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The investigation of the effect of K doping on the structural, magnetic, and magnetocaloric properties of La1.4-xKxCa1.6Mn2O7 (0.0 <= x <= 0.4) double perovskite manganite
No full textIn this study, the effect of potassium doping on the morphological, crystallographic, magnetic and magnetocaloric properties of La1.4Ca1.6Mn2O7 double perovskite produced by the sol-gel wet chemical method was investigated. XRD analysis reveals that all samples have different percentages of tetragonal I4/mmm space group (double perovskite) and orthorhombic Pnma (perovskite) space group with. All samples showed a ferromagnetic to paramagnetic transition and a systematic decrease in T-C values was observed from 250 K for x = 0.0 to 150 K for x = 0.4 sample due to the increased amount of K+ due to the coexistence of different ferromagnetic and antiferromagnetic interaction ratios in the samples. A decrease in the magnetic entropy change values was also observed with the decrease in the ferromagnetic double exchange interaction, due to the fact that the Mn4+ ions increasing with the K+ doping support the antiferromagnetic Mn4+-O2--Mn4+ super-exchange interactions. For the field change of 1 T, the maximum magnetic entropy change for the sample La1.4Ca1.6Mn2O7 was found to be 1.0 Jkg(-1) K-1 it decreased down to 0.68, 0.75 and 0.60 Jkg(-1) K-1 for La1.3K0.1Ca1.6Mn2O7, La1.2K0.2Ca1.6Mn2O7, La1.0K0.4Ca1.6Mn2O7, respectively. Experimental results indicate that the samples can be potential candidates for sub-room temperature magnetic cooling application
The Effects of the Activity of Making Jewelry From Beads on the Anxiety Levels of Children With Cancer: A Randomised Controlled Study
No full textBackground: Children hospitalized for cancer treatment are known to experience high levels of anxiety. This study aimed to examine the effects of making jewelry from beads on the state and trait anxiety levels of children with cancer. Methods: This parallel group, randomized controlled trial was conducted on 62 children aged 7-18 who were being treated for cancer. The children were selected using the random sampling method. The jewelry-making sessions with the children in the intervention group were held twice a week for four weeks. Data were analysed using the chi-square test, the Student's t-test, the independent samples t-test and linear regression. Results: The state anxiety levels of the children in the intervention group decreased both in the first week and the fourth week after making jewelry. The difference in the average post-test scores between the two groups was found to be significant (p < .05). The fourth week average trait anxiety score of the children in the intervention group decreased (M = 33.2) in comparison to the average score of the control group (M = 36.5). The difference between the two groups was found to be significant (p < .001). Discussion: This study found that the activity of making jewelry from beads was effective in reducing the state and trait anxiety levels of children with cancer
Stiffness requirements for wind girders in open-top cylindrical steel tanks
No full textAboveground cylindrical storage tanks are very thin shell structures which are prone to buckling when subjected to wind pressure. Both external and internal pressures are developed due to wind action, and the magnitudes of the pressures generally vary around the circumference. A wind girder is generally used in open top cylindrical tanks to increase their resistance against buckling. The wind girder must have adequate strength and stiffness in order to fulfill its function properly. Widely used design specifications provide recommendations for the design of the wind girder. Strength requirements are given in terms of stress resultants, while a minimum second moment of area is provided as a stiffness requirement. The recommendations for the stiffness requirement were developed by conducting Linear Elastic Bifurcation Analysis (LBA) of cylindrical shells subjected to uniform external pressure. This paper explores stiffness requirements for the wind girder in open top cylindrical steel tanks. The relationship between the buckling strength and the second moment of area of the wind girder was explored through a finite element parametric study. Tank shells with different radius-to thickness and height-to-diameter ratios and having different wind girder sizes were investigated by means of LBA. A buckling strength curve was developed based on the LBA results where the strengths can be predicted with 90% accuracy. In addition, a new second moment of area requirement was proposed. The parametric study was extended to investigate the behavior using Geometrically Nonlinear Analysis including Imperfections (GNIA). The same tank geometries were studied using GNIA and considering different imperfection amplitudes. A buckling strength curve, which takes into account imperfection amplitudes, was developed to be used in design
Could Peritoneal Dialysis be an Option for the Treatment of Congestive Heart Failure?
No full textbjective: Heart failure is a progressive and fatal disease even with appropriate treatment. Hypervolemia is a major cause of mortality and hospital admissions in these patients. Peritoneal dialysis has been successfully used for volume control in congestive heart failure patients with diuretic resistance in recent years. The present study aims to assess the effects of peritoneal dialysis on refractory heart failure. Methods: The 2-year follow-up data of 12 heart failure patients with reduced ejection fraction who had undergone peritoneal dialysis at our center between 2014 and 2019 were retrospectively analyzed in 3-month periods. The effects of peritoneal dialysis on functional status, echocardiography, physical and biochemical parameters, hospital admission, and mortality rates were assessed. Results: Functional capacity improved significantly (P = .005). When the sixth month was reached, no patient remained in the New York Heart Association class 4. A significant improvement was observed in mean arterial pressure (75.3 ± 17 vs. 91.3 ± 16.6; P = .005). There was an improvement in congestive symptoms (dyspnea, pleural effusion, and pretibial edema; P = .037; P = .0002; P = .005, respectively). Although statistical significance could not be reached, ejection fraction on echocardiography was found to increase (28.7% ± 12% vs. 37% ± 12%; P = .113). Despite statistical significance was not reached, there was a trend for an increase in hematocrit, serum albumin, and sodium levels and a decrease in uric acid level. The 1-year and 2-year mortality rates were 41.7% and 58.3%, respectively. Conclusion: In heart failure patients with reduced ejection fraction with diuretic resistance, peritoneal dialysis improves congestive symptoms, improves functional capacity, and offers a treatment option in addition to pharmacological therapy
Investigation of Some Bioactivities and Odor Components of Jasminum officinale Linn. (Oleaceae): A Valuable Tool for Cosmetic Product Design
No full textIn this study, researches were carried out on the protease enzyme activity of Jasminum officinale Linn. flower which grows naturally in Muğla and its surroundings. In addition, fragrance components in the content of jasmine flower were determined. It was aimed to be used in perfume making based on the harmony of white jasmine flower with other flowers and the concept of note. Protease enzyme was purified from J. officinale flower using TPP (Three Phase Partitioning) method. Optimal pH and optimal temperature for the enzyme, Km and Vmax values for casein, azokazaein, gelatin, hemoglobin, and azoalbumin substrates were determined. SDS-PAGE was used to check the purity of the protease enzyme purified from the J. officinale. The molecular weight of the enzyme was calculated as 21.386 kDa using gel filtration chromatography. The phenolic content was also determined. It has been determined that the content of jasmine flower can be used in perfume design which is the most prestigious product of the cosmetic industry
Концентрація розчинного Fas-ліганду в сироватці та потокоопосередкована вазодилатація у пацієнтів, які лікуються методом перитонеального діалізу
No full textFlow-mediated vasodilation (FMD) has been demonstrated to be a useful, non-invasive tool for the detection ofendothelialdysfunction in atherosclerotic cardiovascular disease, the leading cause of mortality in end-stage kidney disease. The Fas/Fas ligand system of apoptosis resulting from activation of the caspase cascade- contributes to the pathophysiology of atherosclerosis. This ‘apoptotic’ system plays a central role in immune homeostasis. Vascular endothelial cells and inflammatory cells are the main resources of the Fas ligand. In this study, we aimed to investigate the role of soluble Fas ligand (sFasL) as a marker of FMD in peritoneal dialysis (PD) patients. Methods. A total of 43 patients undergoing maintenance PD and 40 healthy donors were enrolled in this cross-sectional observational study. Demographics, anthropometric measurements and clinical examinations were obtained. Endothelial function was evaluated by FMD of the brachial artery with high-resolution ultrasonography. Serum sFasL concentrations were measured with an enzyme-linked immunosorbent assay kit. Results. The enrolled partisipants were devited on 2 groups: PD patients who had been treated at least 12 weeks (group 1; mean age 41±14 years, M/F: 22/21) and gender matched 40 healthy controls (group 2; mean age 50±12 years, M/F: 19/20). The forearm FMD and serum sFasL levels were significantly lower in PD patients (3.95±2.01 vs 8.83 ± 6.17; p<0.001 and 54 ± 24 vs 73 ± 30; p=0.001). Forearm FMD was correlated with sFasL (r=0.289; p=0.008), age, BMI and uric acid (r= 0,32; p=0.003, respectively), hemoglobin (r= 0,293; p=0.007), calcium (r= 0,26; p=0.016), phosphate (r=- 0,250; p=0.023), magnesium (r= 0,255; p=0.020), 24 h SBP (r=- 0,257; p=0.019), creatinine and iPTH (r=- 0.50 and r=- 0,45; p<0.001, respectively). After adjustment for age, the stepwise multivariate analysis showed sFasL was independently associated to FMD (β: 0.180; p=0.03, CI: 0.078-0.314). vs 73 ± 30; p=0.001). Conclusions. sFasL may be used as a simple screening marker for endothelial dysfunction in PD patients
A Study on the Characterization of Citrus Pollen Grains
No full textCitrus is one of the most important economic fruit species worldwide. Pollen properties are one of the hereditary characteristics used in the identification of plants. In this study carried out in different Citrus genera and species, pollen size and morphology were investigated by scanning electron microscope (SEM). According to this, pollen shape is divided into two groups as oblate and suboblate. Colpi and pore are located on the pollen surface. The statistical difference occurred among the ten Citrus genotypes in terms of mean pollen length, width, length/width ratio and measurements of surface structures. Lemon varieties have the longest pollen, in general. Poncirus trifoliate was separated from the others by taking place alone
The Adaptation of Body Image Flexibility Scale Into Turkish
No full textBeden İmgesi Esnekliği, beden imgesi ile ilgili olumsuz düşüncelerden gerçek anlamda ayrışmak, değerlere adanmış bir şekilde eyleme geçmek ve yaşantısal kaçınma olmaksızın arzulanan davranışlarda bulunmak açısından psikolojik esnekliğin tüm temel özelliklerini işin içine dâhil eder. Beden İmgesi Esnekliği Ölçeği ise 12 maddeden oluşan ve beden imgesine yönelik kabul ve kararlılık düzeyini ölçümlemeyi amaçlayan bir ölçme aracıdır. Bu çalışmanın amacı, Beden İmgesi Esnekliği Ölçeğinin Türkçeye uyarlanmasıdır. Bu çalışma bir devlet üniversitesinde öğrenim gören 300 üniversite öğrencisi ile yapılmıştır. Çalışmanın amacı doğrultusunda ölçeğin geçerlik ve güvenirlik çalışmaları yapılmıştır. Öncelikle ölçeğin yapı geçerliliğini belirlemek için doğrulayıcı faktör analizi gerçekleştirilmiştir. Faktör analizine göre uyum istatistikleri, orijinal formun faktör yapısının doğrulandığını göstermiştir. İkinci olarak ölçeğin iç tutarlık katsayısı incelenmiştir ve Cronbach alfa katsayısı yüksek bulunmuştur. Toplam puan için test-tekrar test korelasyon katsayısı ise anlamlıdır. Sonuç olarak, Beden İmgesi Esnekliği Ölçeğinin Türkçe versiyonu Türk örneklemi için iyi geçerli ve güvenilir bir ölçektir. Elde edilen bulgular literatür ışığında tartışılmıştır.Body Image Flexibility incorporates all the essential features of psychological flexibility in terms of truly dissociating from negative thoughts about body image, acting with dedication to values, and engaging in desirable behaviors without experiential avoidance. The Body Image Flexibility Scale is a measurement tool that consists of 12 items and aims to measure the level of acceptance and stability towards body image. The purpose of this study is to adapt the Body Image Flexibility Scale to Turkish. This study was conducted with 300 university students from a university in Turkey. In line with the purpose of the study, validity and reliability studies of the scale were conducted. First, confirmatory factor analysis was designed to determine the construct validity of the Body Image Flexibility Scale. According to the factor analysis, the fit statistics showed that the factor structure of the original form was confirmed. Secondly, the internal consistency of the scale was tested and the Cronbach alpha coefficient was found to be high. Testretest correlation coefficient for the total score is significant. In conclusion, the Turkish version of the Body Image Elasticity Scale is a well valid and reliable scale for the Turkish sample. The findings discussed in the light of the literature
Temperature Dependent Current Transport Mechanism of Photopolymer Based Al/NOA60/p-Si MPS Device
No full textA photopolymer based Al/Norland Optical Adhesive 60 (NOA60)/p-Si MPS (metal-polymer-semiconductor) device was fabricated by a combination of vacuum evaporation and smear technique. The current transport properties of the device were investigated by using the forward bias current-voltage (I-V) characteristic in the temperature range of 80-300 K. The cross-sectional structure of polymer/semiconductor was revealed by the scanning electron microscope (SEM) image and it was seen that the NOA60 photopolymer was tidily coated on the p-Si surface. According to the I-V measurements at room temperature, the MPS device exhibits a good rectification ratio of 8140 at +/- 1 V. The temperature-dependent I-V measurements (I-V-T) were analyzed based on the thermionic emission (TE) theory and an abnormal increase in zero-bias barrier height (BH) and a decrease in ideality factor (n) was observed with increasing temperature. Additionally, two different linear regions with distinct values from the theoretical value of the Richardson constant (A*) were observed in the conventional Richardson plot. Such deviations from the ideal TE theory have been attributed to the effect of BH inhomogeneities. Gaussian distribution (GD) of the BH model has applied the I-V-T results and the double GD BH with mean values of 0.75 +/- 0.08 eV (80-140 K) and 1.02 +/- 0.11 eV (140-300 K) were calculated. Moreover, the A* value of 31.4 A/cm(2)K(2) was calculated close to the known value of p-Si from the modified Richardson plot. Thus, it has been concluded that the current transport of the Al/NOA60/p-Si MPS device can be explained by TE with a double GD BH model for a wide temperature region
The organizational power applied by school principals and its effect on teachers’ perception of power distance
No full textThe aim of this research is to examine the relationship between the power types used by school principals and the power distance perceptions of teachers. The population is composed of the teachers in Mugla (Turkey) and Tamale (Ghana). The sample is made up of 384 teachers from Mugla and 407 teachers from Tamale. The data used in this research were collected using Power Type Scale and Power Distance Scale, both of which were developed in schools. In the analysis of the data, descriptive statistics were used in determining teachers' views of the power types used by school principals and the teachers' power distance perceptions. T-test was used in determining the differences in opinions and perceptions regarding the power types and power distance according to the demographic variables considered in this study. In the statistical analysis made; 0.5 was chosen as the significant value. According to the findings of the research, Mugla and Tamale principals exhibited the same order of preference in the power types they employ. Mugla principals and Tamale principals used reward power and legitimate power respectively at statistically significant levels. Regarding power distance, Tamale teachers' perceptions in all the dimensions of power distance were higher than Mugla teachers' perceptions at statistically significant levels. In both Mugla and Tamale samples, power types used by principals were found to be very good predictors of teachers' power distance perceptions