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The purpose of this paper is to investigate the application of the element‐free Galerkin (EFG) method to the simulation of metal forming processes and to propose a strategy to deal with volumetric locking problem in this context.

The J₂ elastoplastic material model, employed in the work, assumes a multiplicative decomposition of the deformation gradient into an elastic and a plastic part and incorporates a non‐linear isotropic hardening response. The constitutive model is written in terms of the rotated Kirchhoff stress and the logarithmic strain measure. A Total Lagrangian formulation of the problem is considered in order to improve the computational performance of the proposed algorithm. The imposition of the essential boundary conditions and also of the unilateral contact with friction condition are made by the application of the Augmented Lagrangian method. Here, aspects related to the volumetric locking are investigated and an F‐bar approach is applied.

The results show that the proposed approach presents no volumetric locking phenomenon when using the mean dilation approach. Moreover, differently from finite element approximations, no hour‐glass instabilities in the deformation pattern are observed, avoiding in this way the need to devise additional stabilization procedures in the proposed procedure.

This paper demonstrates the implementation and validation of the mean dilation approach, in the scope of the EFG, which was successful in coping with the volumetric locking phenomena and presented no hour‐glass instabilities in the problem cases considered in this work.

The purpose of this paper is to investigate the approximation performance of a family of piecewise rational polynomial shape functions, which are enriched by a set of monomials of order p to obtain high order approximations. To numerically demonstrate the features of the enriched approximation some examples on the mechanical elastic response and free‐vibration of axisymmetric plates and shells are carried out.

The global approximation is based on a particular family of weight function, which is defined on the parametric domain of the element, ξ∈[−1,1], resulting in shape functions with compact support, which have regularity C₀^k,k=0,2,4… in the global domain Σ. The PU shape functions are enriched by a set of monomials of order p to obtain high order approximation spaces.

Based on the numerical results of elastic axisymmetric plates and shells, it is demonstrated that the proposed methodology produces satisfactory results in terms of keeping the ill‐conditioning of the system of equations under accepted levels. Comparisons are established between linear and Hermitian shape functions showing similar results. The observed results for the free‐vibration problem of plates and shells show the potential of the proposed approximation space.

In this paper the formulation is limited to the modeling of axisymmetric plate and shell problems. However, it can be applied to model other problems where the high regularity of the approximation is required.

The paper presents an alternative approach to construct partition of unity shape functions based on a particular family of weight function.

The aim of this paper is to determine chemical and sensory differences of between craft and industrial/or commercial beers. Beer market is nowadays booming and consumers are in the search of new and healthier products.

Here, commercial and craft beers were chemically analyzed and sensory evaluated. Chemical analysis included pH, bitterness, color, total polyphenol content and antioxidant activity. Likewise, 40 sensory descriptors were evaluated by trained panelists, including visual, olfactory and gustatory attributes. In addition, an electronic nose (e-nose) was tested to determine its suitability to discriminate beer type and/or style according to their volatiles profile.

Craft beers presented higher values of color, bitterness and antioxidant activity when compared to commercial beers. Sensory descriptors showed craft beers to be associated with the highest scores in visual, olfactory and gustatory descriptors. Data from e-nose explained 97% of the total variability of the volatile compounds in the analyzed beers, indicating the suitability of this device to discriminate beer types.

Results are of interest for design of marketing and selling techniques for craft brewery managers. In addition, cheap and easy-managing device as e-nose resulted in a valuable tool to monitoring beer quality.

The purpose of this paper is to provide a systematic and comprehensive review of the existing literature on the determinants of firms reporting practices.

Following a systematic method, the sample literature of 135 studies was collected from the Scopus database. These studies were evaluated in terms of the theoretical lenses applied in the literature, yearly trend, regional distribution, research settings and prior studies finding to provide some recommendations for further research.

The investigation revealed that the literature was more interested in the agency theory in investigating the drivers of voluntary reporting such as company size, age, leverage, liquidity, profitability, corporate governance and ownership structure. Although firm-specific determinants were the most examined in the previous studies, however, the result is still inconclusive. Also, limited work was found on the country-related factors, while internal audit impact has yet to be explored.

Being the first of its kind, this research provides a comprehensive review of the current research landscape on the drivers of environmental or social disclosure and highlights several interesting opportunities for future research.

The objective of this study was to evaluate the technical-economic process efficiency of obtaining simultaneous lipo-soluble (LSF) and water-soluble (WSF) fractions from annatto seeds.

The batches of annatto seeds were submitted to the refrigerated solid-liquid extraction process in four stages: pre-extraction, aqueous extraction, separation by decantation and filtration. After that, LSF and WSF from annatto seeds were obtained. The process efficiency and the quality of LSF and WSF were analyzed in terms of average yield and bioactive compounds (bixin, norbixin, phenolics and flavonoids) and their antioxidant and antimicrobial activities. Furthermore, they were economically evaluated in terms of costs of manufacturing and profitability parameters.

The process was efficient in terms of overall average yield (LSF = 8.68% and WSF = 2.76%) (w/w) and in terms of quality, mainly with higher average yields of bixin (82.34% in LSF) and norbixin (29.59% in WSF) (w/w). The concentration of bioactive compounds in the fractions promoted an increase in inhibiting free radicals (DPPH* and ABTS*+) and in the ferric-reducing power (FRAP). LSF showed a minimum inhibitory concentration of 0.06 mg mL-1 for S. aureus and 0.13 mg mL-1 for S. Typhimurium and S. Enteritidis. The lowest manufacturing costs were obtained for the LSF due to its higher extraction yield compared to the WSF. Plants on an industrial scale of 100 and 1000 L were considered economically viable, with a return on investment of 5 and 2 years.

Thus, fractions (WSF and LSF) can be applied as natural additives, as sources of bioactive compounds for nutraceutical and/or pharmaceutical, and in the development of other innovative processes. These results have practical applicability for pharmaceutical and food industry.

1. Green processing of annatto seeds obtains fractions rich in antioxidant compounds.

2. Efficiently presents a high yield of bixin and other bioactive compounds.

3. Effective in concentrating compounds that inhibit microbial growth.

4. Fractions are more accessible sources of bioactive compounds for isolation.

5. Cost of manufacturing (COM) and profitability are studied.

Green processing of annatto seeds obtains fractions rich in antioxidant compounds.

Efficiently presents a high yield of bixin and other bioactive compounds.

Effective in concentrating compounds that inhibit microbial growth.

Fractions are more accessible sources of bioactive compounds for isolation.

Cost of manufacturing (COM) and profitability are studied.

The purpose of this paper is to investigate the challenges that companies could face over time when dealing with sustainability reporting (SR) and focusses on potential mechanisms they may adopt to cope with them.

The investigation is conducted adopting the theoretical framework proposed by Baret and Helfrich (2018) and using a longitudinal case study.

The authors found that the challenges that gradually arose induced the evolution of SR. Dissemination, employees’ involvement, managerial commitment and routinization/institutionalization of reporting practices appeared to be useful mechanisms to face the related challenges. Conversely, the authors found that stakeholders’ engagement scarcely affected SR. Furthermore, the legislation impacted the extent and quality of disclosed contents and fostered the standardization of the reporting process.

In analysing how Estra faced SR challenges, this paper emphasizes the mechanisms that can be used to properly manage them, in a gradual and holistic way. Hence, this study offers a useful example for companies approaching SR for the first time.

The authors adopt a holistic theoretical perspective providing evidence on how SR development within a company depends on the continuous and integrated management of its multiple challenges, also suggesting that its interdependencies with the definition and execution of sustainability should be exploited.

This paper studies the Digital Service Innovation (DSI) concept by systematically reviewing earlier studies from various scholarly communities. This study aims to recognize how recent advances in DSI literature from different research streams complement and can be incorporated into the growing digital servitization literature to define better and understand DSI.

After systematically identifying 123 relevant articles, this study employed complementary methods, such as author bibliographic coupling, linguistic text mining/textual analysis and qualitative content analyses.

This paper first maps the intellectual structure and boundaries of the DSI-related communities and qualitatively assesses their characteristics. These communities are (1) Innovation for digital servitization, (2) Service innovation in the digital age and (3) Adoption of novel e-services enabled by information system development. Next, the composition of the DSI concept is examined and depicted to comprehend the notion's critical dimensions. The findings discuss the range of theories and methods in the existing research, including antecedents, processes and outcomes of DSI.

This study reviews, extends the understanding of origins and critically evaluates DSI-related research. Moreover, the paper redefines and clarifies the structure and boundaries of the DSI-concept. In doing so, it elaborates on the substance of DSI and identifies the essential themes for its understanding and conceptualization. Thus, the study helps the future development of the concept and allows knowledge accumulation by bridging adjacent research communities. It helps researchers and managers navigate the foggy emerging research landscape.

The purpose of this paper is to carry out a meta-regression analysis upon the literature that examines the relationship between family firms and financial performance.

Information of publication and study characteristics from 61 primary studies, comprising 726 size effects was collected. In particular, three leading factors highlighted in narrative literature reviews analyzed were: the financial performance measures, the family–firm definitions and the estimation methodologies.

Overall, a positive relationship between family involvement and financial performance was found. A series of results, those linked to return on assets (ROA) – earnings before interest, taxes, depreciation and amortization (EBITDA), suggest positive publication bias from family definition and negative publication bias when OLS is used. Tobin’s Q estimates show no linkage to certain traits and aspects of the research process.

Existing literature review and meta-analysis studies show not concluding results on the family effect upon firm performance. The meta-regression analysis used in this paper allows to examine simultaneously effect size and publication bias. The latter effect is particularly salient in the approach and findings, and not present in previous studies.

Llevar a cabo un análisis de meta-regresión a la literatura que examina la relación entre firmas familiares y desempeño financiero.

Se usa la información de la publicación y características del estudio de 61 estudios primarios, que incluyen 726 estimaciones. Se examinan tres elementos principales de esta literatura: (i) medidas de desempeño financiero, (ii) definición de firma familiar, y (iii) metodología de estimación.

Se establece una relación positiva entre involucramiento familiar y desempeño financiero. Las estimaciones que examinan ROA-EBITDA sugieren sesgo positivo de publicación. Las estimaciones que utilizan estimación de Mínimos Cuadrados Ordinarios sugieren un sesgo negativo de publicación. Las estimaciones que examinan la Q de Tobin, no sugieren relación con las características de los estudios o de la investigación.

Los estudios de meta-análisis existentes sobre esta literatura no ofrecen resultados concluyentes del efecto de las firmas familiares y desempeño financiero. El método de meta-regresión permite examinar simultáneamente el efecto entre las variables y la posible existencia de sesgo de publicación. La indagación de este último es de particular interés y no se encuentra en otros estudios.

Despite the rapid growth of the World Wide Web in the last several years few studies have appeared in the literature assessing Web sites’ efficacy. This paper provides an original Web Assessment Index, focused on four categories: accessibility, speed, navigability and content. The scoring mechanism is explained and the index is applied to assess the Web sites of all Spanish universities. Finally, conclusions and implications derived from this study are presented.

The purpose of this paper is to show how the intervention mapping (IM) protocol could be applied to the development of two school‐based interventions. It provides an extensive description of the development, implementation and evaluation of two interventions which aimed to increase fruit and vegetable (F&V) consumption among primary school children.

The paper describes how information drawn from relevant literature and theory, as well as additional data collected from primary school children, their parents and teachers, were applied to the development, implementation and evaluation of the interventions. The IM protocol consists of five steps: defining proximal program objectives; applying methods and strategies for behavioural change; creating a program plan; preparing program implementation; and evaluation. An extensive assessment of the perceived health problem was conducted prior to beginning step 1 of IM.

Application of the protocol resulted in two school‐based interventions aimed at making F&V consumption habitual: a free F&V distribution program; and a multi‐component, age‐specific program consisting of a classroom curriculum and parental involvement.

The matrices presented can provide health educators with a foundation for the development of future dietary interventions for children.

By providing a detailed description of the application of the IM, it was shown that the protocol can be used as a practical aid for the development of planned health promotion interventions. It proved to be an effective means for making well‐considered choices in every step of program development and implementation.