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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.

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.