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Bearing performance characteristics, such as stiffness and load capacity, are related to the viscosity of the fluid circulating through the gap. Nanoparticle additives in lubricant are one way to enhance of the viscosity. This study aims to investigate the effect of nanoparticle additives on the thermohydrodynamic performance of journal bearing with different bearing parameters.

The temperature distribution is modeled using a three-dimensional energy equation. The velocity components are calculated on the pressure distribution governed by Dowson’s equation. Moreover, the heat transfer between the journal and lubricant is modeled with Fourier heat conduction equation. On the other hand, the viscosity equation is derived for Al₂O₃ nanoparticles as a function of the volume ratio and the temperature. An algorithm based on the finite difference method is developed, and a serial simulation is performed for different parameters and different volume ratio of nanoparticle.

With the increase in the nanoparticle volume ratio, the maximum temperature decreases for the lower clearance values, but the addition of the nanoparticle influence on the maximum temperature reverses when the clearance grows up. The nanoparticle additives increase further the maximum temperature for higher values of L/D ratios. Moreover, the effects of the nanoparticle additives on the pressure are stronger at high eccentricity ratios for all bearing parameters.

This paper provides valuable design parameters for journal bearing with lubricant containing the nanoparticle additives.

This paper aims to determine the knowledge and attitudes of the physicians regarding human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), to emphasize that these patients exist and they will exist in the future and to raise awareness so as to prevent that their rights to treatment are revoked.

The survey was conducted via a link sent through an online system. Random physicians from 81 cities of the country were invited to the survey. The survey has 41 questions regarding knowledge and attitudes in total, including epidemiological information such as age, gender and title.

A total of 3,107 physicians has voluntarily participated in the study. In total, 2,195 (70.7%) are internal physicians and 912 (29.3%) are surgical physicians among the participant physicians. In total, 1,452 (46.7%) of the participants are specialist physicians, 608 (19.6%) of the participants are practising physician and the rest of it is physician assistants, academicians and dentists, respectively.

In this study, it has been found out that the physicians have a lack of knowledge on HIV/AIDS and they adopt a discriminatory attitude towards HIV-positive persons. HIV-positive patients who are exposed to discrimination and scared of being uncovered refrain from applying to hospitals for treatment, which puts public health into jeopardy due to the high viral load and these patients are faced with difficulties in coping with both medical and emotional load of the disease.

This study investigates the effect of corporate governance mechanisms and country-level factors on the extent of Internet Financial Reporting (IFR). We used a sample of 106 listed firms from five African countries. A financial reporting disclosure index was used to compute the aggregate IFR scores, which are made up of two components: content and presentation. Our results indicate that IFR relates to board size, firm size, country-level governance, economic development and index return. These results evidence the predominance of country-level factors over firm-specific factors in explaining the extent of IFR in Africa. It also shows that corporate governance mechanisms via board practices are insufficient to explain IFR in Africa. By further extending our analysis into the two components of IFR, we find that factors affecting the content and presentation dimensions are different. This study is among the first to investigate the extent of IFR in several African countries and adds to the existing evidence that has mainly focussed on firm-specific factors.

The purpose of this paper is to investigate the impact of polychronicity on frontline employees’ (FLEs) service recovery performance, perceived role overload, and work stress in a hotel work setting.

In this survey, a total number of 267 usable questionnaires were personally retrieved from a sample of full-time FLEs in the research location. The hypothesized relationships were tested using hierarchical regression analysis.

Results based on hierarchical regression analysis reveal that polychronicity had positive impact on service recovery performance and negative impact on role overload and work stress. Significantly, while education was found to be positively related to service recovery performance, on the other hand, age, education, and job tenure were found to be negatively related to role overload and work stress.

This paper provides implications for managers in terms of minimizing FLEs role overload and work stress and maximizing their service recovery performance. Also, this study provides useful guidelines to implement effective management practices and improve organizational outcomes within a hotel work setting.

Theoretically, the current study by examining the untried effects and relationships such as the effect of polychronicity on FLEs’ service recovery performance and work stress lends further contribution to the tourism and hospitality management literature.

The purpose of this paper is to define the outcomes of bullying at work. In that sense, the study tries to define the effect of bullying at work on work alienation and the roles of political behavior perception and organizational alienation in this effect.

The study collects data from lecturers from a university in Turkey by using questionnaires. Structural equation model is used to test hypotheses.

The findings of the study show that political behavior perception has a mediating role over the effect of bullying at work on work alienation, and also that organizational alienation has a mediating role over the effect of political behavior perception on work alienation.

The study confirms that perception of bullying at work is determinant on the level of work alienation; thus, it is important to minimize bullying perception. This study shows both researchers and organizations that further potential vital problems to arise as a result of bullying will diminish once bullying at work is decreased.

The research tries to define the consecutives of bullying within a multi-level point of view. Additionally, as per the authors’ knowledge, there are no other studies in the literature that handle the related variables altogether.

The purpose of this study is to examine the effect of Board of Directors Effectiveness (BODE) on the performance of Malaysian Takaful companies licensed by the Central Bank of Malaysia. In addition, the study investigates the moderating effect of Shariah Committee Quality (SCQ) on the relationship between BODE and companies’ performance.

This study uses a sample of 11 Malaysian Takaful companies during the period of 2010-2017. While BDE and SCQ are measured using indices, performance is proxied using ROA and ROE. A panel fixed effect regression analysis is used to test the impact of the BDE on the financial performance of Malaysian Takaful companies and the moderator role of SCQ.

The main finding of this study shows a positive association between BDE and performance. More specifically, boards with a high presence of independent, Muslim and female directors positively contribute to the performance of Malaysian Takaful companies. Another interesting finding is related to the positive moderating effect of SCQ on the relationship between BDE and performance. This result indicates that a high level of SCQ combined with a high level of board effectiveness improve performance.

The finding is of great importance to stakeholders and policymakers to improve their board effectiveness and the quality of the Shariah committee to reduce agency costs and to improve the performance of Malaysian Takaful companies.

This study adds to the prior literature by investigating for the first time the relationship between BDE and performance and the interaction effect of SCQ on the performance of Malaysian Takaful companies.

The purpose of this study is to develop a non-enzymatic based glucose-sensing platform composed of Bodipy-BBV dual system which can be monitored by a photodetector under the blue LED excitation.

The sensor has been developed from a dual system including a fluorescent dye, an aldehyde derivative of boron dipyrromethene (Bodipy) and a quencher, orto-boronic acid linked viologen (o-BBV) where their combination resulted in a ratiometric fluorescence quenching in ethanol: PBS (1:1, pH:7.4) solution under UV light excitation. By glucose addition, o-BBV has been released from the Bodipy and binded to cis-diol groups of glucose, thereby fluorescence emission of Bodipy has been regained. Furthermore, a setup consisting of a light emitting diode (LED) and a photodiode (PD) was used to prove electrical detection of glucose without the need for expensive and bulky optical equipment, enabling the development of a miniaturized and low-cost glucose-sensing platform.

The fluorescence intensity of the Bodipy derivative in the solution (2 × 10⁻⁶ M) was diminished by 93% in the presence of o-BBV solution (5 × 10⁻³ M). Upon the glucose addition, 81% of the Bodipy fluorescence intensity has been recovered after introduction of 30 mM of glucose, where the ratio of o-BBV/Bodipy was 35:1. A linear response between 10 and 30 mM glucose concentration was obtained, which covers the biologically significant range. A high correlation between the photodiode current and Bodipy fluorescence intensity was achieved.

Even though Bodipy molecules are known with their superior optical properties and applied to the fluorescence-based detection of glucose, to the best of the authors’ knowledge, no work has been reported on Bodipy-BBV dual system to detect glucose molecules as a non-enzymatic based method. This design enables the dye and the quencher to independently coexist in the solution, allowing for tuning of their individual concentrations to optimize the glucose sensitivity. Furthermore, an electrical light detection scheme consisting of a LED and a photodiode has been implemented to eliminate the bulky optical equipment from the measurement setup and further this work for the development of a compact and inexpensive sensor. The results presented here demonstrate the feasibility of this system for the development of a novel glucose sensor.

This study aims to discover the general trends, the structural characteristics of the knowledge base, and developments in the field of internationalization of higher education (IHE) in Turkey. In this respect, the studies published in journals indexed by SSCI, SCI-Expanded, ESCI, and AHCI in Web of Science (WoS) between January 1, 1975, and November 20, 2021, were analyzed. The dataset included 260 articles. We administered descriptive analysis reflecting the topographical features and the dynamics of the related literature through Excel and the WoS analysis tools. We conducted bibliometric analyses to shed light on the current view of the literature and reveal the intellectual structure of the knowledge base and topical foci. The volume of the research in the field of IHE in Turkey and their yearly distribution suggests that this area of research is still in its infancy; however, there has been a rapid growth in the number of publications recently. Author co-citation analysis reveals four distinct schools of thought labeled as “Higher Education Policy Studies in EU,” “Global Socio-politics and Economics of IHE,” “Socio-cultural and Psychological Dimensions of Internationalization” and “Language Studies.” Finally, topical foci in the knowledge base emerged as “International Student Mobility,” “Psychological and Cultural Adaptation of International Students,” “Higher Education Policy Reforms,” “International Staff Mobility” and “Migration Related Issues.” The results are discussed with related review studies and suggestions for future research are provided.

Construction managers must focus on effective job design to develop and harness employee talent and achieve organizational goals. Because psychological needs and key motivators vary by career stage, a differentiated employee value proposition is crucial for a firm’s retention strategy. This study aims to examine how job crafting (JC) affects job embeddedness (JE) at different career stages.

In this investigation, a quantitative methodology was used. In total, 272 construction industry professionals from 25 construction firms in Abu Dhabi, United Arab Emirates, provided the data. Through the use of structural equation modeling, hypotheses were evaluated.

The results show that JC enhances construction professionals’ JE (β = 0.60, p < 0.000). Moreover, the relationship between JC and JE is moderated by career stages. The impact of JC on JE is greater among longer tenured (late-career stages, β = 0.61, p < 0.000) than shorter tenured construction professionals (early-career stages, β = 0.60, p < 0.000 and mid-career stages, β = 0.58, p < 0.000).

Limited research shows how JC can improve JE. At the time of this research, there was no published work on JC and JE relationship in the construction industry. This research found that JC has a positive impact on JE and JC behavior applies at both individual and team levels. This could imply that construction professionals with longer organizational tenure are more likely to challenge the status quo and identify problems or opportunities for improvement, hence contributes to JE theory.

Environmental and operational restrictions increasingly drive modern aircraft design due to the growing impact of global warming on the ecology. Regulations and industrial measures are being introduced to make air traffic greener, including restrictions and environmental targets for aircraft design that increase aerodynamic efficiency. This study aims to maximize aerodynamic efficiency by identifying optimal values for sweep angle, taper ratio, twist angle and wing incidence angle parameters in wing design while keeping wing area and span constant.

Finding optimal wing values by using gradient-based and evolutionary algorithm methods is very time-consuming. Therefore, an artificial neural network-based surrogate model was developed. Computational fluid dynamics (CFD) analyses were carried out by using Reynolds-averaged Navier–Stokes equations to create a properly trained data set using a feedforward neural network.

The results showed how a wing could be optimized by using a CFD-based surrogate model. The two optimum results obtained resulted in increases of 10.7397% and 10.65% in the aerodynamic efficiency of the baseline design ONERA M6 wing.

The originality of this study lies in the combination of sweep angle, taper ratio, twist angle and wing incidence angle within the scope of wing optimization calculations.