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The authors performed a systematic review and meta-analysis of all published randomized controlled trials with the aim to determine and quantify the anti-hyperglycemic effects of glutamine (Gln) in acute and chronic clinical settings.

The authors conducted a comprehensive search of all randomized clinical trials performed up to December 2018, to identify those investigating the impact of Gln supplementation on fasting blood sugar (FBS), insulin levels and homeostatic model assessment-insulin resistance (HOMA-IR) via ISI Web of Science, Cochrane library PubMed and SCOPUS databases. A meta-analysis of eligible studies was conducted using random effects model to estimate the pooled effect size. Fractional polynomial modeling was used to explore the dose–response relationships between Gln supplementation and diabetic indices.

The results of the present meta-analysis suggest that of Gln supplementation had a significant effect on FBS (weighted mean difference (WMD): –2.868 mg/dl, 95 per cent CI: –5.467, –0.269, p = 0.031). However, the authors failed to observe that Gln supplementation affected insulin levels (WMD: 1.06 units, 95 per cent CI: –1.13, 3.26, p = 0.34) and HOMA-IR (WMD: 0.001 units, 95 per cent CI: –2.031, 2.029, p = 0.999). Subgroup analyses showed that the highest decrease in FBS levels was observed when the duration of intervention was less than two weeks (WMD: –4.064 mg/dl, 95 per cent CI: –7.428, –0.700, p = 0.01) and when Gln was applied via infusion (WMD: –5.334 mg/dl, 95 per cent CI: –10.48, 0.17, p = 0.04).

The results from this meta-analysis show that Gln supplementation did not have a significant effect on insulin levels and HOMA-IR. However, it did significantly reduce the levels of FBS, obtaining a higher effect when the duration of the intervention period was less than two weeks.

The aims of this study is to analyze failure of two types of high‐strength low‐alloy (HSLA) steels which are used in wheel bolts 10.9 grade, boron steel and chromium‐molybdenum steel, before and after heat treatment.

The optimum heat treatment to obtain the best tensile behavior was determined and Charpy impact and Rockwell hardness tests were performed on the two steel types before and after the optimum heat treating.

Fractographic studies show a ductile fracture for heat‐treated boron steel while indicate a semi‐brittle fracture for heat‐treated chromium‐molybdenum steel. Formation of a small boron carbide amount during heat treating of boron steel results in increment the bolt's tensile strength while the ductility did not changed significantly. In the other hand, formation of chromium and molybdenum carbides during heat treating of chromium‐molybdenum steel increased the bolt's tensile strength with a considerable reduction in the final ductility.

This paper evaluates failure analysis of HSLA wheel bolt steels and compares their microstructure before and after the loading regime.

In this study, self-cleaning properties are introduced to acrylic carpet through a simple method of spraying nano titanium dioxide (NTO) onto the carpet surface. A cross-linkable polysiloxane (PS) softener is also applied to enhance the washing durability, self-cleaning properties and handle softness. The self-cleaning properties of the acrylic carpet are investigated by using Solophenyl Red GBL as a synthetic dye and black mulberry as a natural dye to stain the carpet. The PS and NTO concentrations and the type of ultra violet (UV) irradiation are designed based on the statistical approach of a central composite design (CCD). UV irradiation is used under the form of daylight for 16 h, UV-A (400 W) for 1 h and UV-C (20 W) for 3 h. The photocatalytic decolorization values (ΔE*) of the treated carpet are measured and the optimized models are presented. The PS is capable of stabilizing the NTO particles on the surface of the acrylic carpet and helps to increase the washing durability. Also, the NTO particles can effectively photodegrade both the Solophenyl Red GBL and black mulberry dyes which act as the two coloring stains.

This study addresses the prevailing complexities and limitations in estimating and managing construction overhead costs (COCs) in the existing literature, with the purpose of enhancing the accuracy of cost performance indicators in construction project management.

An innovative approach is proposed, employing the activity-based costing (ABC) accounting method combined with building information modelling (BIM) to assign real overhead costs to project activities. This study, distinguished by its incorporation of a real case study, focuses on an administrative building with a four-story concrete structure. It establishes an automated method for evaluating project cost performance through the detailed analysis of earned value management (EVM) cost indicators derived from ABC results and BIM data.

The results show that the ABC integration improves the accuracy of cost performance indicators by over 9%, revealing the project's true cost index for the first time and demonstrating the substantial value of the approach in construction engineering and management.

The current study highlights a notable gap in the existing literature, addressing the challenges in onsite overhead cost estimation and offering a solution that incorporates the state-of-the-art techniques.

The proposed method has significant implications for project managers and practitioners, enabling better-informed decisions based on precise cost data, ultimately leading to enhanced project outcomes.

This research uniquely combines ABC and BIM, presenting a pioneering solution for the accurate estimation and management of COCs in construction projects, adding significant value to the current body of knowledge in this field.

This study aims to investigate heat and mass transfer in a one-row heat exchanger. The required equations are obtained based on two-dimensional model analysis in a cell of the heat exchanger. By using finite difference approach, the obtained equations are solved to determine distribution of temperature and the efficiency of the heat exchanger in the case of partially wet surface. In this research, Lewis Number as unity and water vapor saturation as parabolic are assumed. Obtained results show that increase in thermal conductivity fin leads to decreasing thermal resistance; therefore, temperature changes in radial from center to out of fin are reduced and efficiency of fin increases.

In this regard, fin material plays a significant role in fin efficiency. Changes in airflow also result in an efficiency increase by temperature and relative humidity, and efficiency is decreased by airflow velocity increase, and these changes are almost linear. Moreover, the fins with more wet surface are more sensitive to changes in fin dimensions and air flow characteristics, and it is a result of conjugate heat transfer mechanism, in which latent heat transfer in the fins with more wet surface has a significant role.

Thermal property and geometry of the fin under wet conditions play a more important role than the fin under dry conditions. Changes in airflow result in an efficiency increase by temperature and relative humidity, and efficiency is decreased by airflow velocity increase, and these changes are almost linear. Fins with more wet surface are more sensitive to changes in fin dimensions and air flow characteristics.

Effects of the temperature of water supply and mass flow rate were considered in the study. The results had good agreement with actual data.

This paper aims to investigate the optimization of window and shading designs to reduce the building energy consumption of a standard office room while improving occupants' comfort in Tehran and Auckland.

The NSGA-II algorithm, as a multi-objective optimization method, is applied in this study. First, a comparison of the effects of each variable on all objectives in both cities is conducted. Afterwards, the optimal solutions and the most undesirable scenarios for each city are presented for architects and decision-makers to select or avoid.

The results indicate that, in both cities, the number of slats and their distance from the wall are the most influential variables for shading configurations. Additionally, occupants' thermal comfort in Auckland is much better than in Tehran, while the latter city can receive more daylight. Furthermore, the annual energy use in Tehran can be significantly reduced by using a proper shading device and window-to-wall ratio (WWR), while building energy consumption, especially heating, is negligible in Auckland.

To the best of the authors' knowledge, this is the first study that compares the differences in window and shading design between two cities, Tehran and Auckland, with similar latitudes but located in different hemispheres. The outcomes of this study can benefit two groups: firstly, architects and decision-makers can choose an appropriate WWR and shading to enhance building energy efficiency and occupants' comfort. Secondly, researchers who want to study window and shading systems can implement this approach for different climates.

This study aims to empirically investigate the role of organizational culture and climate in supporting intellectual capital (IC) management systems. Specifically, it seeks to investigate the relationship between organizational characteristics (culture and climate) and IC management systems in the Middle East (Iran and Lebanon) and Canada.

Data were gathered via a survey instrument and statistical analysis was used to test for significance between dependent and independent variables. Then a two‐stage hierarchical multiple regression was used to test for the nature and effects of country of origin as a moderating variable.

The findings suggest that both culture and climate play significant roles in developing management systems for IC. In addition, for country, when organizational climate improves, Middle Eastern respondents perceived an even greater improvement in IC management systems compared to their Canadian counterparts.

There is limited research that has been undertaken to compare developed and developing countries with regard to the influence of organizational characteristics on IC management systems. This research is timely given the recent publication of the Arab Human Development Report and the Arab Knowledge Report. This study provides insight into the ability of organizations in the Middle East to develop a knowledge base and reduce the knowledge gap between the Arab world and countries currently classified as knowledge intensive.

The chapter explored integrating smart construction techniques in achieving stealth construction objectives, emphasising the development of building cross-sections, visibility management, energy transmission optimisation, and countermeasure implementation. It delved into the multifaceted aspects of smart construction towards achieving stealth construction goals, including environmental protection, enhanced construction safety, accelerated construction duration, cost-effectiveness, and aesthetic considerations. Furthermore, the chapter underscores the importance of leveraging innovative approaches and advanced technologies to meet the evolving demands of stealth construction projects and pave the way for sustainable, safe, and aesthetically pleasing built environments.

The purpose of this study is to investigate empirically what affects Global Reporting Initiative (GRI)-based sustainability reporting and its relationship with firm performance in the aviation industry between 2006 and 2015.

The authors derived data from the GRI Sustainability Disclosure Database and Thomson Reuters EIKON; from the former, they downloaded GRI-based reports, and from the latter, they obtained financial data. The authors performed four-level analysis – report existence, report count, application level of report and firm performance –using various regression models (i.e. logistic regression, Poisson regression, ordered logistic regression and ordinary least squares regression).

First, the authors based the analysis on the existence of GRI-based sustainability reports, which showed that firm size and leverage are positively associated with sustainability reporting. Contrary to expectations, ownership was negatively associated. Furthermore, free cash flow per share, growth and profitability do not have significant effects on sustainability reporting, in contrast to expectations. Subsequent analysis was based on report count (number of total published reports within the examination period) and application levels of reports. Compared to the preceding analysis, there were no notable surprises. In addition, we found evidence that growth is negatively associated with application levels of reports (partially supported). Thus, report existence, report count and application level results largely confirm each other. Finally, the authors tested the effect of sustainability reporting on firm performance, which did not produce significant results. Thus, in the aviation industry, sustainability reporting does not play a significant role in enhancing firm performance.

First, the findings show that larger and highly leveraged aviation firms can reduce agency and legitimacy costs through sustainability reporting. Surprisingly, the same assumption did not hold for ownership structure as the firms with diffused ownership base tend not to publish sustainability reports. Thus, boards are advised to establish and improve monitoring mechanisms in these types of firms. Second, although the number of aviation companies publishing separate sustainability reports has increased significantly over the years, almost half of the companies are not still producing sustainability reports. Hence, if the aviation industry believes the merits of engaging in sustainability issues and sincerely desires to enhance its sustainability reporting practices, the authors can suggest the following initiatives. Boards might encourage companies to incorporate sustainability issues into company operations by assigning the necessary financial and human resources. The boards might also establish a separate sustainability committee or department, which could focus on sustainability issues and reporting practices. Regulatory bodies could also encourage aviation companies to act in a socially and environmentally responsible manner by proposing legal requirements and providing guidance.

Relevant civil organisations and environmental activists might undertake more active roles to enhance awareness of sustainability issues in the aviation industry.

Most of the prior studies did not focus on standalone GRI-based sustainability reports, and they were conducted on limited samples and not the aviation industry in particular. This study aims to fill these gaps empirically by establishing testable hypotheses and attempting to demonstrate the validity of theoretical relationships in a wide range of data and among aviation companies worldwide. In this sense, this study is unique in what it undertakes. This study also tests whether sustainability reporting impacts firm value in the aviation industry which, to the best of the authors’ knowledge, has not been examined in prior studies to this extent.

Different studies have analyzed the relationship between organizational learning (OL) and innovation performance (IP). However, the question of how innovation culture (IC) affects the relationship between OL and IP remains unexplored. This study aims to examine the impact of IC on the relationship between OL and various dimensions of IP, including product, process and objective innovation.

A research model was developed and performed based on the relevant literature in the field of OL, IC and IP. The hypotheses are tested with the data collected from companies operating in an intensive knowledge-based industry.

Based on the results of 625 questionnaires completed by pharmaceutical companies, OL activities and IC can result in product and process innovation. However, this relationship was not supported for the objective innovation. Furthermore, in terms of the moderating role of IC in the relationship between OL and IP dimensions, the results were significant.

The findings help to gain a better understanding of how organizational commitment by creating a culture for innovation can help to maximize the benefits of continuous OL in product and process innovation.

Considering the three aspects of IP, it is the first survey of the contribution of OL in firms’ IP with considering the moderating role of IC. The proposed model would enrich the relevant literature and provide us with better understanding how OL contributes to the IP.