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Magnetic solid phase extraction of methiocarb pesticide from food samples prior to HPLC analysis with magnetic activated carbon cloth/zinc aluminate (magnetic ACC@ZnAl<sub>2</sub>O<sub>4</sub>) composite
No full text<p>Methiocarb is a carbamate pesticide and is widely used due to its short lifetime but is a health concern due to its toxicity. To address this challenge, a novel nano-sorbent (zinc aluminate hybrid doped onto a magnetic activated carbon cloth (magnetic ACC@ZnAl2O4)) was synthesized. The characterization of the composite was done using FTIR spectroscopy, SEM, XRD, and EDX. The synthesized composite was then employed for the efficient extraction of methiocarb from food samples. Under the optimum conditions of (pH: 7.0, vortex time: 0.5 min, adsorbent dose: 5 mg, initial volume of sample: 50 mL, volume of eluent: 1.0 mL), quantitative recovery values of methiocarb in food samples were obtained (80-114%). This method impresses with its exceptional sensitivity, achieving incredibly low detection (LOD: 20 mu g L-1) and quantification (LOQ: 67 mu g L-1) limits for methiocarb. Its efficiency is equally impressive, with high values of preconcentration factor (PF: 50) and enhancement factor (EF: 49.4), ensuring accurate and reliable analysis with a low value of relative standard deviation (RSD: 4.8%). The method's impressive selectivity, evident in its minimal interference from other pesticides, paves the way for reliable methiocarb analysis in food samples.</p>
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Sarcopenia Seems to Be Common in Older Patients With Restless Legs Syndrome
No full text<p>Background: Restless legs syndrome (RLS) is a disorder characterized by nocturnally exacerbating pain that leads to significant sleep disturbances. The hormonal and metabolic changes caused by sleep disruption may increase the incidence of muscle-related diseases like sarcopenia in older adults, which is defined by a progressive loss of muscle strength and mass. This study aimed to investigate the relationship between RLS and sarcopenia, which may affect each other through common pathophysiological pathways in older adults. Methods: This was a cross-sectional study including 109 patients with RLS and 220 without RLS who applied to the geriatric clinic. RLS was assessed using the Turkish version of the International Restless Legs Syndrome Study Group (IRLSSG). Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People-2 criteria. All the demographics, comorbid conditions, medications and findings of comprehensive geriatric assessments were recorded. The association between RLS and sarcopenia was examined by logistic regression. Results: The mean age was 75 +/- 7.4 and 73.8 +/- 7 years for the RLS and the control groups, respectively (p > 0.05) and the ratio of females was higher in the RLS group (69.7% vs. 57.9%) (p = 0.035). The frequencies of coronary artery disease (CAD), hypertension (HT) and peripheral artery disease (PAD) were significantly higher in RLS patients (p = 0.020, p = 0.047, p = 0.010, respectively), while the prevalence of anaemia was 41% and 25-OH Vitamin D levels (25[OH]D) were higher than in the control group (p < 0.001). The frequency of probable sarcopenia and sarcopenia was higher in patients with RLS than in controls (20% vs. 11%, p = 0.037 and 8% vs. 2.3%, p = 0.047, respectively). A significant association between RLS and an increased likelihood of probable sarcopenia, sarcopenia and slow gait speed (odds ratio [OR]: 2.621, 95% confidence interval [CI] [1.265, 5.431]; OR: 4.542, 95% CI [1.284, 16.071]; OR: 2.663, 95% CI [1.432, 4.951], respectively) was found after adjusting for factors such as gender, HT, CAD, PAD, serum 25(OH)D levels, anaemia, chronic kidney disease (CKD) and nutritional status. However, the significance of low muscle mass disappeared (p > 0.05). Conclusion: This study demonstrated that sarcopenia is prevalent among older patients with RLS, which seems to be associated with low muscle strength and slow gait speed. Given the negative health outcomes related to sarcopenia, interventions aimed at preventing its development could be significantly beneficial for patients with RLS in older adults as well.</p>
Assessment of climate changes for predicting water-energy-food-ecosystem nexus vulnerability in a semi-arid basin
No full text<p>The Water-Energy-Food-Ecosystem (WEFE) nexus highlights the interconnections between water, energy, food, and ecosystems. This study examines climate change's impact on precipitation and temperature in the semi-arid Sakarya Basin, assessing WEFE nexus vulnerability in the 21st century. Climate scenarios (RCP 4.5 and 8.5) from CCSM4 and MIROC5 were downscaled to 18-km grids for three future periods (2020-2030; 2055-2065; 2090-2100) using the Weather Research and Forecasting Model (WRF). The assessment integrates these downscaled data with a range of socio-economic and environmental indicators across seven subbasins. In the most arid, agricultural subbasin, a 22% reduction in precipitation and a 2.9 degrees C temperature rise are projected. The most populous subbasin may face a 30% precipitation decline and a 3 degrees C temperature increase. A subbasin, crucial for hydroelectric power, could see a 14% precipitation decrease and a 3 degrees C temperature rise. These subbasins are identified as the most vulnerable in terms of agricultural productivity, municipal water demand, and energy generation, highlighting significant WEFE nexus challenges. Additionally, the ecosystem sector is highly vulnerable when evaluated against environmental flow parameters. Insights from this study will guide strategies to enhance WEFE nexus resilience in the Sakarya Basin and similar regions under changing climates.</p>
Evidence for an aseismic gap between the Mw6.8 Puturge (Elazig) and 7.8 Pazarcik (Kahramanmaras,) earthquakes in the east Anatolian fault system, southeast Turkiye
No full text<p>This study examines the unruptured portion of the Puturge segment, the least-studied section of the East Anatolian Fault System (EAFS) in southeast Turkiye, focusing on the S,iro Valley to comprehensively understand the observed distribution in deformation. Despite the February 6, 2023 doublet earthquakes, the Puturge segment near the S,iro Valley remained relatively stable, though significant stress accumulation was detected at both ends. Fieldwork and subsequent morphometric and structural analyses confirmed notable tectonic activity in the area. Geomorphic indices were applied to assess tectonic activity, yielding an average index of relative tectonic activity (Iat) for all drainage basins, highlighting varying tectonic intensity levels across the S,iro Valley. Mountain front sinuosity (Smf) analysis indicated different uplift rates and tectonic forces along distinct fault segments. Additionally, Hypsometric Integral-Hypsometric Curve (HI-HC) index analysis pointed to rapid uplift processes, particularly in the eastern part of the fault-controlled basin, signaling active tectonic uplift and geomorphic rejuvenation. Normalized steepness index (ksn) and Chi (chi) values highlighted variations in erosion rate, providing insight into regional uplift patterns and knickpoint distributions. These findings align with the dominant transtensional tectonic regime in the area, as inferred from slip data inversions along the S,iro Valley. The region's fault geometry, oblique movement, and block rotations firmly support this interpretation. Comparisons of slip rates and ground deformation models revealed notable variations in fault behavior, suggesting ongoing energy accumulation, possibly linked to aseismic creep. The complex fault system behavior was underscored by the 2020 Sivrice earthquake and the 2023 doublet, which highlights the critical role of the Puturge segment in the dynamic evolution of the EAFS.</p>
Rotor pole and stator tooth shaping in FSPM machines for torque performance optimization
No full text<p>PurposeThis study aims to obtain the minimum torque ripple at the maximum average torque for Flux-switching permanent magnet (FSPM) machines.Design/methodology/approachThis paper is about torque performance optimization of the FSPM machines. To achieve that, finite element analysis and genetic algorithm (GA) are used. Five different designs are simulated, optimized and compared on their air gap flux density, back electromotive force, cogging torque, average torque, torque density and torque ripple.FindingsAfter the thousands of iterations, its proved that all proposed shaping techniques have potential for reducing torque ripple and cogging torque, with slightly reduced average torque. The best design is the joint stator and rotor shaping, Design V, which results in the lowest torque ripple and cogging torque. The techniques should be applicable to FSPMs with other stator slot/rotor pole number combinations.Originality/valueIn this paper, rotor pole shaping by notching, chamfering and generic shaping, stator tooth shaping and joint shaping techniques are investigated for 12 s/10p FSPM machines. Rotor and stator flanks are optimized separately and jointly, by using finite element analysis and GA for optimization to achieve maximum average torque and minimum torque ripple. Five different design is implemented and compared, respectively.</p>
Veb saytların hazırlanma texnologiyaları. Python / Django nümunəsində
No full text<p>İnformasiya texnologiyalarının sürətli inkişaf etdiyi dövrümüzdə veb tətbiqlərin hazırlanması müasir proqramçıların əsas fəaliyyət sahələrindən birinə çevrilmişdir. Veb texnologiyalar sadəcə statik səhifələrin hazırlanması ilə məhdudlaşmır, əksinə, dinamik, funksional, istifadəçi yönümlü və təhlükəsiz tətbiqlərin yaradılmasını tələb edir. Bu kitab, veb proqramlaşdırmanın məhz bu tələblərinə cavab verən bir mühit —<strong> </strong><strong>Python dili və Django mühiti</strong> üzərində qurulmuş veb tətbiqlərin hazırlanması texnologiyalarını sistemli şəkildə izah etmək məqsədilə hazırlanmışdır.</p>
<p>Kitabda müasir veb proqramlaşdırmanın əsas komponentləri — freymvörklər, server və kliyent texnologiyaları, verilənlər bazaları, şablon qurmaq üçün sistemləri izah olunmuş, nümunələrlə dəstəklənmiş və praktik tətbiqlərlə zənginləşdirilmişdir. Django mühiti seçilərək, oxucunun real tətbiqlərlə işləmə vərdişlərini inkişaf etdirməsinə və sıfırdan tam funksional veb saytlar hazırlamasına şərait yaradılır.</p>
<p>Əsər təkcə nəzəriyyəyə deyil, həm də əməli bacarıqların formalaşmasına yönəldilmişdir. Burada Python və Django-nun quraşdırılması, layihə strukturu, modellərin yaradılması, admin panelin idarə edilməsi, URL yönləndirmə, şablonların hazırlanması, formaların istifadə qaydaları izah olunmuşdur. </p>
<p>Bu kitab ali təhsil müəssisələrinin tələbələri, proqramlaşdırma sahəsində çalışan mütəxəssislər, müəllimlər və veb texnologiyalarla maraqlanan bütün oxucular üçün faydalı olacaqdır.</p>
Methane-fueled porous burner combustion in a domestic boiler: Experimental and numerical study
No full text<p>Using porous media in burner combustion systems helps reduce NOx values by providing more homogeneous flame distribution and lowering local maximum temperature values. Additionally, it ensures less noisy combustion at low flame speeds. However, manufacturing porous media materials is difficult, and experimental studies on these structures are time-consuming and costly. Therefore, examining the effects of burners with different porosity values on combustion is challenging. This study focuses on experimental and numerical investigations of methane-air mixture combustion using a porous burner made of metal fiber material. Emission values for NOx, O2, CO2, and CO components were obtained from experimental studies conducted at different methane gas flow rates (0.436 m3/h, 0.802 m3/h, 1.004 m3/h, and 2.487 m3/h) in a domestic boiler. Additionally, viscous and inertial resistance parameters necessary for the Porous Media Approach used in the numerical model were determined experimentally by analyzing the relationship between pressure drop and velocity in the porous burner. The numerical study of fluid flow and combustion models was carried out using the entire three-dimensional geometry of the boiler components, such as the manifold, burner, heat exchanger, and exhaust. The maximum deviations between the experimental and numerical values for NOx, O2, CO2, and CO were determined to be 4.32 %, 1.31 %, 2.65 %, and 14.46 %, respectively, for a gas flow rate of 2.487 m3/h.</p>
Effects of position of semi-circular body on melting of a novel B4C/ RT44HC PCM nanocomposite in a closed space
No full text<p>This study focuses on optimizing the thermal performance of a novel Boron Carbide (B4C) enhanced RT44HC phase change material (PCM) nanocomposite by analyzing the effects of different semi-circular partition placements within a closed cavity. The primary objective is to determine how the position of these adiabatic bodies influences the melting behavior, thermal conductivity, and energy storage capacity of the PCM. Through detailed computational modeling using the finite volume method and experimental validation, the research reveals that incorporating B4C nanoparticles significantly improves thermal performance, achieving up to a 69.65 % increase in thermal conductivity and a 19.68 % enhancement in energy storage capacity compared to pure PCM. The findings contribute to the field of advanced thermal energy storage and management by presenting a robust strategy for optimizing heat transfer in PCM systems, with potential applications in sustainable building design, electronic cooling, and energy-efficient technologies.</p>
Enhancement in the performance of a vanadium-manganese redox flow battery using electrospun carbon metal-based electrode catalysts
No full text<p>This study investigates the performance of both a vanadium/manganese redox flow battery (V/Mn RFB) and an all-vanadium redox flow battery (VRFB), employing carbon metal fabrics (CMFs) prepared through electrospinning followed by carbonization. Noteworthy advancements are observed in both systems upon coupling CMFs with thermally treated graphite felt (GF) electrodes. Nearly doubled peak power density and 50 % higher capacity utilization over 150 charge/discharge cycles at 75 mA cm-- 2 are achieved for the V/Mn RFB with the incorporation of CMFs alongside graphite felt as catalysts. The VRFB demonstrates notable enhancements too, achieving approximately 200 cycles at a current density of 80 mA cm-- 2 , with high efficiencies (85 %) and electrolyte utilization (79 %) when CMFs are used in combination with graphite felts. These advancements may facilitate pilot-scale testing and integration of the V/Mn RFB for the employment in the renewable energy storage sector and grid-balancing studies.</p>