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Entire Process (entire + process)
Selected AbstractsA novel approach for analysis of oligonucleotide,cisplatin interactions by continuous elution gel electrophoresis coupled to isotope dilution inductively coupled plasma mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometryELECTROPHORESIS, Issue 7 2008Wolfram Brüchert Abstract In this work we present a novel approach for in vitro studies of cisplatin interactions with 8-mer oligonucleotides. The approach is based on the recently developed coupling of continuous elution gel electrophoresis (GE) to an inductively coupled plasma-sector field mass spectrometer (ICP-SFMS) with the aim of monitoring the interaction process between this cytostatic drug and the nucleotides. In contrast to existing methods, the electrophoretic separation conditions used here allow both the determination of the reaction kinetics in more detail as well as the observation of dominant intermediates. Two different nucleotides sequences have been investigated for comparison purposes, one containing two adjacent guanines (5,-TCCGGTCC-3,) and one with a combination of thymine and guanine (5,-TCCTGTCC-3,), respectively. In order to gain further structural information, MALDI-TOF MS measurements have been performed after fraction collection. This allows for identification of the intermediates and the final products and confirms the stepwise coordination of cisplatin via monoadduct to bisadduct formation. Furthermore, the ICP-MS results were quantitatively evaluated in order to calculate the kinetics of the entire process. [source] Ab initio Emulsion Polymerization by RAFT (Reversible Addition,Fragmentation Chain Transfer) through the Addition of CyclodextrinsHELVETICA CHIMICA ACTA, Issue 8 2006Bojana Apostolovic Abstract A novel process to produce homo- and copolymers by RAFT polymerization in emulsion is presented. It is known that RAFT-controlled radical polymerization can be conducted in emulsion polymerization without disturbing the radical segregation characteristic of this process, thus leading to polymerization rates identical to those encountered in the corresponding nonliving systems. However, RAFT agents are often characterized by very low water solubility and, therefore, they diffuse very slowly from the monomer droplets, where they are initially solubilized, to the reaction loci, i.e., the polymer particles. Accordingly, when used in emulsion polymerization, they are practically excluded from the reaction. In this work, we show that cyclodextrins, well-known for their ability to form water-soluble complexes with hydrophobic molecules, facilitate the transport across the H2O phase of the RAFT agent to the polymer particles. Accordingly, chains grow through the entire process in a controlled way. This leads to the production of low-polydispersity polymers with well-defined structure and end functionalities as well as to the possibility of synthesizing block copolymers by a radical mechanism. [source] Cell Lysis of Cyanobacteria and Its Implications for Nutrient DynamicsINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2010Linlin Ye Abstract The dynamics of nutrients, such as phosphorus, nitrogen, and carbohydrates, during cyanobacteria cell lysis was investigated under darkness incubation in the laboratory. The cell lysis rate of cyanobacteria sampled from Lake Taihu was measured using an esterase assay. Based on particulate esterase activity, the calculated cyanobacteria lysis rate was 0.094 d,1. During 30 days of darkness incubation, Chlorophyll a concentration decreased from 56 ,g L,1 to 2.0 ,g L,1. Parallel to this, total particulate carbohydrate concentration decreased rapidly. The fluctuation of dissolved organic carbon concentration was a function of the production of non-carbohydrate by cyanobacteria and the decomposition of carbohydrate by bacteria. Total dissolved carbohydrates and dissolved polysaccharides concentrations showed a similar pattern, declining at the beginning of the experiment and keeping relatively stable, thereafter. In contrast, the concentration of dissolved monosaccharides remained constant during the entire process. The concentrations of NH4+ and PO43, increased at the early stage, and then decreased afterwards. A gradual decrease in NO3, concentration after day 8 indicated that anaerobic conditions might be produced during the cell lysis process. The present results demonstrated cyanobacteria cell lysis has a big influence on the nutrient status of the surrounding water. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Simulation of injection-compression molding process, Part 3: Effect of process conditions on part birefringenceADVANCES IN POLYMER TECHNOLOGY, Issue 3 2002Shia-Chung Chen Abstract Simulations of the injection-compression molding (ICM) process based on a Leonov viscoelastic fluid model has been employed to study the effects of processing conditions on the birefringence development and distribution in injection-compression molded parts. A numerical algorithm combined with a modified control-volume/finite-element method is developed to predict the melt front advancement and the distributions of pressure, temperature, and flow velocity dynamically during the injection melt-filling, compression melt-filling, and postfilling stages of the entire process. Part birefringence was then calculated from residual stresses following the thermal-mechanical history of the entire molding process. Simulations of a disk part under different process conditions including compression speed, switch time from injection to compression, compression stroke, packing pressure, and postfilling time were performed to understand their effects on birefringence variation. The simulated results were also compared with those required by conventional injection molding (CIM). It has been found that an ICM part shows a significant reduction of part birefringence near the gate area as compared with CIM parts. However, ICM parts exhibit higher birefringence values near the rim of the disk. The minimum birefringence occurs around the location where injection is switched over to compression. Although longer postfilling time and higher packing pressure result in higher birefringence values, their effects are not very significant. On the other hand, higher compression speed, larger compression stroke, and shorter switch time exhibit greater effects on the increase of part birefringence. Flow-induced residual stress is the major origin of birefringence formation in the present case. The simulated birefringence for both ICM and CIM parts show good coincidence with those obtained from measurements by using a digital photoelasticity technique. © 2002 Wiley Periodicals, Inc. Adv Polym Techn 21: 177,187, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/adv.10024 [source] Cognitive perturbation through dynamic modelling: a pedagogical approach to conceptual change in scienceJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 6 2006S. C. Li Abstract While simulations have widely been used to facilitate conceptual change in learning science, results indicate that significant disparity or gap between students' prior conceptions and scientific conceptions still exists. To bridge the gap, we argue that the applications of computer simulation in science education should be broadened to enable students to model their thoughts and to improve and advance their theories progressively. While computer simulations are often used to offer opportunities for students to explore scientific models, they do not give them the space to explore their own conceptions, and thus cannot effectively address the challenge of changing students' alternative conceptions. Findings from our recent empirical study reveal that, firstly, dynamic modelling using the environment WorldMaker 2000 in conjunction with the use of a cognitive perturbation strategy by the teacher was effective in helping students to migrate from their alternative conceptions towards a more scientifically inclined one; secondly, the pathways of conceptual change across groups were idiosyncratic and diverse. Respecting students' ideas seriously and providing cognitive perturbation at appropriate junctures of the inquiry process are found to be conducive to fostering conceptual change. In this paper, we will report on the details of the pedagogical approach adopted by the teacher and portray how students' conceptions change during the entire process of model building. [source] Ouch! , a logotherapeutic discourse of butch and tattooed in ChinaJOURNAL OF CONSUMER BEHAVIOUR, Issue 4 2010Wing-sun Liu This is a study of a small group of self-identified butch lesbians in their consumption of tattoos. The emotion-laden experience of negotiating social symbolism and self-identity (Elliott, 1997) in the context of hyperrealism (Baudrillard, 1983) has given rise to what Frankl (1984) has described as "existential vacuums." Frankl suggested that these "existential vacuums" can be filled with a higher level of meaning. An artifact of consumption, the tattoo, is used by the informants in this study as a component of bricolage in the DIY process of constructing a new self (Elliott, 1997), with the entire process of being tattooed , particularly the hyper-stimulation and pain of the procedure , further "existentializing" a new existence of "imagined masculinity." This new existence that transcends suffering and assigns new meaning to life is the principle idea of Frankl's logotherapy (Frankl, 1984; Barnes, 2000; Blair, 2004). Copyright © 2010 John Wiley & Sons, Ltd. [source] Method Development for Assessing the Complete Process of Crumbling Cheese Using Hand EvaluationJOURNAL OF FOOD SCIENCE, Issue 4 2004S. Sandra ABSTRACT: Cheese sensory evaluation was conducted by trained panelists (n= 8) on 4 commercial cheese samples (feta, Monterey Jack, 2 brands of Queso Fresco) in duplicate. Fifteen descriptors, capturing the entire process of crumbling cheese, were tested. Degree of crumbliness was defined as the ease by which the sample breaks apart during manipulation by rolling the sample using replicated circular movements, with the thumb, forefinger, and middle finger, 5 times. Using principal component analysis, 4 components were extracted and moistness, crumbliness, color, cohesiveness, irregularity, and oiliness were the main descriptors differentiating the samples. Panelists' performances were not significantly different (P, 0.05), and each subject used the method consistently for crumbliness. [source] The Role of Forensic Anthropology in the Examination of the Daegu Subway Disaster (2003, Korea),JOURNAL OF FORENSIC SCIENCES, Issue 3 2009Dae-Kyoon Park M.D., Ph.D. Abstract:, Meticulous recovery of victims in the Daegu subway disaster was possible, because charred and fragmented victims were left in situ. Because bodies were piled one over another within the train, appropriate methodology during the recovery was critical to identifying the victims. The disaster area was thoroughly documented with notes, photographs, and schematic drawings of the various locations. The recovery team, comprising two medical examiners and one forensic anthropologist, decided when charred body parts and cremated bones were linked to the same individual based on the anatomy and forensic anthropological examination. Without these recovery procedures, it would not have been possible to efficiently harvest representative DNA sample from most of the victims' body parts. After the entire process of identification, 136 victims were positively identified, and six victims remained unidentified. This study supports the crucial role of forensic anthropologists in the recovery of victims, especially in fire scenes. [source] Vacuum drying of wood with radiative heating: II.AICHE JOURNAL, Issue 1 2004Comparison between theory, experiment Abstract In part I of this work extensive experimental data sets for the vacuum drying of wood with radiative heating were presented for sapwood and heartwood of different species (Picea abies, Abies alba, and Fagus silvatica). These data sets are used here to validate two previously developed drying models. The first drying model, which is known as TransPore, is a comprehensive model able to capture the intricately coupled heat- and mass-transfer mechanisms that evolve throughout the drying process. The second model, which is known as Front_2D, uses a number of simplifying assumptions to reduce the complexity of the comprehensive model to a system that enables a semianalytical approach to be exploited for its solution. Although the first model provides a more accurate description of the entire process, the second model is able to produce representative solutions very efficiently in terms of overall computational times, making it a viable option for on-line control purposes. The comparison with experimental data highlights that both models are able to capture all of the observed trends, allowing them to be used with confidence for investigating the vacuum drying process at a fundamental level. The new contribution of this work lies in the fact that both models are used here for the first time to simulate drying at a reduced external pressure. © 2004 American Institute of Chemical Engineers AIChE J, 50: 108,118, 2004 [source] Extraction of pure lycopene from industrial tomato by-products in water using a new high-pressure processJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2008Daniele Naviglio Abstract BACKGROUND: Lycopene, a precursor of ,-carotene with a well-known antioxidant activity, contained in many natural products such as tomato (Lycopersicon esculentum Mill.), watermelon, red pepper and papaya, is usually recovered from natural vegetal sources using organic solvents and a purification step. In this paper an innovative process for the extraction of pure lycopene from tomato waste in water that uses the Naviglio® extractor and water as extracting phase is presented. RESULTS: Lycopene was obtained in the all- trans form at a very high grade of purity, not less than 98% (w/w), with an average recovery of 14% (w/w). The availability of high-purity trans -lycopene allowed measurement of the molar absorption coefficient. An alternative procedure for high-performance liquid chromatographic analysis using a phenyl-hexyl silicone phase as inverse phase and a linear gradient in water and acetonitrile is also described. CONCLUSIONS: The use of water as extracting phase considerably reduces the cost of the entire process when compared with the commonly used solvent-based procedure or with the newer supercritical extraction process of lycopene from tomato waste. Lycopene, not soluble in water, was recovered in a quasi-crystalline solid form and purified by solid-phase extraction using a small amount of organic solvent. Copyright © 2008 Society of Chemical Industry This article was published online on September 15, 2008. Errors in Figures 2 - 4 were subsequently identified. The publishers wish to apologise for these errors. This notice is included in the online and print versions to indicate that both have been corrected [September 19, 2008] [source] A petrologic study of the IAB iron meteorites: Constraints on the formation of the IAB-Winonaite parent bodyMETEORITICS & PLANETARY SCIENCE, Issue 6 2000G. K. BENEDIX These meteorites contain inclusions that fall broadly into five types: (1) sulfide-rich, composed primarily of troilite and containing abundant embedded silicates; (2) nonchondritic, silicate-rich, comprised of basaltic, troctolitic, and peridotitic mineralogies; (3) angular, chondritic silicate-rich, the most common type, with approximately chondritic mineralogy and most closely resembling the winonaites in composition and texture; (4) rounded, often graphite-rich assemblages that sometimes contain silicates; and (5) phosphate-bearing inclusions with phosphates generally found in contact with the metallic host. Similarities in mineralogy and mineral and O-isotopic compositions suggest that IAB iron and winonaite meteorites are from the same parent body. We propose a hypothesis for the origin of IAB iron meteorites that combines some aspects of previous formation models for these meteorites. We suggest that the precursor parent body was chondritic, although unlike any known chondrite group. Metamorphism, partial melting, and incomplete differentiation (i.e., incomplete separation of melt from residue) produced metallic, sulfide-rich and silicate partial melts (portions of which may have crystallized prior to the mixing event), as well as metamorphosed chondritic materials and residues. Catastrophic impact breakup and reassembly of the debris while near the peak temperature mixed materials from various depths into the re-accreted parent body. Thus, molten metal from depth was mixed with near-surface silicate rock, resulting in the formation of silicate-rich IAB iron and winonaite meteorites. Results of smoothed particle hydrodynamic model calculations support the feasibility of such a mixing mechanism. Not all of the metal melt bodies were mixed with silicate materials during this impact and reaccretion event, and these are now represented by silicate-free IAB iron meteorites. Ages of silicate inclusions and winonaites of 4.40-4.54 Ga indicate this entire process occurred early in solar system history. [source] Next-generation sequencing and metagenomic analysis: a universal diagnostic tool in plant virologyMOLECULAR PLANT PATHOLOGY, Issue 4 2009IAN P. ADAMS SUMMARY A novel, unbiased approach to plant viral disease diagnosis has been developed which requires no a priori knowledge of the host or pathogen. Next-generation sequencing coupled with metagenomic analysis was used to produce large quantities of cDNA sequence in a model system of tomato infected with Pepino mosaic virus. The method was then applied to a sample of Gomphrena globosa infected with an unknown pathogen originally isolated from the flowering plant Liatris spicata. This plant was found to contain a new cucumovirus, for which we suggest the name ,Gayfeather mild mottle virus'. In both cases, the full viral genome was sequenced. This method expedites the entire process of novel virus discovery, identification, viral genome sequencing and, subsequently, the development of more routine assays for new viral pathogens. [source] Using technology and innovation for planning social and economic transformation in a region of MexicoPERFORMANCE IMPROVEMENT QUARTERLY, Issue 2 2009Gonzalo Rodríguez Villanueva This article shows the possibility of achieving social transformation by applying the triple helix model, which establishes the university's participation and its research centers, the government and its three levels, and the private sector (Etzkowitz, 2002). These three allies have shared the vision and participated during the entire process, where the main focus is to increase development opportunities for the inhabitants of the southern region of Sonora, mainly from five elements: (1) creating an innovative regional system; (2) supporting creation of productive chains; (3) prioritizing investment in technology, information, and transport to improve territorial integration; (4) creating a safe and healthy environment where investments can be made; and (5) developing a government model based on a state policy and administered by projects. The methodology to create a regional plan for Southern Sonora is considered. [source] Economical Advantages of Low-Pressure Plasma Polymerization CoatingPLASMA PROCESSES AND POLYMERS, Issue 6 2005Hirotsugu Yasuda Abstract Summary: Low-pressure plasma polymerization coating, as described in this paper, is an ultimately green process that uses a minimum amount of substances and produces a minimum amount of effluent and hence does not require an environmental remediation process. The super-green aspect of the processing entirely changes the equation for the viability of the process in industrial applications. The main hampering factors for the low-pressure processes are 1) psychological fear of vacuum processes, 2) relatively high initial equipment costs, and 3) a lack of adequate cost estimate for the entire process. In many cases, the first two factors are enough for planners to shy away from this promising technology. However, when one examines the overall cost of processing as a whole, the cost of initial equipment often is not the decisive factor. Such cases are presented in the nano-film coating applied in corrosion protection of aluminum alloys, steel, and surface-state modification of contact lenses. The benefits of environmental friendliness, non-hazardous processing and superior performance of products that can be achieved only by low-pressure plasma polymerization coatings are more than enough to compensate the initial cost of the equipment. For nanofilm (20 nm) coatings, the most expensive annual operation cost is for wastewater treatment, which is much more than the initial cost of vacuum plasma polymerization reactor. [source] Pathways for the Non-CO-Involved Oxidation of Methanol on Pt(111)CHEMPHYSCHEM, Issue 14 2008Wang Gao Dr. Abstract The non-CO-involved oxidation of methanol (NCOIOM) on a Pt(111) surface is investigated by using density functional theory. Relative energy diagrams for the NCOIOM are established in which the reaction mechanisms for a catalytic cycle,including the associated barriers, the reactive energies, the intermediates, and the transient states,are shown. The results indicate that the reaction proceeds via the kinetically favored pathways: A) HCOH,HC(OH)2,HCOOH,HCOO- [-COOH],CO2 and B) CHO,HCOOH,HCOO- [-COOH],CO2, with OH playing a key role in the entire process. The vibrational frequencies of the intermediate states derived from the calculations are in agreement with the experimental measurements. [source] | ||||||||||||||||