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Copyright of Optimum: Journal of Economics & Management Sciences / Ekonomi ve Yönetim Bilimleri Dergisi is the property of Optimum: Journal of Economics & Management Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Liberalization policies in the electricity markets have led to an increase in the number of electricity generation companies (GenCos). GenCos develop competitive strategies to thrive in the market and ensure long-term sustainability. In the day-ahead market (DAM), GenCos submit bids for the electricity quantity they plan to generate the next day. Deviating from the committed electricity quantity leads to either selling surplus electricity at a positive imbalance price (lower than the market price) or incurring a penalty for missing electricity at a negative imbalance price (higher than the market price). In this study, we develop a bid strategy for renewable GenCos participating in the Turkish DAM. The proposed approach involves utilizing a neural network (NN) to determine the bid quantity. The proposed NN aims to minimize a cost function considering both negative and positive imbalance prices, as opposed to the classical NN of minimizing the mean squared error. The proposed approach outperforms the classical NN , yielding a 2.38% (potentially reaching up to 7.43%) improvement in revenue generation. Moreover, we perform a comprehensive sensitivity analysis, specifically focusing on changes in penalty coefficients. Notably, as penalty coefficient ranges widen, our approach refines bidding strategy more effectively than alternatives. • The proposed NN model presents a bid strategy for renewable GenCos. • The model cost function takes into account negative and positive imbalance prices. • Thanks to its single-stage structure, the model directly determines the optimal bid. • The model is practical and straightforward to implement. • The model demonstrates superior performance compared to the classical NN. [ABSTRACT FROM AUTHOR]

Copyright of Muhasebe ve Vergi Uygulamalari Dergisi (MUVU) / Journal of Accounting & Taxation Studies (JATS) is the property of Ankara Serbest Muhasebeci Mali Musavirler Odasi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anatolian Journal of Cardiology / Anadolu Kardiyoloji Dergisi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT In the current study investigated the psychopathologies of parents, family functioning, child temperament characteristics, and attachment of kindergarten and primary school‐age children who were brought to the child and adolescent psychiatry outpatient clinic due to school refusal behavior. Fifty‐two children with school refusal and 64 children without school refusal and their parents participated in the current study. School Refusal Assessment Scale, Systemic Family Functionality Scale(SFFS), Family Harmony Scale(FHS), Kerns Secure Attachment Scale(KSAS), Temperament Scale for Children(TSC), and Depression Anxiety Stress Scales(DASS) for parents were used. It was determined that, compared to children without school refusal, the children with school refusal had lower KSAS score(mother)(p = 0.049), higher DASS‐stress and anxiety(mother) scores(p = 0.014 and p = 0.020, respectively), lower TSC‐Responsiveness/Reactivity subscale score (p = 0.005), lower SFFS‐intrafamilial support and SFFS‐intrafamilial connection scores (p = 0.002 and p < 0.001, respectively), and lower FHS‐total score (p = 0.002). It was determined that school refusal was 11 times more common in children who had difficulty adjusting to school in previous years. Each point increase in the SFFS‐intrafamilial connection score reduced school refusal by 30%. In the current study shows that among the interventions required for treatment, the family should also be targeted in addition to the child and adolescent. Therefore, it is essential to identify factors such as parents' psychopathology and their roles in the family, family functioning, and family harmony in school refusal. Because parents play a crucial role in both the development and maintenance of school refusal, using more parent‐targeted strategies or techniques is necessary to improve interventions. [ABSTRACT FROM AUTHOR]

Introduction: Reduced exercise capacity is of clinical importance. Sometimes no corresponding cardiovascular disease can be found to explain this condition. We hypothesized that coronary microvascular dysfunction may have an effect on exercise capacity in patients without apparent cardiovascular disease., Methods: Fifty patients (33 female, mean age 46.8 ± 12.4 years) without coronary artery or other cardiac disease were enrolled. Coronary microvascular function was evaluated by measurement of coronary flow reserve (CFR) during transthoracic pulsed-wave Doppler echocardiography with pharmacological stress. CFR was calculated as the ratio of hyperemic to baseline peak diastolic velocities after dipyridamole infusion. Exercise capacity was determined by treadmill exercise testing. Exercise time, metabolic equivalent (MET), and Duke treadmill score (DTS) were recorded and compared with the CFR data., Results: CFR was correlated with exercise time (r=0.376, p=0.007), MET (r=0.435, p=0.002) and DTS (r=0.458, p=0.001). Exercise time, MET, and DTS were lower in patients with impaired CFR (<2) than in those with normal CFR (2) (5.3 ± 1.8 min vs. 8.6 ± 2.7 min, p<0.001; 7.3 ± 3.1 vs. 11.4 ± 2.8, p=0.002; -1.75 (-5.9, 5.0) vs. 7.5 (5.2, 9.41), p<0.001; respectively). CFR was lower in patients with MET7 as compared to patients with MET>7 (2.0 ± 0.5 vs. 2.6 ± 0.6, p=0.015)., Conclusions: CFR is associated with exercise capacity. Thus coronary microvascular dysfunction may be a reason for reduced exercise capacity in patients who have no apparent cardiovascular disease.

Objective: Coronary microvascular function among offspring of patients with diabetes mellitus might be compromised when compared to persons with no first-degree relative with diabetes mellitus. The aim of the study was to evaluate effect of family history of type-2 diabetes on coronary flow reserve., Methods: In this observational study, we evaluated coronary flow reserve (CFR) via echocardiography of 95 subjects having a biological parent with type-2 diabetes and 34 healthy volunteers without any biological parent with type-2 diabetes. We have analyzed possible association with CFR and homeostasis model assessment - insulin resistance (HOMA-IR). Comparison analyses were made using independent samples t test, Chi-square test and one-way ANOVA. Association of independent variables with CFR was obtained by correlation analysis and stepwise linear regression model including potential confounders., Results: CFR was significantly lower in the positive family history group than in the controls. Moreover, when compared with controls, the subgroup of insulin-sensitive subjects in the positive family history group also had significantly reduced CFR (2.67±0.28 vs. 2.83±0.19; p=0.01). Correlation analysis revealed that CFR was inversely correlated with HOMA-IR, (r=-0.433), fasting glucose (r=-0.331), fasting insulin (r=-0.396), and hemoglobin (Hb)A1c (r=-0.405). When the positive family history group was divided into tertiles of insulin resistance (HOMA-IR <1.3, 1.3-2.6, and >2.6; Groups 1-2, and 3), there was a significant difference in CFR between Groups 1 and 2 and between Groups 1 and 3 (p<0.05 for all). Though statistically not significant, there was also a difference in CFR between Groups 2 and 3. In a linear regression model, only fasting glucose level was independent predictor of CFR (β=-677; p value =0.001, 95% CI: -0.061 and -0.019)., Conclusion: Nondiabetic first-degree relatives of patients with type-2 diabetes are at increased risk of developing coronary microvascular dysfunction.

In acute coronary syndromes (ACS), oxidation and inflammation have very important roles and in-vitro studies have demonstrated that gamma-glutamyl transferase (GGT) participates in such oxidative and inflammatory reactions. We aimed to evaluate the prognostic value of baseline serum GGT activity on the development of major adverse cardiac event (MACE) in the follow-up of the patients with ACS in coronary care unit (CCU), after 1 and 6 month periods. We included 117 patients (mean age: 61.2+/-11.3 years, 93 males) hospitalized in CCU with the diagnosis of ACS. All had baseline serum GGT activity and were free of systemic and hepatobiliary disease. MACE was defined as the composite of mortality from cardiac causes, recurrent hospitalization with ACS and nonfatal recurrent myocardial infarction diagnoses, to need for coronary revascularization during CCU, over 1 and 6 month follow-up periods. During the follow-up of CCU, MACE occurred in 17 (14.5%) patients (two died). Serum GGT activity was significantly higher in the patients with MACE than those free of MACE (P=0.001) and GGT was found as the independent predictor of the development of MACE-CCU [relative hazard: 1.05, 95% confidence interval (CI): 1.01-1.09, P=0.007]. During the follow-up of 1 month, MACE occurred in 23 (20.0%) patients (five died). Serum GGT activity was significantly higher in patients with MACE than those free of MACE (P=0.021) and GGT was found as the independent predictor of the development of MACE-1 month (relative hazard: 1.04, 95% CI: 1.01-1.08, P=0.039). During the follow-up of 6 months, MACE occurred in 24 (21.8%) patients (two died). Again, GGT was significantly higher in patients who developed MACE than those free of MACE (P=0.001) and GGT was found as the independent predictor of the development of MACE-6 months (relative hazard 1.06, 95% CI: 1.03-1.10, P<0.001). Serum GGT activity was found to be an independent predictor of the development of MACE in the patients with ACS during CCU, over 1 and 6 month follow-up periods.