a Taguchi experimental design, we systematically varied five parameters: adhesive curing time, curing temperature, plasma type (TAPP or CAP), plasma-sample distance, and number of plasma passes. Tensile tests on the resulting specimens quantified bond strength, and regression analysis of those results identified the optimal processing conditions. The findings offer valuable insights into how TAPP and CAP treatments affect the adhesive joining of automotive sheet metals and establish the optimum parameters for each method
The impact of microscopic extrathyroidal extension on the prognosis of medullary thyroid carcinoma: A multicenter cohort study
No full textPurpose: Despite several factors are associated with worse disease-free survival (DFS) and prognosis in medullary thyroid carcinoma (MTC) patients, the effect of microscopic extrathyroidal extension (mETE) on the prognosis and DFS is not well understood. This study aims to evaluate the impact of mETE on DFS and prognosis in patients with MTC. Methods: This multicenter study included 208 patients with MTC (17.8% with hereditary disease). Patients with mETE were compared to those without mETE in terms of clinical and histopathological variables. Results: Among the 208 patients, 16.3% (n = 34) had mETE on histopathological analysis. Patients with mETE were more likely to have larger tumors, higher serum calcitonin (CTN) levels before and after surgery, increased rates of neck lymph node (LN) and distant metastasis, multifocal disease, and advanced disease stage. Kaplan–Meier analysis showed a significantly lower DFS in patients with mETE than those without mETE (14.7% vs. 71.3%, log-rank p < 0.001). However, mETE was not an independent contributing factor for persistent/recurrent disease, whereas neck LN involvement was the strongest independent contributing factor for persistent/recurrent disease (HR: 1.1; 95% CI 0.4–1.8, p = 0.76 and HR: 9.6; 95% CI 1.21–76.9, p = 0.03, respectively). Conclusion: mETE in patients with MTC is associated with a lower DFS, larger tumor sizes, a higher likelihood of neck LN and distant metastasis, advanced stage, higher serum CTN levels, multifocality, and persistent/recurrent disease. However, mETE was not an independent predictor of persistent/recurrent disease. Further studies with a larger number of patients with mETE could further clarify the impact of mETE on the prognosis of MTC
New accurate deep learning model for diabetic retinopathy detection utilizing sequential pre-processing and transfer learning
No full textThis study considers the detection of Diabetic Retinopathy (DR) using deep learning. DR affects 80% of diabetic patients worldwide and is the second leading cause of blindness. Many studies have shown that early diagnosis and treatment are critical to prevent disease progression. The contribution of this study is the development of an accurate DR detection algorithm and corresponding model, where hemorrhages were brought to a more apparent form by an efficient processing pipeline. To handle limited DR data resources and to make the visibility of bleeding in the eye more apparent, we have developed an efficient deep learning model by combining data augmentation, pre-processing, transfer learning, and adaptation of a compatible CNN. The employed dataset comprises fundus images of individuals, which are categorized into five stages of DR. For evaluation, comprehensive ablation studies are conducted on the model. Next, the developed model is evaluated against state-of-theart algorithms and demonstrates promising results in key metrics. Particularly, the model yields 96.95% accuracy and introduces a false negative rate below 1%. Efficient metrics of the study minimize the risk of missed diagnoses and reduce the likelihood of severe vision loss in diabetic patients. Therefore, our model has the potential to contribute to clinical patient care
Concentrations, temporal variations, human exposures and source identifications of pcdd/fs from an urban site employing passive air samplers in Bursa, Türkiye
No full textPolychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) are toxic, long-lasting pollutants that accumulate in human fat tissue, posing significant health risks. The obtained data were evaluated based on congener profiles and levels, possible sources, seasonal concentration changes, health risks and atmospheric transport. This study investigated atmospheric PCDD/F levels in an urban site from June 2022 to June 2023 using three passive air samplers (PASs) in Bursa, T & uuml;rkiye. Monthly samples were taken using three passive air samplers. The findings demonstrated the utility of PAS as a cost-effective and reliable monitoring device. Seasonal average concentrations were 324.66 f 51.87 fg/m3 in spring, 234.79 f 57.57 fg/m3 in summer, 363.07 f 77.99 fg/m3 in fall and 479.88 f 73.20 fg/m3 in winter. The yearly mean concentration value was 341.50 f 108.27 fg/m3. The measured concentrations in this study corresponded closely to those reported for regions with similar characteristics. The most dominant congeners observed during the sampling period were OCDD, OCDF, 1,2,3,4,6,7,8-HpCDF and 1,2,3,4,6,7,8-HpCDD. The measured concentrations indicated no threatening situation in the risk evaluation. Pollutant transport was determined to be mostly local, suggesting limited long-range movement after employing the Clausius-Clapeyron equation. Principal component analysis (PCA) identified vehicle emissions, residential heating and industrial combustion as key sources of PCDD/Fs. Seasonal variation and source analysis emphasized the effect of human activities and meteorological patterns. This study contributes to understanding urban air pollution and supports future efforts to manage PCDD/F emissions in similar regions
Performance of x and inverted v bracing systems in controlling progressive collapse of reinforced concrete buildings
No full textProgressive collapse can lead to partial or total failure of structures under extreme events such as explosions or earthquakes. While brace systems effectively enhance lateral stiffness, their use in reinforced concrete (RC) buildings is limited due to detailing challenges at connection points. This study evaluates the influence of X and inverted V bracing systems on the progressive collapse behavior of RC buildings and investigates the effectiveness of optimally placed X-bracing configurations under multiple column removal scenarios. Three groups of 9-, 12-, and 15-story RC buildings, designed per the Turkish Building Earthquake Code (TBEC2018), were modeled using the Applied Element Method (AEM) in the ELS software. The first group included unbraced reference models. The second group comprised 54 fully braced models using X and inverted V configurations, subjected to three distinct column removal scenarios. The third group included 27 models with X bracing placed only in selected bays to determine optimal configurations for collapse prevention. Nonlinear dynamic analysis of 84 models revealed that both the reference buildings and those with inverted V bracing experienced progressive collapse, with maximum top displacements reaching over 65 cm. In contrast, fully braced X systems effectively prevented collapse, reducing displacements to below 10 cm. Optimized Xbracing layouts, applied to only 30-50 % of the bays, achieved comparable performance while reducing material usage and detailing complexity. This study demonstrates the superiority of RC X-bracing in enhancing progressive collapse resistance and provides practical recommendations for optimal placement in reinforced concrete (RC) buildings
The polymer composite particles for adsorption and photocatalytic degradation of reactive black 5: Equilibrium, kinetics, thermodynamic, and isotherms studies
No full textFe3O4-poly(EGDMA-VPBA)-TiO2 particles with magnetic and photocatalytic properties were prepared using suspension polymerization with 4-vinylphenylboronic acid and ethylene glycol dimethacrylate for the adsorption and photocatalytic color removal of Reactive Black 5 (RB5) from aqueous solutions. Various analyses were made for the characterization processes of synthesized Fe3O4-poly(EGDMA-VPBA)-TiO2. These polymer composite particles were tested for both adsorption and photocatalytic color removal of RB5. In adsorption studies, the effects of solution pH, initial color concentration, adsorbent amount, contact time, and solution temperature on the adsorption capacity of composite particles were studied. Maximum removal in RB5 adsorption was achieved at pH 3. Adsorption removal increased with increasing temperature and decreased with increasing amount of adsorbent. The experimental adsorption data were found to be consistent with the Langmuir isotherm model, and the adsorption kinetics were determined to follow the pseudo-second-order equation mechanism. Thermodynamic parameters of RB5 adsorption were calculated. For the photocatalytic removal of the remaining colors in the aqueous solution without being adsorbed, the parameters of photocatalyst amount, color concentration, and time were examined, and the color removal kinetics were clarified. The photocatalytic effect for Fe3O4-poly(EGDMA-VPBA)-TiO2 was observed at low RB5 concentrations and high photocatalyst content. In addition, decolorization kinetics were found to be coherent with the Langmuir-Hinshelwood (L-H) model
Extremal values of second zagreb index of unicyclic graphs having maximum cycle length: Two new algorithms
No full textIt is well-known that the necessary and sufficient condition for a connected graph to be unicyclic is that its omega invariant, a recently introduced graph invariant useful in combinatorial and topological calculations, is zero. This condition could be stated as the condition that the order and the size of the graph are equal. Using a recent result saying that the length of the unique cycle could be any integer between 1 and n - a1 where a1 is the number of pendant vertices in the graph, two explicit labeling algorithms are provided that attain these extremal values of the first and second Zagreb indices by means of an application of the well-known rearrangement inequality. When the cycle has the maximum length, we obtain the situation where all the pendant vertices are adjacent to the support vertices, the neighbors of the pendant vertices, which are placed only on the unique cycle. This makes it easy to calculate the second Zagreb index, as the contribution of the pendant edges to such indices is fixed, implying that we can only calculate these indices for the edges on the cycle