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The biological activity and phenolic content of endemic Astragalus baibutensis
No full textAstragalus baibutensis, is a plant endemic to Turkey, belonging to Fabaceae family, that is used as a folk medicine and food in this country. The purpose of this study is to find out the biological activities such as antioxidant, antimicrobial, enzyme inhibitory and DNA protective activity and also analyse the phenolic contents of the plant. To determine of antioxidant activity ABTS and DPPH assays were performed. Disc diffusion and microdilution methods were used to evaluate the antimicrobial activity. Additionally, enzyme inhibitory activities such as α-amylase, α-glucosidase, and tyrosinase were determined by using spectrophotometric methods. DNA protective activity was detected using pUC19 Plazmid DNA. The antiproliferative effect on SKOV-3 human ovarian cancer cells was examined by WST-8 assay. In addition, the phenolic contents were analysed by using HPLC. The biological activity of ethyl acetate extract of the root was found to be higher than those of other extracts. This extract had the highest amount of apigenin as phenolic compound. On the other hand, extracts showed moderate inhibition against the tested microorganism and antiproliferative properties in a concentration-dependent manner toward ovarian cancer cells. According to the results, Astragalus baibutensis has the potential for pharmaceutical and food additive usage. © 2025 Societá Botanica Italiana
What is the relationship between fairness and trust in terms of tax compliance?
No full textTwo frequently researched factors in the tax compliance literature are perceptions of fairness and trust. Nevertheless, what is known about the relationship between the two variables is limited. Different findings in the literature have encouraged further research. This study aims to examine the relationship between fairness and trust in tax compliance and the role of these variables with multivariate statistical tests. In this direction, survey data were collected from 540 self-employed taxpayers in Istanbul/Turkey. As a result of the multivariate statistical tests carried out by dividing the data in two, the following conclusions were reached: (1) in line with the findings in the literature, perceptions of tax fairness and trust in tax authorities are essential determinants of tax compliance intention; (2) tax fairness positively affects trust in authorities and trust in authorities positively affects tax fairness; (3) both the mediating and moderating role of trust in tax authorities in the relationship between perceptions of tax fairness and tax compliance intention are confirmed; and (4) although there is a mediating effect of perceptions of tax fairness in the relationship between trust in tax authorities and tax compliance intention, the existence of a moderating effect could not be detected. © AESP 2025
Effectiveness of Psychosocial Interventions in Alcohol and Substance Use Disorders: A Meta-Analysis Study
No full textAlcohol and substance use disorders (ASUD), are increasing worldwide, and these psychiatric disorders are difficult to treat. The search for new treatments for these disorders continues. Psychosocial interventions (PI) are among them, and it is important to evaluate their effectiveness. This study aimed to assess the effectiveness of PI applied to individuals with ASUD. This meta-analysis was conducted by searching PubMed, Web of Science, EBSCOhost, Google Scholar, and YOK Thesis Center databases without year restrictions between October and December 2023. After reviewing the studies, 18 research articles were included in the analysis. The meta-analysis revealed that PI applied to individuals with ASUD were effective in reducing depression (SMD: -0.753, 95% CI: -1.215 to -2.91; I2 = 94.515; p < 0.05) and enhancing self-efficacy (SMD: 0.709, 95% CI: 0.096-1.321; I2 = 93.34; p < 0.05). However, these interventions were not found to be effective in improving self-esteem (SMD: 0.655, 95% CI: -1.641 to 0.331).3998273
The effect of high B4C ratio on the improvement of mechanical properties and wear resistance of Al2024/B4C composites fabricated by mechanical milling-assisted hot pressing
No full textIn this study, the effects of 0 wt% (C0), 10 wt% (C1), 20 wt% (C2) and 40 wt% (C3) B4C content on the microstructure, mechanical properties and dry wear properties of Al2024/B4C composites were investigated. In order to prepare Al2024 matrix composites with different B4C particle contents, mechanical milling (MM) and hot pressing (HP) were employed as powder metallurgy methods. It was found that the θ (CuAl2) phase content in the microstructure of Al2024/B4C compact materials increased with increasing B4C particle reinforcement, reaching its highest value at 40 wt% B4C (C3) reinforcement ratio. As the B4C particle reinforcement content increased, the hardness values of the composite samples increased. Flexural strength values were 445.30 MPa, 495.20 MPa, 277.59 MPa, and 129.37 MPa for samples coded C0, C1, C2, and C3, respectively. It was found that the C0 sample without particle reinforcement exhibited more than 10 times the volume loss of the C3 sample with the highest particle reinforcement at 450 m sliding distance. The SEM examination of the friction surfaces of the Al2024/B4C composite samples showed that the worn surfaces were composed of delamination, adhesion and smearing layers. © 202
A quantitative analysis on the effect of crystal parameters on full energy peak efficiency of a coaxial high purity Germanium detector for the energy range 50 keV-2.5 MeV
No full textHigh Purity Germanium (HPGe) detectors are essential instruments in gamma-ray spectrometry, offering high sensitivity and exceptional energy resolution. The full-energy-peak (FEP) efficiency is a critical parameter that influences the accuracy of activity concentration measurements of radionuclides. This study examines the FEP efficiency of a coaxial HPGe detector, focusing on variations in crystal length, crystal radius, and crystal hole dimensions. For varying crystal lengths, the efficiency values show negligible differences at low energy (50 keV) but significant increases at higher energies, indicating that longer crystal lengths enhance efficiency. Similarly, the efficiency increases with larger crystal radii across all energy levels suggesting substantial efficiency gains even at low energies. However, variations in crystal hole radius and depth, exhibit minimal impact on FEP efficiency across all tested energy levels. These findings highlight that optimizing crystal length and radius is more crucial for changing detector efficiency compared to modifying hole dimensions, providing valuable insights for optimizing Monte Carlo models and detector design. © 2024 Elsevier Lt
SOME PHYSICAL AND MECHANICAL PROPERTIES OF PARTICLE BOARDS PRODUCED WITH HAZELNUT HUSK AND ASTRAGALUS (Astragalus membranaceus) PLANT
No full textIn this study, under laboratory conditions, hazelnut husk and astragalus plant were mixed separately into black pine wood chips, and multi-purpose boards were produced from the obtained chips with urea formaldehyde glue. After the hazelnut husk and astragalus plant were dried and ground, they were added to the chip and glue mixture in certain proportions. Hazelnut husk mixture ratios were applied as 100 %; 0 %, 75 %; 25 %, 50 %; 50 %, 25 %; 75 %, 0 %; 100 % to black pine wood chip in the particle board mixture. These ratios were made in the same way for the astragalus plant. From these mixtures, chipboard blanks of 16 mm thickness and densities between 0,68 g/cm3 and 0,72 g/cm3 were produced. Density, moisture content, thickness increase, water intake, bending strength, modulus of elasticity in bending and tensile strength perpendicular to the surface were tested in physical and mechanical experiments. According to the results obtained, as the participation rate of hazelnut shells and astragalus increased, the durability properties of the panels decreased. At the same time, it shows that the technological properties of the panels produced by adding up to 25 % astragalus plant and hazelnut shells to the mixture comply with the standards. © 2025, Universidad del Bio-Bio. All rights reserved
The effects of sub-components of economic freedom on load capacity factor: Empirical analysis for MENA countries
No full textThis study investigates the effects of economic freedom sub-components on load capacity factor (LCF) in 12 MENA countries for 2017–2022. The 12 sub-components of the economic freedom index were used as independent variables, and the load capacity factor was used as the dependent variable. In the study, four-panel data models were created using the subcomponents of the economic freedom index, and a two-stage System-GMM was used. According to the study, while property rights reduce the load capacity factor, Judicial Effectiveness increases it. The effect of Government Integrity on the load capacity factor is statistically insignificant. While Government spending negatively affects the load capacity factor, Tax Burden and Fiscal Health are statistically insignificant. Business freedom affects the load capacity factor positively, but monetary freedom affects it negatively. Labour freedom is statistically insignificant. On the other hand, trade freedom and investment freedom have a positive impact on the load capacity factor, while financial freedom has a negative effect. © 2025 Elsevier Lt
The effect of omega-3 fatty acid use on women’s mental health in postpartum depression: a systematic review and meta-analysis study
No full textThe postpartum period is a period in which the mother experiences significant anatomical, physiological, and psychological changes as well as the transition to parenthood and assumes new roles and responsibilities1,2. In addition to the rapidly changing hormones and physiological state with childbirth, the responsibilities imposed on the mother, being a mother for the first time, lack of social support, lack of spousal support, and problems related to infant care can increase the risk of depression3,4.
Postpartum depression (PPD) causes a loss of physical and mental energy in the mother, negatively affecting her family, work, and social life and decreasing her quality of life. The worldwide prevalence of PPD is 15%, and this rate varies between 12.5 and 42.7% in Turkey5,6. Early diagnosis and treatment of PPD are important to protect maternal and infant health. Untreated PPD can turn into a progressive and chronic disease and cause increased mortality and morbidity in both mother and infant7,8. The main approach in the treatment of PPD is psychotherapy in combination with medication, but medication has many unknown effects on breast milk. The use of medication in the treatment of PPD reduces the amount of milk in the nursing mother and may cause side effects such as sedation, respiratory arrest, and neurobehavioral disorders in the infant2. Since the safety of drug use in the treatment of PPD is controversial, the effects of some nutrients in the prevention or alleviation of PPD are being investigated7,8.
It is known that adequate and balanced nutrition of the mother in the postpartum period is a basic requirement for the protection and development of mental health. It is emphasized that especially omega-3 fatty acids, vitamin B12, vitamin D, selenium, and iodine consumption are important for healthy mental health9. In the latest reports of the World Health Organization, the importance of seafood between pregnancy and mental health is emphasized10. In studies in the literature, it is recommended to take fish oils containing omega-3 fatty acids, which are an important nutrient in preventing PPD or alleviating its effects, by consuming fish or as a dietary supplement11,12. The aim of this study was to evaluate the effect of omega-3 fatty acid use on women's mental health in postpartum depression by systematic review and meta-analysis method.4010556
Ayak Banyosunun Yaşlılarda Uyku Kalitesi Üzerine Etkisi: Tek Kör Randomize Kontrollü Bir Çalışma
No full textObjective: This study was conducted as a single-blind, randomized controlled parallel-group study with 50 elderly individuals to investigate the effect of foot bath on sleep quality. Methods: The data were collected using the “Elderly Information Form” and the “Pittsburgh Sleep Quality Index (PSQI)” between 1 May 2022-1 July 2022 at a State Hospital in Gümüşhane province. The elderly in the foot bath group were given a foot bath with 41-42°C water for 20 minutes 50 minutes before normal sleep hours. No application was made to the control group except for the administration of data collection tools. The data were analyzed with Chi-square, Friedman, Wilcoxon Sign, and Mann-Whitney U tests. Results: It was determined that at least one of the total PSQI measurements and median scores of all subcomponents obtained from the elderly in the foot bath group differed depending on time (P.05). Again, All PSQI subcomponents and total PSQI scores, except for the subcomponent “Habitual Sleep Efficiency (C4)”, decreased throughout the application in the elderly in the foot bath group. Conclusion: As a result, a foot bath improved sleep quality in the elderly. In line with the findings from this study, it is recommended to compare the foot bath with multiple experimental groups for a longer period of time. © 2025, Ataturk Universitesi. All rights reserved
Utilization of desiccant silica-gel wastes for the mechanical and microstructural performances of self-compacting mortars
No full textThe existing exploratory focuses to examine the effect of relocating ordinary Portland cement (OPC) by divergent proportions (2.5–15 %, by vol.) of desiccant silica-gel waste (DSGW) on the strength/durability/microstructural traits of self-compacting mortars (SCMs). A large experimental programme comprising unconfined compressive- (UCS: 7/28/56/90 days) and flexural-strength (FS: 7/28/56/90 days), freeze-thaw (F-T: 50/100 cycles), sorptivity (Sp: 28 days), porosity (PT: 28 days) and scanning electron microscope (SEM: 28 days) tests was conducted on the fabricated SCMs. From the gathered findings, the replacing OPC by 10 % DSGW, compared to the Control, was detected to signify the most efficacious contribution on SCMs' strength (UCS/FS = +15.2/12.3 %), durability (UCS/FS-losses after 50 and 100 F-T = −4.7/−6.1 % and − 10.0/−12.7 %) behavior, which is in tune with the ameliorated microstructure (Sp = −35.2 %, PT = −19.2 % and SEM = higher C-S-H gel, less micro-crack). © 2024 Elsevier B.V