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The purpose of the study is to evaluate mobile apps developed to prevent food waste from the perspective of responsible production and consumption.

The study employs qualitative methods, and the dataset consists of the 1,382 content and online reviews and comments for 11 mobile apps in addition to 30 in-depth interviews conducted with consumers and restaurant managers/owners using the apps.

Mobile apps are proving to be popular with people, inviting users to fight food waste in a sustainable and responsible way. While users' main motivations for becoming food waste fighters are responsibility, positive emotions and economic sensitivity, restaurants' motivations are different, such as social responsibility, innovative business models, attracting new customers and cost orientation.

Creating digital value and contributing significantly to sustainability in the food industry, mobile apps offer different opportunities to the market. By supporting and encouraging the use of these apps, businesses can reduce food waste, prevent financial losses and offer consumers more choice and variety.

The present study aims to address this lack of empirical research based on a holistic perspective by providing a multidimensional assessment. Such an approach should contribute to a thorough understanding of the motivations that drive users and restaurants to become food waste fighters.

Diabetes is one of the health problems of increasing importance owing to the increase in its incidence and the problems it causes, and it is closely related to nutrition. This study aims to determine the relationship between the dietary inflammatory index (DII) scores of individuals with type 2 diabetes, depression, anxiety and quality of life.

In this cross-sectional study, 158 individuals with type 2 diabetes who applied to a nutrition and diet outpatient clinic of a private hospital in Istanbul were included. Their depression status was evaluated using the Beck Depression Inventory; their anxiety status was evaluated using the Beck Anxiety Inventory; and their quality of life was evaluated using the Short Form 36 Quality of Life scale. One-way ANOVA test was used to define the difference between groups. All test results were evaluated at a significance level of 0.05.

There was no significant relationship between DII scores, depression (p = 0.814) and anxiety (p = 0.817). However, a significant decrease was observed in the scores of the quality of life criterion in the groups with high depression and anxiety scores (p < 0.05). In addition, participants with high anxiety states had higher HbA1c levels (p = 0.043).

Individuals in this sample with no known psychiatric diagnosis or treatment history demonstrated a significant relationship between depression and anxiety scores and quality of life.

The selection of the contractor, as a main participant of a construction project, is the most important and challenging decision process for a client. The purpose of this paper is to propose a multi-agent systems (MAS)-based contractor pre-qualification (CP) model for the construction sector in the frame of the tender management system.

The meta-classification and analysis study of the existing literature on CP, contractor selection and criteria weighting issues, which examines the current and important CP criteria, other than price, is introduced structurally. A quantitative survey, which is carried out to estimate initial weightings of the identified criteria, is overviewed. MAS are used to model the pre-qualification process and workflows are shown in Petri nets formalism. A user-friendly prototype program is created in order to simulate the tendering process. In addition, a real case regarding the construction work in Turkey is analyzed.

There is a lack of non-human-driven solutions and automation in CP and in the selection problem. The proposed model simulates the pre-qualification process and provides consistent results.

The meta-classification study consists of only peer-reviewed papers between 1992 and 2013 and the quantitative survey initiates the perspectives of the actors of Turkish construction sector. Only the traditional project delivery method is selected for the proposed model, that is other delivery methods such as design/build, project management, etc., are not considered. Open, selective limited and negotiated tendering processes are examined in the study and the direct supply is not considered in the scope.

The implications will help to provide an objective CP and selection process and to prevent the delays, costs and other troubles, which are caused by the false selection of a contractor.

Automation and simulation in the pre-qualification and the selection of the contractor with a non-human-driven intelligent solution ease the decision processes of clients in terms of cost, time and quality.

Starting in the 1980s, financial liberalization and technological developments have enabled individual investors to participate in financial markets and carry out easy transactions. With these developments, academics began to wonder how the individual investors decide to invest and what factors affect these decisions.

According to traditional finance theory, it is suggested that markets are efficient and investors show rational behaviors in their financial purchasing decisions. However, in many studies conducted in recent years, it was determined that investors included emotional elements as well as rational elements in their decision-making process and therefore exhibited irrational behaviors by believing rumors instead of real information. It is thought that many factors such as personal characteristics, psychological factors, demographic and socio-economic factors play a role in the behavior of investors in purchasing a financial product.

In this study, the importance of herd behavior, which is one of the psychological factors that play a very important role in financial markets, on financial product purchasing process is examined in the light of the behavioral finance theory. It is thought that information included in the study will be useful for researchers who want to study herd behavior and for those who are interested in the subject.

Capital markets thrive on information, and the information revolution has transformed these markets all over the world. Investors can now keep track of the movements of capital markets in real-time and they react to the flow of information from around the world. One of the concerns of stock market investors is whether the markets operate efficiently, independently, and with sound fundamentals. However, real market movements tend to exhibit a link as is evident from recent market movements across the world.

The assessment of interdependence between stock markets is an important aspect of international portfolio management. The aim of this chapter is to examine the shock and volatility spillover between the Standard and Poor’s 500 (S&P500) index from the United States (US) Stock Exchange and the Istanbul Stock Exchange 100 (BIST100) index from the Stock Exchange Istanbul.

S&P500 index, which is the most important index representing US markets, and BIST100 index, which is the index representing the Turkish market, were used as variables in this study. In the analysis, the causality in variance test was applied to determine the volatility spillover between these two markets. Later, multivariate GARCH (MGARCH) models were used to measure the volatility spillover in the markets. VAR(1)-GARCH (1,1)-Diagonal BEKK model was applied to the daily data to determine the shock and volatility spillover in the markets.

As a result of the variance causality test, it was found that there is a bi-directional volatility spillover between S&P500 index and BIST100 index. When the return spillover between the markets is examined, a one-way spillover from the S&P500 index to the BIST100 index emerged. Diagonal BEKK model results show that each market is affected by its own news (unexpected shocks) and volatility. Furthermore, the volatility is persistent for both markets. These findings demonstrate that the US market and the Turkish market interact with each other.

Nowadays, the most important challenge in mechanical engineering, power engineering and electronics is a development of effective cooling systems for heat-generating units. Taking into account this challenge, this study aims to deal with computational investigation of thermogravitational energy transport of pseudoplastic nanoliquid in an electronic chamber with a periodic thermally producing unit placed on the bottom heat-conducting wall of finite thickness under an influence of isothermal cooling from vertical side walls.

The control equations formulated using the Boussinesq approach, Ostwald–de Waele power law and single-phase nanofluid model with experimentally based correlations of Guo et al. for nanofluid dynamic viscosity and Jang and Choi for nanofluid thermal conductivity have been worked out by the in-house computational procedure using the finite difference technique. The impact of the Rayleigh number, nanoadditives concentration, frequency of the periodic heat generation from the local element and thickness of the bottom solid substrate on nanoliquid circulation and energy transport has been studied.

It has been found that a raise of the nanoadditives concentration intensifies the cooling of the heat-generating element, while a growth of the heat-generation frequency allows reducing the amplitude of the heater temperature.

Mathematical modeling of a pseudoplastic nanomaterial thermogravitational energy transport in an electronic cabinet with a periodic thermally generating unit, a heat-conducting substrate and isothermal cooling vertical surfaces to identify the possibility of intensifying heat removal from a heated surface.

Introduction – In today’s intense competitive environment, businesses that want to have a sustainable competitive advantage must put the customer at the centre of all their activities and create customer loyalty by offering products and services that will provide customer satisfaction. One of the key elements of ensuring customer satisfaction is the effective handling of customer complaints, which is defined as the customers expressing their dissatisfaction with unmet expectations and unsatisfied needs verbally or in writing. The concept of a complaint as a response of customers’ dissatisfaction with the products and services they experience is an invaluable feedback mechanism for businesses to resolve issues relating to their products and services.

Aim – The aim of this chapter is to emphasise the importance of the concept of complaint as an important part of customer relations management and an effective marketing tool for the tourism sector. As a service sub-sector, the simultaneous production and consumption of services in the tourism sector ensures customer satisfaction more than concrete products, due to their inseparable nature. For this reason, handling, evaluating and finalising customer complaints has an important function and value in providing the necessary information for tourism enterprises to become aware of their deficiencies and mistakes. Complaint management has started to play an even more critical role for the tourism industry in preventing customer losses due to dissatisfaction, especially considering the shrinkage in demand in the sector due to the COVID-19 pandemic.

Method – Firstly the concept of complaint and the importance of complaints for businesses were explained, customer complaint behaviour and the factors affecting this behaviour were examined in detail, the concept of online complaint was mentioned and the subject was evaluated in terms of tourism businesses.

Results – While the effective management and resolution of complaints should be seen as a goal by every tourism business, it is vital that they understand customer complaint behaviours, the factors affecting this behaviour and how complaints should be managed in a way that will result in favour of the business.

Conclusion – A complaint management process that enables customers to easily report their complaints to businesses and produces solutions as soon as possible will positively affect customer satisfaction. In this context, in order to reduce the negative effects on tourism enterprises, especially through the pandemic, business need to have clear and easy-to-access procedures, provide a quick response, show reliability and consistency in providing a solution, keeping the complainant informed of progress, have employees who can communicate with empathy and courtesy, have enough employees to deal with the situation, and adopt proactive approaches to prevent complaints rather than reducing the volume of complaints.

Originality/Value – This research contributes to the literature in terms of complaining behaviour, examining the factors affecting this behaviour and emphasising the importance of the concept of complaints in the tourism sector. In addition, the research is important in terms of examining the contributions of an effective complaint management system in reducing the negative effects of the COVID-19 pandemic on the tourism sector, which is one of the sectors mostly affected on a global scale.

Introduction – Increases in prices of commodity markets may be associated with increased volatility in financial markets. That is why analysing time-varying co-movements of commodity prices can be of great importance for investors who take into consideration optimal asset allocation.

Purpose – The aim of this study is to investigate the volatility spillover from oil to precious metals under high-volatility and low-volatility regimes.

Methodology – The data covered daily closing prices of assets such as oil, palladium, and platinum for the period January 2010–December 2018. GARCH models were analysed in order to determine the most appropriate volatility structure, and it was determined that GARCH (1,1) model was the most suitable model for all commodities. Markov Switching model was used to analyse the volatility spillover from oil to precious metals.

Findings – According to the analyses, the results showed that there were volatility spillovers from oil to palladium and platinum in low-volatility regimes and from oil to platinum in high-volatility regimes. On the other hand, there was no volatility spillover from oil to palladium in high-volatility regimes. Investing into oil and palladium in the same portfolio can provide diversification benefits for investors in high-volatility regimes. On the other hand, investing into oil and palladium in the same portfolio may not provide diversification benefits for investors in low-volatility regimes. The findings of the analyses can be beneficial for investors, market participants, and portfolio managers to make an accurate portfolio management.