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In this study, spinel NiFe2O4 nanoparticles were synthesized employing a one‐step flame spray pyrolysis technique and subjected to annealing at 500°C for 4 h. Thermal, structural, elemental, morphological, magnetic, and photoluminescence properties of the nanoparticles before and after annealing were evaluated using thermogravimetry–differential thermal analyzer, X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy, scanning electron microscopy, dynamic light scattering, vibrating sample magnetometry, and fluorescence spectrometer, respectively. Results revealed a pronounced increase in particle size from an average of 80 nm to approximately 140 nm postannealing. XRD verified the retention of the cubic spinel structure with enhanced crystallinity and grain enlargement post‐thermal treatment, without the emergence of additional phases. The photoluminescence analysis showed distinct blue and green emission bands, with excitation at about 364 nm leading to blue emission at 500 nm and green emission at 550 nm both as‐prepared and postannealing. Additionally, magnetic characterization revealed an improvement in saturation magnetization from 16.31 emu/g for the as‐prepared samples to 29.68 emu/g postannealing, underscoring the annealing process's positive impact on magnetic properties. These findings emphasize the potential of tailored NiFe2O4 nanoparticles for applications in magnetic data storage, targeted drug delivery, and bioimaging, driven by modifications in their magnetic and photoluminescence characteristics through thermal treatment. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiOx) has received a lot of attention as an inorganic hole transport material (HTM) in perovskite solar cells (PSCs) during the last decade, owing to its high hole mobility, chemical stability, good optical transparency, and suitable energy levels that align with the valance band of the perovskite absorber methylammonium lead iodide (MAPbI3). This study explores Li and Mg co‐doped NiOx thin films physically‐deposited from developed sputtering targets obtained through cold isostatic pressing and sintering. After sputtering, the structural, elemental, morphological, optical, and electrical properties of the layers are investigated by XRD, XPS, SEM, AFM, UV–vis spectrophotometer, and Hall‐effect; revealing that crystalline, homogeneous, and smooth films are obtained. In particular, improvements in mobility and conductivity values are observed with Li and Mg doping, which contribute to enhanced PSC performance when used as an HTM layer in the glass‐indium tin oxide (ITO)/NiOx‐based HTM/MAPbI3/phenyl butryic acid methyl ester (PCBM)/bathocuproine (BCP)/Ag architecture. The champion solar cell achieves PCE of 15.52%. In addition, the average values of all samples are boosted, JSC (from 13.21 to 15.60 mA cm−2) and FF (from 59.32% to 67.7%), relative to pristine HTM, resulting in a pronounced PCE increment of up to 30% with the HTM film sputtered by a single target of co‐doped material. [ABSTRACT FROM AUTHOR]

In this study, manganese ferrite (MnFe2O4) nanoparticles were produced through flame spray pyrolysis (FSP). To investigate the effects of heat treatment, the nanoparticles were annealed between 400 and 650°C for 4 h in air in a comparative manner. The structural, chemical, morphological, and magnetic properties of the nanoparticles were evaluated using X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), dynamic light scattering (DLS), and vibrating sample magnetometry (VSM), respectively. The XRD results showed that the nanoparticles synthesized by the FSP method exhibited the MnFe2O4 spinel ferrite structure. The annealing process led to the decomposition of MnFe2O4 into various phases. According to the morphological analysis, the as‐synthesized particles were hemispherical–cubic in shape and had an average particle size of less than 100 nm. In addition, the chemical bond structures of the nanoparticles were confirmed in detail by XPS elemental analysis. The highest saturation magnetization was recorded as 33.50 emu/g for the as‐produced nanoparticles. The saturation magnetization of the nanoparticles decreased with increasing annealing temperature, while coercivity increased. [ABSTRACT FROM AUTHOR]

The enhancement of battery performance becomes one of the crucial points of the current research. In this study, the effect of zinc (Zn), tin (Sn), and lead (Pb) electrodeposited on carbon fibers (CF), and pristine‐CF on the negative plates of the lead acid batteries are investigated instead of the traditionally used polypropylene (PP) fibers as additives. The morphological and structural properties of the samples were characterized by scanning electron microscopy (SEM) and X‐ray diffraction spectroscopy (XRD). The electrochemical performance of the 2 V/30 Ah enhanced flooded cells were prepared and tested. The 50 % depth of discharge (DoD) cycles were carried out. Constant charging processes were applied at 60 °C for 42 days for water consumption tests. Although the best cyclic performances were recorded from the cells with pristine‐CF and CF/Zn, due to enhanced water‐loss in those samples, acidity was increased. On the other hand, with the addition of CF/Sn and CF/Cu/Pb, gassing is reduced resulting in acid stratification during charge/discharge process leading to lower cycle performance, eventually. Overall, using CF or metal modified CF instead of PP fibers enhances the number of charge‐discharge cycle by at least 23 cycles. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to evaluate the effects of percutaneous mitral balloon valvuloplasty (PMBV) on short- and intermediate-term aortic stiffness in patients with mitral stenosis. Materials and Methods This prospective study included 56 patients with critical mitral stenosis in normal sinus rhythm (68% female; mean age: 42 ± 11 years) and 37 healthy controls. Aortic stiffness was measured using transthoracic echocardiography before PMBV, and 24-48 hours and 1 year post procedure. Results Aortic strain and distensibility were significantly higher in the patients with mitral stenosis, both after PMBV and 1 year post procedure, whereas the aortic stiffness index (ASI) was significantly lower. There was also a significant decrease in mitral mean gradient (MMG) and systolic pulmonary artery pressure (sPAP) after PMBV, based on echocardiography and catheterization. Mitral valve area (MVA) significantly increased after PMBV. There was a significant correlation between change in ∆MVA and ∆MMG and aortic elastic properties. There was a significantly negative correlation between the ∆MVA and ∆∆ aortic stiffness (r = −0.62, P < 0.001), and a significantly positive correlation between ∆MMG and ∆ASI (r = 0.60, P < 0.001). Conclusion Mitral valve stenosis was associated with impaired aortic stiffness and following PMBV, aortic stiffness decreased during both the acute period and the intermediate period. [ABSTRACT FROM AUTHOR]

Nd-14.2 at%Al and Nd-20.0 at%Ag eutectic alloys were containerlessly solidified in an 8 m drop tube. The droplets were undercooled during the free fall in about 1 s under reduced gravity condition in He atmosphere. The cooling rates at the solidification temperature were computed as a function of droplet size by making use of heat balance calculations. They were ranging between 40 × 103 and 0.8 × 103 K s−1 for droplets in size range of 100-900 μm diameters. Nusselt, Reynolds, and Prandtl numbers of the droplets were calculated. Microstructures of the alloys were analyzed and eutectic spacings were determined. Microhardnesses of the droplets with different sizes were measured to reveal a dependence on the cooling rates with which the droplets are solidified. [ABSTRACT FROM AUTHOR]

In this study, nanoscale photocatalyst TiO2 powders were synthesized via sol-gel and flame spray pyrolysis ( FSP). Phase structures and ratios were analyzed by X-ray diffractometer ( XRD). Size, specific surface area, and morphologies were determined using particle size analyzer, Brunauer- Emmett-Teller theory, and scanning electron microscope, respectively. Anatase phase with some rutile together was obtained in XRD analysis. The degradation rates of aqueous methylene blue ( MB) by TiO2 nanopowders were calculated using UV-vis spectrophotometer. It was found that MB decomposition was successfully achieved with significantly high efficiencies for both sol-gel and FSP-derived powders with small differences. [ABSTRACT FROM AUTHOR]

Aim The aim of our study was to evaluate atrial electromechanical delay ( AEMD) and left atrial mechanical functions ( LAMF) in the patients with secundum-type atrial septal defect ( ASD). Method We included 72 patients with secundum type ASD in the study group and 35 gender and age-matched healthy volunteers for the control group. Maximal, minimal, and presystolic LA volumes were measured by modified Simpson method and indexed to the body surface area ( BSA). Inter- AEMD, right and left intra- AEMD were measured from the lateral and septal mitral annulus and tricuspid annulus using tissue Doppler imaging ( TDI). Results The age, gender, systolic and diastolic blood pressure, heart rate ( HR), BSA, and body mass index ( BMI) parameters were not significantly different between the groups. Left atrial active and total emptying fractions and conduit volumes were significantly lower in the patients with ASD compared with the control group (P = 0.006, P = 0.001, and P = 0.032, respectively). Total emptying volume was increased in patients with ASD (P = 0.021). Passive emptying volume and fraction and active emptying volumes were not different significantly between the groups (P > 0.05). The left intraatrial, right intraatrial, and inter- AEMDs were significantly longer in the ASD group (P = 0.032, P = 0.013, and P = 0.003, respectively). Conclusion The left atrial reservoir and contractile pump functions are reduced; the left intraatrial, right intraatrial, and inter- AEMDs are increased in the patients with ASD. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the efficiency of transesophageal tissue Doppler echocardiography (TDE) in evaluation of the left ventricular functions. To this end, the data obtained by transoesophageal tissue Doppler echocardiography and by transthoracic tissue Doppler echocardiography were compared simultaneously. Methods: Nineteen consecutive patients (7 female and 12 male) underwent a clinically indicated study. In transthoracic (TTE) and transoesophageal (TEE) echocardiographic study, a Vingmed System Five Doppler echocardiographic unit (GE Vingmed) was used. For the assessment of the left ventricular function using transthoracic and transoesophageal TDE, the mitral annular peak systolic (S), early diastolic (E), late diastolic velocities (A), late to early velocity ratio (E/A), deceleration times (DT), left ventricular isovolumetric relaxation times (IVRT) were measured at the lateral, medial, anterior, and posterior corners at the mitral annulus by activating TDE mode in the transthoracic and transoesophageal apical four- and two-chamber view. Bland–Altman plots were used to compare the two measurement techniques. The differences between the groups were assessed by Mann–Whitney U test. All the data were expressed as mean ± SD. A P-value of <0.05 was considered significant. Results: There were no significant differences between two techniques in terms of blood pressure and heart rate. Two techniques were compared for the transthoracic and transoesophageal TDE parameters. Bland–Altman analysis showed comparable values for E, A, E/A, S, and mE/E, although the measurements of DT and IVRT were different. Conclusion: PW tissue Doppler echocardiographic approach during TEE may be suitable for assessment of the left ventricular function. [ABSTRACT FROM AUTHOR]

Background: This study was planned to assess whether strain rate (Sr) and strain (S) echocardiography is a useful method for functional assessment of the left atrial appendage (LAA). Material and Methods : Fifty-seven consecutive patients underwent a clinically indicated study. LAA late empty velocity (LAAEV) was calculated as a gold standard for left atrial appendage function. Real-time 2-dimensional color Doppler myocardial imaging data were recorded from the LAA at a high frame rate. Analysis was performed for LAA longitudinal strain rate and strain from midsegment of lateral wall of LAA. LAA strain determines regional lengthening expressed as a positive value or shortening expressed as a negative value. Peak systolic values were calculated from the extracted curve. Results : Spearman correlation test results showed a statistically significant positive correlation was between the S, Sr variables and LAAEV (LAAEV vs S; r = 0.886, P < 0.001; LAAEV vs Sr: r = 0.897, P < 0.001, respectively). Strain and strain rate values were also significantly lower in patients with spontaneous echocardiographic contrast when compared with those without (strain; 2.42 ± 0.98 vs 13.1 ± 5.9, P < 0.001 and strain rate: 0.97 ± 0.54 vs 3.34 ± 1.15, P < 0.001, respectively). In addition, LAA strain and strain rate values were significantly lower in the patients with LAA thrombus (strain; 2.15 ± 0.96 vs 8.35 ± 6.9, P < 0.001, strain rate; 0.79 ± 0.46 vs 2.30 ± 1.48, P < 0.001, respectively). Conclusion: S and Sr imaging can be considered a robust technique for the assessment of the LAA systolic deformation. [ABSTRACT FROM AUTHOR]

Background: Our goal in this study was to examine the changes in the left atrial functions over a period of 3 months by using left atrial volume measurements in patients with anterior myocardial infarction (MI). Methods and Results: Seventy-three patients with anterior MI who consulted our hospital in the first 12 hours starting from the onset of the chest pain and who exhibited ST elevation were enrolled in the study. The left atrial functions of the patients were evaluated by transthoracic echocardiography for a total number of four times; first at the time of the visit to the hospital, then in the first week, and then in the first and third months. Eight (10.95%) of the 73 patients included in the study died during the follow-up. The remaining 65 patients completed the 3-month study period. Of these 65 patients, primary percutaneous transluminal coronary angioplasty (PTCA) was performed for 24 (36.9%) patients and thrombolytic therapy was given to 13 (20%), whereas 28 (43.1%) patients were given only medical treatment. Left atrium (LA) maximum transverse diameter, LA maximum, minimum, and presystolic volume, LA active emptying volume and fraction were found to increase significantly in comparison to baseline detected for this parameter in the first and third months (P < 0.001). However, LA passive emptying volume and fraction was found to decrease significantly in comparison to baseline detected for this parameter in the first and third months (P < 0.001). Conclusions: An increase in the diameter, volume, and dimensions of LA during atrial remodeling was detected. LA passive emptying fraction was found to decrease, whereas atrial active emptying function was found to increase to compensate for this change. [ABSTRACT FROM AUTHOR]

This study was performed to determine whether melatonin could have a protective effect against myocardial injury (MI) induced by isoproterenol (ISO) in rats. Twenty-four rats were divided into three treatment groups: (1) control (n = 8): saline solution. (2) ISO (n = 8): ISO only. (3) melatonin + ISO (n = 8). Melatonin (10 mg/kg/day, i.p.) was administered 30 min before the initiation of ISO (150 mg/kg/day, s.c.). Drugs and saline were given at 14:00 hr for two consecutive days. At the end of the second day, blood samples were taken from the abdominal aorta shortly after the rats were anesthetized for the purpose of measuring cardiac troponins T (cTnT) and I (cTnI); hearts were removed, preserved and examined microscopically. Additionally, based on the histological changes in myocardial tissue, the rats were divided into three groups: no change, mild changes and moderate and/or marked changes. The mean cTnT and cTnI values were significantly increased in ISO group compared with control group [(1.29 ± 0.22 ng/mL versus 0.46 ± 0.07 ng/mL, P < 0.0001) and (0.56 ± 0.11 ng/mL versus 0.21 ± 0.01 ng/mL, P < 0.001)], respectively, and were significantly reduced in the ISO + melatonin group (0.65 ± 0.06 ng/mL for cTnT and 0.25 ± 0.01 ng/mL for cTnI) compared with the ISO only group (P < 0.01), respectively. cTnT and cTnI values were significantly increased in rats with moderate and/or marked cardiac changes compared with hearts where there were mild changes and no change (P < 0.05). ISO + melatonin group showed less histological changes than the ISO group (P < 0.01). In conclusion, this study revealed a protective effect of melatonin against ISO-induced MI in rats, and its potential clinical application in the treatment of MI. [ABSTRACT FROM AUTHOR]