Cristina Rodríguez‐Rieiro, Paz Rodríguez Pérez, Susana Granado de la Orden, Mercedes Moreno Moreno, Ana Chacón García and Amaya Sánchez‐Gómez
The paper's purpose is twofold: to provide a predictive model for estimating in‐hospital mortality rates after coronary artery bypass grafting (CABG) in Spanish autonomous regions…
Abstract
Purpose
The paper's purpose is twofold: to provide a predictive model for estimating in‐hospital mortality rates after coronary artery bypass grafting (CABG) in Spanish autonomous regions (AR) after adjusting relevant factors; and to determine whether there is a difference between expected and observed mortality rates.
Design/methodology/approach
All patients registered in a minimum basic data set (MSBD) undergoing CABG between 2000 and 2004 were selected. After bivariate analysis to explore associations between in‐hospital death and other variables, a multivariate analysis using logistic regression was conducted. The predictive model was evaluated using calibration and discrimination techniques. Standardized mortality ratios by AR were calculated.
Findings
The expected Spanish in‐hospital mortality rate after CABG was 7.68 and the observed rate was 7.69 deaths per 100 operations. Discrimination obtained with the model resulted in an area under the curve of 0.70 (95 per cent CI, 0.69‐0.71). When each AR's mortality rate is calculated and compared with the observed rate, some ARs present an observed mortality rate higher or lower than the expected rate according to adjusted variables in the model.
Research limitations/implications
The MSBD registry does not contain patients' critical data, such as arterial damage severity, or in which hospital procedures were performed.
Practical implications
There are factors related to individual patient variation, financial resources or healthcare quality in different ARs, which should be investigated in follow‐up studies.
Originality/value
The paper shows that, although the global expected mortality rate is almost the same as the observed Spanish mortality rate, this similarity disappears when AR rates are compared.
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Susana Granado de la Orden, Cristina Rodríguez‐Rieiro, Amaya Sánchez‐Gómez, Ana Chacón García, Tomás Hernández‐Fernández, Ángel Abad Revilla, Dolores Vigil Escribano and Paz Rodríguez Pérez
This paper aims to explore lot quality assurance sampling (LQAS) applicability and usefulness in the evaluation of quality indicators in a hospital emergency department (ED) and…
Abstract
Purpose
This paper aims to explore lot quality assurance sampling (LQAS) applicability and usefulness in the evaluation of quality indicators in a hospital emergency department (ED) and to determine the degree of compliance with quality standards according to this sampling method.
Design/methodology/approach
Descriptive observational research in the Hospital General Universitario Gregorio Marañón (HGUGM) emergency department (ED). Patients older than 15 years, diagnosed with dyspnoea, chest pain, urinary tract colic or bronchial asthma attending the HGUGM ED from December 2005 to May 2006, and patients admitted during 2005 with exacerbation of chronic obstructive pulmonary disease or acute meningitis were included in the study. Sample sizes were calculated using LQAS. Different quality indicators, one for each process, were selected. The upper (acceptable quality level (AQL)) and lower thresholds (rejectable quality level (RQL)) were established considering risk α=5 per cent and β=20 per cent, and the minimum number of observations required was calculated.
Findings
It was impossible to reach the necessary sample size for bronchial asthma and urinary tract colic patients. For chest pain, acute exacerbation of chronic obstructive pulmonary disease, and acute meningitis, quality problems were detected. The lot was accepted only for the dyspnoea indicator.
Originality/value
The usefulness of LQAS to detect quality problems in the management of health processes in one hospital's ED. The LQAS could complement traditional sampling methods.
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Miguel Ángel Caminero, Ana Romero Gutiérrez, Jesús Miguel Chacón, Eustaquio García-Plaza and Pedro José Núñez
The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material wastage. In…
Abstract
Purpose
The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material wastage. In this study, 316L stainless-steel metal filled filaments were used to print metal parts using the extrusion-based fused filament fabrication (FFF) approach. The purpose of this study is to assess the effects of common FFF printing parameters on the geometric and mechanical performance of FFF manufactured 316L stainless-steel components.
Design/methodology/approach
The microstructural characteristics of the metal filled filament, three-dimensional (3D) printed green parts and final sintered parts were analysed. In addition, the dimensional accuracy of the green parts was evaluated, as well as the hardness, tensile properties, relative density, part shrinkage and the porosity of the sintered samples. Moreover, surface quality in terms of surface roughness after sintering was assessed. Predictive models based on artificial neural networks (ANNs) were used for characterizing dimensional accuracy, shrinkage, surface roughness and density. Additionally, the response surface method based on ANNs was applied to represent the behaviour of these parameters and to identify the optimum 3D printing conditions.
Findings
The effects of the FFF process parameters such as build orientation and nozzle diameter were significant. The pore distribution was strongly linked to the build orientation and printing strategy. Furthermore, porosity decreased with increased nozzle diameter, which increased mechanical performance. In contrast, lower nozzle diameters achieved lower roughness values and average deviations. Thus, it should be noted that the modification of process parameters to achieve greater geometrical accuracy weakened mechanical performance.
Originality/value
Near-dense 316L austenitic stainless-steel components using FFF technology were successfully manufactured. This study provides print guidelines and further information regarding the impact of FFF process parameters on the mechanical, microstructural and geometric performance of 3D printed 316L components.
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Miguel Ángel Caminero, Ana Romero, Jesús Miguel Chacón, Pedro José Núñez, Eustaquio García-Plaza and Gloria Patricia Rodríguez
Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for laser-based…
Abstract
Purpose
Fused filament fabrication (FFF) technique using metal filled filaments in combination with debinding and sintering steps can be a cost-effective alternative for laser-based powder bed fusion processes. The mechanical behaviour of FFF-metal materials is highly dependent on the processing parameters, filament quality and adjusted post-processing steps. In addition, the microstructural material properties and geometric characteristics are inherent to the manufacturing process. The purpose of this study is to characterize the mechanical and geometric performance of three-dimensional (3-D) printed FFF 316 L metal components manufactured by a low-cost desktop 3-D printer. The debinding and sintering processes are carried out using the BASF catalytic debinding process in combination with the BASF 316LX Ultrafuse filament. Special attention is paid on the effects of build orientation and printing strategy of the FFF-based technology on the tensile and geometric performance of the 3-D printed 316 L metal specimens.
Design/methodology/approach
This study uses a toolset of experimental analysis techniques [metallography and scanning electron microcope (SEM)] to characterize the effect of microstructure and defects on the material properties under tensile testing. Shrinkage and the resulting porosity of the 3-D printed 316 L stainless steel sintered samples are also analysed. The deformation behaviour is investigated for three different build orientations. The tensile test curves are further correlated with the damage surface using SEM images and metallographic sections to present grain deformation during the loading progress. Mechanical properties are directly compared to other works in the field and similar additive manufacturing (AM) and Metal Injection Moulding (MIM) manufacturing alternatives from the literature.
Findings
It has been shown that the effect of build orientation was of particular significance on the mechanical and geometric performance of FFF-metal 3-D printed samples. In particular, Flat and On-edge samples showed an average increase in tensile performance of 21.7% for the tensile strength, 65.1% for the tensile stiffness and 118.3% for maximum elongation at fracture compared to the Upright samples. Furthermore, it has been able to manufacture near-dense 316 L austenitic stainless steel components using FFF. These properties are comparable to those obtained by other metal conventional processes such as MIM process.
Originality/value
316L austenitic stainless steel components using FFF technology with a porosity lower than 2% were successfully manufactured. The presented study provides more information regarding the dependence of the mechanical, microstructural and geometric properties of FFF 316 L components on the build orientation and printing strategy.
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Barbara de Lima Voss, David Bernard Carter and Bruno Meirelles Salotti
We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in…
Abstract
We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.
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Ana P. Valerga Puerta, S.R. Fernandez-Vidal, Moises Batista and F. Girot
This paper aims to study the interfacial and interlayer bonding of Polylactic acid parts manufactured by fused deposition modelling. Different layer thicknesses are analysed in…
Abstract
Purpose
This paper aims to study the interfacial and interlayer bonding of Polylactic acid parts manufactured by fused deposition modelling. Different layer thicknesses are analysed in the manufacture of these pieces and the lack of material associated with this parameter is verified. The influence of the immersion of these parts in different solvents is also studied, as they are increasingly used in the improvement of the surface finish. Tomography results are also obtained in which the increase in density of the parts subjected to these treatments is demonstrated.
Design/methodology/approach
The material used in this study is a 1.75-mm diameter polylactic acid (PLA) filament from fused filament fusion world. Monolayer and multilayer samples have been manufactured. The manufactured parts were subjected to solvent immersion for a period of 60 s. The solvents used are chloroform (CHCl3), dichloromethane (CH2Cl2), tetrahydrofuran (C4H8O) and ethyl acetate (C4H8O2). The pieces were then dried for 48 h. The interior of the samples was evaluated by two techniques: microscopy and tomography.
Findings
With this study, it has been observed that the thickness of the layer affects the porosity interfacial to a greater extent than in the interlayer, causing the increase in porosity as this thickness is increased.The impact of different chemical treatments (immersions in different solvents) on the internal quality of the parts has been evaluated. All the solvents analysed soften the surface as they cause the softening of the material and its possible redistribution. In the interior, however, they affect in a lighter way. The retention of solvents in the porosity of the pieces is also checked, especially pronounced in the areas close to the surface. Finally, changes are observed in the density of the pieces, related to the partial crystallization of the samples.
Originality/value
All that has been studied shows that the application of chemical post-processes not only affects the surface texture of the parts, or the less studied mechanical properties, but also affects the interfacial union of the parts in a very different way. This is the first study carried out on this aspect with polylactic acid (PLA) and post-processing methods.
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Jesús Martínez-Navarro, Fernando Campayo-Sánchez and Liudmila Ostrovskaya Fedorova
This study aims to appraise the historical evolution of tourism research focused on Spain. Firstly, an analysis was conducted to assess the production and impact of research…
Abstract
Purpose
This study aims to appraise the historical evolution of tourism research focused on Spain. Firstly, an analysis was conducted to assess the production and impact of research within this domain. Secondly, scientific mapping, specifically through co-word analysis, was used to identify and explore the principal research themes and their evolution in the field.
Design/methodology/approach
A historical approach was adopted in this study, using 1,100 bibliographic records obtained from the Scopus database. Science mapping was then conducted through co-word analysis of bibliographic data.
Findings
The results of the performance analysis provide insights into the volume, evolution and impact of the scientific documents published within the research area under investigation. Moreover, by adopting a longitudinal approach, science mapping through co-word analysis enables the definition of the intellectual structure within this research domain. In this regard, the main research themes are identified, conceptually assessed, and their evolution is examined across three distinct window periods: an initial research period (1972–2002), a growing research period (2003–2012) and a consolidation period (2013–2022).
Originality/value
The study provides a state-of-the-art position on tourism research related to Spain thus guiding future studies in the area. Furthermore, this study provides a comprehensive “snapshot” of the historical progression of tourism research in Spain, capturing the emblematic aspects that have emerged within the area over the investigated time period.
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Minhajul Islam Ukil, Muhammad Shariat Ullah, K.M. Zahidul Islam, B M Razzak, George Saridakis and Saeed M Alamoudi
Entrepreneurship is often seen as a journey filled with emotions. However, the literature lacks an empirical framework for how emotions relate to entrepreneurial intention…
Abstract
Purpose
Entrepreneurship is often seen as a journey filled with emotions. However, the literature lacks an empirical framework for how emotions relate to entrepreneurial intention. Drawing upon an extended view of the theory of planned behavior (TPB) that emotions may have a direct and/or indirect effect on intention, this study investigates how positive and negative emotions influence entrepreneurial intention.
Design/methodology/approach
Applying the partial least squares structural equation model in SmartPLS 4, the hypothesized relationships were examined with a sample of 553 survey respondents from Bangladesh during and after the COVID-19 pandemic. All respondents were Bangladeshi nationals.
Findings
This study found that positive emotions have both significant direct and indirect effects, whereas negative emotions only have a significant indirect effect on entrepreneurial intention through personal attitudes and perceived behavioral control. Contrary to the extant understanding, this study found no significant relationship between subjective norms and entrepreneurial intention. Notably, the results did not vary between the during- and post-COVID-19 periods.
Originality/value
This study adds valuable insights into the relatively unexplored field of entrepreneurial intention by extending the TPB and demonstrating how emotions relate to entrepreneurial intention.