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1 – 10 of 162Sandra García-Bustos, Nadia Cárdenas-Escobar, Ana Debón and César Pincay
The study aims to design a control chart based on an exponentially weighted moving average (EWMA) chart of Pearson's residuals of a model of negative binomial regression in order…
Abstract
Purpose
The study aims to design a control chart based on an exponentially weighted moving average (EWMA) chart of Pearson's residuals of a model of negative binomial regression in order to detect possible anomalies in mortality data.
Design/methodology/approach
In order to evaluate the performance of the proposed chart, the authors have considered official historical records of death of children of Ecuador. A negative binomial regression model was fitted to the data, and a chart of the Pearson residuals was designed. The parameters of the chart were obtained by simulation, as well as the performances of the charts related to changes in the mean of death.
Findings
When the chart was plotted, outliers were detected in the deaths of children in the years 1990–1995, 2001–2006, 2013–2015, which could show that there are underreporting or an excessive growth in mortality. In the analysis of performances, the value of λ = 0.05 presented the fastest detection of changes in the mean death.
Originality/value
The proposed charts present better performances in relation to EWMA charts for deviance residuals, with a remarkable advantage of the Pearson residuals, which are much easier to interpret and calculate. Finally, the authors would like to point out that although this paper only applies control charts to Ecuadorian infant mortality, the methodology can be used to calculate mortality in any geographical area or to detect outbreaks of infectious diseases.
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Sandra García-Bustos, Joseph León and María Nela Pastuizaca
This research proposes a multivariate control chart, whose parameters are optimized using genetic algorithms (GA) in order to accelerate the detection of a change in the vector of…
Abstract
Purpose
This research proposes a multivariate control chart, whose parameters are optimized using genetic algorithms (GA) in order to accelerate the detection of a change in the vector of means.
Design/methodology/approach
This chart is based on a variation of the Hotelling T2 chart using a sampling scheme called generalized multiple dependent state sampling. For the analysis of performances of this chart, the out-of-control average run length (ARL) values were used for different scenarios. In this comparison, it was considered the classic Hotelling T2 chart and the T2 chart using the scheme called multiple dependent state sampling.
Findings
It was observed that the new chart with its optimized parameters is more efficient to detect an out-of-control process. Additionally, a sensitivity analysis was performed, and it was concluded that the best yields are obtained when the change to be considered in the optimization is small. An application in the resolution of a real problem is given.
Originality/value
In this research, a multivariate control chart is proposed based on the Hotelling T2 statistic but adding a sampling scheme. This makes this control chart more efficient than the classic T2 chart because the new chart not only uses the current information of the T2 statistic but also conditions the decision to consider a process as “in- control” on the statistic's previous information. The practitioner can obtain the optimal parameters of this new chart through a friendly program developed by the authors.
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Maria Rita Alaniz Porto, Vivian Sayuri Okina, Tatiana Colombo Pimentel, Sandra Garcia and Sandra Helena Prudencio
The purpose of this study was to evaluate beet and orange mixed juices added with lyophilized Lactobacillus acidophilus probiotic culture.
Abstract
Purpose
The purpose of this study was to evaluate beet and orange mixed juices added with lyophilized Lactobacillus acidophilus probiotic culture.
Design/methodology/approach
Two formulations of probiotic beet and orange mixed juices (1:1 e 1:2 v/v) were prepared, stored at 4°C for 28 days and were evaluated for probiotic survival, physicochemical stability, antioxidant activity and sensory acceptance. The probiotic culture was added in a lyophilized form and was not propagated in culture media or juice.
Findings
Physicochemical characteristics (pH, titratable acidity, total soluble solids and color) and antioxidant activity showed no undesirable alterations during storage. The number of probiotics followed established minimum requirement for probiotic foods (109 CFU/200mL) during the 28 days of storage. The juices showed good sensory acceptance and purchase intention, especially regarding the color of the product.
Practical implications
The beet and orange mixed juices are suitable carriers for L. acidophilus with a shelf life of at least 28 days at 4°C.
Originality/value
Direct addition of the probiotic culture could result in high probiotic survival in mixed juices, dispensing the propagation step.
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Fernanda Silva Farinazzo, Tiago Bervelieri Madeira, Maria Thereza Carlos Fernandes, Carolina Saori Ishii Mauro, Adriana Aparecida Bosso Tomal, Suzana Lucy Nixdorf and Sandra Garcia
The objective of this study was to evaluate the influence of Saccharomyces boulardii on the kinetics of fermentation for organic and conventional apple pulp and to verify the…
Abstract
Purpose
The objective of this study was to evaluate the influence of Saccharomyces boulardii on the kinetics of fermentation for organic and conventional apple pulp and to verify the effect of the antioxidant quercetin on the response to cellular oxidative stress.
Design/methodology/approach
The kinetic parameters, the content of phenolic compounds, the quantity of quercetin and the antioxidant activity were determined during the fermentation process. The effect of quercetin on cellular oxidative stress was also investigated.
Findings
The content of phenolic compounds, the antioxidant activity and the quercetin concentration were higher in the organic fermented apple pulp (ORG) than in the conventional fermented apple pulp (CON). However, both apple pulps were considered ideal substrates for the growth of S. boulardii, suggesting that they are potentially probiotic. After fermentation, the quercetin concentration in the ORG treatment and YPDQ treatment (YPD broth with 0.1 mg quercetin rhamnoside/mL) increased viability by 9%, while in the CON treatment generated there was an increase of 6% in viability, compared to the YPD control treatment (YPD broth).
Originality/value
The high concentration of quercetin in the organic apple pulp supports the proposal that quercetin reduces the oxidative stress mediated by reactive oxygen species through its antioxidant action on S. boulardii that have similarities to mammalian eukaryotic cells. These findings suggest that fermented organic apple pulp could be consumed as a potential non-dairy probiotic product.
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Marsilvio Lima Moraes Filho, Marli Busanello and Sandra Garcia
The purpose of this paper is to apply okara flour in the elaboration of a product, verifying the effect of the fermentation by Lactobacillus plantarum BG 112 on the…
Abstract
Purpose
The purpose of this paper is to apply okara flour in the elaboration of a product, verifying the effect of the fermentation by Lactobacillus plantarum BG 112 on the antihypertensive activity and to develop probiotic sauce with gums and low lipid content.
Design/methodology/approach
During the fermentation process, the inhibitory activity of angiotensin-converting enzyme (ACE) and production of organic acids were determined. The simplex-centroid mixture of guar gum, xanthan gum and pregelatinized cassava starch was used for studying the variables water holding capacity, viscosity and firmness. Counts of probiotics and in vitro survival of probiotics in simulated gastrointestinal conditions were made.
Findings
The fermented soymilk showed ACE inhibition capacity above 50 percent with 32 h of fermentation, increasing the levels of lactic acid and acetic acid progressively. Based on the regression analysis and response surfaces, the binary mixture with guar gum and xanthan was chosen as the most suitable for the formulation of the sauce, having over 30 days of storage counts above 8.5 log CFU.g−1 and above 6 log CFU.g−1 after simulation of gastrointestinal conditions. The global acceptance was 7.0 corresponding to the moderately liked.
Practical implications
The findings suggest that the sauce developed has been well accepted by potential consumers and can be incorporated into the diet and can result in health benefits for the consumer when regularly ingested. The fermentation process of soymilk promoted an increase in antihypertensive capacity. Despite the reduction in viable cell counts throughout storage, counts remained high in the product, having a high survival rate after exposure under simulated gastrointestinal conditions.
Originality/value
The use of okara flour in the diet is viable and helps to improve the nutritional composition of foods. The use of okara flour in sauce showed potential applicability and could be incorporated into different products. The fermentation process of soymilk with okara flour produces benefits beyond the sensorial characteristics. The elaborated probiotic sauce presented physical–chemical and microbiological stability throughout the storage, being an alternative for people with food restrictions.
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Marli Busanello, Marsilvio Lima De Moraes Filho, Karla Bigetti Guergoletto and Sandra Garcia
This paper aims to study the effect of addition of green banana flour (GBF) in skim milk, provides a nutritional and functional contribution to this matrix when added. They have…
Abstract
Purpose
This paper aims to study the effect of addition of green banana flour (GBF) in skim milk, provides a nutritional and functional contribution to this matrix when added. They have biological compounds like resistant starch, phenolic compounds, antioxidant compounds and others. The skim milk containing 1.08 per cent of GBF was chosen after a central composite rotational design and response surface methodology. The response variable was the growth of Lactobacillus plantarum (LP) and Lactobacillus helveticus (LH).
Design/methodology/approach
During the fermentation process, the antioxidant activity, plasmid DNA protection capacity, proteolytic activity and inhibitory activity of angiotensin-converting enzyme (ACE) of the fermented milk was determined.
Findings
All variables were influenced by the fermentation time. The antioxidant activity evaluated by the ABTS radical presented values of 0.83 ± 0.04 µM Trolox.mL−1 and 0.79 ± 0.02 µM Trolox.mL−1, respectively, for the fermented LP and LH. The extracts fermented by L. plantarum and L. helveticus were able to inhibit the oxidation of plasmidial DNA. The proteolytic activity was higher in the fermented with LH (1.16 ± 0.03) than in the fermented with LP (0.71 ± 0.02). The ACE inhibitory activity was higher in the fermented LH (59.01 per cent) than in the fermented LP (54.45 per cent).
Originality/value
Fermented milk with 1.08 per cent GBF presented positive results in the analyzed variables and could be studied commercially as a functional food alternative.
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Meliha Handzic, John S. Edwards, Sandra Moffett, Alexeis Garcia-Perez, Aino Kianto and Ettore Bolisani
The purpose of this paper is to discuss key aspects of knowledge management (KM) education in response to challenges posed by the necessity to improve KM as a discipline and an…
Abstract
Purpose
The purpose of this paper is to discuss key aspects of knowledge management (KM) education in response to challenges posed by the necessity to improve KM as a discipline and an established professional field.
Design/methodology/approach
The paper is based on a systematic review of the current literature. This review was used as input in a recent panel held at the 2016 International Conference on Knowledge Management (ICKM). The paper brings together current literature with thought-provoking panelists’ presentations and subsequent debates with the audience.
Findings
KM education from the “why, what, who, where and when” perspectives were first addressed and analyzed, and the end result was a reflection on “how” to approach KM education in the future.
Research limitations/implications
This paper effectively underlines that, KM being a relatively new phenomenon, there is no clear consensus about roles that KM employees should play in an organization, what KM competencies and skills are needed, and where and when these should be obtained. Broad guidelines on how to approach KM education in the future may serve as a basis for further research.
Practical implications
The study provides suggestions on how to place KM in adult education.
Originality/value
The paper tackles the research questions through an innovative combination of a systematic literature review and a panel discussion on the topic of KM and education. Overall, the paper provides a fresh view of the state of the art of knowledge and research on the topic and also shows the common vision of a group of KM researchers and educators.
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Successful performance and execution of construction projects depend highly on a good project control system capable of tracking and reporting project status on a desired time…
Abstract
Purpose
Successful performance and execution of construction projects depend highly on a good project control system capable of tracking and reporting project status on a desired time interval. The purpose of this paper is to propose such a control system by integrating spreadsheet and Visual Basic for Application to produce a customized tracking system for Pipeline Relocation Programs under Engineering, Procurement and Construction Management (EPCM) contracts.
Design/methodology/approach
The project status reporting system (PSRS) proposed here was developed to produce a single page summary report that would include scope information, financial status, descriptive status updates and top-level task schedules. This information is retrieved from various sources and transformed further utilizing specific formulas and algorithm needed to compute the budget and schedule status of the pipe relocation project. A practical case study is used to demonstrate its unique application.
Findings
The system has successfully integrated project finance and schedule information into a central control hub. Financial and schedule performance of a project is tracked and monitored by the PSRS automatically.
Originality/value
The proposed system utilizes the powerful computing capability of MS Excel and the user-friendly VBA programming tool to customize the reporting needs of a project and program environment. The proposed system, whose functionality has been validated by the intended users, tries to achieve a balance between simplicity, accuracy and effectiveness for the flow of information at a much lower cost compared to the other readily available project control software.
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Oscar Robayo-Pinzon, Sandra Rojas-Berrio, Patricia Núñez-Gómez, Blanca Miguélez-Juan and Ligia García-Béjar
The use of mobile devices by children and adolescents is increasing significantly; therefore, it is relevant to research the level of advertising literacy (AL) of parents who act…
Abstract
Purpose
The use of mobile devices by children and adolescents is increasing significantly; therefore, it is relevant to research the level of advertising literacy (AL) of parents who act as mediators between children and mobile advertising. This study aims to explore the conceptual, moral and attitudinal dimensions of AL and its relationship with different styles of parental control.
Design/methodology/approach
A cross-sectional survey was applied simultaneously to a sample of parents with children between 5 and 16 years old in three Spanish-speaking countries: Mexico, Spain and Colombia. Participants from the three countries were recruited via online social media networks and were asked to fill in an online survey. A questionnaire, which has been adapted from previous literature to suit the mobile advertising context and the population of interest, was designed. Cross-country samples of varying sizes, with a predetermined quota of 200 participants for each country, were used. The total sample consisted of 1,454 participants.
Findings
Four factors of mobile AL were found, which, to a greater extent, correspond to the dimensions of AL proposed in the literature. The following are the dimensions that were identified: cognitive, moral, attitudinal and an emerging factor is known as “children’s perceived mobile AL.” Differences in parents’ perceived knowledge of mobile advertising, parental control styles and AL levels in the three countries were identified. Parents with an authoritative style were identified to have more knowledge than those with an indulgent style. Differences were also identified between countries concerning the amount of exposure that children have to mobile advertising, while no significant differences were found in the moral dimension.
Practical implications
Marketing practitioners and public policymakers must consider that parents differ in some dimensions of AL. Parents also seem to lack adequate knowledge about the advertising tools available to announcers that affect children and adolescents in a mobile communication environment. Therefore, government agencies should consider developing mobile digital media literacy programs for parents.
Originality/value
This paper explores the dimensions of AL applied to the mobile context and identifies the level of parental mobile AL in three Spanish-speaking countries, as well as the differences between these sub-samples concerning parental mobile AL profiles and parental control styles, thus expanding the literature on AL with a cross-cultural approach.
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