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The purpose of this paper is to present investigations on the significant influence of the tube material and fin density on fluid elastic instability and vortex shedding in a parallel triangular finned tube array subjected to water cross flow.

The experiment was conducted on finned tube arrays with a fin height of 6 mm and fin density of 3 fins per inch (fpi) and 9 fpi. A dedicated setup has been developed to examine fluid elastic instability and vortex shedding. Nine parallel triangular tube arrays with a pitch to tube diameter ratio of 1.78 were considered. The plain tube arrays, coarse finned tube arrays and fine finned tube arrays each of steel, copper and aluminium materials were tested. Plain tube arrays were tested to compare the results of the finned tube arrays having an effective tube diameter same as that of the plain tube.

A significant effect of fin density and tube material with a variable mass damping parameter was observed on the instability threshold. In the parallel triangular finned tube array subjected to water cross flow, a delay in the instability threshold was observed with an increase in fin density. For steel and aluminium tube arrays, the natural frequency is 9.77 Hz and 10.38 Hz, which is close to each other, whereas natural frequency of the copper tubes is 7.40 Hz. The Connors’ stability constant K for steel and aluminium tube arrays is 4.78 and 4.87, respectively, whereas it is 5.76 for copper tube arrays, which increases considerably compared to aluminum and steel tube arrays. The existence of vortex shedding is confirmed by comparing experimental results with Owen’s hypothesis and the Strouhal number and Reynolds number relationship.

This paper’s results contribute to understand the effect of tube materials and fin density on fluid elastic instability threshold of finned tube arrays subjected to water cross flow.

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

Research in the business-to-business (B2B) and user entrepreneurship literature agrees that “user-driven” perspectives allow entrepreneurs to develop innovative products superior to conventional products. Other researchers argue that such “user-driven” products have limited success and limited impact in certain markets (e.g. niche and industrial markets). This study aims to understand the extent to which user input or co-creation becomes critical in determining product performance.

The key informant approach is used for data collection. Data were collected using a survey instrument via an online panel. Existing scales are used to measure all the focal constructs. Partial least square-based structural equation modeling was used to check for the psychometric properties of the scales and test the hypotheses.

The results indicate that user entrepreneurship is significantly related to firm collaboration efforts and customer collaboration efforts in the B2B market. Both firm collaboration efforts and customer collaboration efforts are significantly related to product performance and mediate the relationship between user entrepreneurship and product performance. Also, findings show that there is an “n” relationship between firm collaboration efforts and product performance.

This study supports the concerns raised by researchers about the dark side of value co-creation and highlights that value co-creation can impede product performance when user entrepreneurs lay too much emphasis on the collaboration processes.

This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health care. The purpose of this paper is to summarize the current state of the field, identify challenges and limitations and discuss future prospects for the development of saliva-based electrochemical sensors.

The paper reviews relevant literature and research articles to examine the latest developments in electrochemical sensing technologies for saliva analysis. It explores the use of various electrode materials, including carbon nanomaterial, metal nanoparticles and conducting polymers, as well as the integration of microfluidics, lab-on-a-chip (LOC) devices and wearable/implantable technologies. The design and fabrication methodologies used in these sensors are discussed, along with sample preparation techniques and biorecognition elements for enhancing sensor performance.

Electrochemical sensors for salivary analyte detection have demonstrated excellent potential for noninvasive, rapid and cost-effective diagnostics. Recent advancements have resulted in improved sensor selectivity, stability, sensitivity and compatibility with complex saliva samples. Integration with microfluidics and LOC technologies has shown promise in enhancing sensor efficiency and accuracy. In addition, wearable and implantable sensors enable continuous, real-time monitoring of salivary analytes, opening new avenues for personalized health care and disease management.

This review presents an up-to-date overview of electrochemical sensors for analyte detection in saliva, offering insights into their design, fabrication and performance. It highlights the originality and value of integrating electrochemical sensing with microfluidics, wearable/implantable technologies and point-of-care testing platforms. The review also identifies challenges and limitations, such as interference from other saliva components and the need for improved stability and reproducibility. Future prospects include the development of novel microfluidic devices, advanced materials and user-friendly diagnostic devices to unlock the full potential of saliva-based electrochemical sensing in clinical practice.

The main purpose of the study was to synthesise the role of COVID-19 social media messages and indigenous religious beliefs on public health promotion initiatives among rural consumers in Zimbabwe.

A qualitative approach was adopted. Population consisting of 15 interviews and six focus groups was purposively sampled from Manicaland, Mashonaland Central and Masvingo provinces in Zimbabwe. A thematic approach was used to present and analyse the data.

Rural consumers believed WhatsApp messages posted by people whom they know or influential personnel like health workers. Credibility of WhatsApp messages was enhanced through its ability to send videos and audios. Teachings and indoctrination by indigenous churches and misinformation were found to be an impediment in believing COVID-19 WhatsApp messages and vaccination by rural consumers. Faith healers in indigenous churches used various practices and artefacts like holy water, stone pebbles, clay pots, flags and wooden rods to pray and treat patients suffering from COVID-19 and other ailments.

Social media messages, religious teachings and indoctrination may be a hindrance to rural consumers in adopting government public health promotion initiatives; hence, public health professionals need prior emic understanding and co-option of local leadership in vaccination campaigns.

This study outstretches the theoretical landscape in consumer behaviour and also practical contribution to health practitioners and marketers on breaking indigenous religious barriers and social media misconceptions on vaccination uptake through promotional strategies earmarked for rural consumers.

Service–sales ambidexterity (SSA) offers sales managers crucial information about dealing with customer service failures through an effective management control system. This study aims to scrutinize the relationships among SSA, salesforce control system, salesperson’s role stressors and service recovery performance (SRP) in the business-to-business (B2B) context.

An analysis is conducted based on survey data collected from 586 B2B sales employees participating in an extensive survey. Structural equation modeling is used to analyze the proposed hypotheses.

Empirical findings suggest that behavior-based control harms SSA. On the other hand, outcome-based control has a positive impact on SSA. The research outcomes further disclose that SSA positively impacts salesperson role conflict and emotional fatigue, whereas emotional fatigue negatively impacts SRP. Salesperson resilience notably moderates the association between SSA and emotional fatigue.

The study addresses there is a dearth of research on SSA applying the sales management control system. When studying about ambidexterity in sales context, many supervisory styles have been explored; however, to the best of the authors’ knowledge, this is the first systematic attempt to understand how sales management control systems play a role in SSA.

This paper studies the impact of different chief executive officer (CEO) succession strategies on consumer evaluation of family firms. CEO succession is critical for family firms as improper succession planning has been shown to be the primary reason for high mortality rates of such firms. Furthermore, the choice of CEO (internal vs external) by family firms can send different signals to stakeholders and thereby impact their appraisal of such firms.

In this paper, the authors use an experiment-based approach to test how the type of CEO succession (internal vs external) influences the consumer's evaluation of family firms.

The authors find that appointing an internal CEO leads to higher perception of firm capability, trust towards the firm and more favorable consumer attitudes. All these factors, in turn, lead to higher purchase intentions. External CEOs in family firms do not seem to have any de facto advantage regarding perceptions of higher capability.

Thus, the authors contribute to the literature of family firms by showing how family firm's strategic decisions during succession can affect consumer behavior.

This study was design to investigate of P. aeruginosa, an example of Gram-negative bacteria, in seven primary and secondary schools of Baghdad city, and the effects of Ethanol and Dettol of P. aeruginosa biofilm.

Seventy swabs were collected from seven primary and secondary schools of Baghdad city, Iraq, during November -December 2022. Swabs were collected from classes desk, doors handles, students hands and water taps. Standard microbiological testing methods were used on the samples for isolation and identification. The ability of bacteria to form biofilm and the effects of Ethanol and Dettol on"preformed” biofilms was examined by microtiter plate with the use of an ELISA reader.

In 70 swabs from seven primary and secondary schools, growth was observed in 33 swabs as P. aeruginosa. Primary schools were higher contaminated than secondary and water taps and door handles represented the main source of this contamination. The ability of bacteria to produce biofilm was observed in 19 (57.6%) isolates and 14 (42.4%) nonbiofilm producers. As well as, Ethanol (70%) treatment of preformed biofilms led to enhance biofilm formation and revealed significantly greater staining after 4 and 24h than Dettol (3%) compared to an untreated control (tryptic soy broth (TSB) incubation).

Studies on P. aeruginosa in Iraqi schools are quite rare. This work is considered distinctive because it drew attention to the presence of pathogenic bacteria within primary and secondary schools, which are not considered their natural environment.

Cold-formed steel has been used extensively as secondary elements such as purlins and girts in building frames. Purlin is critical to the structure of the roof because it supports the weight of the roof deck and aids to make the entire roof structure more rigid. Furthermore, cold-formed steel purlin is a replacement for wood purlin because steel purlins are light weight and more economical. Hence, the purpose of this study to investigate the effect of opening due to torsion behaviour.

This analysis used cold-formed steel hat purlin with and without openings (WOs) under different opening shape, location and spacing by using finite element LUSAS software.

The finite element results showed that purlin with openings had higher angle of rotation than section WO, with a percentage difference of not more than 6%. When the opening was located at mid-span, the angle of rotation reduced. Angle of rotation increased when the opening spacing increased. Number of openings also affected the torsional behaviour of the purlin. Five opening shapes, which were circle, diamond, C-hexagon, square and elongated circle, were studied. Among all the shapes, purlin with diamond opening was more resistance to torsion.

The use of cold-formed steel section with web openings (rectangular or circular) is a practical solution when it is required to pass service ducts through the structural member. However, the presence of opening gives minor effect on the structural behaviour of cold-formed steel hat purlin.

This study aims to examine the constructs of job satisfaction and organizational commitment (OC) as the determinants of customer-perceived service quality in higher education context. It also explores the role of OC in mediating the dynamics of the relationship.

It applied the cross-sectional, ex post facto survey method to acquire data from 1,776 respondents at Aden University. Two sets of questionnaires on job satisfaction, OC and perceived service quality were filled out by 296 academic staff and 1,480 students. Data were analyzed using structural equation modeling.

The results showed that job satisfaction exercised a significant positive effect on OC and students’ perception of service quality (i.e. the quality of lectures delivered in class that shaped their learning experiences). OC also significantly affected students’ perception of service quality and partially mediated the effect of job satisfaction on perceived service quality.

The current research only investigated the outcomes of job satisfaction and did not cover critical antecedents of job satisfaction, such as employee training and development, rewards and benefits and the like. Its outcomes have important implications for managing the link between organizational practices and customers perception of service quality in higher education context.

The results have accentuated the importance of universities’ ensuring and increasing faculty’s job satisfaction and commitment if they seek to enhance students’ perception of service quality. Universities can do so by improving their organizational practices, which are expected to result in faculty well-being and improved working conditions.

The results have contributed new insights into the current understanding of the dynamics between and among job satisfaction, OC and customers’ perceptions of service quality. It has demonstrated how OC is shaped by job satisfaction and can influence the quality of services rendered by employees if they are happy and satisfied with the organization.