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Yayın Strengthening of reinforced concrete beams without transverse reinforcement by using intraply hybrid composites(Elsevier Ltd, 2021-12) Çakır, Ferit; Acar, Volkan; Aydın, Muhammet Raci; Akşar, Bora; Yıldırım, PınarConcrete is currently among the most widely used materials all around the world. The main advantages of concrete include durability, versatility, and high compressive strength, but significant disadvantages include low tensile strength, low shear strength, and low ductility. To eliminate these disadvantages, longitudinal and transverse reinforcements are usually preferred. Steel is widely used as a reinforcement material in the world, but there is still research underway to find alternative materials. In recent decades, composite materials have been used to reinforce concrete instead of steel materials. This study focuses on Intraply Hybrid Composites (IHCs), which are had an important place in the composite industry and examines how these composites affect concrete beams as far as their shear strength is concerned. For this purpose, A length of 2 m RC beams, with no transverse reinforcement (RC2.0), is prepared and then reinforced with three IHCs, Aramid-Carbon (AC2.0), Glass-Aramid (GA2.0) and Carbon-Glass (CG2.0). After U-shape strengthening, the specimens are inspected in four-point bending tests and the effects of the IHCs are investigated on the shear strength of the beams. The experimental results show that there is an increase of 4.36%, 10.62%, and 15.28% in the ultimate load capacity of AC2.0, CG2.0, and GA2.0, respectively, compared to reference specimen, RC2.0. Furthermore, the type of hybrid composite has a direct impact on the failure modes of the RC beams. Consequently, the IHCs can provide a significant contribution to the structural behavior of RC beams.Yayın Effects of o-tDCS and tDCS on maximal grip strength(Istanbul University Press, 2024-10-14) Şeker, Sercan; Eskicioğlu, Gaye; Küçük, Zeynep; Karamürsel, SacitObjective: The aim of the current study was to examine and compare the effects of oscillatory transcranial direct current stimulation (o-tDCS) and transcranial direct current stimulation (tDCS) against sham stimulation on maximal intermittent gripping performance. Materials and Methods: The study included 25 healthy, right-handed male subjects (age range 18-35 years) who were randomly assigned to three separate groups: o-tDCS (n=9), tDCS (n=8) and sham (n=8). The left primary motor cortex was selected as the anodal stimulation region, and a cathode electrode was placed over the right supraorbital area. A hand dynamometer is used to measure the maximum grip values during a maximal intermittent gripping task. Between-group comparisons were made; for each stimulation group, baseline grip values of the participants were compared with those obtained during stimulation. Results: Although the o-tDCS group showed slightly better improvements in maximal and mean strength, there were no statistically significant differences between stimulation groups (p>0.05). Conclusion: The findings of the study suggest neither o-tDCS nor tDCS has a significant facilitative impact on grip strength values in healthy young males, most likely due to a ceiling effect in this population.Yayın Efficacy, all-cause discontinuation, and safety of serotonergic psychedelics and MDMA to treat mental disorders: a living systematic review with meta-analysis(Elsevier B.V., 2025-12) Højlund, Mikkel; Yılmaz Kafalı, Helin; Kırmızı, Begüm; Fusar-Poli, Paolo; Correll, Christoph U.; Cortese, Samuele; Sabé, Michel; Fiedorowicz, Jess; Saraf, Gayatri; Zein, Josephine; Berk, Michael; Husain, Muhammad I.; Rosenblat, Joshua D.; Rubaiyat, Ruby; Corace, Kim; Wong, Stanley; Hatcher, Simon; Kaluzienski, Mark; Yatham, Lakshmi N.; Cipriani, Andrea; Gosling, Corentin J.; Carhart-Harris, Robin; Tanuseputro, Peter; Myran, Daniel T.; Fabiano, Nicholas; Moher, David; Mayo, Leah M.; Nicholls, Stuart G.; White, Tracy; Prisco, Michele De; Radua, Joaquim; Vieta, Eduard; Ladha, Karim S.; Katz, Jay; Veroniki, Areti A.; Solmi, MarcoSerotonergic psychedelics and 3,4-methylendioxtmethamphetamine (MDMA) are promising treatments for mental disorders with a continuously evolving evidence base. We searched Pubmed/Scopus/clinical trial registries up to 08july2025 for double-blind randomized controlled trials (RCTs) testing MDMA or serotonergic psychedelics in patients with mental disorders. Primary outcomes were change in disease-specific symptoms and all-cause discontinuation. Standardized mean differences (SMD) and relative risk (RR) were estimated using random-effects meta-analysis. Risk of bias (RoB) was assessed with Cochrane’s RoB-tool version 2 and certainty of evidence with GRADE. The review is maintained as living systematic review ( https://ebipsyche-database.org/ ). We included 30 RCTs (1480 participants; female=45.8 %; with psychological support=83.3 %; high RoB=83.3 %). In post-traumatic stress disorder (PTSD), MDMA reduced PTSD symptoms compared to any control ( k = 11; SMD=-0.85 [-1.09; -0.60]; I2=0 %; GRADE=low). In major depressive disorder (MDD), psilocybin/ayahuasca/LSD reduced depressive symptoms ( k = 8; SMD=-0.62 [-0.97; -0.28]; I2=55 %; GRADE=very low). In anxiety disorders, both MDMA and serotonergic psychedelics reduced anxiety symptoms (SMDMDMA=-1.18 [-2.04; -0.32]; I2=0 %; k = 2; GRADE=low and SMDserotonergic=-0.88 [-1.70; -0.06]; I2=54 %; k = 5; GRADE=very low). In alcohol use disorder, neither psilocybin nor LSD reduced abstinence rates ( k = 6; RR=1.42 [0.89; 2.26]; I2=7 %; GRADE=very low). In attention-deficit hyperactivity disorder (ADHD), LSD did not reduce ADHD symptoms ( k = 1; SMD=0.22 [-0.32; 0.76]; GRADE=very low). Moderate certainty in evidence was only found for MDMA on PTSD symptoms when compared to placebo. MDMA/serotonergic psychedelics were not associated with higher risk of all-cause discontinuation (RRMDMA=0.74 [0.32; 1.72]; RRserotonergic=0.81 [0.56; 1.15]). Overall, MDMA/serotonergic psychedelics are promising for the treatment of PTSD, MDD, and anxiety disorders with moderate to large effect sizes. Pragmatic trials, long-term, head-to-head trials exploring the role of psychological support, aiming to identify predictors of response, and accounting for expectancy and functional unblinding are needed. Studies addressing these limitations will likely be required for regulatory approval of psychedelic drugs.Yayın The mediating effect of self compassion in the relationship between job stress and burnout levels among employees(SAGE Publications Inc., 2026-02-13) Günay, Ezgi; Ünver, Buket; Yılmaz, SimayObjective: This study investigates the role of self-compassion as a mediator in the relationship between job stress and burnout among employees. While job stress is widely recognized as a critical factor leading to burnout, it has been suggested that self-compassion may be associated with a reduction in these negative effects. Method: Participants were 429 actively employed adults living in Turkey (50.6% female). The data were gathered using an online administration of standardized psychological scales, that is, Job Stressor Appraisal Scale, Copenhagen Burnout Scale, and Self-Compassion Scale. Four dimensions of work stress “Role and Workload, Role Inadequacy, Organizational Rules & Practices, and Subordinate Relations” are taken into consideration in the volumetric model. Path analysis with bootstrapping (5,000 resamples) was implemented using Mplus statistical software, with gender, economic condition, and way of working during COVID-19 as covariates. Findings: The model fit was acceptable in path analysis. Role and workload and role inadequacy had a significant direct impact on burnout. Self-compassion had a significant mediating impact on the relationship between role and workload and burnout and the relationship between role inadequacy and burnout. Conversely, for organizational rules and practices and subordinate relations, both direct and mediating effects were non-significant. The model accounted for 21% and 52% for variance in self-compassion and burnout, respectively. Conclusion: This study emphasises the mediating role of self-compassion in the effect of job stressors on burnout. These findings suggest that interventions promoting self-compassion in the workplace may be effective in reducing employee burnout.
