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An ontology for the structured storage, retrieval, and analysis of data on lithium-ion battery materials and electrode-to-cell production is presented. It provides a logical structure that is mapped onto a digital architecture and used to visualize, correlate, and make predictions in battery production, research, and development. Materials and processes are specified using a predetermined terminology; a chain of unit processes (steps) connects raw materials and products (items) of battery cell production. The ontology enables the attachment of analytical methods (characterization methods) to items. Workshops and interviews with experts in battery materials and production processes are conducted to ensure that the structure is conformable both for industrial-scale and laboratory-scale data generation and implementation. Raw materials and intermediate products are identified and defined for all steps to the final battery cell. Steps and items are defined based on current standard materials and process chains using terms that are in common use. Alternative structures and the connection of the ontology to other existing ontologies are discussed. The contribution provides a pragmatic, accessible way to unify the storage of materials-oriented lithium-ion battery production data. It aids the linkage of such data with domain knowledge and the automation of data analysis in production and research.

Vodstvo podjetja se je zaradi velikega porasta naročil odločilo za postopno razširitev proizvodnih kapacitet. V prvi fazi se bo zgradil nov objekt, ki je lokacijsko umeščen na mesto, kjer je bilo do sedaj medfazno skladišče, to pa se bo premestilo na skrajni konec podjetja. V ta namen smo v okviru magistrskega dela popisali obstoječe stanje s pomočjo simulacijskega modela in ga primerjali s stanjem po premestitvi. Ugotovili smo, da premestitev podaljša transportno pot in ne vpliva na produktivnost proizvodnje. Model obstoječe proizvodnje smo preoblikovali iz delavniške v celično razmestitev in na osnovi simulacijskih rezultatov izračunali ekonomsko upravičenost. Due to the large increase in orders, the company's management decided to gradually expand production capacity. In the first phase, a new facility will be built, which is located in the place where the interphase warehouse was until now, and it will be moved to the far end of the company. For this purpose, as part of the master's thesis, we described the existing situation with the help of a simulation model and compared it with the situation after relocation. We found out that the relocation lengthens of the transportation route does not affect the production productivity. We converted the existing production model from a workshop to a cell deployment and calculated the economic justification based on the simulation results.

Li-ion cells of the industrially-relevant 21700 format were built on pilot-scale with tabs made from (a) the electrodes’ current collecting foils (Al and Cu, “foil tabs”) in comparison with (b) conventional tabs (Al and Ni) welded to the electrodes’ current collecting foils (“welded tabs”). Both cell types use the same anode (graphite), cathode (NMC622), separator, electrolyte, as well as the same tab positions. This allows a direct comparison of welded tabs and foil tabs regarding formation, C-rate capability, cell electrical resistance, and long-term cycling stability tests. Our data reproducibly shows 14.4% longer cycling stability and 11.2% increased total charge throughput in the case of the cells with foil tabs until 80% SOH, which is likely due to less inhomogeneities in the case of the foil tab design.

Background Many data are available on expansion protocols for mesenchymal stromal cells (MSCs) for both experimental settings and manufacturing for clinical trials. However, there is a lack of information on translation of established protocols for Good Manufacturing Practice (GMP) from validation to manufacturing for clinical application. We present the validation and translation of a standardized pre-clinical protocol for isolation and expansion of MSCs for a clinical trial for reconstitution of alveolar bone. Methods Key parameters of 22 large-scale expansions of MSCs from bone marrow (BM) for validation were compared with 11 expansions manufactured for the clinical trial “Jaw bone reconstruction using a combination of autologous mesenchymal stromal cells and biomaterial prior to dental implant placement (MAXILLO1)” aimed at reconstruction of alveolar bone. Results Despite variations of the starting material, the robust protocol led to stable performance characteristics of expanded MSCs. Manufacturing of the autologous advanced therapy medicinal product MAXILLO-1-MSC was possible, requiring 21 days for each product. Transport of BM aspirates and MSCs within 24 h was guaranteed. MSCs fulfilled quality criteria requested by the national competent authority. In one case, the delivered MSCs developed a mosaic in chromosomal finding, showing no abnormality in differentiation capacity, growth behavior or surface marker expression during long-term culture. The proportion of cells with the mosaic decreased in long-term culture and cells stopped growth after 38.4 population doublings. Conclusions Clinical use of freshly prepared MSCs, manufactured according to a standardized and validated protocol, is feasible for bone regeneration, even if there was a long local distance between manufacturing center and clinical site. Several parameters, such as colony forming units fibroblasts (CFU-F), percentage of CD34+ cells, cell count of mononuclear cells (MNCs) and white blood cells (WBCs), of the BM may serve as a predictive tool for the yield of MSCs and may help to avoid unnecessary costs for MSC manufacturing due to insufficient cell expansion rates.

Processes : open access journal 9(4), 575 (2021). doi:10.3390/pr9040575 special issue: "Special Issue "Cell, Gene and Regenerative Therapy Processes" / Special Issue Editors: Dr. Qasim Rafiq, Guest Editor; Dr. Ioannis Papantoniou, Guest Editor; Ms. Jelena Ochs, Guest Editor", Published by MDPI, Basel

Frontiers in Bioengineering and Biotechnology 8, 580352 (2020). doi:10.3389/fbioe.2020.580352, Published by Frontiers Media, Lausanne

Human cardiomyocytes (CMs) have potential for use in therapeutic cell therapy and high-throughput drug screening. Because of the inability to expand adult CMs, their large-scale production from human pluripotent stem cells (hPSC) has been suggested. Significant improvements have been made in understanding directed differentiation processes of CMs from hPSCs and their suspension culture-based production at chemically defined conditions. However, optimization experiments are costly, time-consuming, and highly variable, leading to challenges in developing reliable and consistent protocols for the generation of large CM numbers at high purity. This study examined the ability of data-driven modeling with machine learning for identifying key experimental conditions and predicting final CM content using data collected during hPSC-cardiac differentiation in advanced stirred tank bioreactors (STBRs). Through feature selection, we identified process conditions, features, and patterns that are the most influential on and predictive of the CM content at the process endpoint, on differentiation day 10 (dd10). Process-related features were extracted from experimental data collected from 58 differentiation experiments by feature engineering. These features included data continuously collected online by the bioreactor system, such as dissolved oxygen concentration and pH patterns, as well as offline determined data, including the cell density, cell aggregate size, and nutrient concentrations. The selected features were used as inputs to construct models to classify the resulting CM content as being “sufficient” or “insufficient” regarding pre-defined thresholds. The models built using random forests and Gaussian process modeling predicted insufficient CM content for a differentiation process with 90% accuracy and precision on dd7 of the protocol and with 85% accuracy and 82% precision at a substantially earlier stage: dd5. These models provide insight into potential key factors affecting hPSC cardiac differentiation to aid in selecting future experimental conditions and can predict the final CM content at earlier process timepoints, providing cost and time savings. This study suggests that data-driven models and machine learning techniques can be employed using existing data for understanding and improving production of a specific cell type, which is potentially applicable to other lineages and critical for realization of their therapeutic applications.

Reactive oxygen species (ROS) can act as signaling molecules involved in the acclimation of plants to various abiotic and biotic stresses. However, it is not clear how the generalized increases in ROS and downstream signaling events that occur in response to stressful conditions are coordinated to modify plant growth and development. Previous studies of maize (Zea mays L.) primary root growth under water deficit stress showed that cell elongation is maintained in the apical region of the growth zone but progressively inhibited further from the apex, and that the rate of cell production is also decreased. It was observed that apoplastic ROS, particularly hydrogen peroxide (H2O2), increased specifically in the apical region of the growth zone under water stress, resulting at least partly from increased oxalate oxidase activity in this region. To assess the function of the increase in apoplastic H2O2 in root growth regulation, transgenic maize lines constitutively expressing a wheat oxalate oxidase were utilized in combination with kinematic growth analysis to examine effects of increased apoplastic H2O2 on the spatial pattern of cell elongation and on cell production in well-watered and water-stressed roots. Effects of H2O2 removal (via scavenger pretreatment) specifically from the apical region of the growth zone were also assessed. The results show that apoplastic H2O2 positively modulates cell production and root elongation under well-watered conditions, whereas the normal increase in apoplastic H2O2 in water-stressed roots is causally related to down-regulation of cell production and root growth inhibition. The effects on cell production were accompanied by changes in spatial profiles of cell elongation and in the length of the growth zone. However, effects on overall cell elongation, as reflected in final cell lengths, were minor. These results reveal a fundamental role of apoplastic H2O2 in regulating cell production and root elongation in both well-watered and water-stressed conditions.

More than 60% of tree phytomass is concentrated in stem wood, which is the result of periodic activity of the cambium. Nevertheless, there are few attempts to quantitatively describe cambium dynamics. In this study, we develop a state-of-the-art band model of cambium development, based on the kinetic heterogeneity of the cambial zone and the connectivity of the cell structure. The model describes seasonal cambium development based on an exponential function under climate forcing which can be effectively used to estimate the seasonal cell production for individual trees. It was shown that the model is able to simulate different cell production for fast-, middle- and slow-growing trees under the same climate forcing. Based on actual measurements of cell production for two contrasted trees, the model effectively reconstructed long-term cell production variability (up to 75% of explained variance) of both tree-ring characteristics over the period 1937−2012. The new model significantly simplifies the assessment of seasonal cell production for individual trees of a studied forest stand and allows the entire range of individual absolute variability in the ring formation of any tree in the stand to be quantified, which can lead to a better understanding of the anatomy of xylem formation, a key component of the carbon cycle.

BackgroundThe major fleshy tissues of the apple fruit are spatially separable into cortex and pith. These tissues display differential growth during development. Key features of such differential growth, and sink metabolic programs supporting it have not been investigated previously. We hypothesized that differential growth between these fruit tissues is supported by differential sink metabolic programs, particularly during early development. Growth, metabolite concentrations, and transcript abundance of metabolism-related genes were measured to determine characteristics of differential growth and their underlying metabolic programs.ResultsThe cortex displayed > 5-fold higher growth than the pith during early fruit development, indicating that differential growth was established during this period. Further, when resource availability was increased through sink-removal, cortex growth was preferentially enhanced. Greatest diversity in metabolic programs between these tissues was evident during early fruit development. Higher cortex growth during early development was facilitated by increased catabolism of imported carbon (C) resources, sorbitol and sucrose, and the nitrogen (N) resource, asparagine. It was also associated with enhanced primary C metabolism, and C storage as malate and quinate. The pith metabolic program during this period involved limited allocation of C and N to growth, but greater allocation to storage, and enhanced sucrose-sucrose cycling.ConclusionsTogether, these data indicate that the fruit cortex tissue displays a resource intensive metabolic program during early fruit development. This provides the C backbones, proteins, energy and osmolytes to support its higher growth.

BACKGROUND AIMS: Autologous macrophage therapy represents a potentially significant therapeutic advance for the treatment of severe progressive liver cirrhosis. Administration of macrophages has been shown to reduce inflammation and drive fibrotic scar breakdown and tissue repair in relevant models. This therapeutic approach is being assessed for safety and feasibility in a first-in-human trial (MAcrophages Therapy for liver CirrHosis [MATCH] trial).METHODS: We outline the development and validation phases of GMP production. This includes use of the CliniMACS Prodigy cell sorting system to isolate CD14(+) cells; optimizing macrophage culture conditions, assessing cellular identity, product purity, functional capability and determining the stability of the final cell product.RESULTS: The GMP-compliant macrophage products have a high level of purity and viability, and have a consistent phenotypic profile, expressing high levels of mature macrophage markers 25F9 and CD206 and low levels of CCR2. The macrophages demonstrate effective phagocytic capacity, are constitutively oriented to an anti-inflammatory profile and remain responsive to cytokine and TLR stimulation. The process validation shows that the cell product in excipient is remarkably robust, consistently passing the viability and phenotypic release criteria up to 48 hours after harvest.CONCLUSIONS: This is the first report of validation of a large-scale, fully Good Manufacturing Practice-compliant, autologous macrophage cell therapy product for the potential treatment of cirrhosis. Phenotypic and functional assays confirm that these cells remain functionally viable for up to 48 h, allowing significant flexibility in administration to patients.

Purpose: In this paper, we have proposed a new model for designing a Cellular Manufacturing System (CMS) for minimizing the costs regarding a limited number of cells to be formed by assigning workforce. Design/methodology/approach: Pursuing mathematical approach and because the problem is NP-Hard, two meta-heuristic methods of Simulated Annealing (SA) and Particle Swarm Optimization (PSO) algorithms have been used. A small randomly generated test problem with real-world dimensions has been solved using simulated annealing and particle swarm algorithms. Findings: The quality of the two algorithms has been compared. The results showed that PSO algorithm provides more satisfactory solutions than SA algorithm in designing a CMS under uncertainty demands regarding the workforce allocation. Originality/value: In the most of the previous research, cell production has been considered under certainty production or demand conditions, while in practice production and demand are in a dynamic situations and in the real settings, cell production problems require variables and active constraints for each different time periods to achieve better design, so modeling such a problem in dynamic structure leads to more complexity while getting more applicability. The contribution of this paper is providing a new model by considering dynamic production times and uncertainty demands in designing cells.

The adoptive transfer of chimeric antigen receptor (CAR)-modified T cells is attracting growing interest for the treatment of malignant diseases. Early trials with anti-CD19 CAR T cells have achieved spectacular remissions in B-cell leukemia and lymphoma, so far refractory, very recently resulting in the Food and Drug Administration approval of CD19 CAR T cells for therapy. With further applications and increasing numbers of patients, the reproducible manufacture of high-quality clinical-grade CAR T cells is becoming an ever greater challenge. New processing techniques, quality-control mechanisms, and logistic developments are required to meet both medical needs and regulatory restrictions. This paper summarizes the state-of-the-art in manufacturing CAR T cells and the current challenges that need to be overcome to implement this type of cell therapy in the treatment of a variety of malignant diseases and in a greater number of patients.

Dissertação de mestrado integrado em Engenharia e Gestão Industrial, O presente projeto de dissertação é resultado de um projeto em ambiente empresarial desenvolvido no âmbito do 5º ano do curso de Mestrado Integrado em Engenharia e Gestão Industrial da Universidade do Minho. Através da aplicação de algumas ferramentas Lean, esta dissertação tem como objetivo principal a reconfiguração de células de costura, mais concretamente, o aumento da produtividade e do ganho de área, a simplificação dos fluxos de peça e a redução do número de recursos, e teve lugar na unidade de Arcos de Valdevez da Coindu S.A., uma empresa inserida na indústria automóvel que se dedica à produção de capas de assento. A metodologia de investigação que serviu de base para esta dissertação foi a metodologia Action Research uma vez que é uma estratégia caracterizada pela componente participativa do investigador. O projeto partiu assim de uma descrição e análise crítica da situação atual na qual foram identificados os principais problemas no sector de costura dos produtos da marca Porsche, como foi o caso dos baixos indicadores de desempenho, balanceamentos desajustados, elevadas distâncias percorridas na costura das capas, desorganização de alguns postos, elevados tempos de setup, bem como a falta de envolvimento dos colaboradores. Consequentemente, foram elaboradas algumas propostas de melhoria para combater os problemas identificados. Estas baseavam-se essencialmente na criação de células de costura com mais pessoas do que as atuais com o objetivo de aumentar a taxa de produção e o output por pessoa. Para isso, foram elaborados novos balanceamentos e layouts para cada peça que compõe o carro Porsche, foram criadas estruturas para a redução do tempo de setup e organização dos postos críticos, entre outras propostas. A reconfiguração das células permitiu assim que a empresa obtivesse vários ganhos: aumento da produtividade e taxa de produção gerais na costura Porsche de 22% e 56%, respetivamente, redução do tempo de ciclo das peças em 27%, diminuição das distâncias percorridas em 36% e uma redução média no tempo de setup de 42%, o que, em conjunto, possibilitaram uma redução dos recursos humanos necessários em 42%, entre outros., The present project is the result of a project developed in an industrial environment, developed as part of the Integrated Master in Engineering and Industrial Management of the University of Minho. By applying some of the Lean tools, this dissertation aims the reconfiguration of sewing cells, more specifically, to increase productivity and area gain, to simplify the piece flows and to reduce the number of resources, and it was held at Arcos de Valdevez unity of Coindu S.A., a company inserted in the automotive industry that produces seat covers. This project was made based on the Action-Research methodology since it's a known strategy due to the participative role taken by the researcher and it is the most used methodology in an industrial context. The project begun with a description and critic analysis of the current situation, in which some problems were pointed out regarding the sewing part of the Porsche's products production, those being the low values of some key performance indicators, the uneven cell balancing, the long distances traveled by the covers throughout the sewing operations, disorganization of some of the workstations, high setup times, as wells as the lack of involvement of the workers. Because of that, some improvement proposals were elaborated in order to tackle the identified problems. The improvement proposals found were based on the creation of bigger sewing cells so the production rate would increase and, hopefully, the output per person would to. To do that, new team balancing and layouts were made for each piece of a Porsche car, as wells as new structures to reduce the setup time and organize the critic workstations, among other proposals. The reconfiguration of cells allowed the company to achieve some gains: boost in productivity and production rate in 22% and 56%, respectively, a decrease of cycle time of all Porsche pieces in 27%, a decrease in the traveled distances in 36% and a decrease in setup time of 42%, that, in a general way, allowed the reduction of the needed human resources in 42%, among others.

Sandy surface sediments of tidal flats exhibit high microbial activity due to the fast and deep-reaching transport of oxygen and nutrients by porewater advection. On the other hand during low tide, limited transport results in nutrient and oxygen depletion concomitant to the accumulation of microbial metabolites. This study represents the first attempt to use flow-through reactors to investigate virus production, virus transport and the impact of tides and season in permeable sediments. The reactors were filled with intertidal sands of two sites (North beach site and backbarrier sand flat of Spiekeroog island in the German Wadden Sea) to best simulate advective porewater transport through the sediments. Virus and cell release along with oxygen consumption were measured in the effluents of reactors during continuous flow of water through the sediments as well as in tidal simulation experiments where alternating cycles with and without water flow (each for 6 h) were operated. The results showed net rates of virus production (0.3–13.2 × 106 viruses cm−3 h−1) and prokaryotic cell production (0.3–10.0 × 105 cells cm−3 h−1) as well as oxygen consumption rates (56–737 μmol l−1 h−1) to be linearly correlated reflecting differences in activity, season and location of the sediments. Calculations show that total virus turnover was fast with 2 to 4 days, whereas virus-mediated cell turnover was calculated to range between 5–13 or 33–91 days depending on the assumed burst sizes (number of viruses released upon cell lysis) of 14 or 100 viruses, respectively. During the experiments, the homogenized sediments in the reactors became vertically structured with decreasing microbial activities and increasing impact of viruses on prokaryotic mortality with depth. Tidal simulation clearly showed a strong accumulation of viruses and cells in the top sections of the reactors when the flow was halted indicating a consistently high virus production during low tide. In conclusion, cell lysis products due to virus production may fuel microbial communities in the absence of advection-driven nutrient input, but are eventually washed off the surface sediment during high tide and being transported into deeper sediment layers or into the water column together with the produced viruses.

The purpose of the present study was to characterize the progression of red blood cell volume (RBCV) expansion and potential volumetric and endocrine regulators of erythropoiesis during endurance training (ET). Nine healthy, untrained volunteers (age = 27 +/- 4 yr) underwent supervised ET consisting of 3-4 x 60 min cycle ergometry sessions per week for 8 wk. Plasma volume (PV), RBCV, and overnight fasting hematological markers were determined before and at weeks 2, 4, and 8 of ET. In addition, plasma erythropoietin (EPO), cortisol, copeptin, and proatrial natriuretic peptide concentrations were measured during a 3-h morning period at baseline and postexercise at weeks 1 and 8. PV increased from baseline (2,405 +/- 335 ml) at weeks 2, 4, and 8 (+/- 374 +/- 194, +505 +/- 156, and + 341 +/- 160 ml, respectively, P

Although habitually considered as a whole, xylogenesis is a complex process of division and maturation of a pool of cells where the relationship between the phenological phases generating such a growth pattern remains essentially unknown. This study investigated the causal relationships in cambium phenology of black spruce [Picea mariana (Mill.) BSP] monitored for 8 years on four sites of the boreal forest of Quebec, Canada. The dependency links connecting the timing of xylem cell differentiation and cell production were defined and the resulting causal model was analysed with d-sep tests and generalized mixed models with repeated measurements, and tested with Fisher’s C statistics to determine whether and how causality propagates through the measured variables. The higher correlations were observed between the dates of emergence of the first developing cells and between the ending of the differentiation phases, while the number of cells was significantly correlated with all phenological phases. The model with eight dependency links was statistically valid for explaining the causes and correlations between the dynamics of cambium phenology. Causal modelling suggested that the phenological phases involved in xylogenesis are closely interconnected by complex relationships of cause and effect, with the onset of cell differentiation being the main factor directly or indirectly triggering all successive phases of xylem maturation.

The interaction between xylem phenology and climate assesses forest growth and productivity and carbon storage across biomes under changing environmental conditions. We tested the hypothesis that patterns of wood formation are maintained unaltered despite the temperature changes across cold ecosystems. Wood microcores were collected weekly or biweekly throughout the growing season for periods varying between 1 and 13 years during 1998–2014 and cut in transverse sections for assessing the onset and ending of the phases of xylem differentiation. The data set represented 1321 trees belonging to 10 conifer species from 39 sites in the Northern Hemisphere and covering an interval of mean annual temperature exceeding 14 K. The phenological events and mean annual temperature of the sites were related linearly, with spring and autumnal events being separated by constant intervals across the range of temperature analysed. At increasing temperature, first enlarging, wall-thickening and mature tracheids appeared earlier, and last enlarging and wall-thickening tracheids occurred later. Overall, the period of wood formation length- ened linearly with the mean annual temperature, from 83.7 days at -2 °C to 178.1 days at 12 °C, at a rate of 6.5 days °C-1. April–May temperatures produced the best models predicting the dates of wood formation. Our findings demonstrated the uniformity of the process of wood formation and the importance of the environmental conditions occurring at the time of growth resumption. Under warming scenarios, the period of wood formation might lengthen synchronously in the cold biomes of the Northern Hemisphere.

Dissertação de mestrado em Engenharia Industrial, A presente dissertação foi realizada no âmbito do Mestrado em Engenharia Industrial (ramo Gestão Industrial) e foi desenvolvida na empresa Bosch Car Multimédia Portugal, S.A. O principal objetivo desta dissertação foi analisar e melhorar o desempenho de uma célula de produção de painéis digitais de instrumentos, através da avaliação e redução dos seus principais desperdícios e da aplicação de princípios e ferramentas Lean Manufacturing. De forma a analisar e a diagnosticar a área produtiva em estudo, utilizou-se a ferramenta amostragem do trabalho (multimomento) onde se identificaram os principais desperdícios, nomeadamente manuseamento excessivo de materiais, transportes e movimentações, reparação e esperas. Deste modo, realizaram-se várias análises de processo de forma a identificar as causas de tais desperdícios. Após a identificação dos problemas apresentaram-se propostas de melhoria, nomeadamente alteração do tipo de embalagem de dois materiais críticos, alteração de layout da célula, algumas otimizações de processo e implementação de oficina para programação do PCB NVÍDIA. As propostas de melhoria apresentadas foram todas implementadas. Os resultados mais relevantes foram no output das 5 células do mesmo cliente. Estas otimizações levaram a um ganho anual de 45 800 peças e € 90 000 com a redução do tempo-pessoa (VT). Para além destes ganhos, conseguiu-se reduzir o work in process em 17%, reduzir o tempo de atravessamento em 21,1% e aumentar o rácio de valor acrescentado no posto bottleneck em 20,7%., The present work was performed under the Master in Industrial Engineering (branch Industrial Management) and developed at Bosch Car Multimedia Portugal, S.A. The main goal of this dissertation was to analyze and improve the performance of a digital instruments panel production cell, through the evaluation and reduction of the main waste and through the application of Lean Manufacturing principles and tools. In order to analyze and diagnose the intended productive area, we use a working sample tool (multimomento) which identifies the main wastes, as excessive material handling, transport and crossing time, repairs and waits. In this way, several process analyzes were performed in order to identify the causes of such wastes. After the problems identification some improvement measures were presented, namely the change of two critical components package type, cell layout change, some process optimization and the implementation of a pool cell for NVIDIA PCB programming. All the improvement proposals submitted were implemented. The most relevant results were on the 5 cells output from the same customer. These enhancements lead to an annual gain of 45 800 units and € 90 000 due to VT reduction. In addition to these gains, it was possible also reduce the work in process in 17%, the throughput time in 21,1% and increase the added value ratio on our bottleneck station in 20,7%.

Purpose: This research, by using the SIMIO simulation platform, provides a quantitative and comparative analysis of how the efficiency of four different cell production modes is affected. It is hoped that the results will be of some help for garment factories to optimize their production lines. Design/methodology/approach: The SIMIO simulation platform was employed in the research and comparisons were made of the simulation test results about the four popular cellular manufacturing modes. Findings: The operation mode, number of operators, and number of buffer areas are key factors affecting the production line efficiency, and need to be reasonably set to achieve the highest efficiency. Originality/value: As most research literature so far is qualitative, this research provided a simulation-based quantitative analysis of the production efficiency under different cell production modes.

Neighboring trees growing under identical environmental conditions can exhibit different dynamics and periods of growth. Despite the recent advances in cambial biology, the exogenous and endogenous factors generating asynchronous xylem growths still remain undetermined. This study investigated timings and duration of xylem formation in maritime pine (Pinus pinaster Ait.) from an even-aged plantation in Portugal growing under Mediterranean climate. Cambial phenology and stem diameter were monitored weekly, from March to December 2010, on two classes of trees divided according to the tree ring widths of the last 15 years, but similar age and size: fast- and slow-growing trees. We tested the hypothesis that differences in tree ring widths result from cell production which in turn affects timings of xylogenesis and that the bimodal growth pattern, typical of the Mediterranean, originates from a double reactivation of the cambium: in spring and autumn. Cambial activity started earlier and ended later in fast-growing trees, confirming that cell production is a key factor determining the duration of xylogenesis. Intra-annual variations in stem diameter recorded by band dendrometers revealed two peaks of increment occurring in spring and late summer. However, the number of cambial cells did not increase in late summer, which suggested that the second peak of increment was caused by stem rehydration, rather than by a reactivation of cell division. These results demonstrated that the variability in the timings of xylem phenology observed among trees of the same age and size and growing under similar environmental conditions was closely related to cell production and not to age or size per se. This study was supported by the Fundac¸a˜o para a Cieˆncia e a Tecnologia, Ministe´rio da Educac¸a˜o e Cieˆncia (FCT) cofinanced by Compete, through the project PTDC/AAC-AMB/111675/ 2009. Joana Vieira was supported by a Ph.D. Grant (SFRH/BD/ 48089/2008) and Filipe Campelo by a postdoctoral research grant (SFRH/BPD/47822/2008), both grants from FCT with funds from POPH (Portuguese Operational Human Potential Program) and QREN Portugal (Portuguese National Strategic Reference Framework).

Background and Aims Ongoing global warming has been implicated in shifting phenological patterns such as the timing and duration of the growing season across a wide variety of ecosystems. Linear models are routinely used to extrapolate these observed shifts in phenology into the future and to estimate changes in associated ecosystem properties such as net primary productivity. Yet, in nature, linear relationships may be special cases. Biological processes frequently follow more complex, non-linear patterns according to limiting factors that generate shifts and discontinuities, or contain thresholds beyond which responses change abruptly. This study investigates to what extent cambium phenology is associated with xylem growth and differentiation across conifer species of the northern hemisphere. Methods Xylem cell production is compared with the periods of cambial activity and cell differentiation assessed on a weekly time scale on histological sections of cambium and wood tissue collected from the stems of nine species in Canada and Europe over 1–9 years per site from 1998 to 2011. Key Results The dynamics of xylogenesis were surprisingly homogeneous among conifer species, although dispersions from the average were obviously observed. Within the range analysed, the relationships between the phenological timings were linear, with several slopes showing values close to or not statistically different from 1. The relationships between the phenological timings and cell production were distinctly non-linear, and involved an exponential pattern. Conclusions The trees adjust their phenological timings according to linear patterns. Thus, shifts of one phenological phase are associated with synchronous and comparable shifts of the successive phases. However, small increases in the duration of xylogenesis could correspond to a substantial increase in cell production. The findings suggest that the length of the growing season and the resulting amount of growth could respond differently to changes in environmental conditions.

Dissertação de mestrado em Engenharia Industrial – Gestão Industrial, A presente dissertação de mestrado foi desenvolvida na empresa Delphi Automotive Systems - Portugal S.A., em Braga, no seguimento da constatação por parte da empresa da existência de excesso de movimentações, transportes e WIP provocados essencialmente pela organização fortemente orientada ao processo desta área. Os principais objetivos desta dissertação são a análise e diagnóstico da unidade produtiva de montagem de antenas, a identificação e avaliação dos seus principais desperdícios e a criação de propostas de melhoria de forma a reduzir os desperdícios e aumentar o seu desempenho. Por forma a analisar e a diagnosticar a unidade produtiva utilizou-se a ferramenta waste identification diagram (WID) onde se identificaram os desperdícios, nomeadamente elevados transportes, movimentações, esperas e trabalho em curso (WIP). No sentido de identificar as razões que levam a tais desperdícios recorreu-se ao diagrama de causa-efeito (diagrama de Ishikawa). Identificadas as causas, fez-se propostas de melhoria de forma a colmatar estes desperdícios encontrados, destacando-se a proposta de melhoria que passa pela criação de células de produção para a família de antenas que representa elevados custos com desperdícios para a empresa – as antenas Ford ECBP. Com esta proposta pretende-se reduzir 23995,04€/ano em WIP, as distâncias percorridas pelos operadores em 104 291,56 €/ano, o tempo de atravessamento de 765,67 minutos para 8,352 minutos, o espaço ocupado em 14%, aumentar a capacidade produtiva em 5728 antenas/dia e aumentar o rácio de valor acrescentado de 0,028% para 2,57%., This dissertation was developed in Delphi Automotive Systems Company-Portugal S.A., in Braga, following verification by the company of the existence of excess movement, transport and WIP caused essentially by the organization strongly oriented to the process in this area. The main objectives of this dissertation are the analysis and diagnosis of the production unit antennas assembly, the identification and assessment of their main waste and creating proposals for improvements in order to reduce waste and increase your performance. In order to analyse and diagnose the productive unit used the waste identification diagram (WID) which identified the waste, including high transport, movimentation, waits and work in progress (WIP). In order to identify the reasons that lead to such wastes resorted to the cause-effect diagram (Ishikawa diagram). Identified the causes, it was proposed improvements in order to bridge these waste found, highlighting the improved proposal that goes through the creation of production cells for the family of antennas that represents high costs with waste to the company – the Ford ECBP antennas. This proposal is intended to reduce 23995,04€ per year in WIP, the distances covered by the operators in 104291.56 € per year, crossing time of 765,67 minutes to 8,352 minutes, the space occupied on 14%, to increase the production capacity in 5728 antennas per day and increase the ratio of added value of 0,028% to 2,57%.

The Cellular production consists on containing the components and machines in cells, combining the production for process with the online productión, to obtain the advantages that offer both processes, in this case the company can offer variety of products and low costs., La producción celular, consiste en agrupar los componentes y máquinas en células, combinando la producción por proceso con la producción en línea, para obtener las ventajas que ofrecen ambos métodos, como son la variedad de productos y los bajos costos.

Xylogenesis was monitored during 2003 and 2004 in a timberline environment in southern Italy to assess links between temperature, cambial phenology and wood formation on a short-time scale. Wood microcores were collected weekly from May to October from 10 trees of Pinus leucodermis Ant., histological sections were cut with a rotary microtome and anatomical features of the developing and mature tracheids were observed and measured along the growing tree ring. Spring 2003 was hotter than spring 2004, with temperatures up to 2.6 degrees C above historical means. The hotter conditions resulted in an earlier onset of cambial activity and all differentiation phases of about 20 days, resulting in an increased duration of xylogenesis of about 23 days. Air and stem temperatures at which xylogenesis had a 0.5 probability of being active were calculated with logistic regressions fitted on binary responses. In both years, similar thresholds were estimated with daily mean values of 8.2 and 9.5 degrees C for air and stem temperatures, respectively. The observed convergent responses of cambium phenology to temperature during the two contrasting springs confirm the key role of this environmental factor in determining the onset and duration of wood formation in timberline areas. The intra-annual dynamics of ring-width increase differed between years, with significantly narrower rings formed in 2004 than in 2003. These differences were mainly related to cell size because larger earlywood tracheids were produced in 2003. This study demonstrates the plasticity of tree-ring formation in response to high temperatures as a result of modifications in the onset and duration of differentiation.