962 resultados para development of processes


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This study investigates the growth and metabolite production of microorganisms causing spoilage of Atlantic cod (Gadus morhua) fillets packaged under air and modified atmosphere (60 % CO2, 40 % O2). Samples were provided by two different retailers (A and B). Storage of packaged fillets occurred at 4 °C and 8 °C. Microbiological quality and metabolite production of cod fillets stored in MAP 4 °C, MAP 8 °C and air were monitored during 13 days, 7 days and 3 days of storage, respectively. Volatile compounds concentration in the headspace were quantified by Selective ion flow tube mass spectrometry and a correlation with microbiological spoilage was studied. The onset of volatile compounds detection was observed to be mostly around 7 log cfu/g of total psychrotrophic count. Trimethylamine and dimethyl sulfide were found to be the dominant volatiles in all of the tested storage conditions, nevertheless there was no close correlation between concentrations of each main VOC and percentages of rejection based on sensory evaluation. According to results it was concluded that they cannot be considered as only indicators of the quality of cod fillets stored in modified atmosphere and air.  

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The effect of pH ranging from 8.0 to 6.8 (total scale - pHT) on fertilization, cleavage and larval development until pluteus stage was assessed in an intertidal temperate sea urchin. Gametes were obtained from adults collected in two contrasting tide pools, one showing a significant nocturnal pH decrease (lowest pHT = 7.4) and another where pH was more stable (lowest pHT = 7.8). The highest pHT at which significant effects on fertilization and cleavage were recorded was 7.6. On the contrary, larval development was only affected below pHT 7.4, a value equal or lower than that reported for several subtidal species. This suggests that sea urchins inhabiting stressful intertidal environments produce offspring that may better resist future ocean acidification. Moreover, at pHT 7.4, the fertilization rate of gametes whose progenitors came from the tide pool with higher pH decrease was significantly higher, indicating a possible acclimatization or adaptation of gametes to pH stress.

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The differentiation of neurons and the outgrowth of neurites depends on microtubule-associated proteins such as tau protein. To study this process, we have used the model of Sf9 cells, which allows efficient transfection with microtubule-associated proteins (via baculovirus vectors) and observation of the resulting neurite-like extensions. We compared the phosphorylation of tau23 (the embryonic form of human tau) with mutants in which critical phosphorylation sites were deleted by mutating Ser or Thr residues into Ala. One can broadly distinguish two types of sites, the KXGS motifs in the repeats (which regulate the affinity of tau to microtubules) and the SP or TP motifs in the domains flanking the repeats (which contain epitopes for antibodies diagnostic of Alzheimer’s disease). Here we report that both types of sites can be phosphorylated by endogenous kinases of Sf9 cells, and that the phosphorylation pattern of the transfected tau is very similar to that of neurons, showing that Sf9 cells can be regarded as an approximate model for the neuronal balance between kinases and phosphatases. We show that mutations in the repeat domain and in the flanking domains have opposite effects. Mutations of KXGS motifs in the repeats (Ser262, 324, and 356) strongly inhibit the outgrowth of cell extensions induced by tau, even though this type of phosphorylation accounts for only a minor fraction of the total phosphate. This argues that the temporary detachment of tau from microtubules (by phosphorylation at KXGS motifs) is a necessary condition for establishing cell polarity at a critical point in space or time. Conversely, the phosphorylation at SP or TP motifs represents the majority of phosphate (>80%); mutations in these motifs cause an increase in cell extensions, indicating that this type of phosphorylation retards the differentiation of the cells.

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Three experiments are reported that examined the process by which trainees learn decision-making skills during a critical incident training program. Formal theories of category learning were used to identify two processes that may be responsible for the acquisition of decision-making skills: rule learning and exemplar learning. Experiments I and 2 used the process dissociation procedure (L. L. Jacoby, 1998) to evaluate the contribution of these processes to performance. The results suggest that trainees used a mixture of rule and exemplar learning. Furthermore, these learning processes were influenced by different aspects of training structure and design. The goal of Experiment 3 was to develop training techniques that enable trainees to use a rule adaptively. Trainees were tested on cases that represented exceptions to the rule. Unexpectedly, the results suggest that providing general instruction regarding the kinds of conditions in which a decision rule does not apply caused them to fixate on the specific conditions mentioned and impaired their ability to identify other conditions in which the rule might not apply. The theoretical, methodological, and practical implications of the results are discussed.

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In 1974 Dr D M Bramwell published his research work at the University of Aston a part of which was the establishment of an elemental work study data base covering drainage construction. The Transport and Road Research Laboratory decided to, extend that work as part of their continuing research programme into the design and construction of buried pipelines by placing a research contract with Bryant Construction. This research may be considered under two broad categories. In the first, site studies were undertaken to validate and extend the data base. The studies showed good agreement with the existing data with the exception of the excavation trench shoring and pipelaying data which was amended to incorporate new construction plant and methods. An inter-active on-line computer system for drainage estimating was developed. This system stores the elemental data, synthesizes the standard time of each drainage operation and is used to determine the required resources and construction method of the total drainage activity. The remainder of the research was into the general topic of construction efficiency. An on-line command driven computer system was produced. This system uses a stochastic simulation technique, based on distributions of site efficiency measurements to evaluate the effects of varying performance levels. The analysis of this performance data quantities the variability inherent in construction and demonstrates how some of this variability can be reconciled by considering the characteristics of a contract. A long term trend of decreasing efficiency with contract duration was also identified. The results obtained from the simulation suite were compared to site records collected from current contracts. This showed that this approach will give comparable answers, but these are greatly affected by the site performance parameters.

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Investment in transport infrastructure can be highly sensitive to uncertainty. The scale and lead time of strategic transport programmes are such that they require continuing policy support and accurate forecasting. Delay, cost escalation and abandonment of projects often result if these conditions are not present. In Part One the physical characteristics of infrastructure are identified as a major constraint on planning processes. The extent to which strategies and techniques acknowledge these constraints is examined. A simple simulation model is developed to evaluate the effects on system development of variations in the scale and lead time of investments. In Part Two, two case studies of strategic infrastructure investment are analysed. The absence of a policy consensus for airport location was an important factor in the delayed resolution of the Third London Airport issue. In London itself, the traffic and environmental effects of major highway investment ultimately resulted in the abandonment of plans to construct urban motorways. In both cases, the infrastructure implications of alternative strategies are reviewed with reference to the problems of uncertainty. In conclusion, the scale of infrastructure investment is considered the most important of the constraints on the processes of transport planning. Adequate appraisal of such constraints may best be achieved by evaluation more closely aligned to policy objectives.

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Az elmúlt néhány évben a külföldi sajtóban és szakmai publikációkban egyre többször jelenik meg a „lean egészségügy”, azaz a karcsú menedzsment alkalmazása az egészségügyben mint téma. Habár az ez irányú kutatások még nemzetközi szinten is csak legfeljebb a hajnalukon tartanak, Magyarországon még szinte teljes a sötétség. Ennek a cikknek az a célja, hogy egyrészről felhívja a kutatók, de még inkább a egészségügyi dolgozók, menedzserek figyelmét erre a menedzsmenteszközre és filozófiára, mely új lehetőségeket kínál, másrészről, hogy áttekintést adjon a területen végzett nemzetközi kutatások eredményeiről. A tanulmány ennek megfelelően alapvetően két részre bontható. Az első felében az egészségügyi szolgáltatások helyzetének rövid jellemzése után a karcsú menedzsment alapjait és az egészségügyi szolgáltatásokban való alkalmazásának eszményét mutatja be. A második fele ugyanakkor 16 esettanulmány elemzésén keresztül bemutatja, hogy meddig jutott a világ a „lean egészségügy” ideájának megvalósításában. _______ In the past few years “Lean Healthcare” – the adaptation of lean management into healthcare settings – turns up as a topic often and often in foreign press and the in the professional publications. Although researches at international level in this field are at best at their dawning, in Hungary the darkness is almost complete. This article aims at one side to draw researchers’ and even more healthcare employees’ and managers’ attention to this management tool and philosophy, which offers new possibilities. From the other side to provide an overview of the results of the researches conducted in this field. Reflecting this doubled aim the study is divided into two major sections. In the first part the situation of the health care providers is shortly described followed by the introduction of the basics of the lean management and the idea of applying it into healthcare services. While the second part of the study shows how far the World reached in realizing the idea of “Lean Healthcare” by analyzing 16 cases.

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As identified by Griffin (1997) and Kahn (2012), manufacturing organisations typically improve their market position by accelerating their product development (PD) cycles. One method for achieving this is to reduce the time taken to design, test and validate new products, so that they can reach the end customer before competition. This paper adds to existing research on PD testing procedures by reporting on an exploratory investigation carried out in a UK-based manufacturing plant. We explore the organisational and managerial factors that contribute to the time spent on testing of new products during development. The investigation consisted of three sections, viz. observations and process modelling, utilisation metrics and a questionnaire-based investigation, from which a proposed framework to improve and reduce the PD time cycle is presented. This research focuses specifically on the improvement of the utilisation of product testing facilities and the links to its main internal stakeholders - PD engineers.

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The purpose of this research is to discover development points for business processes and sales reporting in the recovered paper sourcing organization. The processes under development are both sales and sourcing processes that were determined by the commissioning company. All of these processes have in common that there are used sales orders to organize the money flows correctly. Although the main objective is to source only recovered paper, the sourcing also brings by-products that cannot be utilized and are thus sold. As the purpose of the sales function is to only support the sourcing strategy, it should be organized as efficiently as possible. Investigating the current status of the processes and finding development points help in building proposals for enhanced process descriptions. In order that sales function could be analyzed, should the sales reporting be accurate and present the needed key figures. The current status of the processes as well as the possible problems and development ideas were researched with the help of interviews. Best practices could also be brought from other business lines in the commissioning company. The theory part was build according to relevant literature and scientific articles. The research indicates, that processes have shaped differently in sourcing organization’s business units. Local infrastructure and legislation sets certain limitations to the sourcing of recovered paper, and these circumstances cannot be changed. Customer-supplier power relations also affect to the formulation of business processes. In order to steer the processes, there has to be more internal controls. Still, the enterprise resource planning system also sets boundaries how the processes can be made more efficient.

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Hevea brasiliensis is a native species of the Amazon Basin of South America and the primary source of natural rubber worldwide. Due to the occurrence of South American Leaf Blight disease in this area, rubber plantations have been extended to suboptimal regions. Rubber tree breeding is time-consuming and expensive, but molecular markers can serve as a tool for early evaluation, thus reducing time and costs. In this work, we constructed six different cDNA libraries with the aim of developing gene-targeted molecular markers for the rubber tree. A total of 8,263 reads were assembled, generating 5,025 unigenes that were analyzed; 912 expressed sequence tags (ESTs) represented new transcripts, and two sequences were highly up-regulated by cold stress. These unigenes were scanned for microsatellite (SSR) regions and single nucleotide polymorphisms (SNPs). In total, 169 novel EST-SSR markers were developed; 138 loci were polymorphic in the rubber tree, and 98 % presented transferability to six other Hevea species. Locus duplication was observed in H. brasiliensis and other species. Additionally, 43 SNP markers in 13 sequences that showed similarity to proteins involved in stress response, latex biosynthesis and developmental processes were characterized. cDNA libraries are a rich source of SSR and SNP markers and enable the identification of new transcripts. The new markers developed here will be a valuable resource for linkage mapping, QTL identification and other studies in the rubber tree and can also be used to evaluate the genetic variability of other Hevea species, which are valuable assets in rubber tree breeding.

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Purpose - The purpose of this paper is to identify the key elements of a new rapid prototyping process, which involves layer-by-layer deposition of liquid-state material and at the same time using an ultraviolet line source to cure the deposited material. This paper reports studies about the behaviour of filaments, deposition accuracy, filaments interaction and functional feasibility of system. Additionally, the author describes the process which has been proposed, the equipment that has been used for these studies and the material which was developed in this application. Design/methodology/approach - The research has been separated into three study areas in accordance with their goals. In the first, both the behaviour of filament and deposition accuracy was studied. The design of the experiment is described with focus on four response factors (bead width, filament quality, deposition accuracy and deposition continuity) along with function of three control factors (deposition height, deposition velocity and extrusion velocity). The author also studied the interaction between filaments as a function of bead centre distance. In addition, two test samples were prepared to serve as a proof of the methodology and to verify the functional feasibility of the process which has been studied. Findings - The results show that the proposed process is functionally feasible, and that it is possible to identify the main effects of control factors over response factors. That analysis is used to predict the condition of process as a function of the parameters which control the process. Also identified were distances of centre beads which result in a specific behaviour. The types of interaction between filaments were analysed and sorted into: union, separation and indeterminate. At the end, the functional feasibility of process was proved whereby two test parts could be built. Originality/value - This paper proposes a new rapid prototyping process and also presents test studies related to this proposition. The author has focused on the filament behaviour, deposition accuracy, interaction between filaments and studied the functional feasibility of process to provide new information about this process, which at the same time is useful to the development of other rapid prototyping processes.

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