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Safety stock is an important method to overcome variability in inventory management. The classical approach to safety stock decisions relies on historical demand and lead time statistical data, which may not capture the uncertainty and complexity of the real world. Human knowledge and experience are valuable assets for making better decisions, especially when facing unpredictable situations. The fuzzy method is widely used for employing human intuition for decisions. When fuzzy opinions are input, decisions can be made proactively rather than reactively while benefiting from future predictions. The paper aims to integrate human intuition using Hexagonal Type-2 Fuzzy Sets (HT2FS) for safety stock management. HT2FS is a generalization of Interval Type-2 Fuzzy Sets that can represent more uncertainty in the membership functions. Predictions may be integrated into the safety stock models using human intuition. The proposed model uses novel fuzzy approaches to integrate human intuition into the traditional safety stock model. Applying fuzzy sets to safety stock management allowed experts' opinions under fuzzy logic to be integrated into decision-making. The proposed novel approach uses the centre of gravity method of Polygonal Interval Type-2 Fuzzy sets for defuzzification, which is a computationally efficient method that can handle any shape of the footprint of uncertainty. A mathematical model is developed to validate fuzzy opinions that may replace historical data. The data is received from a real-life case, and human intuition is integrated using an expert’s input. After the validation, a real-life numerical example has been considered to illustrate the model and its validity compared to the classical model. The outcomes show that the proposed model may contribute to the classical models, mainly when experts' inputs offer good predictions. When expert opinion on HT2FS is used for a real-life case, the results show that the expert's better representation of future variances lowers total cost by 2.8%. The results, coupled with the sensitivity analysis, underline that the proposed approach may contribute to the literature on safety stock management. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of high intensity laser therapy (HILT) on pain, functional status, hand grip strength, and median nerve cross-sectional area by ultrasonography in patients with carpal tunnel syndrome. Sixty patients who were diagnosed with carpal tunnel syndrome were included in the study. The patients observed during the research were randomly divided into two groups with 30 patients in each group. Splint+ exercise and HILT (pulsed mode with a power of 8.0 W and energy density of 8 J/cm2 for 1.40 minutes for every 25 cm2, continuous mode with a power of 3.0 W and energy density of 80 J/cm2 for 11 minutes for each 25 cm2; total 10 sessions 5 days a week) were applied for 2 weeks for the first group, and splint+exercise and sham laser treatment were applied for 2 weeks for the second group. Randomization was undertaken with the assistance of a computer-generated random number table before beginning the treatment processes. The patients were evaluated with the determined scales before the treatment, at the end of the treatment, and at the 3rd month. Hydraulic hand dynamometer was used to measure hand grip strength, visual analog scale (VAS) for pain, Boston CTS Questionnaire to assess function, and ultrasonography to measure median nerve cross-sectional area. The impact of time on the change in VAS levels was found to be of statistical significance within each group of patients (p<0.001), but between-group comparisons did not yield significant results (p<0.454). The effects of time on variations in Boston CTS Questionnaire scores were found to have been of statistical significance for both groups (p<0.001), but significance was not subsequently observed when the results of the two groups were compared on a between-group basis (p=0.226 and p=0.973 for the FSS and SSS, respectively). While time had a statistically significant effect on the change in hand grip strength for both groups (p=0.000), between-group comparisons statistical significance finding in favor of HILT was found in the early period (p=0.012). The time-group association patterns of the groups showed significant difference (p=0.025). While time had a statistically significant effect on the changes in the median cross-sectional areas of the nerve for the patients of both treatment groups (p<0.001), between-group comparisons yielded no findings of statistical significance (p=0.438). The time-group relationship patterns of the groups were found to reflect statistical significance (p=0.001). In conclusion, the results of the research presented here have confirmed that hand grip strength may increase and the median nerve's cross-sectional area may decrease upon the application of high-intensity laser for individuals experiencing CTS. However, this effect was demonstrated here only in the short-term and the evidence was not maintained through the course of follow-up of a longer duration. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between intellectual capital and firm performance in the period of 2010-2020 using the data of 2.619 listed manufacturing firms from Brasil, India, Indonesia, South Africa, and Turkey. The first contribution of the study to the literature is the use of data from "fragile five" countries, which are the most delicate economies among developing countries, rather than the data from developed countries. Secondly, instead of sectors such as banking, technology, and services, which can be understood intuitively as being intellectual capital intensive, the manufacturing sector firms, which are known as physical and financial capital intensive, are examined. Finally, the most appropriate econometric method for the characteristics of the data is determined and applied. The findings of the study show that the capital employed efficiency has a positive effect on firm performance in all countries. The results regarding human capital efficiency, which is an important component of intellectual capital, point out that human capital is still underestimated in developing countries, and its effect on firm performance cannot be observed due to the lack of necessary investment in human capital. It is observed that the structural capital component of intellectual capital is an element that has been recognized and invested in developing countries. [ABSTRACT FROM AUTHOR]

In this study, tri generation system which is one of the in place energy generation methods is analyzed thermodynamically by using EES (Engineering Equation Solve) software. The electricity capacity, exergy losses, and exergy efficiency was calculated which of the case study of consuming of 1000 m3 natural gas. In the pre-determined conditions, it is calculated that a trigeneration system which consumes 1000 m3 of natural gas per month has a capacity of generating the electrical energy of 3.018 kW, heating capacity of 10.12 kW and cooling capacity of 6.574 kW. It is calculated that such a trigeneration system which has such capacities of production has a thermal efficiency of 24%, COP of 0.68 and total exergy loss of 8.49 kW. The total loss of exergy at each system component has a percentage of; 28% at the boiler, 24% at the condenser I, 14% at the absorber, 12% at the generator 11% at the condenser II, 11% at the evaporator and 2% at the turbine respectively. These results that are obtained have shown resemblance with the results that have been published previously. [ABSTRACT FROM AUTHOR]

This study investigates the financial and institutional determinants of corporate cash holdings in Turkey over the period of 2010 and 2019 using a broad data of non-financial public companies. The results show that growth opportunities, leverage, firm size, net working capital, cash flow, and capital expenditures are important financial factors in determining cash holdings. While positive effect of growth opportunities and negative effect of capital expenditure are in line with the expectations of the trade-off and pecking order theories, the positive effects of firm size and cash flow coincide pecking order and free cash flow theories. The negative effect of leverage corresponds to all three theories. However the positive sign of corporate governance dummy is not statistically significant. Thus, the hypothesis, which suggests that corporate governance affects the corporate cash holdings, could not be supported. The results also show that companies have target cash holdings level and adjust toward the target. [ABSTRACT FROM AUTHOR]

Objectives: Transposition of the great arteries (TGA) is a rare congenital heart disease that occurs in 3 in 10,000 newborns and is rapidly fatal (90%) within one year if left untreated. The prognosis of this pathology changed after introducing an early arterial switch operation (ASO), while the left ventricle could still adapt to systemic high-pressure conditions. Appropriate regulation of thyroid hormones positively impacts metabolism, cardiac function, and postoperative recovery. Therefore, regular thyroid hormone monitoring and thyroid function monitoring of TGA patients may help to improve the health status and prognosis of this group of postoperative patients. Methods: In our study, 127 patients who underwent ASO at our pediatric cardiac surgery clinic between 01.01.2014 and 18.09.2021 were retrospectively analyzed and included. Among the patients, 43% (n=54) were females, and 57% (n=73) were males. Results: The coronary arteries were normal in 89.7% (n=114) and abnormal in 10.3% (n=13) of the patients. Twenty-one of the patients exited, and mortality was calculated to be 16.5%. There were no significant differences in mortality or thyroid stimulating hormone (TSH), free thyroxine (T4), or free triiodothyronine (T3) values (P=0.674, P=0.345, P=0.478). In our study, in which we investigated the effect of thyroid hormone levels on prognosis in neonatal patients with TGA with normal free T3, T4, and TSH values, we found that TSH levels were greater in the group with advanced aortic regurgitation and exitus, although the effect of thyroid hormones on postoperative results was not statistically significant. Conclusions: Congenital hypothyroidism is a common disease with cardiac effects. During the neonatal period, this disease may conceal itself. Careful, expert clinical follow-up and clinical trials are crucial to improve outcomes in the surgical treatment of transposition of the great arteries, a complex congenital heart disease. [ABSTRACT FROM AUTHOR]

Objective: To investigate the perioperative and postoperative effects of preoperative levosimendan use in coronary artery patients with low ejection fraction (EF) (<40%). Material and Methods: A total of 6,571 coronary bypass patients who were treated at Kartal Koşuyolu High Specialization Training and Research Hospital between 2016 and 2019 were scanned, and 132 patients with preoperative EF below 40% were retrospectively analyzed. The patients were divided into 2 groups as those who received preoperative levosimendan (Group 1: 90 patients) and the control group, who did not receive it at all (Group 2: 42 patients). All of the patients included in the study were onpump coronary bypass patients and excluded off-pump bypass, emergency bypass, and other concomitant procedures. Results: In terms of EF values, improvements over time were significantly different in favor of Group 1 (p<0.043). The duration of the intensive care unit stay in Group 1 was longer (p<0.047). The changes in patients in terms of postoperative venous oxygen saturation over time were found to be statistically positive in favor of Group 1 (p<0.042). Mortality was observed in 5 patients in the postoperative early period (first 30 days), all of whom were from Group 1. However, no statistical difference was observed. Conclusion: Preoperative use of levosimendan in coronary artery patients with low EF improved some hemodynamic parameters; however, it did not make a significant hemodynamic and clinical contribution to surgery success in high-risk patients. [ABSTRACT FROM AUTHOR]

Background: The postoperative phase of cardiac surgery in pediatric patients with congenital heart disease often involves the management of pulmonary hypertension, which can significantly affect recovery and long-term prognosis. Inhaled iloprost is a potent acute pulmonary vasodilator with a rapid onset of action and has been shown to be effective and safe in patients with pulmonary arterial hypertension, improving clinical parameters by lowering pulmonary artery pressure. In our study, we will share the results of patients with pulmonary hypertension after pediatric cardiac surgery in whom we used inhaled iloprost. Results: A total of 9 patients who received inhaled iloprost between 2020 and 2023 were included in the retrospective study. The age of the patients ranged between 10 days and 11 months, with a mean of 207.77 days (6.92 months) ± 105.78 days (3.52 months). Five patients were male (55.55%), and four were female (44.45%). Three of the patients had trisomy 21 (33.3%) genetic mutations. Conclusions: The limited number of case series in the literature support the potential of inhaliloprost as an effective and safe therapeutic option for the treatment of pulmonary hypertension in the pediatric population after congenital heart surgery. The findings of this study support the literature and suggest that inhaliloprost is effective. Due to the limited number of patients, further research is needed to determine the safety and efficacy of these drugs, especially to determine the dose, route, and duration of administration in intubated patients. [ABSTRACT FROM AUTHOR]

Background: Diaphragmatic paralysis due to phrenic nerve injury is a rare but potentially serious complication following congenital cardiac surgery, with reported incidences ranging from 0.28 to 5.6%. Early plication has been recommended for children diagnosed with diaphragmatic paralysis, especially those requiring prolonged respiratory support after cardiopulmonary bypass. It is important to note that late plication may jeopardize the results of successful surgical plication due to diaphragm atrophy. Results: This retrospective study was performed between May 2020 and June 2023. Patients who could not be weaned from the ventilator and underwent diaphragmatic plication in symptomatic patients after phrenic nerve injury were included in the study. During the study period, 22 (3.5%) of 624 pediatric patients operated for congenital heart disease required diaphragm plication. The mean age of the patients ranged from 1 month to 13 years with a mean of 23.88 ± 37.99 months. Fourteen (63.6%) of the patients were female, and 8 (36.4%) were male. Two of the patients (9%) were exited due to ventilator-associated pneumonia and sepsis. Conclusions: In conclusion, diaphragmatic paralysis after congenital heart surgery is a rare but important complication that can lead to serious respiratory and cardiac problems. Diaphragmatic plication has been shown to be an effective intervention for pediatric patients with the potential to improve pulmonary function, reduce dyspnea, and minimize complications associated with diaphragmatic paralysis. Careful consideration of patient selection, timing, and potential complications is crucial in optimizing the outcomes of this surgical intervention. [ABSTRACT FROM AUTHOR]