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In the past 20 years, commodity markets have been examined under the hypothesis of whether the prices exhibit recurrent patterns or follow the stochastic processes. In this study, we analyze both global energy markets and food markets to detect the presence of multiple equilibria, which may lead to higher spikes in prices and to the occurrence of intermittency. This study focuses on daily prices in Brent petrol and Natural gas markets from 23 May 2017 to 23 May 2022. This time interval covers the period where extraordinary economic and financial policies have been preferred in countries worldwide amid the Covid-19 pandemic crisis. On the other hand, the study investigates global Food index monthly data from 2007M11 to 2022M4. Similarly, the time interval under examination points out the effects of the 2008 global crisis where expansionary monetary policies have been implemented both by the Federal Reserve of the U.S and the European Central Bank. We employed the phase-space reconstruction method for the Crude oil Brent Europe and spot Natural gas prices series, and global Food index data respectively. The main findings of the study demonstrate that commodity markets do not converge to a unique equilibrium level, instead multiple equilibria persist and chaotic behavior occurs. The presence of multiple equilibria leads to an increase in complexity and recurrently causes volatility in commodity markets, which may have spillover effects on other financial markets. Our results suggest that these effects simultaneously increase global inflationary pressures. From the perspective of policy making, it is crucial to establish a strategy to eliminate multiple equilibria and prevent high price spikes. Our findings have important implications for Central bank policies in emerging markets and portfolio and risk management.

This paper aims to investigate the mediating role of explicit knowledge sharing in the relationship between empowering leadership and proactive work behavior in defense industry enterprises. The sample of this study consists of defense industry enterprises operating within the borders of Turkey. A total of 305 survey data were collected from these enterprises using the random sampling method, and 5 survey data among them were eliminated because of missing information, and analyzes were made with a total of 301 survey data. Structural equation modeling was used to test the research model and hypotheses. According to the analysis results of the study, empowering leadership has a positive effect on proactive work behavior and explicit knowledge sharing. In addition, it has been understood that open information sharing has a positive effect on proactive work behavior. Finally, it has been revealed that explicit knowledge sharing has a mediating role in the relationship between empowering leadership and proactive work behavior.

The rapid growth in civil aviation operations in recent years has raised expectations from flight attendants. Their duties have been intensified, and flight attendants have become subject to physical and mental fatigue due to irregular sleep, inadequate rest time, and long working hours. This study investigates the causes and effects of fatigue among flight attendants of a Turkish airline company through a self-administrated questionnaire. The survey is run online by 152 flight attendants. The results show that flight attendants have trouble falling asleep before flight duty. Before night flights and during layovers, the sleep duration is dramatically low. The results also reveal that factors related to scheduling, i.e., long duty days, night flights, and consecutive working days, play an essential role in fatigue. Thus, airline companies should revise their scheduling practices. In balancing work and social life, men struggle more than women, and married flight attendants have more difficulty than single ones. The findings provide valuable insights for airline companies and policymakers to seriously manage fatigue-related factors to ensure the safety of aviation operations and the well-being of flight attendants.

In this study, the relationships between cargo revenues, ancillary revenues and net profitability of airline companies were examined in the examples of three full-service airline companies (Turkish Airlines, American Airlines, Delta Air Lines). Methodologically, a logarithmic econometric model was used in which cargo revenues and ancillary revenues were included as independent variables and net profit as the dependent variables. The data used for the period 2014Q1-2019Q4 were collected from the annual reports on the official websites of related airline companies and The International Air Transport Association (IATA). EViews 10 and STATA-15 versions, which are the most modern econometric analysis programs that can be used to control the stationarity, were used in the analysis of the data. In addition to econometric analyzes and general statistics, Cross Section dependency tests, CADF second-generation unit root tests, Delta slope homogeneity tests, Panel cointegration analysis, Westerlund Panel cointegration tests and Dumitrescu Hurlin Panel Causality tests and Breusch Pagan LM Tests were also performed. The study revealed that there is cointegration between cargo revenues, ancillary revenues and net profit, and there is a one-way causality relationship from both cargo revenues to net profit and from ancillary revenues to net profit. The study also indicated a positive correlation between cargo revenues and ancillary revenues and net profit. In other words, cargo revenues and ancillary revenues have a positive effect on the net profit of airline companies. In addition, the study found that aviation ancillary revenues provide an important resource for airline companies; furthermore, two US companies are among the top three companies with the highest revenues in the world in terms of cargo and ancillary revenues; also showed that Turkish Airlines' ancillary revenues are lower than those of these two US companies. On the other hand, the study showed that the contribution of Turkish Airlines cargo revenues to net profit is much higher than the other two companies.

The Covid-19 pandemic has created a disadvantaged student population due to the sudden obligation for distance learning. Poor performance of online educational tools, risk of transmission and staying at home cause stress and anxiety in students. This research examines the effects of usability and accessibility of the online learning system on students’ anxiety in presence of students’ perceived social support as well as students’ perceived optimistic/pessimistic life orientation. The survey instrument prepared for this purpose includes questions about the online learning system used, Covid-19 anxiety, life orientation and perceived social support. Web-based questionnaires were collected from 5,682 students from different universities and the data was analyzed for the role of social support and life orientation on anxiety caused by stress born of distance learning. Findings show that accessibility has a negative effect on anxiety while the effect of perceived social support on access problems could not be ascertained. It was determined that the optimism dimension had a moderating effect on students’ anxiety and the pessimism dimension had a mediating effect. The research results are consistent with the literature.

This paper examines the concept of symbiosis in Islamic history as developed by Schlomo Dov Goitein, the 20th-century Jewish German scholar in the area of Jewish and Arabic studies, and discusses its application to the identity sourcing of Prophet Muhammad in particular. The aim of the study is to review the historical outline briefly on the background and formation of “symbiosis” preceding and in the aftermath of Goitein’s conceptualization and context, following a qualitative research approach with an intertextual criticism to his references and discussing their possible philological aspects in his mindset. The study found that, while the Islamic historical sources presented the relations between Jews and Muslims in the Madina period of Islam as negative, in Goitein’s works, the Jewish perception of early Islamic history is positively grounded on a mid-eight century Jewish messianic-apocalyptical text, namely, The Secrets of Rabbi Simon ben Yohai as traditionally understood in Judaism for describing Ishmaelites as the savior of Jews from Christian oppression.  This finding seems to be in explicit contradistinction to the concept of innovative “creative symbiosis” with subversion of historical experience.

Cash(liquidity) management is at the heart of a firm’s financial management. It is a silver lining between the bankruptcy and the success story of a company. Therefore, this study intends to contribute some insights into cash management practices and how firms can use them to achieve sound financial performance. This study provides a comprehensive literature review on existing theories and cash management practices that are useful in decision making. After the analysis of the available literature, the study highlights important theories including trade-off theory (TOT), transaction model, precautionary measures, financial hierarchy, and cash flow theory. Furthermore, management practices such as stochastic cash management model, speeding up cash collections, centralization & decentralization of management, asset portfolio diversification, and cash disbursement are discussed.  The study suggests that a sound financial performance can be achieved through a hybrid approach and through adaptation and embracing innovations in cash management systems.