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The potential implications of the three-dimensional printing (3DP) technology are growing enormously in the various health-care sectors, including surgical planning, manufacturing of patient-specific implants and developing anatomical models. Although a wide range of thermoplastic polymers are available as 3DP feedstock, yet obtaining biocompatible and structurally integrated biomedical devices is still challenging owing to various technical issues.

Polyether ether ketone (PEEK) is an organic and biocompatible compound material that is recently being used to fabricate complex design geometries and patient-specific implants through 3DP. However, the thermal and rheological features of PEEK make it difficult to process through the 3DP technologies, for instance, fused filament fabrication. The present review paper presents a state-of-the-art literature review of the 3DP of PEEK for potential biomedical applications. In particular, a special emphasis has been given on the existing technical hurdles and possible technological and processing solutions for improving the printability of PEEK.

The reviewed literature highlighted that there exist numerous scientific and technical means which can be adopted for improving the quality features of the 3D-printed PEEK-based biomedical structures. The discussed technological innovations will help the 3DP system to enhance the layer adhesion strength, structural stability, as well as enable the printing of high-performance thermoplastics.

The content of the present manuscript will motivate young scholars and senior scientists to work in exploring high-performance thermoplastics for 3DP applications.

Through a theoretical lens of psychological ownership, this study aims to investigate how technology mindfulness may stimulate metaverse tourism users’ feelings of individual psychological ownership, aesthetic value and conversational value, which in turn fosters intention to engage in prosocial behaviors.

The study used a scenario-based survey that allowed U.S.-based participants to create their own avatars and imagine using their avatars to explore heritage sites in the metaverse. Structural equality modeling was applied for data analysis.

The results from 357 valid responses indicate that technology mindfulness arouses tourists’ individual psychological ownership, aesthetic value, conversational value and prosocial behavioral intentions. The moderating role of biospheric value orientation on willingness to donate and intention to volunteer is investigated.

The research sheds light on the significance of technology mindfulness, conversational value and psychological ownership perspectives in the metaverse, which have been previously overlooked. The authors used a scenario-based survey for mental stimulation due to current metaverse technology limitations.

The study is one of the first to explore the possibility of encouraging prosocial behaviors using metaverse-facilitated technology. The research offers guidelines to engage hospitality and tourism customers in the metaverse that can blend their virtual experiences into the real world.

This study represents one of the pioneering efforts to gain an in-depth understanding of the application of metaverse in triggering prosocial behavior toward heritage sites, explained via a technology mindfulness-driven model with a psychological ownership perspective.

Drawing on the socially embedded model of thriving and the idiosyncrasy credit model of leadership, this study aims to develop a moderated mediation model to investigate the roles that are thriving at work and leader competency play in the link between leader humility and creative service performance (CSP) of hospitality frontline service employees (FSEs).

To test the moderated mediation model, the authors applied a time-lagged research design and collected multi-source data from locally owned, star-rated hotels headquartered in the capital city of Pakistan. The authors collected the multi-source data at three different points in time from employees and their respective supervisors (N = 52 managers and their 312 immediate employees).

The results denote that leader humility positively impacts CSP, thriving at work mediates this impact and leader competency not only moderates the connection between leader humility and thriving at work but also magnifies the indirect association between leader humility and CSP via thriving at work.

The moderated mediation framework based on the socially embedded model of thriving and the idiosyncrasy credit model of leadership will benefit future researchers and practitioners while exploring the impact of leader humility (LH) on FSEs’ CSP in the hospitality context.

The fundamental contribution of this study is developing and testing a research model that concentrates on the effects of leader humility on FSEs’ CSP. Moreover, by receiving support on the mediating role of thriving, this research further sheds light on how subordinates under the leader with humility demonstrate high CSP. In addition, the moderating role of leader competency found in this study further highlights that leader effectiveness depends on the degree to which employees perceive their leader as competent.

This paper aims to study the breather, lump-kink and interaction solutions of a (3 + 1)-dimensional generalized shallow water waves (GSWW) equation, which describes water waves propagating in the ocean or is used for simulating weather.

Hirota bilinear form and the direct method are used to construct breather and lump-kink solutions of the GSWW equation. The “rational-cosh-cos-type” test function is applied to obtain three kinds of interaction solutions.

The fusion and fission of the interaction solutions between a lump wave and a 1-kink soliton of the GSWW equation are studied. The dynamics of three kinds of interaction solutions between lump, kink and periodic waves are discussed graphically.

This paper studies the breather, lump-kink and interaction solutions of the GSWW equation by using various approaches and provides some phenomena that have not been studied.

Tuberous Sclerosis Complex (TSC) is associated with many learning, behavioural, neurodevelopmental and psychiatric difficulties. Over 90 per cent of those with TSC will have some of these concerns, yet typically no more than 20 per cent receive support and treatment. The purpose of this paper is to provide an overview of TSC-Associated Neuropsychiatric Disorders (TAND), explore barriers to identification and management of TAND, and propose possible next steps to improve assessment and treatment of TAND.

The paper combines a brief review of the multiple levels of TAND with a conceptual analysis of barriers and potential facilitators to assessment and intervention for TAND.

Results suggest that the perceived uniqueness of TAND leads to treatment paralysis for most healthcare professionals, thus explaining the assessment and treatment gap seen for TAND. This may in part be due to the multi-dimensionality of TAND, and in part due to lack of access to clear, useful and evidence-based resources for TAND.

Identification of natural TAND clusters through machine-based learning and data reduction methodologies may yield a manageable number of natural groups of TSC-related neuropsychiatric problems, for which a basic “toolkit” of evidence-based interventions could be developed.

Families and clinicians will benefit from a toolkit of tried and tested resources and evidence-based information to guide further investigation and management of TAND.

Even though individuals will have unique TAND profiles, there may be key natural TAND clusters – combinations of behaviours across multi-dimensional levels – that will simplify and improve access to further evaluation, treatment and neuroscientific research.

This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim is to provide an updated map of trends and gaps in this relevant research field. Several technologies and investigation methods are examined, thus giving an overview and analysis of the growing body of research.

Permutations of keywords, which concern materials, technologies and the accuracy of thermoplastic polymeric parts fabricated by AM, are used for a systematic search in peer-review databases. The selected articles are screened and ranked to identify those that are more relevant. A bibliometric analysis is performed based on investigated materials and applied technologies of published papers. Finally, each paper is categorised and discussed by considering the implemented research methods.

The interest in the accuracy of additively manufactured thermoplastics is increasing. The principal sources of inaccuracies are those shrinkages occurring during part solidification. The analysis of the research methods shows a predominance of empirical approaches. Due to the experimental context, those achievements have consequently limited applicability. Analytical and numerical models, which generally require huge computational costs when applied to complex products, are also numerous and are investigated in detail. Several articles deal with artificial intelligence tools and are gaining more and more attention.

The cross-technology survey on the accuracy issue highlights the common critical aspects of thermoplastics transformed by AM. An updated map of the recent research literature is achieved. The analysis shows the advantages and limitations of different research methods in this field, providing an overview of research trends and gaps.

Within the current institutional landscape, characterized by increased societal and governmental emphasis on environmental preservation, there is growing interest in the potential of digital transformation (DT) to advance the circular economy (CE). Nonetheless, the empirical substantiation of the connection between DT and CE remains limited. This study seeks to investigate the impact of DT on CE at the organizational level and examine how various institutional factors may shape this relationship within the Chinese context.

To scrutinize this association, we construct a research framework and formulate hypotheses drawing on institutional theory, obtaining panel data from 238 Chinese-listed high-tech manufacturing firms from 2006 to 2019. A regression analysis approach is adopted for the sample data.

Our regression analysis reveals a positive influence of DT on CE performance at the organizational level. Furthermore, our findings suggest that the strength of this relationship is bolstered in the presence of heightened regional institutional development and industry competition. Notably, we find no discernible effect of a firm’s political connections on the DT–CE performance nexus.

This study furnishes empirical evidence on the relationship between DT and CE performance. By elucidating the determinants of this relationship within the distinct context of Chinese institutions, our research offers theoretical and practical insights, thus laying the groundwork for subsequent investigations into this burgeoning area of inquiry.

Diesel engine can produce power more efficiently with lower exhaust emissions when operated at optimum input parameter settings. To achieve this goal, the purpose of this paper is to optimize the input parameters of diesel engine which will lead to optimum performance and exhaust emissions.

To achieve the goal of improving diesel engine performance and exhaust emissions, four input parameters were considered in the study. Five different levels of each input parameter were taken. Four response variables under no load, half load and full load conditions were recorded. Experiments were performed in random manner according to selected Taguchi L25 orthogonal array. The data were analyzed using grey relational analysis coupled with principal component analysis. Analysis of S/N ratio was performed to obtain the optimum combination of input parameters. The grey relational grade at optimum setting of the input parameters was obtained by regression analysis.

Results of the current research work give the optimum input parameter settings for no load, half load and full load conditions of diesel engine. Engine produces power more efficiently with low exhaust emissions when operated at these optimum settings.

In view of the compliance to the stringent air pollution norms of the nations and fast depleting fossil fuels, it is of the utmost importance to design and operate the engine in the optimum range of its input parameters so that it produces more power with low exhaust emissions. This paper aims at optimizing input parameters of diesel engine to improve performance and exhaust emissions. Results of the study presented in this paper are significantly useful for diesel engine-related researchers and professionals.

From the literature review, it appears that only few researchers have conducted studies pertaining to the optimization of the input parameters of diesel engine to improve performance or exhaust emissions. Although few studies related to the optimization of compression ratio, fuel injection timing, fuel injection pressure and air pressure have been reported, no work related to optimization of temperature and pressure of turbocharged air has been reported. Therefore, the main focus of the current research work is on optimizing the charge air temperature and pressure with respect to performance and exhaust emissions.

The purpose of this paper is to attain higher effectiveness with an introduction of Joule–Thomson effect on a three-fluid heat exchanger with two communications. It also gives a range of parameter values that have to be maintained for achieving effectiveness above 0.85. Attaining effectiveness above 0.85 is very important for the heat exchanger to perform the liquefaction of hot fluid.

The analysis is conducted using Galerkin’s method, a finite element approach.

This investigation determines crucial values for the cryogenic heat exchanger to achieve effectiveness above 0.85. The important findings are as follows: effectiveness above 0.85 is attained if the heat exchanger size is within the range of 8–10; ratio of heat flow resistance between intermediate and hot stream to heat flow resistance between cold and hot stream should be maintained between 1 and 10; the intermediate fluid temperature should be maintained between 0 and 0.2; the ratio of thermal capacity of the hot fluid relative to a cold fluid should be maintained between 1.25 and 1.42; and the ratio of thermal capacity of the hot fluid relative to an intermediate fluid should be maintained between 2 and 2.5.

The investigation has presented a finding for improving the effectiveness of the cryogenic heat exchanger. Higher the Joule–Thomson pressure drop effect, more is the drop in temperature of the fluid resulting in additional cooling or lowering of the fluid temperature. The practical implementation is also explained, i.e. to achieve practically the Joule–Thomson pressure drop in a cryogenic heat exchanger.

To the best of the authors’ knowledge, no investigations were carried out previously on Joule–Thomson investigation on a three-fluid heat exchanger with two communications, for different values of Joule–Thomson pressure drop.