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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…

515

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

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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…

501

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

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Article
Publication date: 12 June 2019

Qin Lian, Linian Zhou, Xiao Li, Wei Mao and Dichen Li

The purpose of this paper is to present a new method for the fabrication of a large-scaled muscle scaffold containing an artificial hollow tube network, which may solve the…

400

Abstract

Purpose

The purpose of this paper is to present a new method for the fabrication of a large-scaled muscle scaffold containing an artificial hollow tube network, which may solve the problems of nutrient supply, oxygen exchange and metabolic waste removal.

Design/methodology/approach

In this paper, a ferric chloride structural strength-enhanced sodium alginate hollow tube was used to build the hollow tube network. Gelatin infill was then added to make a large alginate/gelation gel soft tissue scaffold. A pilot experiment was performed and an osmotic test platform was built to study the perfusion and osmotic ability of the 3D printed hollow tube. The essential fabrication parameters (printing velocity and gap) for building the vascular (i.e., hollow tube) network-contained scaffold were investigated. Moreover, cells in culture were spread within the gelation scaffold, and the circulation characteristics of the hollow tube network were studied.

Findings

The printed large-scaled scaffold that contained a ferric chloride structural strength-enhanced sodium alginate hollow tube had good perfusion ability. The osmotic distance of the hollow tube reached 3.7 mm in 8 h in this experiment.

Research limitations/implications

The osmotic distance was confirmed by perfusing a phenol solution; although it is more reliable to test for cell viability, this will be investigated in our later research.

Practical implications

This research may provide new insights in the area of tissue engineering for large-scaled vascularized scaffold fabrication.

Originality/value

This paper presents a new method for fabricating large-scaled scaffolds, and the perfusion ability and osmotic distance of a ferric chloride structural strength-enhanced sodium alginate hollow tube are shown.

Details

Rapid Prototyping Journal, vol. 26 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 2 January 2018

Qin Lian, Wenquan Sui, Xiangquan Wu, Fei Yang and Shaopeng Yang

This paper aims to develop an additive manufacturing technique for complex zirconia ceramic dental bridges.

1588

Abstract

Purpose

This paper aims to develop an additive manufacturing technique for complex zirconia ceramic dental bridges.

Design/methodology/approach

To carry out this study, a dental bridge model was obtained by three-dimensional reverse engineering, and a light-curable zirconia ceramic suspension was formulated. Zirconia bridges were manufactured by stereolithography and then treated by vacuum freeze drying, vacuum infiltration and sintering. The optimal scanning speed was determined according to the shape precision comparison. Then, characteristics of the sintered ceramic parts were tested as size shrinkage, relative density, surface Vickers hardness, surface roughness and microstructure.

Findings

The method for preparation of light-curable zirconia suspension (40 volume per cent solid loading) with a viscosity value of 127 mPa·s was proposed. The optimal laser scanning speed for zirconia bridge fabrication was 1200 mm/s. A relative density of 98.58 per cent was achieved; the obtained surface Vickers hardness and surface roughness were 1,398 HV and 2.06 µm, respectively.

Originality/value

This paper provides a potential technical method for manufacturing complex zirconia dental bridges and other small complex-shaped ceramic components which are difficult to be made by other manufacturing techniques.

Details

Rapid Prototyping Journal, vol. 24 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 18 October 2018

Xiangquan Wu, Qin Lian, Dichen Li and Zhongmin Jin

This study aims to develop a multi-material stereolithography (MMSL) technique to directly fabricate a biphasic osteochondral scaffold.

739

Abstract

Purpose

This study aims to develop a multi-material stereolithography (MMSL) technique to directly fabricate a biphasic osteochondral scaffold.

Design/methodology/approach

A bespoke prototype MMSL system was developed based on a bottom-up mask projection approach. The system was controlled by a multi-material fabrication algorithm with minimum number of switching cycles during fabrication. A variable-power light source was used to fabricate materials with significantly different curing characteristics. The light-curable poly(ethylene glycol) diacrylate (PEGDA) hydrogel and beta-tricalcium phosphate (β-TCP) ceramic suspension were used for fabricating the biphasic osteochondral scaffold.

Findings

The bonding strength of the multi-material interface is shown to be mainly affected by the type of photopolymer, rather than the switching of the materials in MMSL. Lighting power densities of 2.64 and 14.98 mW/cm2 were used for curing the PEGDA hydrogel and the ß-TCP ceramic suspension, respectively. A biphasic osteochondral scaffold with complex interface was successfully fabricated.

Originality/value

This study proposes a potential technical method (MMSL) for manufacturing a complex biphasic osteochondral scaffold composing a PEGDA hydrogel/ß-TCP ceramic composite in a time-efficient and precise manner. The designed bone-cartilage scaffold interface and the surface of the cartilage scaffold can be precisely manufactured.

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Article
Publication date: 7 October 2014

Maggie M. Wang, Cherrie J.H. Zhu, Connie Zheng and Susan Mayson

The purpose of this paper is to explore suzhi requirements and expectations to double-shouldered academics as middle-level cadres (双肩挑处级干部) in a Chinese higher education institute…

259

Abstract

Purpose

The purpose of this paper is to explore suzhi requirements and expectations to double-shouldered academics as middle-level cadres (双肩挑处级干部) in a Chinese higher education institute (HEI) as an initial step to examine the interplays between suzhi requirement and expectations and organizational operational mechanism in the Chinese context.

Design/methodology/approach

The study adopted an exploratory single-case approach for the study. In this study, 22 participants composed of middle-level cadres, other stakeholders at the university, college/department and business unit levels were interviewed.

Findings

Suzhi requirements for the cadres followed the Communist Party of China’s (CPC) guideline, the required de, neng, qin, ji and lian (德, 能, 勤, 绩, 廉) was abstract and vague. With the parallel systems, the CPC and administrative lines, there were discrepancies between the CPC required suzhi and those expected by the stakeholders. A social phenomenon, “official rank-oriented standard” (ORS, guan ben wei, 官本位), was found significantly intertwining with the self suzhi expectation of the cadres, unveiling a more complex dynamics than most research reported for the Chinese public sector organizations (PSOs).

Researchimplications

With the initial qualitative findings unveiling suzhi as an organizational construct, this study informs future empirical research in the indigenous suzhi phenomenon in organizational setting. The conceptualized results of our study offer new insight for future indigenous Chinese management research in all PSOs including state-owned enterprises (SOEs).

Originality/value

As an initial step, this study endeavored to explore suzhi as an organizational construct in a Chinese HEI. The paper contributes to the literature by unveiling the complexity of PSOs in the interplays of dual management systems and ORS coupled with dual-role suzhi requirements for the cadres.

Details

Journal of Chinese Human Resource Management, vol. 5 no. 2
Type: Research Article
ISSN: 2040-8005

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Article
Publication date: 16 January 2009

Sekou Singare, Qin Lian, Wei Ping Wang, Jue Wang, Yaxiong Liu, Dichen Li and Bingheng Lu

This paper aims to describe computer‐aided design and rapid prototyping (RP) systems for the preoperative planning and fabrication of custom‐made implant.

2283

Abstract

Purpose

This paper aims to describe computer‐aided design and rapid prototyping (RP) systems for the preoperative planning and fabrication of custom‐made implant.

Design/methodology/approach

A patient with mandible defect underwent reconstruction using custom‐made implant. 3D models of the patient's skull are generated based on computed tomography image data. After evaluation of the 3D reconstructed image, it was identified that some bone fragment was moved due to the missing segment. During the implant design process, the correct position of the bone fragment was defined and the geometry of the custom‐made implant was generated based on mirror image technique and is fabricated by a RP machine. Surgical approach such as preoperative planning and simulation of surgical procedures was performed using the fabricated skull models and custom‐made implant.

Findings

Results show that the stereolithography model provided an accurate tool for preoperative, surgical simulation.

Research limitations/implications

The methods described above suffer from the expensive cost of RP technique.

Practical implications

This method allows accurate fabrication of the implant. The advantages of using this technique are that the physical model of the implant is fitted on the skull model so that the surgeon can plan and rehearse the surgery in advance and a less invasive surgical procedure and less time‐consuming reconstructive and an adequate esthetic can result.

Originality/value

The method improves the reconstructive surgery and reduces the risk of a second intervention, and the psychological stress of the patient will be eliminated.

Details

Rapid Prototyping Journal, vol. 15 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 13 January 2012

Weiguo Bian, Dichen Li, Qin Lian, Xiang Li, Weijie Zhang, Kunzheng Wang and Zhongmin Jin

The purpose of this paper is to fabricate and characterize osteochondral beta‐tricalcium phosphate/collagen scaffold with bio‐inspired design by ceramic stereolithography (CSL…

2194

Abstract

Purpose

The purpose of this paper is to fabricate and characterize osteochondral beta‐tricalcium phosphate/collagen scaffold with bio‐inspired design by ceramic stereolithography (CSL) and gel casting.

Design/methodology/approach

Histological analysis was applied to explore the morphological characteristics of the transitional structure between the bone and the cartilage. The acquired data were used to design biomimetic biphasic scaffolds, which include the bone phase, cartilage phase, and their transitional structure. The engineered scaffolds were fabricated from β‐TCP‐collagen by CSL and gel casting. The cartilage phase was added to the ceramic phase by gel‐casting and freeze drying.

Findings

The resulting ceramic scaffolds were composed of a bone phase with the following properties: 700‐900 μm pore size, 200‐500 μm interconnected pores size, 50‐65 percent porosity, fully interconnected, ∼12 Mpa compressive strength. A suitable binding force between cartilage phase and ceramic phase was achieved by physical locking that was created by the biomimetic transitional structure. Cellular evaluation showed satisfactory results.

Research limitations/implications

This study is the first try to apply CSL to fabricate biological implants with β‐TCP and type‐I collagen. There are still some defects in the composition of the slurry and the fabrication process.

Practical implications

This strategy of osteochondral scaffold fabrication can be implemented to construct an osteochondral complex that is similar to native tissue.

Originality/value

The CSL technique is highly accurate, as well as biologically secure, when fabricating ceramic tissue engineering scaffolds and may be a promising method to construct hard tissue with delicate structures. The present strategy enhances the versatility of scaffold fabrication by RP.

Details

Rapid Prototyping Journal, vol. 18 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 5 June 2017

Xue Shouqing and Xue Zhaomin

This paper aims to improve the anti-corrosion of oil transportation pipelines.

137

Abstract

Purpose

This paper aims to improve the anti-corrosion of oil transportation pipelines.

Design/methodology/approach

The authors provide a simple, efficient and inexpensive one-pot method for the novel thiadiazole derivatives synthesized using 2-substituted [1, 3, 4] thiadiazole, P2O5 and chloroacetic acid as materials by using XH-200A computer microwave solid-liquid phase synthesizer. The results showed that microwave heating can finish the reaction sufficiently in 20 min, and the optimal addition reaction conditions were n([1, 3, 4] thiadiazole):n(chloroacetic acid):P2O5 = 1:1.2:1.3. Under such conditions, the yield of the title products was 54 per cent.

Findings

The structure of the title compounds were all confirmed by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy. Water-based inhibitors corrosion behaviors on the stainless steel (SS) surface in 1 mol/L HCl solution at room temperature were also studied by weight loss methods and polarization curves. The results of the curves showed that an appropriate amount of 2a (40 ppm) can improve the anti-corrosion efficiency, whereas an excessive amount of 2a (e.g. 50 ppm) may not significantly increase the anti-corrosion efficiency.

Originality/value

In view of continuation of our studies, this paper presents microwave-assisted one-pot synthesis of 2-substitued [1, 3, 4] thiadiazole derivatives, and its anti-corrosion performance was tested by weight loss methods and polarization curves.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 11 April 2023

Xuhong Xu, Tiancheng Hu, Rui Guo, Shang Chen and Lutao Ning

This paper proposes a framework for director evaluation in the context of Chinese state-owned enterprises (SOEs), taking into account the influences of traditional and modern…

140

Abstract

Purpose

This paper proposes a framework for director evaluation in the context of Chinese state-owned enterprises (SOEs), taking into account the influences of traditional and modern Chinese ideologies.

Design/methodology/approach

Following the Delphi method, a series of semi-structured interviews were conducted with Chinese SOE directors.

Findings

The framework used has been validated by examining seven dimensions of virtue and four dimensions of competence functions in Chinese SOEs. Effective and representative characteristics of each dimension are identified through interviews.

Originality/value

First, through this research, indicators of virtue have been materialized and those of competence have been specified in a broader range. Second, this research provides advice for training of candidate directors whose experience were in private firms before they step in as SOE directors.

Details

International Journal of Emerging Markets, vol. 20 no. 1
Type: Research Article
ISSN: 1746-8809

Keywords

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