Policy Implications of Solutions of Dynamic Optimal Production Problems for Disinflationary Economic Policies

The speed of the application of current economic policies that are being followed in Turkey is a very important question. This paper uses the results of the solutions of optimal control theoretic inventory and production problems for companies to offer opinions on this question under various assumptions on interest rates. The most important result of the paper is that the rate of decline of interest rates is as important as the absolute level of interest rates for investors to start investing in inventories (consequently in machinery and other production infrastructure) which, in turn, implies growth of the economy.Disinflation, Control Theory, Economic Policy

OPTIMAL CONTROL THEORETIC APPROACH TO INVESTMENT IN DOCTORS

Health care is ever more important with aging population. Assuming the number of doctors per patient is one of the determinants of patient satisfaction, optimal investment in practitioner doctors, specialist doctors and foreign doctors are analyzed given the total number of doctors (domestic) are exogenously determined. The high cost of investment in specialist doctors are weighted against the high salaries of imported foreign doctors.An optimal control theory is employed to determine the optimal investment plans for the two alternative sources of specialist doctors to maximize the net (of costs) patient satisfaction over a fixed time horizon.It is found that a nation with insufficient number of specialist doctors at the beginning of the time horizon should increase the investment in local specialist doctors gradually while employing foreign doctors as to equate their salaries to the marginal satisfaction of the patients. An equilibrium point exists, and it is stable

OPTIMAL INCENTIVES FOR ECONOMIC GROWTH IN CENTRAL EUROPEAN COUNTRIES: A MICRO APPROACH

Financial crisis of 2008 and the ongoing pandemic are continuing to have a negative impact on the economies of all countries even tough interest rates have been decreased significantly. This paper attempted to view the problem from a micro point of view to suggest more effective incentives for growth. The specific objective of the study is to determine and examine the effects of these incentives on economic growth in Central European countries

A dynamic model of a nonlife insurance company

A Dynamics model of a nonlife insurance company is developed. Goodwill representing the awareness of the company by the public and the perceived quality of its services, and the technical capability representing the ability of the company to calculate the risk premium of the risks it considers to accept, are two state variables. The level of investment in advertising and quality improvement, and investments in technical capability are determined optimally to maximize the discounted profits of the company over an infinite horizon. The technical capability elasticity of number of customers and the claim ratio are shown to be determining parameters affecting the optimal paths of investments. The stability of equilibrium points are also shown to be dependent on these parameters

SUSTAINABILITY, CONSUMPTION, AND TECHNOLOGY

Sustainability of current economic system is analyzed in the face of growing population, accelerating exploitation of limited natural resources, and advances in technology. A Cobb-Douglas type of production function is assumed. Optimal control theory is employed to model the problem. It is proved that long term sustainability is possible, with or without population growth, only under certain conditions related to production and utility functions of the society.</p

Comparación entre los efectos de la dexmedetomidina, el fentanilo y el esmolol en la prevención de la respuesta hemodinámica a la intubación

ResumenJustificación y objetivosLa laringoscopia y la intubación pueden causar una respuesta hemodinámica. Varios medicamentos pueden ser usados para controlar esa respuesta. En este estudio, nuestro objetivo fue comparar los efectos de la dexmedetomidina, el fentanilo y el esmolol sobre la respuesta hemodinámica.MétodosNoventa pacientes programados para cirugías electivas con intubación endotraqueal, estado físico ASA I-II, y edades entre 21 y 65 años, se incluyeron en el estudio prospectivo, aleatorizado y doble ciego. Las presiones arteriales medias, sistólicas, diastólicas y las frecuencias cardíacas se midieron cuando los pacientes llegaron al quirófano y se registraron como valores basales. Los pacientes fueron aleatorizados en 3 grupos: el grupo i (n=30) recibió 1μg/kg de dexmedetomidina con infusión en 10min; el grupo ii (n=30) recibió 2μg/kg de fentanilo; el grupo iii recibió 2mg/kg de esmolol 2min antes de la inducción. Los pacientes fueron intubados en 3min. Las presiones medias, sistólicas y diastólicas y las frecuencias cardíacas fueron medidas antes de la inducción, antes de la intubación y durante los minutos 1, 3, 5 y 10 después de la intubación.ResultadosCuando los niveles basales fueron comparados entre los grupos, verificamos que en los minutos 5 y 10 la postintubación, las frecuencias cardíacas en el grupo i y las presiones arteriales medias, sistólicas y diastólicas en el grupo iii eran más bajas que en otros tiempos medidos (p<0,05).ConclusionesLa dexmedetomidina fue superior en la prevención de la taquicardia. El esmolol previno el aumento de las presiones arteriales medias, sistólicas y diastólicas después de la intubación. Concluimos que son necesarios algunos estudios adicionales para descubrir una estrategia que prevenga tanto el aumento de la presión arterial sistémica como la frecuencia cardíaca.AbstractBackground and objectivesLaryngoscopy and intubation can cause hemodynamic response. Various medications may be employed to control that response. In this study, we aimed to compare the effects of dexmedetomidine, fentanyl and esmolol on hemodynamic response.MethodsNinety elective surgery patients who needed endotracheal intubation who were in American Society of Anesthesiology I–II group and ages between 21 and 65 years were included in that prospective, randomized, double-blind study. Systolic, diastolic, mean arterial pressures, heart rates at the time of admittance at operation room were recorded as basal measurements. The patients were randomized into three groups: Group I (n = 30) received 1 μg/kg dexmedetomidine with infusion in 10 min, Group II (n = 30) received 2 μg/kg fentanyl, Group III received 2 mg/kg esmolol 2 min before induction. The patients were intubated in 3 min. Systolic, diastolic, mean arterial pressures and heart rates were measured before induction, before intubation and 1, 3, 5, 10 min after intubation.ResultsWhen basal levels were compared with the measurements of the groups, it was found that 5 and 10 min after intubation heart rate in Group I and systolic, diastolic, mean arterial pressures in Group III were lower than other measurements (p < 0.05).ConclusionsDexmedetomidine was superior in the prevention of tachycardia. Esmolol prevented sytolic, diastolic, mean arterial pressure increases following intubation. We concluded that further studies are needed in order to find a strategy that prevents the increase in systemic blood pressure and heart rate both

Classroom management strategies used to deal with unwanted behaviors encountered by pre-school teachersOkul öncesi öğretmenlerinin öğrencilerin istenmeyen davranışlarıyla baş etmede kullandıkları sınıf yönetimi stratejileri

The aim of this study is to identify classroom management strategies used to deal with unwanted behaviors encountered in the classes of pre-school teacher. Phenomenology patterns, one of the methods of qualitative research, were benefited in the research. The study group consists of 18 pre-school teachers all working in kindergartens in the city center of Igdir. To determine the study group, easy accessible case sampling, which is one of purposeful sampling methods, was benefited. The data, consisting of 3 questions asked to teachers, was obtained via semi-structured interview forms. Analysis of the results indicated not following classroom rules, misbehavior, complaining of friends and violence in classroom behavior as the mostly expressed complaints by teachers. This behavior was found to occur mostly during free time period and during when schools are just opened. It was found that teachers benefited from rewarding and consolidating, identifying the class rules and ignoring to cope with this unwanted behavior. Extended English summary is in the end of Full Text PDF (TURKISH) file.  ÖzetBu araştırmanın amacı, okul öncesi öğretmenlerinin sınıf içerisinde karşılaştıkları istenmeyen öğrenci davranışlarıyla baş etmede kullandıkları sınıf yönetimi stratejilerini tespit etmektir. Araştırmada yöntem olarak nitel araştırma yöntemlerinden olgubilim (fenomenoloji) deseninden faydalanılmıştır. Araştırmanın çalışma grubunu, tamamı Iğdır il merkezindeki bağımsız anaokullarında çalışan 18 okul öncesi öğretmeni oluşturmaktadır. Çalışma grubunun belirlenmesi için amaçlı örneklem seçimi yöntemlerinden kolay ulaşılabilir durum örneklemesinden yararlanılmıştır. Veriler, öğretmenlere sorulan 3 sorudan oluşan yarı yapılandırılmış görüşme formu ile elde edilmiştir. Analiz sonucunda öğretmenlerin en çok belirttiği istenmeyen davranışların sınıf kurallarına uymama, arkadaşlarını şikâyet etme ve şiddet türü davranışlar olduğu tespit edilmiştir. Bu davranışların en çok serbest zaman etkinliklerinde ve okulun yeni açıldığı dönemlerde ortaya çıktığı görülmüştür. Öğretmenlerin de bu istenmeyen davranışlara baş etmek için en çok ödül ve pekiştirme, sınıf kurallarını belirleme ve görmezden gelme stratejilerini kullandıkları tespit edilmiştir

INTERPRETABLE ESTIMATION OF SUICIDE RISK AND SEVERITY FROM COMPLETE BLOOD COUNT PARAMETERS WITH EXPLAINABLE ARTIFICIAL INTELLIGENCE METHODS

Background: The peripheral inflammatory markers are important in the pathophysiology of suicidal behavior. However, methods for practical uses haven’t been developed enough yet. This study developed predictive models based on explainable artificial intelligence (xAI) that use the relationship between complete blood count (CBC) values and suicide risk and severity of suicide attempt. Subjects and methods: 544 patients who attempted an incomplete suicide between 2010-2020 and 458 healthy individuals were selected. The data were obtained from the electronic registration systems. To develop prediction models using CBC values, the data were grouped in two different ways as suicidal/healthy and attempted/non-attempted violent suicide. The data sets were balanced for the reliability of the results of the machine learning (ML) models. Then, the data was divided into two; 80% of as the training set and 20% as the test set. For suicide prediction, models were created with Random Forest, Logistic Regression, Support vector machines and XGBoost algorithms. SHAP, was used to explain the optimal model. Results: Of the four ML methods applied to CBC data, the best-performing model for predicting both suicide risk and suicide severity was the XGBoost model. This model predicted suicidal behavior with an accuracy of 0.83 (0.78-0.88) and the severity of suicide attempt with an accuracy of 0.943 (0.91-0.976). Lower levels of NEU, WBC, MO, NLR, MLR and, age higher levels of HCT, PLR, PLT, HGB, RBC, EO, MPV and, BA contributed positively to the predictive created model for suicide risk, while lower PLT, BA, PLR and RBC levels and higher MO, EO, HCT, LY, MLR, NEU, NLR, WBC, HGB and, age levels have a positive contribution to the predictive created model for violent suicide attempt. Conclusion: Our study suggests that the xAI model developed using CBC values may be useful in detecting the risk and severity of suicide in the clinic

Effect of Potassium Aluminum Sulfate Application on the Viability of Fibroblasts on a CAD-CAM Feldspathic Ceramic before and after Thermocycling.

Potassium aluminum sulfate (alum) is a known adjuvant, which has been used as a mordant in textile industry for color fixation. This material has potential to be incorporated into dentistry for color stability, yet its toxicity first needs to be evaluated. The present study aimed to evaluate the cytotoxic potential of potassium aluminum sulfate (alum) on fibroblasts when applied onto feldspathic ceramic before and after thermocycling. Forty-eight feldspathic ceramic specimens were divided into four groups (FC: no alum application or thermocycling; FCT: thermocycling without alum application; FA: alum application without thermocycling; FAT: alum application and thermocycling) (n = 12). Cell viability was assessed by using a tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphnyltetrazolium bromide assay at 24 and 72 h, and cell cultures without any ceramic specimens served as control (C). One sample from each material group was further analyzed with energy dispersive X-ray spectroscopy (EDX). Cell viability at different time intervals within each group was analyzed with Friedman tests, while Kruskal-Wallis tests were used to compare the test groups within each time interval. Pairwise comparisons were further resolved by using Wilcoxon tests (a = 0.05). C had lower (p = 0.01) and FA had higher (p = 0.019) cell viability after 72 h. After 24 h, the highest cell viability was observed in C (p ≤ 0.036). After 72 h, the differences between C and FA, C and FAT, FC and FA, and FCT and FAT were nonsignificant (p &gt; 0.05). Cell viability was not affected by alum application or thermocycling at any time interval (p ≥ 0.631). EDX analysis showed an increase in potassium concentration in FA and FAT when compared with FC and FCT. Regardless of the time interval, alum application onto feldspathic ceramic and thermocycling did not influence the cell viability