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Rapid Production (rapid + production)
Selected AbstractsRapid production of a plasmid DNA encoding a malaria vaccine candidate via amino-functionalized poly(GMA- co -EDMA) monolithAICHE JOURNAL, Issue 11 2008Michael K. Danquah Abstract Malaria is a global health problem; an effective vaccine is urgently needed. Due to the relative poverty and lack of infrastructure in malaria endemic areas, DNA-based vaccines that are stable at ambient temperatures and easy to formulate have great potential. While attention has been focused mainly on antigen selection, vector design and efficacy assessment, the development of a rapid and commercially viable process to manufacture DNA is generally overlooked. We report here a continuous purification technique employing an optimized stationary adsorbent to allow high-vaccine recovery, low-processing time, and, hence, high-productivity. A 40.0 mL monolithic stationary phase was synthesized and functionalized with amino groups from 2-Chloro-N,N-diethylethylamine hydrochloride for anion-exchange isolation of a plasmid DNA (pDNA) that encodes a malaria vaccine candidate, VR1020-PyMSP4/5. Physical characterization of the monolithic polymer showed a macroporous material with a modal pore diameter of 750 nm. The final vaccine product isolated after 3 min elution was homogeneous supercoiled plasmid with gDNA, RNA and protein levels in keeping with clinical regulatory standards. Toxicological studies of the pVR1020-PyMSP4/5 showed a minimum endotoxin level of 0.28 EU/mg pDNA. This cost-effective technique is cGMP compatible and highly scalable for the production of DNA-based vaccines in commercial quantities, when such vaccines prove to be effective against malaria. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] High-level distribution for the rapid production of robust telecoms software: comparing C++ and ERLANGCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2008J. H. Nyström Abstract Currently most distributed telecoms software is engineered using low- and mid-level distributed technologies, but there is a drive to use high-level distribution. This paper reports the first systematic comparison of a high-level distributed programming language in the context of substantial commercial products. Our research strategy is to reengineer some C++/CORBA telecoms applications in ERLANG, a high-level distributed language, and make comparative measurements. Investigating the potential advantages of the high-level ERLANG technology shows that two significant benefits are realized. Firstly, robust configurable systems are easily developed using the high-level constructs for fault tolerance and distribution. The ERLANG code exhibits resilience: sustaining throughput at extreme loads and automatically recovering when load drops; availability: remaining available despite repeated and multiple failures; dynamic reconfigurability: with throughput scaling near-linearly when resources are added or removed. Secondly, ERLANG delivers significant productivity and maintainability benefits: the ERLANG components are less than one-third of the size of their C++ counterparts. The productivity gains are attributed to specific language features, for example, high-level communication saves 22%, and automatic memory management saves 11%,compared with the C++ implementation. Investigating the feasibility of the high-level ERLANG technology demonstrates that it fulfils several essential requirements. The requisite distributed functionality is readily specified, even although control of low-level distributed coordination aspects is abrogated to the ERLANG implementation. At the expense of additional memory residency, excellent time performance is achieved, e.g. three times faster than the C++ implementation, due to ERLANG's lightweight processes. ERLANG interoperates at low cost with conventional technologies, allowing incremental reengineering of large distributed systems. The technology is available on the required hardware/operating system platforms, and is well supported. Copyright © 2007 John Wiley & Sons, Ltd. [source] Protection of DNA during early development: adaptations and evolutionary consequencesEVOLUTION AND DEVELOPMENT, Issue 1 2003David Epel SUMMARY The rapidly dividing cleavage stages of embryos do not have the typical responses to cell damage, such as induction of the heat shock response, use of mitotic checkpoints, or use of apoptosis to eliminate severely damaged cells. This could create problems with integrity of DNA, but the solution in these embryos appears to be a "be prepared" approach, in which specific adaptations are used to minimize DNA damage during cleavage and the use of apoptosis at the mid-blastula transition to remove any cells that were nevertheless damaged. It has been assumed that this approach has evolved because of the advantage of rapid production of a motile larvae. Alternatively, this particular approach may have the selective advantage of increasing mutation rate when there are greater environmental stresses. This could provide more variants on which selective pressures could act and thus accelerate evolution during environmentally stressful periods. [source] High Breakdown Field Dielectric Elastomer Actuators Using Encapsulated Polyaniline as High Dielectric Constant FillerADVANCED FUNCTIONAL MATERIALS, Issue 19 2010Martin Molberg Abstract A novel method allowing rapid production of reliable composites with increased dielectric constant and high dielectric strength for dielectric elastomer actuators (DEA) is reported. The promising approach using composites of conductive particles and insulating polymers generally suffers from low breakdown fields when applied to DEA devices. The present publication shows how to overcome this deficiency by using conductive polyaniline (PANI) particles encapsulated into an insulating polymer shell prior to dispersion. PANI particles are encapsulated using miniemulsion polymerization (MP) of divinylbenzene (DVB). The encapsulation process is scaled up to approximately 20 g particles per batch. The resulting particles are used as high dielectric constant (,,) fillers. Composites in a polydimethylsiloxane (PDMS) matrix are prepared and the resulting films characterized by dielectric spectroscopy and tensile tests, and evaluated in electromechanical actuators. The composite films show a more than threefold increase in ,,, breakdown field strengths above 50 V ,m,1, and increased strain at break. These novel materials allow tuning the actuation strain or stress output and have potential as materials for energy harvesting. [source] Laser Spinning of Bioactive Glass NanofibersADVANCED FUNCTIONAL MATERIALS, Issue 19 2009Félix Quintero Abstract The production of nanofibers of bioactive glass by laser spinning is reported. The technique yields a great quantity of free-standing fibers in the form of a mesh of disordered intertwined fibers. The method does not rely on chemical processing and does not need any chemical additive. It involves melting of a precursor material with tailored composition, which makes it possible to produce nanofibers from materials with which conventional melt drawing techniques cannot be used. Herein, the production of 45S5 Bioglass nanofibers is reported for the first time. The process is very fast (nanofibers of several centimeters are grown in a fraction of a second), without the necessity of post heat treatments, and no devitrification is observed as a result of the laser-spinning process. The morphology, composition, and structure of the nanofibers are characterized and an assessment of their bioactivity is carried out by immersion in simulated body fluid. This technique provides a method for the rapid production of dense glass nanofibers that can be employed as bioactive nanocomposite reinforcement, as a synthetic bone graft to replace missing bone, or to produce 3D structures for use as scaffolds for bone-tissue engineering. [source] Metal Ion Implantation for the Fabrication of Stretchable Electrodes on ElastomersADVANCED FUNCTIONAL MATERIALS, Issue 3 2009Samuel Rosset Abstract Here, the use of low-energy metal ion implantation by filtered cathodic vacuum arc to create highly deformable electrodes on polydimethylsiloxane (PDMS) membranes is reported. Implantation leads to the creation of nanometer-size clusters in the first 50,nm below the surface. When the elastomer is stretched, these small clusters can move relative to one another, maintaining electrical conduction at strains of up to 175%. Sheet resistance versus ion dose, resistance versus strain, time stability of the resistance, and the impact of implantation on the elastomer's Young's modulus are investigated for gold, palladium, and titanium implantations. Of the three tested metals, gold has the best performance, combining low and stable surface resistance, very high strain capabilities before loss of electrical conduction, and low impact on the Young's modulus of the PDMS membrane. These electrodes are cyclically strained to 30% for more than 105 cycles and remain conductive. In contrast, sputtered or evaporate metals films cease to conduct at strains of order 3%. Additionally, metal ion implantation allows for creating semi-transparent electrodes. The optical transmission through 25-µm-thick PDMS membranes decreases from 90% to 60% for Pd implantations at doses used to make stretchable electrodes. The implantation technique presented here allows the rapid production of reliable stretchable electrodes for a number of applications, including dielectric elastomer actuators and foldable or rollable electronics. [source] Characterization of a broad pH range protease of Candida caseinolyticaJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2001M. Poza Aims:,The study of a protease secreted by Candida caseinolytica for use in future industrial applications. Methods and Results:,Growth of Candida caseinolytica on a medium containing milk induced a rapid production of an extracellular enzyme able to hydrolyse casein. The crude extract was applied to both Sephacryl S-200 and DEAE-Biogel A columns, obtaining one peak of activity showing a molecular mass of , 30 kDa and three active peaks, respectively. These four peaks showed the same biochemical parameters. In all cases, an extremely broad pH range of action was determined. Conclusions:,Candida caseinolytica secretes high levels of an extracellular protease when grown either in rotary shakers or in batch-fermenters. Significance and Impact of the Study:,The biochemical properties of this enzyme suggest its possible industrial application in the brewing industry, in the formulation of certain type of detergents and in the fur and leather industries, among others. [source] Rapid method for the preparation of an AGE-BSA standard calibrator using thermal glycationJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 1 2005A.D. Bhatwadekar Abstract Estimation of advanced glycation end products (AGEs) by determining fluorescence is based on the use of a standard calibrator prepared by incubating bovine serum albumin (BSA) and glucose at 37°C for 60 days. In the present study we attempted to reduce the duration of incubation to 4 days by increasing the temperature to 50°C. It is noteworthy that incubation at 50°C resulted in the rapid production of an AGE-BSA standard calibrator within 4 days. Aminoguanidine reduced the intensity of the glycation-induced fluorescence, while the addition of lysine intensified the reaction, as shown by the calibrator incubated at 37°C. The protein carbonyl content was shown to increase in the rapidly-formed standard calibrator. Thus we conclude that a simple increase in temperature and the addition of lysine (0.1M) can accelerate the process of glycation-induced fluorescence. This calibrator can be used effectively in fluorescence assays of AGEs. J. Clin. Lab. Anal. 19:11,15, 2005. © 2005 Wiley-Liss, Inc. [source] High-resolution real-time recording with microelectrode biosensors reveals novel aspects of adenosine release during hypoxia in rat hippocampal slicesJOURNAL OF NEUROCHEMISTRY, Issue 6 2003B. G. Frenguelli Abstract We have used improved miniaturized adenosine biosensors to measure adenosine release during hypoxia from within the CA1 region of rat hippocampal slices. These microelectrode biosensors record from the extracellular space in the vicinity of active synapses as they detect the synaptic field potentials evoked in area CA1 by stimulation of the afferent Schaffer collateral-commissural fibre pathway. Our new measurements demonstrate the rapid production of adenosine during hypoxia that precedes and accompanies depression of excitatory transmission within area CA1. Simultaneous measurement of adenosine release and synaptic transmission gives an estimated IC50 for adenosine on transmission in the low micromolar range. However, on reoxygenation, synaptic transmission recovers in the face of elevated extracellular adenosine and despite a post-hypoxic surge of adenosine release. This may indicate the occurrence of apparent adenosine A1 receptor desensitization during metabolic stress. In addition, adenosine release is unaffected by pharmacological blockade of glutamate receptors and shows depletion on repeated exposure to hypoxia. Our results thus suggest that adenosine release is not a consequence of excitotoxic glutamate release. The potential for adenosine A1 receptor desensitization during metabolic stress implies that its prevention may be beneficial in extending adenosine-mediated neuroprotection in a variety of clinically relevant conditions. [source] Spatial coordination of aluminium uptake, production of reactive oxygen species, callose production and wall rigidification in maize rootsPLANT CELL & ENVIRONMENT, Issue 7 2006D. L. JONES ABSTRACT Aluminium (Al) toxicity associated with acid soils represents one of the biggest limitations to crop production worldwide. Although Al specifically inhibits the elongation of root cells, the exact mechanism by which this growth reduction occurs remains controversial. The aim of this study was to investigate the spatial and temporal dynamics of Al migration into roots of maize (Zea mays L.) and the production of the stress response compound callose. Using the Al-specific fluorescent probe morin, we demonstrate the gradual penetration of Al into roots. Al readily accumulates in the root's epidermal and outer cortical cell layers but does not readily penetrate into the inner cortex. After prolonged exposure times (12,24 h), Al had entered all areas of the root apex. The spatial and temporal accumulation of Al within the root is similarly matched by the production of the cell wall polymer callose, which is also highly localized to the epidermis and outer cortical region. Exposure to Al induced the rapid production of reactive oxygen species and induced a significant rigidification of the cell wall. Our results suggest that Al-induced root inhibition in maize occurs by rigidification of the epidermal layers. [source] Preparation of strach-graft-polyacrylamide copolymers by reactive extrusion,POLYMER ENGINEERING & SCIENCE, Issue 10 2003J. L. Willett Graft copolymers of starch and polyacrylamide (PAAm) were prepared by reactive extrusion using a co-rotating twin-screw extruder and ammonium presulfate initiator. Feed rates were 109 g/min to 325 g/min (all components) at a moisture content of 50%, with screw speeds in the range 100 rpm to 300 rpm. Starch/acrylamide weight ratios ranged from 5:1 to 1.3:1. Conversions of acrylamide to PAAm were generally 80% or greater with residence times of 400 seconds or less. Conversion increased with feed rate, suggesting that reaction efficiency was proportional to the degree of fill in the extruder. Grafting efficiencies were in the range of 50% to 80%. PAAm molecular weight increased with increasing acrylamide content, consistent with free radical polymerization kinetics. Extrusion temperature had no significant impact on acrylamide conversion. Graft frequency, as measured by the number of anhydroglucose units per graft, was essentially constant over the starch: acrylamide ratio and temperature range studied. These results show that reactive extrusion offers the potential for rapid production of starch graft copolymers with unsaturated monomers. [source] | |||||||||||||