Lean Six Sigma Approach to Improve the Production Process in the Mould Industry: a Case Study

Purpose: The purpose of this article is to explore the optimization of internal process is assumed as a critical factor to be capable of answering to the moulds industries. Consequently, it has been considered essential to adopt high-valued methodologies to support tooling industry in order to achieve global competitive advantages. For that purpose, this work aims to apply LEAN principles and techniques to support mould design and manufacturing processes. Methodology/Approach: The methodology used was based on PDCA/DMAIC, with the following stages: Define, Measure, Analyze, Improve and Control. For each stages was taken some of Lean Six Sigma techniques, such as Continuous Improvement, Value Stream Mapping, Pareto analysis and Overall Equipment Effectiveness. Findings: This study results was revealed that there are many areas on the organizations in the Mould Industry, when they utilize otimizations tools obtain hugt successes. With the Pareto analysis was carried out to show that events that contributes the most to the stops. The results were: unavailability of the operator (16.4%), programming the machine (14.4%) and tool exchange (12.4%) In the case of this Mould Industry study was obtained for the CNC machines studies, with the implementation of Lean Six Sigma tools as obtained a improvement about 20% of global OEE. Research Limitation/implication: This research was revealed that there the moulds are Project unique and difficult to analyze. Moreover, this paper reports that the approach LEAN Six Sigma is very interesting for the continuous improvement of processes and profitability of moulds industry. Originality/Value of paper: This research highlight areas of future research using of quality management methods and Lean Six Sigma tools to analyse and optimize production in the moulds industry. Therefore this research It is considered to promote and adopt high-valued methodologies to support tooling industry in order to achieve global competitive advantages.info:eu-repo/semantics/publishedVersio

Grid structure impact in sparse point representation of derivatives

In the Sparse Point Representation (SPR) method the principle is to retain the function data indicated by significant interpolatory wavelet coefficients, which are defined as interpolation errors by means of an interpolating subdivision scheme. Typically, a SPR grid is coarse in smooth regions, and refined close to irregularities. Furthermore, the computation of partial derivatives of a function from the information of its SPR content is performed in two steps. The first one is a refinement procedure to extend the SPR by the inclusion of new interpolated point values in a security zone. Then, for points in the refined grid, such derivatives are approximated by uniform finite differences, using a step size proportional to each point local scale. If required neighboring stencils are not present in the grid, the corresponding missing point values are approximated from coarser scales using the interpolating subdivision scheme. Using the cubic interpolation subdivision scheme, we demonstrate that such adaptive finite differences can be formulated in terms of a collocation scheme based on the wavelet expansion associated to the SPR. For this purpose, we prove some results concerning the local behavior of such wavelet reconstruction operators, which stand for SPR grids having appropriate structures. This statement implies that the adaptive finite difference scheme and the one using the step size of the finest level produce the same result at SPR grid points. Consequently, in addition to the refinement strategy, our analysis indicates that some care must be taken concerning the grid structure, in order to keep the truncation error under a certain accuracy limit. Illustrating results are presented for 2D Maxwell's equation numerical solutions

The effect of the electric field on lag phase, β-galactosidase production and plasmid stability of a recombinant Saccharomyces cerevisiae strain growing on lactose

Ethanol and β-galactosidase production from cheese whey may significantly contribute to minimise environmental problems while producing value from lowcost raw materials. In this work, the recombinant Saccharomyces cerevisiae NCYC869-A3/pVK1.1 flocculent strain expressing the lacA gene (coding for β-galactosidase) of Aspergillus niger under ADHI promoter and terminator was used. This strain shows high ethanol and β-galactosidase productivities when grown on lactose. Batch cultures were performed using SSlactose medium with 50 gL−1 lactose in a 2-L bioreactor under aerobic and microaerophilic conditions. Temperature was maintained at 30 °C and pH 4.0. In order to determine the effect of an electric field in the fermentation profile, titanium electrodes were placed inside the bioreactor and different electric field values (from 0.5 to 2 Vcm−1) were applied. For all experiments, β-galactosidase activity, biomass, protein, lactose, glucose, galactose and ethanol concentrations were measured. Finally, lag phase duration and specific growth rate were calculated. Significant changes in lag phase duration and biomass yield were found when using 2 Vcm−1. Results show that the electric field enhances the early stages of fermentation kinetics, thus indicating that its application may improve industrial fermentations’ productivity. The increase in electric field intensity led to plasmid instability thus decreasing β-galactosidase production.The authors gratefully acknowledge Fundacao para a Ciencia e a Tecnologia (Portugal) for the scholarships SFRH/BD/11230/2002 and SFRH/BDP/63831/2009 granted to authors I. Castro and C. Oliveira, respectively

Bioaccumulation of amylose-like glycans by Helicobacter pylori

Background: Helicobacter pylori cell surface is composed of lipopolysaccharides (LPSs) yielding structures homologous to mammalian Lewis O-chains blood group antigens. These structures are key mediators in the definition of host-microbial interactions and known to change their expression pattern in response to environmental pressure. Aims:  The present work is focused on the identification of new H. pylori cell-surface glycosides. Special attention is further devoted to provide insights on the impact of in vitro subcultivation on H. pylori cell-surface phenotypes. Methods:  Cell-surface glycans from H. pylori NCTC 11637 and two clinical isolates were recovered from the aqueous phase resulting from phenol:water extraction of intact bacteria. They were evaluated in relation to their sugars and glycosidic-linkages composition by CG-MS, size-exclusion chromatography, NMR, and Mass Spectrometry. H. pylori glycan profile was also monitored during subcultivation in vitro in agar and F12 liquid medium. Results:  All three studied strains produce LPS expressing Lewis epitopes and express bioaccumulate amylose-like glycans. Bioaccumulation of amylose was found to be enhanced with the subcultivation of the bacterium on agar medium and accompanied by a decrease in the expression of LPS O-chains. In contrast, during exponential growth in F12 liquid medium, an opposite behavior is observed, that is, there is an increase in the overall amount of LPS and decrease in amylose content. Conclusions:  This work shows that under specific environmental conditions, H. pylori expresses a phase-variable cell-surface α-(1→4)-glucose moiety

Exercise alters liver mitochondria phospholipidomic profile and mitochondrial activity in non-alcoholic steatohepatitis

Mitochondrial membrane lipid composition is a critical factor in non-alcoholic steatohepatitis (NASH). Exercise is the most prescribed therapeutic strategy against NASH and a potential modulator of lipidmembrane. Thus, we aimed to analyze whether physical exercise exerted preventive (voluntary physical activity - VPA) and therapeutic (endurance training - ET) effect on NASH-induced mitochondrial membrane changes. Sprague-Dawley rats (n = 36) were divided into standard-diet sedentary (SS, n = 12),standard-diet VPA (SVPA, n = 6), high-fat diet sedentary (HS, n = 12) and high-fat diet VPA (HVPA, n = 6). After 9 weeks of diet-specific feeding, half of SS and HS group were engaged in an ET program for 8 weeks/5 day/week/1 h/day (SET, HET). Liver mitochondria were isolated for oxygen consumption and transmembrane-electric potential (Δψ) assays. Mitochondrial phospholipid classes and fatty acids were quantified through thin layer chromatography and gas chromatography, respectively, while cardiolipin(CL), phosphatidylcholine (PC) phosphatidylethanolamine (PE) and phosphatidylinositol (PI) molecular profile was determined by electrospray mass spectrometry. In parallel with histological signs of NASH,high-fat diet decreased PI, CL and PC/PE ratio, whereas PE and phosphatidic acid content increased insedentary animals (HS vs. SS). Moreover, a decrease in linolelaidic, monounsaturated fatty acids content and an increase in saturated fatty acids (SFAS) were observed. Along with phospholipidomic alterations,HS animals showed a decrease in respiratory control ratio (RCR), Δψ and FCCP-induced uncoupling respiration (HS vs. SS). Both phospholipidomic (PC/PE, SFAS) and mitochondrial respiratory alterations were counteracted by exercise interventions. Exercise used as preventive (VPA) or therapeutic (ET) strategies preserved liver mitochondrial phospholipidomic profile and maintained mitochondrial function in a model of NASH

Magnetoliposomes based on manganese ferrite nanoparticles as nanocarriers for antitumor drugs

Publicado em "NanoPT2016 book of abstracts"In this work, manganese ferrite (MnFe2O4) nanoparticles with superparamagnetic behaviour at room temperature and size distribution of 26 ± 5 nm, were obtained by coprecipitation method. Structural and magnetic properties of the nanoparticles (NPs) were evaluated by XRD, HR-TEM and SQUID. The synthesized NPs were either entrapped in liposomes, originating aqueous magnetoliposomes (AMLs), or covered with a lipid bilayer, forming solid magnetoliposomes (SMLs).This work was supported by FEDER through the COMPETE/QREN/EU Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Projects of CFUM [PEst-C/FIS/UI0607/2013 (F-COMP-01-0124-FEDER-022711)] and CQ/UM [PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER -022716)]. FCT, POPH-QREN and FSE are acknowledged for the PhD grant of A.R.O. Rodrigues (SFRH/BD/90949/2012) and for financial support to MAP-Fis PhD Programme

Magnetoliposomes based on manganese ferrite nanoparticles for guided transport of antitumor drugs

Publicado em "RICI6 abstract book"In this work, manganese ferrite nanoparticles with size distribution of 46 ± 17 nm and superparamagnetic behavior were synthesized by coprecipitation method. These magnetic nanoparticles were either entrapped in liposomes, originating aqueous magnetoliposomes (AMLs), or covered with a lipid bilayer, forming solid magnetoliposomes (SMLs).MAP-Fis PhD Programme, FEDER, COMPETE/QREN/EU for financial support to CFUM (PEst-C/FIS/UI0607/2013) and FCT and POPH/QREN for PhD grant (SFRH/BD/90949/2012)