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Article
Publication date: 4 January 2021

Huichao Wang, Qin Lian, Dichen Li, Chenghong Li, Tingze Zhao and Jin Liang

Reconstructing multi-layer tissue structure using cell printing to repairing complex tissue defect is a challenging task, especially using in situ bioprinting. This study aims to…

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Abstract

Purpose

Reconstructing multi-layer tissue structure using cell printing to repairing complex tissue defect is a challenging task, especially using in situ bioprinting. This study aims to propose a method of in situ bioprinting multi-tissue layering and path planning for complex skin and soft tissue defects.

Design/methodology/approach

The scanned three-dimensional (3D) point cloud of the skin and soft tissue defect is taken as the input data, the depth value of the defect is then calculated using a two-step grid division method, and the tissue layer is judged according to the depth value. Then, the surface layering and path planning in the normal direction are performed for different tissue layers to achieve precise tissue layering filling of complex skin soft tissue defects.

Findings

The two-step grid method can accurately calculate the depth of skin and soft tissue defects and judge the tissue layer accordingly. In the in situ bioprinting experiment of the defect model, the defect can be completely closed. The defect can be reconstructed in situ, and the reconstructed structure is basically the same as the original skin tissue structure, proving the feasibility of the proposed method.

Originality/value

This study proposes an in situ bioprinting multi-tissue layering and path planning method for complex skin and soft tissue defects, which can directly convert the scanned 3D point cloud into a multi-tissue in situ bioprinting path. The printed result has a similar structure to that of the original skin tissue, which can make cells or growth factors act on the corresponding tissue layer targets.

Details

Rapid Prototyping Journal, vol. 27 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 20 December 2023

İdris Tuğrul Gülenç, Mingwen Bai, Ria L. Mitchell, Iain Todd and Beverley J. Inkson

Current methods for the preparation of composite powder feedstock for selective laser melting (SLM) rely on costly nanoparticles or yield inconsistent powder morphology. This study

Abstract

Purpose

Current methods for the preparation of composite powder feedstock for selective laser melting (SLM) rely on costly nanoparticles or yield inconsistent powder morphology. This study aims to develop a cost-effective Ti6Al4V-carbon feedstock, which preserves the parent Ti6Al4V particle’s flowability, and produces in situ TiC-reinforced Ti6Al4V composites with superior traits.

Design/methodology/approach

Ti6Al4V particles were directly mixed with graphite flakes in a planetary ball mill. This composite powder feedstock was used to manufacture in situ TiC-Ti6Al4V composites using various energy densities. Relative porosity, microstructure and hardness of the composites were evaluated for different SLM processing parameters.

Findings

Homogeneously carbon-coated Ti6Al4V particles were produced by direct mixing. After SLM processing, in situ grown 100–500 nm size TiC nanoparticles were distributed within the α-martensite Ti6Al4V matrix. The formation of TiC particles refines the Ti6Al4V β grain size. Relative density varied between 96.4% and 99.5% depending on the processing parameters. Hatch distance, exposure time and point distance were all effective on relative porosity change, whereas only exposure time and point distance were effective on hardness change.

Originality/value

This work introduces a novel, cost-effective powder feedstock preparation method for SLM manufacture of Ti6Al4V-TiC composites. The in situ SLM composites achieved in this study have high relative density values, well-dispersed TiC nanoparticles and increased hardness. In addition, the feedstock preparation method can be readily adapted for various matrix and reinforcement materials in future studies.

Details

Rapid Prototyping Journal, vol. 30 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 7 January 2019

Qin Lian, Xiao Li, Dichen Li, Heng Gu, Weiguo Bian and Xiaoning He

Path planning is an important part of three-dimensional (3D) printing data processing technology. This study aims to propose a new path planning method based on a discontinuous…

Abstract

Purpose

Path planning is an important part of three-dimensional (3D) printing data processing technology. This study aims to propose a new path planning method based on a discontinuous grid partition algorithm of point cloud for in situ printing.

Design/methodology/approach

Three types of parameters (i.e. structural, process and path interruption parameters) were designed to establish the algorithm model with the path error and the computation amount as the dependent variables. The path error (i.e. boundary error and internal error) was further studied and the influence of each parameter on the path point density was analyzed quantitatively. The feasibility of this method was verified by skin in situ printing experiments.

Findings

Path point density was positively correlated with Grid_size and negatively related to other parameters. Point_space, Sparsity and Line_space had greater influence on path point density than Indentation and Grid_size. In skin in situ printing experiment, two layers of orthogonal printing path were generated, and the material was printed accurately in the defect, which proved the feasibility of this method.

Originality/value

This study proposed a new path planning method that converted 3D point cloud data to a printing path directly, providing a new path planning solution for in situ printing. The discontinuous grid partition algorithm achieved controllability of the path planning accuracy and computation amount that could be applied to different processes.

Details

Rapid Prototyping Journal, vol. 25 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 2 March 2020

Hanna Vuojärvi and Saana Korva

This study aims to discover how leadership emerges in a hospital’s trauma team in a simulated trauma care situation. Instead of investigating leadership from a leader-centric…

Abstract

Purpose

This study aims to discover how leadership emerges in a hospital’s trauma team in a simulated trauma care situation. Instead of investigating leadership from a leader-centric perspective, or using a metrics-based approach to reach generalizable results, the study aims to draw from post-heroic theories by applying leadership-as-practice and sociomaterial perspectives that emphasize the cultural-historical context and emergent nature of leadership.

Design/methodology/approach

The study was conducted in a Finnish central hospital through ethnographic observations of 14 in situ trauma simulation trainings over a period of 13 months. The data consist of vignettes developed and written from field notes. The analysis was informed by the cultural-historical activity theory.

Findings

Leadership in a trauma team during an in situ simulation training emerges from a complex system of agencies taking place simultaneously. Contextual elements contributed to the goal. Clarity of roles and task division, strong execution of leadership at critical points, active communication and maintenance of disciplined communication helped to overcome difficulties. The team developed coordination of the process in conjunction with the care.

Originality/value

The study considers trauma leadership to be a practical phenomenon emerging from the trauma team’s sociomaterial context. The results can be used to develop non-technical skills training within the field of simulation-based medical training.

Details

Leadership in Health Services, vol. 33 no. 2
Type: Research Article
ISSN: 1751-1879

Keywords

Article
Publication date: 10 February 2022

Pengxiong Zhao, Wei Wu, Zeyu Ma and Yong Dan

This paper aims to investigate the corrosion evolution process of AZ91 magnesium alloy in 3.5 wt.% NaCl solution under different stresses by using in situ methods, thereby…

Abstract

Purpose

This paper aims to investigate the corrosion evolution process of AZ91 magnesium alloy in 3.5 wt.% NaCl solution under different stresses by using in situ methods, thereby evaluate the influence of stress on the corrosion sensitivity of AZ91 magnesium alloy, and discuss the potential mechanism.

Design/methodology/approach

A four-point bending method was used to apply different loads to the magnesium alloy samples, a charge coupled device camera and electrochemical impedance spectroscopy test being used for in situ study. Scanning electron microscopy and X-ray diffraction (XRD) analysis were performed for corrosion product and morphology characteristics.

Findings

The observation results show that the corrosion of AZ91 magnesium alloy becomes more and more serious with the increase in the stress and generated many corrosion products. Originally, corrosion products prevented alloy matrix from contacting the corrosive medium. However, the increase in the stress facilitated the emergence of the corrosion holes in the corrosion products, which provided the microscopic channels for corrosive solution to attack the Mg alloy matrix, and accelerated the corrosion of the magnesium alloy, resulting in a lot of corrosion pits on the magnesium alloy surface under the corrosion product layer.

Originality/value

The evolution information of corrosion process is crucial to explore the mechanism of corrosion. Currently, most researches about corrosion of magnesium alloy used traditional testing techniques to obtain corrosion information, lacking the direct tracking and monitoring of the corrosion evolution process. Hence, this paper focuses on in situ corrosion study of AZ91 magnesium alloy. The technology with spatial resolution capability observed the changes in magnesium alloy surface at different times in the corrosion process in situ. Meanwhile, the in situ electrochemical technology was used to monitor the changes in micro-electrochemical signals during the corrosion process of magnesium alloy under different stresses.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 28 August 2019

Karen Ramos, Onesimo Cuamea and Jorge Alfonso Galván-León

In Mexico, wine tourism has become a relevant issue in the past 20 years. Research in this region is in a nascent stage and largely focused on the supply side. Nevertheless…

Abstract

Purpose

In Mexico, wine tourism has become a relevant issue in the past 20 years. Research in this region is in a nascent stage and largely focused on the supply side. Nevertheless, consumer behavior research on wine tourists of the region is needed to improve the wine region positioning. Therefore, the purpose of this paper is to find out the predictors for revisit intention (RI) to the Valle de Guadalupe wine route.

Design/methodology/approach

The information was obtained by applying an exit poll survey to a sample of 422 wine tourists at the micro, small and medium wineries in Ensenada, Mexico. The spatial-temporal model was used to predict the wine tourist RI. Three dimensions were used: pre-visit, in situ experience and travel to/from. Multiple linear regressions were carried out to assess the relation between the three dimensions and RI.

Findings

The results obtained show that the pre-visit and in situ dimensions have an effect on RI to the wine route.

Research limitations/implications

The generalization of the results may be limited due to fact that only the repeated visitors of the autumn season are included; therefore, it is not applicable to summer (high season of wine tourism) and first-time visitors.

Practical implications

The results provide implications for the owners of the micro, small and medium wineries seeking to improve the experience and increasing the tourist RI to the wine route.

Originality/value

The theoretical added value of this paper is its contribution to the body of knowledge about the wine tourism spatial-temporal model, evaluating the complete wine tourism experience to predict RI.

Details

International Journal of Wine Business Research, vol. 32 no. 1
Type: Research Article
ISSN: 1751-1062

Keywords

Article
Publication date: 19 September 2016

Georgios Makrygiannakis and Lisa Jack

The purpose of this paper is to suggest a strong structuration-based framework for the study of management accounting change.

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Abstract

Purpose

The purpose of this paper is to suggest a strong structuration-based framework for the study of management accounting change.

Design/methodology/approach

A retrospective field study was designed to investigate the impact of the 2008 financial crisis on budgeting and control practices of Greek hospitality organisations. Conduct analysis addresses agents’ perceptions of the changes upon themselves. Context analysis explores the changing context, and how the agents modified their in-situ control structures accordingly. The framework is demonstrated through one case study.

Findings

The agents in the case, triggered by the crisis, gradually come to criticise the way they practice budgeting. The first response is to practice budgeting more normatively, but later they criticise and modify these norms. As their formal mentalities co-mediated action, variance management became proactive rather than reactive. Variations in the ways agents draw upon structures – unreflectively or critically – and on how they act to reproduce structures – routinely or strategically – characterise change in management accounting practice. Agents’ reasoning and conduct leading to action is local, and these local changes in conduct and context are significant in understanding management accounting change.

Originality/value

This framework for studying management accounting change balances structural conditions of action, with action and interaction. It can be used to study how, why, and by whom institutionalised management accounting practices may change.

Details

Accounting, Auditing & Accountability Journal, vol. 29 no. 7
Type: Research Article
ISSN: 0951-3574

Keywords

Article
Publication date: 1 March 1984

K.M. Verma, S.C. Verma and A.K. Sinha

The paper summarises the merits and limitations of different methods used to determine the rejection criteria of the primary reformer tubes. It compares the microstructures as…

Abstract

The paper summarises the merits and limitations of different methods used to determine the rejection criteria of the primary reformer tubes. It compares the microstructures as obtained on the outer surface of the reformer tubes with that observed in the transverse section in the regions of outer wall, midwall and inner surface. On the basis of these studies coupled with dimensional change measurements, the in situ metallographic technique has been used to monitor the condition of tubes in two reformation units and the tubes had given satisfactory service till the next turnaround as predicted.

Details

Anti-Corrosion Methods and Materials, vol. 31 no. 3
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 13 July 2021

Chen Li, Heng Wen, Kun Chen, Longxiao Zhang, Ting Xie, Yaru Shi and Junlong Zhang

This paper aims to develop a Mini-Tribometer for in-situ observation of subsurface.

Abstract

Purpose

This paper aims to develop a Mini-Tribometer for in-situ observation of subsurface.

Design/methodology/approach

To observe the change of the microstructure during wear in real time, an in-situ observation mini-tribometer was developed according to the requirements of the basic frictional experiments and carried out the verification experiments.

Findings

The subsurface images and the tribological data obtained from the mini-tribometer clearly show that the graphite in the matrix moves to the surface and takes part in lubrication mainly in the form of extrusion and peeling off, and the migration of graphite in the copper-based composite to the frictional interface to act as lubricant and to result in the decrease of the friction coefficient. The experimental results of the developed tribometer are accurate, which can provide important references for further research on the wear mechanism of materials.

Originality/value

The developed in-situ observation mini-tribometer can be used to observe the dynamic wear mechanism of the frictional pairs, which is very important for optimization of material design and tribological performances.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 31 May 2022

Joyce Hei Tong Lau, Huda Khan, Richard Lee, Larry S. Lockshin, Anne Sharp, Jonathan Buckley and Ryan Midgley

Obesity among elderly consumers precipitates undesirable health outcomes. This study aims to investigate the effects of environmental cues on food intake of elderly consumers in

Abstract

Purpose

Obesity among elderly consumers precipitates undesirable health outcomes. This study aims to investigate the effects of environmental cues on food intake of elderly consumers in an aged-care facility.

Design/methodology/approach

A longitudinal study conducted over 17 weeks in situ within an aged-care facility with 31 residents investigated how auditory (soothing music), olfactory (floral-scented candle) and visual (infographic on health benefits of the main meal component) cues influenced food intake quantity during a meal, while accounting for portion size effect (PSE).

Findings

Analysing the cross-sectional results of individual treatments and rounds did not reveal any consistent patterns in the influence of the three environmental cues. Longitudinal analyses, however, showed that the presence of auditory and olfactory cues significantly increased food intake, but the visual cue did not. Moreover, PSE was strong.

Research limitations/implications

Extending research into environmental factors from a commercial to a health-care setting, this study demonstrates how the presence of auditory and olfactory, but not cognitive cues, increased food intake behaviour among elderly consumers. It also shows that a cross-sectional approach to such studies would have yielded inconclusive or even misleading findings. Merely serving more would also lead to higher food intake amount.

Practical implications

Environmental factors should be a part of health-care providers’ arsenal to manage obesity. They are practical and relatively inexpensive to implement across different health-care settings. However, the same environmental factors would have opposite desired-effects with normal or underweight residents, and hence, aged-care facilities need to separate the dining experience (or mealtime) of obese and other residents. Quantity served should also be moderated to discourage overeating.

Originality/value

While studies into managing obesity, particularly among older adults, have mainly focused on techniques such as pharmacotherapy treatments with drugs, dietary management or even lifestyle change, less attention has been given to the influence of environmental cues. This study, executed in situ within an aged-care facility, provided evidence of the importance of considering the impact of environmental factors on food intake to help reduce obesity.

Details

European Journal of Marketing, vol. 56 no. 11
Type: Research Article
ISSN: 0309-0566

Keywords

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