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Production Facilities (production + facility)
Selected AbstractsA procedure for setting up high-throughput nanolitre crystallization experiments.ACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2005Crystallization workflow for initial screening, automated storage, imaging, optimization Crystallization trials at the Division of Structural Biology in Oxford are now almost exclusively carried out using a high-throughput workflow implemented in the Oxford Protein Production Facility. Initial crystallization screening is based on nanolitre-scale sitting-drop vapour-diffusion experiments (typically 100,nl of protein plus 100,nl of reservoir solution per droplet) which use standard crystallization screening kits and 96-well crystallization plates. For 294,K crystallization trials the barcoded crystallization plates are entered into an automated storage system with a fully integrated imaging system. These plates are imaged in accordance with a pre-programmed schedule and the resulting digital data for each droplet are harvested into a laboratory information-management system (LIMS), scored by crystal recognition software and displayed for user analysis via a web-based interface. Currently, storage for trials at 277,K is not automated and for imaging the crystallization plates are fed by hand into an imaging system from which the data enter the LIMS. The workflow includes two procedures for nanolitre-scale optimization of crystallization conditions: (i) a protocol for variation of pH, reservoir dilution and protein:reservoir ratio and (ii) an additive screen. Experience based on 592 crystallization projects is reported. [source] Structures of an alanine racemase from Bacillus anthracis (BA0252) in the presence and absence of (R)-1-aminoethylphosphonic acid (l -Ala-P)ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2008Kinfai Au Bacillus anthracis, the causative agent of anthrax, has been targeted by the Oxford Protein Production Facility to validate high-throughput protocols within the Structural Proteomics in Europe project. As part of this work, the structures of an alanine racemase (BA0252) in the presence and absence of the inhibitor (R)-1-aminoethylphosphonic acid (l -Ala-P) have determined by X-ray crystallography to resolutions of 2.1 and 1.47,Å, respectively. Difficulties in crystallizing this protein were overcome by the use of reductive methylation. Alanine racemase has attracted much interest as a possible target for anti-anthrax drugs: not only is d -alanine a vital component of the bacterial cell wall, but recent studies also indicate that alanine racemase, which is accessible in the exosporium, plays a key role in inhibition of germination in B. anthracis. These structures confirm the binding mode of l -Ala-P but suggest an unexpected mechanism of inhibition of alanine racemase by this compound and could provide a basis for the design of improved alanine racemase inhibitors with potential as anti-anthrax therapies. [source] Sequencing material handling equipment in production facilitiesINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 4 2007Manolis N. Kritikos Abstract In this article we consider the problem of sequencing material handling equipment in manufacturing systems, subject to constraints that restrict the start and end time of each production activity, according to pre-specified daily resource operational schedules and process planning information. The underlying decision problem is modeled using an integer programming formulation similar to vehicle routing with time windows (VRPTW). To take advantage of standard approaches for the VRPTW, we develop a transformation schema that allows a one-to-one mapping between the manufacturing problem and VRPTW. An efficient heuristic to solve the resulting transformed problem is proposed. The method, which is a penalty-based sequential insertion heuristic, allows routes to be constructed by exploiting the tradeoff between material handling and resource starvation costs. The steps of the method are illustrated via a comprehensive example and results on benchmark problems are reported. [source] Flavor Variability and Flavor Stability of U.S.-Produced Whole Milk PowderJOURNAL OF FOOD SCIENCE, Issue 7 2009M.A. Lloyd ABSTRACT:, Flavor variability and stability of U.S.-produced whole milk powder (WMP) are important parameters for maximizing quality and global competitiveness of this commodity. This study characterized flavor and flavor stability of domestic WMP. Freshly produced (<1 mo) WMP was collected from 4 U.S. production facilities 5 times over a 1 y period. Each sample was analyzed initially and every 2 mo for sensory profile, volatiles, color, water activity, and moisture through 12 mo storage. Selected volatiles were quantified using solid phase microextraction (SPME) with gas chromatography/mass-spectrometry: dimethyl sulfide, 2-methylbutanal, 3-methylbutanal, hexanal, 2-heptanone, heptanal, 1-octen-3-ol, octanal, 3-octen-2-one, and nonanal. Multiple linear regression with backwards elimination was applied to generate equations to predict grassy and painty flavors based on selected volatiles. All WMP were between 2% and 3% moisture and 0.11 and 0.25 water activity initially. WMP varied in initial flavor profiles with varying levels of cooked, milk fat, and sweet aromatic flavors. During storage, grassy and painty flavors developed while sweet aromatic flavor intensities decreased (P,< 0.05). Painty and grassy flavors were confirmed by increased levels (P,< 0.05) of lipid oxidation products such as hexanal, heptanal, and octanal. Hexanal, 2-heptanone, 1-octen-3-ol, and nonanal concentrations were best predictors of grassy flavor (R2= 0.38,,P,< 0.0001) while hexanal, 2-methylbutanal, 3-methylbutanal, octanal, and 3-octen-2-one concentrations were best predictors of painty flavor (R2= 0.61,,P,< 0.0001). These results provide baseline information to determine specific factors that can be controlled to optimize U.S. WMP flavor and flavor stability. [source] Evaluation of metaflumizone granular fly bait for management of housefliesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2009A. AHMAD Abstract The housefly, Musca domestica L. (Diptera: Muscidae), is a pest of great veterinary and public health importance. In this study, the efficacy of metaflumizone granular fly bait was assessed on first generation (F1) housefly adults raised from flies collected at a cattle feedlot in Kansas. All bioassays were conducted as choice tests, with flies having ad libitum access to water, granular sugar and bait. A commercial methomyl-based bait (Golden MalrinTM) was used as positive control; no bait (water and granular sugar only) was used as negative control. Fly mortality was recorded on days 2, 7 and 14. The metaflumizone bait was significantly more slow-acting than the methomyl bait (mortality rates after 2 days of exposure were 49.9% and 57.9%, respectively). However, there were no significant differences in cumulative mortality later in the bioassays. Cumulative mortality rates on days 7 and 14 were 96.1% (metaflumizone), 91.4% (methomyl) and 99.0% (metaflumizone), 97.6% (methomyl), respectively. Our results demonstrate that the metaflumizone granular fly bait may be an effective modality for incorporation into management programmes for houseflies in and around livestock production facilities as well as in residential settings. [source] Production of antibodies in plants: status after twenty yearsPLANT BIOTECHNOLOGY JOURNAL, Issue 5 2010Benoit De Muynck Summary Thanks to their potential to bind virtually all types of molecules; monoclonal antibodies are in increasing demand as therapeutics and diagnostics. To overcome the overloading of current production facilities, alternative expression systems have been developed, of which plants appear the most promising. In this review, we focus on the expression of monoclonal IgG or IgM in plant species. We analyse the data for 32 different antibodies expressed in various ways, differing in DNA construction, transformation method, signal peptide source, presence or absence of an endoplasmic reticulum retention sequence, host species and the organs tested, together resulting in 98 reported combinations. A large heterogeneity is found in the quantity and quality of the antibody produced. We discuss in more detail the strategy used to express both chains, the nature of the transcription promoters, subcellular localization and unintended proteolysis, when encountered. [source] The Influence of Knowledge Accumulation on Buyer-Supplier Codevelopment ProjectsTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 5 2003Melissa M. Appleyard This article investigates innovation across a supply chain and considers how knowledge accumulation as a consequence of buyer-supplier codevelopment projects can influence the projects' specifications. The setting is the semiconductor industry, and the players are chip producers who cooperate with their suppliers to modify their manufacturing equipment used to produce new semiconductor devices. Two detailed case studies were undertaken to determine the tradeoffs encountered by the buyer and supplier when setting the parameters that govern codevelopment projects. The findings from the case studies inform a conceptual framework that outlines the net payoffs to buyers when deciding whether to "make" or "buy" their production equipment. If buyers pursue the "make" option, they then have to decide the degree to which they sponsor modifications tailored to their production processes or modifications more generally applicable across the industry. More generally applicable modifications likely would prompt suppliers to invest relatively more in follow-on knowledge creation for upgrades and field support while leading to lower equipment costs due to economies of scale from larger production runs of the new equipment. The framework suggests that when making this sequence of decisions, an innovative buyer also weighs the importance of codevelopment for securing intellectual property rights, guaranteeing early access to new equipment enabling early product launch, and achieving high production yields quickly due to "previewing" the equipment. The conceptual framework leads to a multi-period model that focuses on the importance of knowledge accumulation for project parameterization. As captured by the model, buyers may prefer generally applicable modifications to customized ones, because generally applicable modifications may lead to greater knowledge accumulation at the supplier. This knowledge accumulation may be either "embodied" in equipment upgrades or "unembodied" in improved field support. In addition to shaping the nature of particular codevelopment projects, knowledge accumulation also may have profound implications for long-run industry structure. As seen in the semiconductor industry, knowledge accumulation at equipment suppliers has contributed to the rise of contract manufacturers, because these manufacturers can outfit their production facilities with equipment that embodies the accumulated knowledge. These findings suggest that for both short-run and long-run reasons, the dynamics of knowledge accumulation merit thorough attention when members of a supply chain cooperate during the course of new product development. [source] MULTIPLE FACILITIES, STRATEGIC SPLITTING AND VERTICAL STRUCTURES: STABILITY, GROWTH AND DISTRIBUTION RECONSIDERED,THE MANCHESTER SCHOOL, Issue 5 2006DAN COFFEY This paper explores comparative cost structures when large firms split operations between separate production facilities in a way that puts pressure on wage rates and worker effort levels: one example of a ,divide and rule' strategy. It differentiates horizontal structures of this kind based on requirements for stability in a context of growing aggregate production vis-à-vis wages and effort. The analysis is formulated within a more general perspective that also considers vertical structures. It considers the implications for contemporary policy debates on desirable industrial forms, and concludes with a discussion of factors that might limit the scope for policies intended to promote industrial stability and redistribution via existing production networks. [source] S39.2: Identification of an overreporting of allergic symptoms in relation to the distance to livestock production facilitiesBIOMETRICAL JOURNAL, Issue S1 2004Michael Hoopmann No abstract is available for this article. [source] Characterization of flow conditions in 2 L and 20 L wave bioreactors® using computational fluid dynamicsBIOTECHNOLOGY PROGRESS, Issue 1 2010Alper A. Öncül Abstract Characterization of flow conditions is of great importance to control cell growth and cell damage in animal cell culture because cell viability is influenced by the flow properties in bioreactors. Alternative reactor types like Wave Bioreactors® have been proposed in recent years, leading to markedly different results in cell growth and product formation. An advantage of Wave Bioreactors® is the disposability of the Polyethylenterephthalet-bags after one single use (fast setup of new production facilities). Another expected advantage is a lower shear stress compared to classical stirred-tank reactors, due to the gentle liquid motion in the rocking cellbag. This property would considerably reduce possible cell damage. The purpose of the present study is to investigate in a quantitative manner the key flow properties in Wave Bioreactors®, both numerically and experimentally. To describe accurately flow conditions and shear stress in Wave Bioreactors® using numerical simulations, it is necessary to compute the unsteady flow applying Computational Fluid Dynamics (CFD). Corresponding computations for two reactor scales (2 L and 20 L cellbags) are presented using the CFD code ANSYS-FLUENT®. To describe correctly the free liquid surface, the present simulations employ the Volume of Fluid (VOF) method. Additionally, experimental measurements have been carried out to determine liquid level, flow velocity and liquid shear stress, which are used as a validation of the present CFD simulations. It is shown that the obtained flows stay in the laminar regime. Furthermore, the obtained shear stress levels are well below known threshold values leading to damage of animal cells. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Bioprocess Engineering Issues That Would Be Faced in Producing a DNA Vaccine at up to 100 m3 Fermentation Scale for an Influenza PandemicBIOTECHNOLOGY PROGRESS, Issue 6 2005Mike Hoare The risk of a pandemic with a virulent form of influenza is acknowledged by the World Health Organization (WHO) and other agencies. Current vaccine production facilities would be unable to meet the global requirement for vaccine. As a possible supplement a DNA vaccine may be appropriate, and bioprocess engineering factors bearing on the use of existing biopharmaceutical and antibiotics plants to produce it are described. This approach addresses the uncertainty of timing of a pandemic that precludes purpose-built facilities. The strengths and weaknesses of alternative downstream processing routes are analyzed, and several gaps in public domain information are addressed. The conclusion is that such processing would be challenging but feasible. [source] Ecophysiology of the filamentous Alphaproteobacterium Meganema perideroedes in activated sludgeFEMS MICROBIOLOGY ECOLOGY, Issue 1 2005Caroline Kragelund Abstract A comprehensive study of the ecophysiology of the filamentous Meganema perideroedes affiliated to the Alphaproteobacteria, possessing a "Nostocoida limicola Type II" filamentous morphology was conducted. This morphotype often causes serious bulking problems in activated sludge wastewater treatment plants, and hardly anything is known about its physiology. The study was carried out by applying a suite of in situ methods in an industrial activated sludge treatment plant with excessive growth of this species. The experiments revealed a very versatile organism able to take up a large variety of organic substrates under aerobic conditions. It had a remarkably high storage capacity forming polyhydroxyalkanoates from most substrates tested. When nitrate was present as e-acceptor, the number of substrates to be consumed by M. perideroedes was more restricted compared to aerobic conditions. With nitrite as e-acceptor, only acetate and glucose among the substrates tested could be assimilated and used for storage and possibly growth. This indicated that M. perideroedes might be able to denitrify under certain conditions, which is unusual for filamentous bacteria in activated sludge. No substrate uptake or storage was seen under anaerobic conditions. M. perideroedes was relatively hydrophobic, compared to other filamentous bacteria and microcolonies present in the sludge, indicating the presence of a hydrophobic sheath. Several excreted surface-associated exoenzymes were detected in the sludge, but M. perideroedes never showed any activity, except once after a breakdown in the production facility. This confirmed that M. perideroedes mainly grows on soluble substrates. Based on the studies of the ecophysiology of M. perideroedes, potential control strategies are suggested. [source] Optimal machine capacity expansions with nested limitations under stochastic demandNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 2 2004Metin Çakany This paper studies capacity expansions for a production facility that faces uncertain customer demand for a single product family. The capacity of the facility is modeled in three tiers, as follows. The first tier consists of a set of upper bounds on production that correspond to different resource types (e.g., machine types, categories of manpower, etc.). These upper bounds are augmented in increments of fixed size (e.g., by purchasing machines of standard types). There is a second-tier resource that constrains the first-tier bounds (e.g., clean room floor space). The third-tier resource bounds the availability of the second-tier resource (e.g., the total floor space enclosed by the building, land, etc.). The second and third-tier resources are expanded at various times in various amounts. The cost of capacity expansion at each tier has both fixed and proportional elements. The lost sales cost is used as a measure for the level of customer service. The paper presents a polynomial time algorithm (FIFEX) to minimize the total cost by computing optimal expansion times and amounts for all three types of capacity jointly. It accommodates positive lead times for each type. Demand is assumed to be nondecreasing in a "weak" sense. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. [source] Inventory cost impact of order processing priorities based on demand uncertaintyNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 4 2002Ananth. Abstract We evaluate an approach to decrease inventory costs at retail inventory locations that share a production facility. The retail locations sell the same product but differ in the variance of retail demand. Inventory policies at retail locations generate replenishment orders for the production facility. The production facility carries no finished goods inventory. Thus, production lead time for an order is the sojourn time in a single server queueing system. This lead time affects inventory costs at retail locations. We examine the impact of moving from a First Come First Served (FCFS) production rule for orders arriving at the production facility to a rule in which we provide non-preemptive priority (PR) to orders from retail locations with higher demand uncertainty. We provide three approximations for the ratio of inventory costs under PR and FCFS and use them to identify conditions under which PR decreases retail inventory costs over FCFS. We then use a Direct Approach to establish conditions when PR decreases retail inventory costs over FCFS. We extend the results to orders from locations that differ in the mean and variance of demand uncertainty. The analysis suggests that tailoring lead times to product demand characteristics may decrease system inventory costs. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 376,390, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10016 [source] Geophysical Investigation at the Falling Creek Ironworks, an Early Industrial Site in VirginiaARCHAEOLOGICAL PROSPECTION, Issue 4 2001Geoffrey Jones Abstract A geophysical investigation was conducted at the site of the Falling Creek Ironworks (1619,1622), the first iron production facility in North America. Electrical resistance and magnetic field gradient surveys were conducted over the site of the seventeenth century ironworks. Additionally, ground-penetrating radar was used to investigate areas under an existing roadway. Linear and rectangular anomalies that appear in the resistance data may be caused by architectural features, possibly shops or domestic structures associated with the ironworks. Several low-amplitude magnetic anomalies that appear in the data appear to be cultural in origin, and may be caused by features associated with the ironworks. A number of high-amplitude magnetic anomalies appear in the magnetic field gradient data that are thought to be associated with iron production, including extensive slag deposits and the possible location of the blast furnace. Ground-penetrating radar data shows an anomalous reflection in the vicinity of the suspected blast furnace, which is partially beneath the modern roadway. Copyright © 2001 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||