bluuebunny/crossref_metadata_2025 huggingface dataset:
How to visualize performance measures in a manufacturing SME
Authors: Larsson Carina , Syberfeldt Anna , Säfsten Kristina
Published: October 2017

Purpose

The purpose of this paper is to identify strengths and weaknesses in the communication of performance measures and propose guidelines for the visualization of performance measures supporting continuous improvement (CI) in manufacturing small and medium-sized enterprises (SMEs). The goal is to help manufacturing SMEs improve their communication of performance measures, thereby improving performance, and strengthening the company.

Design/methodology/approach

This paper draws on both theoretical and empirical research. It begins with a literature review of theoretical guidelines for the visualization of performance measures. This theoretical information is then supplemented with a case study and a survey, both carried out at the Vara plant, a manufacturing SME with well-developed communication of performance measures. The case study involved all organizational levels in the company and focused on identifying strengths and weaknesses in visual communication of performance measures supporting CI. The information acquired from the literature survey and the case study was then used as the basis for a survey of the employees in one department as regards their perception, understanding and opinion of visual communication of performance measures. The analysis of the results led to the development of guidelines and a substantive proposal improving visualization of performance measures in this specific company, and in manufacturing SMEs in general.

Findings

A model for the visualization of performance measures supporting CI in the company was carried out. The guidelines proposed for all such visualizations are as follows: keep the visualization as simple as possible without compromising understanding, use symbols and colors consistently, use simple words and do not include too much information in the visualization. The study also shows that it is important to support a written visualization with an oral presentation to explain the results.

Originality/value

The originality of this paper lies in its focus on the visualization of performance measures in manufacturing SMEs and the guidelines and proposals developed.
How CEO underpayment influences strategic change: the equity perspective
Authors: Wang Linlin , Jiang Wan
Published: October 2017

Purpose

The purpose of this paper is to examine how the magnitude of strategic change may be influenced by Chief executive officer (CEO) underpayment relative to comparison CEOs. Based on equity theory, the authors propose that compensation inequity motivates underpaid CEOs to restore equity, which can take the form of making a greater magnitude of strategic change. In addition, this study proposes three important moderators of the relationship between CEO underpayment and strategic change.

Design/methodology/approach

Results from a sample covered in the Standard & Poor’s (S&P) ExecuComp database for the years 1996-2014 provide support for these theoretical predictions.

Findings

CEO underpayment has a positive effect on the magnitude of strategic change. Top management team compensation gap and firm slack are proposed to weaken the impact of CEO underpayment on strategic change, while environmental complexity is predicted to strengthen the relationship between CEO underpayment and strategic change.

Originality/value

This study contributes to strategic change literature by linking research on CEO relative compensation to strategic change studies. This study contributes to equity theory and CEO relative compensation literature by extending its implications to firms’ decisions on strategic change. Moreover, it also contributes to equity theory by revealing the boundary conditions that mitigate or aggravate the impacts of CEO underpayment on firms’ strategic decisions.
Got a plan in the pipeline? Nominating committee’s information processing in executive successions
Authors: Walther Axel , Calabrò Andrea , Morner Michèle
Published: October 2017

Purpose

The purpose of this paper is to examine how information-processing mechanisms between nominating committees (NCs), incumbent executives, board chairs, and shareholders affect the comprehensiveness of executive succession processes.

Design/methodology/approach

The authors employ an explanatory multiple-case study that comprises eight CEO and CFO succession cases in large German publicly traded firms.

Findings

The findings reveal that comprehensiveness is determined by four key information-processing mechanisms: the effectiveness of NC’s information sharing, absorbing disagreement, and integrating heterogeneous opinions; board chair leadership (i.e. an apprentice board leadership structure in association with the board chair’s openness to ideas); the breadth and depth of information sharing between executives and NCs; and the extent and timing to which major shareholders influence succession processes.

Research limitations/implications

The authors summarize the findings in a conceptual framework and develop a set of propositions to guide future research on the topic. Such studies may want to test the suggestions in a quantitative way, preferably in a multinational context.

Originality/value

The authors’ emerging conceptual framework contributes a set of information-processing variables by which NCs engage in comprehensive executive successions with incumbent executives, board chairs, and major shareholders and offers a multiechelon approach to study executive successions.
Creating value through the balanced scorecard: how does it work?
Authors: Llach Josep , Bagur Llorenç , Perramon Jordi , Marimon Frederic
Published: October 2017

Purpose

The purpose of this paper is to further research on the Kaplan and Norton (1996) balanced scorecard (BSC) model after having discerned that previous work has so far neglected to explore the interrelationships between the model’s dimensions and the influence contextual factors may have.

Design/methodology/approach

The data set used to meet this paper’s main objectives was collected using a structured online survey sent to the member companies of the Catalan Association of Accounting and Management (ACCID). Specifically, the surveys were directed to the heads of the finance departments. From the 3,500 mails sent, 336 companies decided to participate in the study. These figures represent an acceptable response rate of 9.6 per cent. As 83 of the companies declared that they would only use financial indicators, the final study sample totalled 253 firms.

Findings

The results demonstrate the mediating effects intermediate constructs have, and highlight how important leadership is in achieving success or high performance. These results follow on from previous empirical literature that analysed other management systems such as the Baldrige, the EFQM or the Deming models. In addition, some differences in the relationships as per the contextual factors studied have been detected. Therefore, the conclusions reached in this paper will be of interest to both academics and professionals in perceiving and understanding the logical flow of consequences any decision taken will produce.

Originality/value

The authors’ main contributions are: to have strictly followed the theoretical BSC model by combining both formative and reflective dimensions using the emerging partial least squares methodology; to have based the study on 253 firms and to have used 37 category indicators which, to our knowledge, are more than any other previous work; to have developed a mediation model designed to appreciate the interrelationships the dimensions in the BSC model have; to have analysed the possible differences there are in the interrelationships between the dimensions using two widely accepted influencing contextual factors in current literature, namely a firm’s size and its typology.
Are environmental strategies profitable for companies? The key role of natural competences from a resource-based view
Authors: Brulhart Franck , Gherra Sandrine , Marais Magalie
Published: October 2017

Purpose

The purpose of this paper is to investigate the relationship between proactive environmental strategies (PES) and economic performance from a resource-based view. The authors determine the nature of this relationship and the processes and conditions that are involved. The mediating role of natural competences is a major focus, particularly the effect of their simultaneous development on economic performance.

Design/methodology/approach

The authors use structural equation modeling on a sample of 188 companies from the food-processing and household products industries in France.

Findings

The results confirm the positive impact of PES on economic performance. Unlike the natural competences individually, the simultaneous development of these competences mediates the relationship. The results also highlight the influence of conventional competences on economic performance and the impact of organizational and procedural competences on the level of simultaneously developed competences.

Practical implications

The study demonstrates the economic benefits of PES to practitioners. Moreover, it provides them the information on the key role of natural competences and how they can be developed to make PES profitable.

Originality/value

The findings support a “win-win” view of the PES-economic performance relationship, whereas prior studies showed contrasting evidence. The main contribution lies in the consideration of natural competences in this relationship and in their operationalization.
The antecedents and impact of industry consultants on the future performance of new banks
Authors: DeVaughn Michael L. , Leary Myleen
Published: October 2017

Purpose

The purpose of this paper is to examine the antecedents and performance outcomes when startup firms in the US banking industry hire industry consultants.

Design/methodology/approach

This study uses a sample of prospective startup banks that applied for a new bank charter application in Florida between 1996 and 2005. Logistic regression, ordinary least squares or ordered logistic regression models were used to test hypotheses.

Findings

Analysis suggests complexity and regulatory change are factors in a founder’s decision to hire a consultant. Consultants have a positive impact on firm financial performance but not on a composite multifactor measure of performance. Additional analyses suggest the effectiveness of consulting assistance hinges on specific attributes of the consulting firm, but cumulative consulting experience is not one of these attributes.

Research limitations/implications

This study focuses on the impact of consultants on new venture performance in a single industry using archival data. Additional research is likely needed to test the generalizability of the findings in other research contexts and examine motives beyond the financial ones investigated in this study.

Practical implications

Results suggest that hiring a consultant at startup can satisfy financial stakeholders, but, in a regulated industry, hiring a consultant at startup does not improve a composite, multifactor measure of performance that is important to industry regulators. When deciding whether to commit scarce resources to hiring consultants, founding teams should be clear which external stakeholder and which measure of performance they are seeking to improve.

Originality/value

While the business advisory role of informal players such as family and friends and more formal players such as board members and federal, state or local governments have been well documented, little attention has been paid to the contributions of industry consultants in startup firms. These overlooked intermediaries play an important role in the successful launch of a new firm. This study examines when and why such advisors might create value for new firms.
On strategic trade-offs: does the principle of energy conservation explain the trade-offs law?
Authors: Thürer Matthias , Stevenson Mark , Sarmiento Roberto , Gianiodis Peter
Published: October 2017

Purpose

The purpose of this paper is to reaffirm the suggestion that there are at least two distinct types of laws of trade-off that affect all firms and, in doing so, to contribute toward resolving the persistent trade-off debate in the literature.

Design/methodology/approach

Conceptual study using implicit deductive reasoning.

Findings

Two types of trade-offs are identified: “internal” can be understood following the dictates of the law of diminishing returns, while “external” can be modeled using the principle of energy conservation.

Research limitations/implications

New insights are provided by discussing the impact of both laws of trade-off on the resource-based view of the firm, on new capabilities such as sustainability and innovativeness and on key strategic choices.

Practical implications

The study explains why trade-offs occur and outlines contextual factors that determine the “strength” of the trade-offs.

Originality/value

To the best of the authors’ knowledge, no previous study has attempted to investigate the topic of strategic trade-offs on the basis of the principle of energy conservation.
An agency perspective on the board of directors and corporate entrepreneurship
Authors: Tribbitt Mark A. , Yang Yi
Published: October 2017

Purpose

The purpose of this study is to examine the relationship between board dependence, antitakeover provisions and their influence on corporate entrepreneurship (CE).

Design/methodology/approach

The study uses agency theory as a framework to expand on the board dependence–CE relationship by injecting the moderating role of antitakeover provisions to the model. Using data collected from 350 publicly traded firms, a panel regression analyses was conducted on both innovation and venturing components of CE.

Findings

The findings of this study show a negative relationship between board dependence and CE. Further this study shows that such a negative relationship becomes weaker when higher levels of antitakeover provisions are injected into the model.

Research limitations/implications

This study was conducted using a sample of large publicly traded firms within the information and manufacturing sectors, and so our findings may not be generalizable to firms in other contexts. Further, other variables representing CE (e.g. new product introductions) may add to this line of research in the future.

Practical implications

Understanding the role of board of directors within a firm may help foster CE throughout the organization.

Originality/value

This study expands on existing research by incorporating the influence of environmental factors (e.g. antitakeover provisions) and examining the relationship between corporate governance and CE using both measures of innovation and venturing.
Evaluation of efficiency and mechanical properties of Inconel 718 components built by wire and powder laser material deposition
Authors: Arrizubieta Jon Iñaki , Klocke Fritz , Klingbeil Nils , Arntz Kristian , Lamikiz Aitzol , Martinez Silvia
Published: October 2017

Purpose

The purpose of this paper is to evaluate and compare powder and wire laser material deposition (LMD) processes.

Design/methodology/approach

In the present paper, Inconel 718 tensile test probes were built layer by layer using a longitudinal strategy, and the quality of the deposited material was characterized for both wire and powder LMD processes. The measured data during the deposition tests have been used for comparing the efficiency of both powder and wire LMD processes. Afterwards, to evaluate the mechanical properties of the parts generated by means of both processes, standard tensile tests were carried out. Furthermore, other factors have been evaluated, such as process reliability or presence of residual material, after the deposition process.

Findings

Results show a higher efficiency of the wire LMD process, and even similar ultimate tensile stress values were reached for both processes; powder LMD parts resulted in a more brittle nature.

Originality/value

In the present paper, a thorough analysis that compared both processes has been carried out. The results obtained will help in the future when choosing between wire and powder LMD. The main points of the wealth of knowledge generated with these research efforts are highlighted herein.
Edge quality in fused deposition modeling: I. Definition and analysis
Authors: Armillotta Antonio , Cavallaro Marco
Published: October 2017

Purpose

The purpose of this paper is to discuss the problem of the geometric accuracy of edges in parts manufactured by the Fused Deposition Modeling process, as a preliminary step for an experimental investigation.

Methodology/approach

Three geometric variables (inclination, included and incidence angles) were defined for an edge. The influence of each variable on the geometric errors was explained with reference to specific causes related to physical phenomena and process constraints.

Findings

Occurrence conditions for all causes were determined and visualized in a process map, which was also developed into a software procedure for the diagnosis of quality issues on digital models of the parts.

Research limitations/implications

The process map was developed by only empirical considerations and does not allow to predict the amount of geometric errors. In the second part of the paper, experimental tests will help to extend and validate the prediction criteria.

Practical implications

As demonstrated by an example, the results allow to predict the occurrence of visible defects on the edges of a part before manufacturing it with a given build orientation.

Originality/value

In literature, the geometric accuracy of additively manufactured parts is only related to surface features. The paper shows that the quality of edges depends on additional variables and causes to be carefully controlled by process choices.
Bonding quality and fracture analysis of polyamide 12 parts fabricated by fused deposition modeling
Authors: Li Hao , Zhang Shuai , Yi Zhiran , Li Jie , Sun Aihua , Guo Jianjun , Xu Gaojie
Published: October 2017

Purpose

This work aims to evaluate the influence of rheological properties of building materials on the bonding quality and ultimate tensile strength in the fused deposition modeling (FDM) process, through the investigation of parts printed by semi-crystalline and amorphous resins. Little information is currently available about the influence of the crystalline nature on FDM-printed part quality.

Design/methodology/approach

Semi-crystalline polyamide 12 and amorphous acrylonitrile butadiene styrene (ABS) were used to assess the influence of rheological properties on bonding quality and the tensile strength, by varying three important process parameters: materials, liquefier temperature and raster orientation. A fractography of both tensile and freeze-fractured samples was also investigated.

Findings

The rheological properties, mainly the melt viscosity, were found to have a significant influence on the bonding quality of fused filaments. Better bonding quality and higher tensile strength of FDM parts printed with semi-crystalline PA12, as compared with amorphous ABS, are suggested to be a result of higher initial sintering rates owing to the lower melt viscosity of PA12 at low shear rates. Near-full dense PA12 parts were obtained by FDM.

Originality/value

This project provides a variety of data and insight regarding the effect of materials properties on the mechanical performance of FDM-printed parts. The results showed that FDM technique allows the production of PA12 parts with adequate mechanical performance, overcoming the greatest limitation of a dependence on amorphous thermoplastics as a feedstock for the production of prototypes.
A hybrid machine learning approach for additive manufacturing design feature recommendation
Authors: Yao Xiling , Moon Seung Ki , Bi Guijun
Published: October 2017

Purpose

This paper aims to present a hybrid machine learning algorithm for additive manufacturing (AM) design feature recommendation during the conceptual design phase.

Design/methodology/approach

In the proposed hybrid machine learning algorithm, hierarchical clustering is performed on coded AM design features and target components, resulting in a dendrogram. Existing industrial application examples are used to train a supervised classifier that determines the final sub-cluster within the dendrogram containing the recommended AM design features.

Findings

Through a case study of designing additive manufactured R/C car components, the proposed hybrid machine learning method was proven useful in providing feasible conceptual design solutions for inexperienced designers by recommending appropriate AM design features.

Originality/value

The proposed method helps inexperienced designers who are newly exposed to AM capabilities explore and utilize AM design knowledge computationally.
Fundamental investigation of part properties at accelerated beam speeds in the selective laser sintering process
Authors: Lexow Matthias Michael , Drexler Maximilian , Drummer Dietmar
Published: October 2017

Purpose

Despite the recent progress in basic process understanding considering the selective laser sintering (SLS) of thermoplastics, several aspects of the mechanisms of the beam and powder interaction are not fully understood yet. Recent studies covered the correlation of mechanical properties and part density with the heating rate. The surface roughness of the test specimens was also considered but showed no distinct relation to the part mechanics. The purpose of this paper is to provide a new fundamental model for describing the decreasing mechanical properties with increasing beam speed.

Design/methodology/approach

While the dependence of mechanical properties with total energy input during exposure is well published, the correlation of the exposure speed with the degree of particle melt (DPM) is the subject of the present study. The DPM is accessible through differential scanning calorimetry measurements. Supporting the previously introduced method of the core-peak height, the interpretation via the core-peak area is proposed as a means to ascertain the melting behaviour for different processing conditions. Further support of the observations is given by x-ray computed tomography and microscopy which allows for a correlation with the respective porosity and inner structure of the parts.

Findings

The authors show a novel way of describing the decreasing mechanical properties with increasing speed of energy input by showing the dependence of the DPM on the heating rate during exposure.

Practical implications

The results offer an addition to the understanding considering the reliability and reproducibility of the SLS process.

Originality/value

The paper extends the existing models of the time-dependent material behaviour, which allows for the derivation of new efficient and stable process strategies.
The microstructure and mechanical properties of deposited-IN625 by laser additive manufacturing
Authors: Qin Lanlan , Chen Changjun , Zhang Min , Yan Kai , Cheng Guangping , Jing Hemin , Wang Xiaonan
Published: October 2017

Purpose

Laser additive manufacturing (LAM) technology based on powder bed has been used to manufacture complex geometrical components. In this study, IN625 superalloys were fabricated by high-power fiber laser without cracks, bounding errors or porosity. Meanwhile, the objectives of this paper are to systemically investigate the microstructures, micro-hardness and the precipitated Laves phase of deposited-IN625 under different annealing temperatures.

Design/methodology/approach

The effects of annealing temperatures on the microstructure, micro-hardness and the precipitated Laves phase were studied by optical microscope (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS), selected area electron diffraction (SAED), backscattered electron (BSE) imaging in the SEM and transmission electron microscopy (TEM), respectively. The thermal stability of the dendritic morphology about IN625 superalloys was investigated through annealing at temperatures range from 1,000°C to 1,200°C.

Findings

It is found that the microstructure of deposited-IN625 was typical dendrite structure. Besides, some Laves phase precipitated in the interdendritic region results in the segregation of niobium and molybdenum. The thermal stability indicate that the morphology of dendrite can be stable up to 1,000°C. With the annealing temperatures increasing from 1,000 to 1,200°C, the Laves phase partially dissolves into the γ-Ni matrix, and the morphology of the remaining Laves phase is changing from irregular shape to rod-like or block-like shape.

Research limitations/implications

The heat treatment used on the IN625 superalloys is helpful for knowing the evolution of microstructures and precipitated phases thermal stability and mechanical properties.

Practical implications

Due to the different kinds of application conditions, the original microstructure of the IN625 superalloys fabricated by LAM may not be ideal. So exploring the influence of annealing treatment on IN625 superalloys can bring theory basis and guidance for actual production.

Originality/value

This study continues valuing the fabrication of IN625 by LAM. It shows the effect of annealing temperatures on the shape, size and distribution of Laves phase and the microstructures of deposited-IN625 superalloys.
A comparative study of mechanical properties and machinability of wrought and additive manufactured (selective laser melting) titanium alloy – Ti-6Al-4V
Authors: Shunmugavel Manikandakumar , Polishetty Ashwin , Goldberg Moshe , Singh Rajkumar , Littlefair Guy
Published: October 2017

Purpose

The purpose of this paper is to study and compare the mechanical properties and machinability characteristics of additive manufactured titanium alloy Ti-6Al-4V with conventionally produced wrought titanium alloy,Ti-6Al-4V. The difference in mechanical properties such as yield strength, ultimate tensile strength, micro hardness, percentage of elongation and their effect on machinability characteristics like cutting forces and surface roughness are studied. It was found that higher strength and hardness of SLM Ti-6Al-4V compared to wrought Ti-6Al-4V owing to its peculiar acicular microstructure significantly affected the cutting forces and surface roughness. High cutting forces and low surface roughness were observed during machining of additive manufactured components compared to its wrought counterpart because of their difference in strength, hardness and ductility.

Design/methodology/approach

Mechanical properties like yield strength, ultimate tensile strength, hardness and percentage of elongation and machinability characteristics like cutting forces and surface roughness were studied for both wrought and additive manufactured Ti-6Al-4V.

Findings

Mechanical properties like yield strength, ultimate tensile strength and hardness were higher for additive manufactured components as compared to the wrought component. However additive manufactured components significantly lacked in ductility as compared to the wrought parts. Concerning machining, higher cutting forces and lower surface roughness were observed in additive manufactured Ti-6Al-4V compared to the wrought part as a result of differences in mechanical properties of these differently processed materials.

Originality/value

This paper, for the first time, discusses the machining capabilities of additive manufactured Ti-6Al-4V.
A new two-step adaptive direct slicing approach for bio-scaffolds in tissue engineering
Authors: Liu Wangyu , Li Mingke
Published: October 2017

Purpose

This paper aims to propose the new two-step adaptive direct slicing method for building bio-scaffold with digital micro-mirror device (DMD)-based MPμSLA systems.

Design/methodology/approach

In this paper, the authors proposed a new approach to directly slice a scaffold’s CAD model (i.e the three-dimensional model built by computer-aided design platforms) and save the slices’ data as BMP (bitmap, i.e. the data format used in DMD) files instead of other types of two-dimensional patterns as an intermediary. The proposed two-step strategy in this paper, i.e. a CAD model’s exterior surface and internal architecture were sliced, respectively, at first, and then assembled together to obtain one intact slice. The assembly process is much easier and convenient based on the slice data in BMP format. To achieve the adaptive slicing for both the exterior part and internal part, two new indices, the exterior surface-dominated index and internal architecture-dominated index, are, respectively, utilized as the error estimation indices. The proposed approach in this paper is developed on SolidWorks platform, but it can also be implemented on other platforms.

Findings

The authors found that the approach is not only more accurate but also more efficient by avoiding the repeated running of those inefficient rasterization programs. The approach is able to save computer resource and time, and enhance the robustness of slicing program, as well as is appropriate for the scaffolds’ model with internal pore architecture and external free-form surface.

Practical implications

Bio-scaffolds in tissue engineering require precise control over material distribution, such as the porosity, connectivity, internal pore architecture and external free-form surface. The proposed two-step adaptive direct slicing approach is a good balance of slicing efficiency and accuracy and can be useful for slicing bio-scaffolds’ models.

Originality/value

This paper gives supports to build bio-scaffold with DMD-based MPμSLA systems.
Optimization of parameters for SLS of WC-Co
Authors: Kumar Sanjay , Czekanski Aleksander
Published: October 2017

Purpose

WC-Co is a well-known material for conventional tooling but is not yet commercially available for additive manufacturing. Processing it by selective laser sintering (SLS) will pave the way for its commercialization and adoption.

Design/methodology/approach

It is intended to optimize process parameters (laser power, hatch spacing, scan speed) by fabricating a bigger part (minimum size of 10 mm diameter and 5 mm height). Microstructural analysis, EDX and hardness testing is used to study effects of process parameters. Optimized parameter is ascertained after fabricating 49 samples in preliminary experiment, 27 samples in pre-final experiment and 9 samples in final experiment.

Findings

Higher laser power gives rise to cracks and depletion of cobalt while higher scan speed increases porosity. Higher hatch spacing is responsible for delamination and displacement of parts. Optimized parameters are 270 W laser power, 500 mm/s scan speed, 0.04 mm layer thickness, 0.04 mm hatch spacing (resulting in energy density of 216 J/mm3) and 200°C powder bed temperature. A part comprising of small hole of 2 mm diameter, thin cylindrical pin of 0.5 mm diameter and thin wall of 2 mm width bent up to 30° angle to the base plate is fabricated. In order to calculate laser energy density, a new equation is introduced which takes into account both beam diameter and hatch spacing unlike old equation does. In order to calculate laser energy density, a new equation is formulated which takes into account both beam diameter and hatch spacing unlike old equation does. WC was not completely melted as intended giving rise to partial melting-type binding mechanism. This justified the name SLS for process in place of SLM (Selective Laser Melting).

Research limitations/implications

Using all possible combination of parameters plus heating the part bed to maximum shows limitation of state-of-the-art commercial powder bed fusion machine for shaping hardmetal consisting of high amount of WC (83 wt. per cent).

Practical implications

The research shows that microfeatures could be fabricated using WC-Co which will herald renewed interest in investigating hardmetals using SLS for manufacturing complex hard tools, molds and wear-resistance parts.

Originality/value

This is the first time micro features are successfully fabricated using WC-Co without post-processing (infiltration, machining) and without the help of additional binding material (such as Cu, Ni, Fe).
Friction and wear of the intervertebral disc endoprosthesis manufactured with use of selective laser melting process
Authors: Mróz Adrian Bartlomiej , Lapaj Lukasz , Wisniewski Tomasz , Skalski Konstanty , Leshchynsky Volf
Published: October 2017

Purpose

Orthopaedic implants, such as intervertebral disc endoprostheses (IDEs) are difficult to manufacture by means of conventional methods because of their complex shape. However, technologies developed in recent years, such as selective laser melting, could simplify this process. Although this method is attractive in both manufacturing and rapid prototyping of IDEs, little is known about their tribological performance. The functional aim of the work is to conduct a tribological evaluation of the ASTM F75 alloy after selective laser melting process and to investigate the viability of the technology in IDE design. The research aim was an explanation of the wear mechanism of bearing surfaces with respect to the reference material.

Design/methodology/approach

In this paper, the tribological test results of a lumbar IDE prototype fabricated by selective laser melting and forging is presented and compared. The endoprostheses were fabricated from commercially available ASTM F75 powder using a selective laser melting device. As a reference material, a forged ASTM F1537 LC alloy was used. Comparative wear and friction tests were carried out with the use of a unique spine simulator.

Findings

The obtained results confirm the viability of the selective laser technology in endoprosthesis design. Unfortunately, poorer tribological wear resistance of endoprostheses produced by means of selective laser melting (SLM) technology compared with that of the reference material calls into question the possibility of using these technologies in the manufacturing process of endoprosthesis' components exposed to tribological wear.

Originality/value

This paper presents the friction and wear behaviour of the lumbar IDE prototype. The tests were carried out in motion and loading conditions close to those we observe in the lumbar spine.
Low cost digital fabrication approach for thumb orthoses
Authors: Fernandez-Vicente Miguel , Escario Chust Ana , Conejero Andres
Published: October 2017

Purpose

The purpose of this paper is to describe a novel design workflow for the digital fabrication of custom-made orthoses (CMIO). It is intended to provide an easier process for clinical practitioners and orthotic technicians alike. It further functions to reduce the dependency of the operators’ abilities and skills.

Design/methodology/approach

The technical assessment covers low-cost three-dimensional (3D) scanning, free computer-aided design (CAD) software, and desktop 3D printing and acetone vapour finishing. To analyse its viability, a cost comparison was carried out between the proposed workflow and the traditional CMIO manufacture method.

Findings

The results show that the proposed workflow is a technically feasible and cost-effective solution to improve upon the traditional process of design and manufacture of custom-made static trapeziometacarpal (TMC) orthoses. Further studies are needed for ensuring a clinically feasible approach and for estimating the efficacy of the method for the recovery process in patients.

Social implications

The feasibility of the process increases the impact of the study, as the great accessibility to this type of 3D printers makes the digital fabrication method easier to be adopted by operators.

Originality/value

Although some research has been conducted on digital fabrication of CMIO, few studies have investigated the use of desktop 3D printing in any systematic way. This study provides a first step in the exploration of a new design workflow using low-cost digital fabrication tools combined with non-manual finishing.
Influence of processing parameters on creep and recovery behavior of FDM manufactured part using definitive screening design and ANN
Authors: Mohamed Omar Ahmed , Masood Syed Hasan , Bhowmik Jahar Lal
Published: October 2017

Purpose

The purpose of this paper is to investigate the effect of process parameters of fused deposition modelling (FDM) 3D printing process on viscoelastic responses (creep compliance and recoverable compliance) of FDM built parts using a novel experimental design technique.

Design/methodology/approach

As part of the process characterization, a recently developed class of three-level design methodology – definitive screening design (DSD) – was used in this study to fit a second-order polynomial regression model. Artificial neural network (ANN) was also used to determine the optimal process parameters to improve creep compliance and recoverable compliance. The relationship between layer thickness, air gap, raster angle, build orientation, road width, number of contours and creep performance of FDM fabricated part was thereafter established empirically. Scanning electron microscope (SEM) is used to examine and characterize the morphology of the structures for some samples.

Findings

This study found that the creep resistance of FDM-manufactured part is significantly influenced by layer thickness, air gap, raster angle and number of contours and it can be improved by optimizing the settings of the selected parameters. The relationship between FDM process parameters and creep properties was determined, with the best creep performance observed by using 0.127 mm of layer thickness, zero air gap, zero raster angle, build orientation of 17.188°, road width of 0.4572 mm and 10 contours. Finally, the result is verified by confirmation experiments. The results prove that a DSD is a very effective design in characterizing the influence of process parameters on creep properties of FDM-built part at the lowest cost.

Originality/value

The originality of this paper lies in characterizing and optimizing the effect of process parameters on creep performance of FDM manufactured part that has not been studied in all previous studies. The paper highlights, for the first time, how the application of DSD can overcome most of the limitations encountered in the conventional techniques. This study can be used as a guide to the different additive manufacturing users of various industries and the results provide a good technical database on how FDM process parameters influence the creep performance of manufactured parts.
Epidemiology and comorbidities of patients with chronic urticaria in Korea: A nationwide population‐based study
Authors: Kim Bo Ri , Yang Seungkeol , Choi Jee Woong , Choi Chong Won , Youn Sang Woong
Published: October 2017

Few population‐based studies have focused on the epidemiology and comorbidities of chronic urticaria (CU) or chronic spontaneous urticaria (CSU). The objective of this study was to obtain information on the epidemiology and comorbidities associated with CU and CSU in Korea. We conducted a cross‐sectional analysis using a national health insurance database. An algorithm based on the International Classification of Diseases, 10th revision, was used for the identification of patients with CU and CSU, and an age–sex adjusted logistic regression model was used to assess the risk of comorbidities in these patients. The average annual prevalence rates of CU and CSU during the 4‐year period between 2010 and 2013 were 3.08% and 1.40%, respectively. The prevalence rates of CU and CSU were higher in women than men (1:1.39 and 1:1.34, respectively) and peaked at 0–9 and 70–79 years, respectively. After adjustment for age and sex, the patients with CU and CSU were found to have a significantly higher prevalence rate of CU/CSU‐related diseases, compared with those without CU (mean adjusted odds ratio, 8.46; 95% confidence interval, 8.10–8.83). Allergic rhinitis, drug allergies, asthma, thyroid diseases and cancers were the most common comorbidities. Stomach, thyroid, liver and prostate cancers were the most prevalent cancers. This study provides large epidemiological data on the prevalence rates of CU and CSU, and their comorbidities, in Korea. Patients with CU and CSU impose a higher burden, in terms of specific comorbidities, than those without CU.
Effects of moisturizing skincare on skin barrier function and the prevention of skin problems in 3‐month‐old infants: A randomized controlled trial
Authors: Yonezawa Kaori , Haruna Megumi , Matsuzaki Masayo , Shiraishi Mie , Kojima Reiji
Published: October 2017

An effective newborn skincare protocol has not been established. We aimed to evaluate the effects of moisturizing skincare, including using lotion and reducing routine bathing. Our hypothesis was that moisturizing skincare would improve skin barrier function. This randomized controlled trial included 227 healthy Asian newborns between 1 week and 3 months old. We compared moisturizing skincare (bathing every 2 days and using lotion daily; intervention, n = 113) to daily bathing without lotion (control, n = 114). We assessed the skin barrier function (transepidermal water loss [TEWL], stratum corneum hydration [SCH], skin pH and sebum secretion) as a primary outcome at 3 months old. We also assessed the incidence of skin problems according to parents’ diary reports. Compared with the control, the intervention group had a lower face TEWL (mean ± standard deviation, 14.69 ± 7.38 vs 17.08 ± 8.26 g/m2 per h, P = 0.033), higher face SCH (60.38 ± 13.66 vs 53.52 ± 14.55, P = 0.001) and higher body SCH (58.89 ± 12.96 vs 53.02 ± 10.08, P < 0.001). Compared with the control, newborns in the intervention group had significantly lower rates of diaper dermatitis between birth and 1 month old (6.3% vs 15.9%, P = 0.022), and tended to have lower rates of body skin problems between 1 and 3 months (42.1% vs 55.2%, P = 0.064). Moisturizing skincare was effective for improving skin barrier function and preventing newborns’ diaper dermatitis. The results of our study may help parents make informed decisions about newborn skincare.
Human papillomavirus type 6/11 identified in an epidermoid cyst of the scrotum
Authors: Kawase Masaaki , Egawa Kiyofumi , Ishiji Takaoki , Nakagawa Hidemi
Published: October 2017

To date, epidermoid cysts associated with human papillomavirus (HPV) infection have been described mainly in palmoplantar locations, and have involved HPV types 60 and 57. In contrast, HPV‐6/11 is a major cause of condyloma acuminatum. Here, we report the case of a healthy 31‐year‐old man who presented to our clinic with a 1‐month history of a 1‐cm, reddish‐brown, cystic scrotal tumor with a punctum. The lesion was studied histologically, immunohistochemically and by DNA–DNAin situ hybridization. Histology revealed an epidermoid cyst with vacuolated keratinocytes with shrunken nuclei (koilocytes) in the cyst wall. Immunostaining was positive for HPV antigens and in situ hybridization revealed HPV‐6/11 DNA in the koilocytes. This is the first report of an HPV‐6/11‐associated epidermoid cyst in the anogenital skin of an immunocompetent individual.
Associations between anti‐melanoma differentiation‐associated gene 5 antibody and demographics, clinical characteristics and laboratory results of patients with dermatomyositis: A systematic meta‐analysis
Authors: Li Ju , Liu Yan , Li Yongsheng , Li Fang , Wang Kai , Pan Wenyou , Meng Deqian
Published: October 2017

Anti‐melanoma differentiation‐associated gene 5 (MDA5) antibody is a specific biomarker in patients with dermatomyositis (DM). Results from several studies that examined the relationship between anti‐MDA5 antibody and the demographics, clinical characteristics and laboratory results of DM patients have been conflicting. The purpose of this study was to identify the relationship, if any, of anti‐MDA5 antibody with demographics, clinical characteristics and laboratory results of DM patients. PubMed, Web of Science, Embase and the Cochrane Library databases were searched for studies without language restrictions conducted before 16 March 2017. Stata version 12.0 software was used to calculate pooled odds ratios or weighted mean differences and corresponding 95% confidence intervals to determine the relationship between anti‐MDA5 antibody and patient characteristics. Twenty studies comprising 1500 cases were included in this meta‐analysis. Anti‐MDA5 antibody was strongly associated with clinically amyopathic DM (CADM) and rapidly progressive interstitial lung disease (RPILD). Anti‐MDA5 antibody also increased the risk of developing eight characteristics comprising Gottron's sign or papules, mechanic's hand, V rash, skin ulcers, panniculitis, alopecia, arthritis/arthralgia and pneumomediastinum, but reduced the risk of muscle weakness, classic DM (CDM) and elevated creatine kinase (CK). Our meta‐analysis indicated that anti‐MDA5 antibody is related to muscle weakness, Gottron's sign or papules, mechanic's hand, V rash, skin ulcers, panniculitis, alopecia, arthritis/arthralgia, pneumomediastinum, RPILD, CDM, CADM and elevated CK in patients with DM.
Comparison of coastal phytoplankton composition estimated from the V4 and V9 regions of the 18S rRNA gene with a focus on photosynthetic groups and especially Chlorophyta
Authors: Tragin Margot , Zingone Adriana , Vaulot Daniel
Published: October 2017

We compared the composition of eukaryotic communities using two genetic markers (18S rRNA V4 and V9 regions) at 27 sites sampled during Ocean Sampling Day 2014, with a focus on photosynthetic groups and, more specifically green algae (Chlorophyta). Globally, the V4 and V9 regions of the 18S rRNA gene provided similar images of alpha diversity and ecological patterns. However, V9 provided 20% more OTUs built at 97% identity than V4. 34% of the genera were found with both markers and, of the remnant, 22% were found only with V4 and 44% only with V9. For photosynthetic groups, V4 and V9 performed equally well to describe global communities at different taxonomic levels from the division to the genus and provided similar Chlorophyta distribution patterns. However, at lower taxonomic level, the V9 dataset failed for example to describe the diversity of Dolichomastigales (Chlorophyta, Mamiellophyceae) emphasizing the lack of V9 sequences for this group and the importance of the reference database for metabarcode analysis. We conclude that in order to address questions regarding specific groups (e.g., a given genus), it is necessary to choose the marker based not only on the genetic divergence within this group but also on the existence of reference sequences in databases.
Chinese‐American parents’ perspectives about using the Internet to access information for children with special needs
Authors: Zeng Songtian , Cheatham Gregory A.
Published: October 2017

As the Internet contains large amounts of health‐ and education‐related information, it provides a potentially efficient and affordable format for directly reaching a large number of families with evidence‐based health‐ and education‐related information for their children with disabilities. Little is known, however, about Internet information‐seeking patterns for parents from culturally and linguistically diverse backgrounds. This study explored Chinese‐American parents’ perspectives about using the Internet to access health‐ and education‐related information for their children with disabilities. A survey was developed and conducted through a large community service centre in the western USA. Fifty‐two parents completed the survey; results suggest that challenges and barriers within the context of the Internet can limit parents from accessing meaningful and high‐quality information. Implications for research and practice are provided.