An Alternative to Conventional Measurement Techniques for Evaluating Crack Propagations and Crack Width Openings

In the scope of this study, the capability of particle image velocimetry (PIV) method to monitor cracking behavior of cement-based materials was investigated. Load-crack opening width curves for beam specimens were obtained both from conventional measurement techniques (LVDTs) and from the PIV analysis. In order to evaluate the performance of the PIV results, the curves obtained from the LVDT readings were plotted together with PIV results, and good correspondence was found. Results represented that PIV technique can be used as an alternative to conventional measurement techniques during common structural tests, especially in bending tests, owing to its lower cost and strong ability to monitor cracking behavior. Additionally, in the case of monitoring the crack openings in beam specimens, the PIV technique can be assumed as a virtual crack mouth opening displacement (CMOD) gauge, without requiring prior knowledge of crack locations or any utilization of mechanical instrumentations; this showing the superiority of the technique over conventional mechanical instruments

A comparative evaluation of sepiolite and nano-montmorillonite on the rheology of cementitious materials for 3D printing

Through the last decade, methods of digital manufacturing of concrete gained a significant interest compared to conventional concrete. The main challenge in additive manufacturing (3D printing) is to design a highly thixotropic cementitious system. This study aims to investigate the use of sepiolite as a rheology modifier as a novel approach to improve the thixotropic behavior and adapt cementitious systems to 3D printing. To understand the influence of sepiolite on rheological properties, a comparative evaluation with nano-montmorillonite was established. The effectiveness of clay addition was also investigated in fly-ash amended cement-based materials. The rheological analysis was done on cement-paste samples containing both clays in terms of their effects on thixotropy, structural build-up, and recovery. A preliminary printability assessment was done with a lab scale printer having a ram extruder. The results show that the incorporation of clays increased the dynamic yield stress and time-dependent evolution of static yield stress. Moreover, the addition of clays improved the thixotropic behavior of cement-based systems, particularly those containing fly-ash. Herein, the sepiolite was found to be more effective compared to nano-montmorillonite in terms of improving thixotropy, structural build-up and recovery. The results showed that use of fly-ash enhances the printability of the mix for the specified extruder and the samples containing 1% nano-montmorillonite or 0.5% sepiolite can be printed. The positive effects of sepiolite were attributed to opposing surface charges of the clay layers and its micro-fibrous microstructure. The findings in this study enabled an in-depth understanding of the rheology and printability of fly-ash amended clay containing printable cement-based mortars

Erythropoietin Protects the Kidney by Regulating the Effect of TNF-α in L-NAME-Induced Hypertensive Rats

Background/Aims: Hypertension is the leading cause of death worldwide. Chronic high blood pressure induces inflammation. Tumor necrosis factor (TNF)-α plays a major role in inflammation and also depresses the synthesis of erythropoietin, which exerts protective effects on tissue; however, the mechanism is still unclear. We investigated the protective effect of erythropoietin against tissue damage caused by hypertension in the kidney and whether this effect was suppressed by TNF-α. Methods: First, we detected the optimum chronic dose for darbepoetin-α (Depo), which is a long-acting erythropoietin analog for rats. We separated 60 female adult rats into 6 groups: control, Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME), L-NAME+Depo, L-NAME+Remicade (an anti-TNF-α antibody), L-NAME+Depo+Remicade, Depo, and control. After 1 month of treatment, we measured cardiovascular parameters, took blood samples, sacrificed the rats, and removed kidneys for analyses. Results: The apoptotic index and the plasma and kidney mRNA levels of TNF-α increased in the L-NAME group and decreased in all other treatment groups. Macrophage accumulation increased in the L-NAME and L-NAME+Remicade groups, while it decreased in the Depo group. The mRNA abundance of TNF receptor 1 (TNFR1) decreased slightly in the Depo group and TNFR2 increased significantly in the same group. Conclusion: Erythropoietin protects kidney tissue against hypertension by preventing the apoptotic effects of TNF-α by blocking macrophage accumulation, decreasing TNF-α levels, and switching the TNF-α receptors from the apoptotic receptor TNFR1 to the proliferative receptor TNFR2

Borderline ovarian tumors: clinical characteristics, management, and outcomes - a multicenter study

Background: The optimal surgical management and staging of borderline ovarian tumors (BOTs) are controversial. Institutions have different surgical approaches for the treatment of BOTs. Here, we performed a retrospective review of clinical characteristics, surgical management and surgical outcomes, and sought to identify variables affecting disease-free survival (DFS) and overall survival (OS) in patients with BOTs

The prevalence of childhood psychopathology in Turkey: a cross-sectional multicenter nationwide study (EPICPAT-T).

Aim: The aim of this study was to determine the prevalence of childhood psychopathologies in Turkey

The prevalence of childhood psychopathology in Turkey: a cross-sectional multicenter nationwide study (EPICPAT-T)

Conclusion: This is the largest and most comprehensive epidemiological study to determine the prevalence of psychopathologies in children and adolescents in Turkey. Our results partly higher than, and partly comparable to previous national and international studies. It also contributes to the literature by determining the independent predictors of psychopathologies in this age group

Prevalence of Childhood Affective disorders in Turkey: An epidemiological study

Aim: To determine the prevalence of affective disorders in Turkey among a representative sample of Turkish population. Methods: This study was conducted as a part of the "The Epidemiology of Childhood Psychopathology in Turkey" (EPICPAT-T) Study, which was designed by the Turkish Association of Child and Adolescent Mental Health. The inclusion criterion was being a student between the second and fourth grades in the schools assigned as study centers. The assessment tools used were the K-SADS-PL, and a sociodemographic form that was designed by the authors. Impairment was assessed via a 3 point-Likert type scale independently rated by a parent and a teacher. Results: A total of 5842 participants were included in the analyses. The prevalence of affective disorders was 2.5 % without considering impairment and 1.6 % when impairment was taken into account. In our sample, the diagnosis of bipolar disorder was lacking, thus depressive disorders constituted all the cases. Among depressive disorders with impairment, major depressive disorder (MDD) (prevalence of 1.06%) was the most common, followed by dysthymia (prevalence of 0.2%), adjustment disorder with depressive features (prevalence of 0.17%), and depressive disorder-NOS (prevalence of 0.14%). There were no statistically significant gender differences for depression. Maternal psychopathology and paternal physical illness were predictors of affective disorders with pervasive impairment. Conclusion: MDD was the most common depressive disorder among Turkish children in this nationwide epidemiological study. This highlights the severe nature of depression and the importance of early interventions. Populations with maternal psychopathology and paternal physical illness may be the most appropriate targets for interventions to prevent and treat depression in children and adolescents