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Resulting Products (resulting + products)
Selected AbstractsScene Graph and Frame Update Algorithms for Smooth and Scalable 3D Visualization of Simulated Construction OperationsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2002Vineet R. Kamat One of the prime reasons inhibiting the widespread use of discrete-event simulation in construction planning is the absence of appropriate visual communication tools. Visualizing modeled operations in 3D is arguably the best form of communicating the logic and the inner working of simulation models and can be of immense help in establishing the credibility of analyses. New software development technologies emerge at incredible rates that allow engineers and scientists to create novel, domain-specific applications. The authors capitalized on a computer graphics technology based on the concept of the scene graph to design and implement a general-purpose 3D visualization system that is simulation and CAD-software independent. This system, the Dynamic Construction Visualizer, enables realistic visualization of modeled construction operations and the resulting products and can be used in conjunction with a wide variety of simulation tools. This paper describes the scene graph architecture and the frame updating algorithms used in designing the Dynamic Construction Visualizer. [source] Identification and quantification of in vitro adduct formation between protein reactive xenobiotics and a lysine-containing model peptideENVIRONMENTAL TOXICOLOGY, Issue 1 2003Peter Reichardt Abstract Formation of in vitro adducts between different classes of xenobiotics and the lysine-containing peptide Lys-Tyr was monitored by high-performance liquid chromatography and electrospray ionization mass spectrometry. The molecular structures of the main resulting products could be sensitively analyzed by mass spectrometry (flow injection analysis), enabling the detection of characteristic binding formations. Aldehydes such as formaldehyde, acetaldehyde, and benzaldehyde were shown to form stable linkages to lysine amino groups via Schiff bases. Other electrophilic substances (e.g., toluene-2,4-diisocyanate, 2,4-dinitro-1-fluorobenzene, 2,4,6-trinitrobenzene sulfonic acid, dansyl chloride, and phthalic acid anhydride) also formed covalent adducts with lysine residues. The reactivity of the compounds was quantified by measuring the amount of peptide that remained unchanged after incubation for a certain period with the xenobiotic. Although reactivity levels within this group of aldehydes varied only to a small extent, as would be expected, extreme differences were seen among the structurally heterogeneous group of nonaldehyde xenobiotics. These results support the hypothesis that simple chemical reactions may lead to the adduction of nucleophilic macromolecules such as peptides or proteins. Such reactions, in particular, Schiff base formation of aldehydes, have previously been shown to be capable of specifically interfering with costimulatory signaling on T cells. Our results suggest that electrophilic xenobiotics of other classes may also inherit the capacity to exert similar effects. Forming covalent linkage to peptides may represent a possible molecular mechanism of electrophilic xenobiotics in vivo, yielding immunotoxic effects. The model utilized in this study is appropriate for monitoring the adduction of xenobiotics to basic peptides and for analyzing the resulting molecular structures. © 2003 Wiley Periodicals, Inc. Environ Toxicol 18: 29,36, 2003. [source] Microporous Silica Hollow Microspheres and Hollow Worm-Like Materials: A Simple Method for Their Synthesis and Their Application in Controlled ReleaseEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2010Mingwei Zhao Abstract Hollow silica microspheres and hollow worm-like materials were synthesized by using a simple method with the aid of 1-dodecyl-3-methylimidazolium bromide (C12mimBr). Hollow silica microspheres were initially produced by utilizing the combination of evaporation and an emulsion template. At a longer mixing time, the microspheres fused to form hollow worm-like silica materials due to the fusion of the emulsion templates. The resultant silica materials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and nitrogen adsorption/desorption. Both the hollow silica microspheres and the hollow worm-like materials are microporous. On the basis of experimental observations and the resulting products, a plausible formation mechanism is proposed. Preliminary tests demonstrate that the hollow silica microspheres and worm-like materials are capable of being loaded with Rhodamine B and releasing it, thus showing a great potential in controlled delivery applications. [source] Folding of epidermal growth factor-like repeats from human tenascin studied through a sequence frame-shift approachFEBS JOURNAL, Issue 21 2004Francesco Zanuttin In order to investigate the factors that determine the correct folding of epidermal growth factor-like (EGF) repeats within a multidomain protein, we prepared a series of six peptides that, taken together, span the sequence of two EGF repeats of human tenascin, a large protein from the extracellular matrix. The peptides were selected by sliding a window of the average length of tenascin EGF repeats over the sequence of EGF repeats 13 and 14. We thus obtained six peptides, EGF-f1 to EGF-f6, that are 33 residues long, contain six cysteines each, and bear a partial overlap in the sequence. While EGF-f1 corresponds to the native EGF-14 repeat, the others are frame-shifted EGF repeats. We carried out the oxidative folding of these peptides in vitro, analyzed the reaction mixtures by acid trapping followed by LC-MS, and isolated some of the resulting products. The oxidative folding of the native EGF-14 peptide is fast, produces a single three-disulfide species with an EGF-like disulfide topology and a marked difference in the RP-HPLC retention time compared with the starting product. On the contrary, frame-shifted peptides fold more slowly and give mixtures of three-disulfide species displaying RP-HPLC retention times that are closer to those of the reduced peptides. In contrast to the native EGF-14, the three-disulfide products that could be isolated are mainly unstructured, as determined by CD and NMR spectroscopy. We conclude that both kinetics and thermodynamics drive the correct pairing of cysteines, and speculate about how cysteine mispairing could trigger disulfide reshuffling in vivo. [source] OSMOTIC DEHYDRATION OF MUSKMELON (CUCUMIS MELO): INFLUENCE OF BLANCHING AND SYRUP CONCENTRATIONJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2007RENZO M. FERNANDEZ ABSTRACT The influence of blanching and syrup concentration on the quality parameters of osmo-air-dried muskmelon product was investigated. Fruit samples were dehydrated with sucrose solutions at 40, 50 and 60°Brix and the resulting products were analyzed for browning degree, ascorbic acid (AA) concentration and water activity. The values for all three parameters decreased as the syrup concentration increased. Blanching treatment before the osmotic processing had no effect on browning but caused a decrease in AA concentration. Osmotically dehydrated fruits showed no browning increase for at least 4 weeks at 2C. A decrease of about 60% in AA concentration was observed within the first 2 weeks at 10C. In contrast, AA loss was only observed after 2 weeks at 2C. The influence of storage time and temperature on AA retention was investigated by 22 factorial design. Statistical analysis of results showed that the two factors have a significant effect on AA retention. Osmotic dehydration may be an interesting alternative for processing of muskmelon as a pretreatment followed by cold storage or drying. [source] A novel prohormone processing site in Aplysia californica: the Leu,Leu ruleJOURNAL OF NEUROCHEMISTRY, Issue 6 2002Amanda B. Hummon Abstract Neuropeptides are a complex set of signaling molecules produced through enzymatic cleavages from longer prohormone sequences. The most common cleavage sites in prohormones are basic amino acid residues; however, processing is observed at non-basic sites. Cleavage at Leu,Leu sequences has been observed in three Aplysia californica prohormones. To further investigate this unusual event, native and non-native synthetic peptides containing Leu,Leu residues are incubated with homogenates of Aplysia californica ganglia and the resulting products monitored with MALDI MS. Cleavage near and between Leu,Leu residues is observed in the abdominal and buccal ganglia homogenates, confirming the presence of an unidentified peptidase. In addition, fractions from an HPLC separation of buccal ganglia homogenates also produce cleavages at Leu,Leu residues. Products resulting from cleavage at Leu,Leu sites are observed and are produced in larger amounts in acidic and neutral pH ranges, and cleavage is inhibited by the addition of EDTA, suggesting a metal is required for activity. [source] Febrile seizures are associated with mutation of seizure-related (SEZ) 6, a brain-specific geneJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2007Zhi-liang Yu Abstract Genetic factors contribute significantly to the etiology of febrile seizures (FS), the most common type of seizures in childhood. However, in most patients with FS, the causative gene is unknown. The purpose of this study was to explore the relationship between human brain-specific gene SEZ-6 and FS. Through amplification of genomic DNA by PCR and sequencing of the resulting products, we screened 75 subjects for mutations in the coding region (17 exons) of the SEZ-6 gene. Fifteen subjects were healthy individuals and 60 subjects had FS. Patients with FS could be divided into sub-groups based on seizure type (42 simple and 18 complex) and family history (41 had a positive family history). All patients have been followed to date to evaluate seizure recurrence and the development of epilepsy. No mutations were found in healthy controls, but 21 of the patients with FS had mutations in SEZ-6, and the most common type of mutation was a heterozygous, cytosine insertion (frame shift mutation) at position 1435 of the cDNA. The mutation incidence was significantly higher in patients with complex FS (vs. simple FS) and in patients with a positive family history. Sixteen of 42 patients with simple FS experienced seizure recurrence during the 1,5-year follow-up period. Fifteen of 18 patients with complex FS also experienced a recurrence during this period. Among these patients with recurrences, five patients with simple FS and six patients with complex FS have developed epilepsy. The mutation incidence among these epileptic patients is 72.7%. The human SEZ-6 gene is related to the occurrence and development of FS and may be a novel candidate gene for epilepsy. Screening for mutations in SEZ-6 may be valuable in predicting FS recurrence or the development of epilepsy. © 2006 Wiley-Liss, Inc. [source] Functionalized multi-walled carbon nanotubes with poly(N -(2-hydroxypropyl)methacrylamide) by RAFT polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 8 2006Chun-Yan Hong Abstract In this study, we grafted water-soluble biocompatible polymer, poly(N -(2-hydroxypropyl)methacrylamide) (PHPMA), onto the surface of multi-walled carbon nanotubes (MWNTs). The reversible addition-fragmentation chain transfer (RAFT) agents, dithioesters, were successfully immobilized onto the surface of MWNTs first, PHPMA chains were then subsequently grafted onto MWNTs via RAFT polymerization by using dithioesters immobilized on MWNTs as RAFT agent. FTIR, XPS, 1H NMR, Raman and TGA were used to characterize the resulting products and to determine the content of water-soluble PHPMA chains in the product. The MWNTs grafted with PHPMA chains have good solubility in distilled water, PBS buffer, and methanol. TEM images of the samples provide direct evidence for the formation of a nanostructure that MWNTs coated with polymer layer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2419,2427, 2006 [source] Sintering Temperature Dependence of Thermoelectric Performance and Crystal Phase of Calcium Cobalt OxidesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2010Masahiro Tahashi Polycrystalline samples were synthesized by a conventional solid-state reaction. As starting materials, Co3O4 and Ca(OH)2 were mixed in a molar ratio of Ca:Co=3:4 and sintered at 1073,1373 K. The compound phases and thermoelectric properties of the resulting products were dependent on the sintering temperature. X-ray diffraction analysis showed that the Ca3Co4O9 compound was stable up to 1193 K and that Ca3Co2O6 was formed at 1273 K. At 1373 K, the sample decomposed into cobalt oxide and calcium oxide. A maximum power factor of about 100 ,W/(K2·m) at 873 K was obtained for the Ca3Co4O9 phase sintered at 1193 K. [source] The Role of Allylanisole in Metallocene-Catalyzed Propylene Polymerization and Synthesis of End-Capped OligomersMACROMOLECULAR REACTION ENGINEERING, Issue 4 2008Muhammad Atiqullah Propylene was copolymerized with allylanisole (AA) using Me2Si(Ind)2ZrCl2 and Et(Ind)2ZrCl2, and the methylaluminoxane MAO cocatalyst at 70,°C and a cocatalyst to catalyst (Al:Zr) molar ratio of 1,000. It was fed at 8.5 bar(g). The weight-average molecular weight, , for both metallocenes decreased as the AA feed concentration increased. Therefore, allylanisole acted as an in situ chain transfer agent. The chain transfer constants, ktr/kp, of AA for Et(Ind)2ZrCl2 and Me2Si(Ind)2ZrCl2 turned out to be 0.33 and 0.40, respectively. The characterization of the resulting products by 1H NMR demonstrated that AA end-capped the isotactic poly(propylene) chains which showed to be low molecular weight oligomers; 4.96,×,103,,,,,,9.80,×,103. An appropriate chain transfer mechanism for AA has been proposed. [source] Writing through time: longitudinal studies of the effects of new technology on writingBRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 2 2001James Hartley This paper contributes to the discussion about the effects of new technology on writing by assessing whether or not people's writing styles and ways of thinking change when new technologies are introduced. The writing styles of the three authors, prolific writers in their own fields, were assessed by comparing materials written by each author over a thirty-year period. During this time there were, for each author, great changes in the ways that they used new technology to help them to write. Nonetheless, the results indicated that, although the writing styles of each author differed from each other, their individual styles were remarkably consistent over time. These results thus suggest that although the new technologies may change the ways that individual writers work, they do not alter the styles of their resulting products. [source] Influence of the Charge State on the Structures and Interactions of Vancomycin Antibiotics with Cell-Wall Analogue Peptides: Experimental and Theoretical StudiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2009Zhibo Yang Dr. Abstract Charge matters! The charge state significantly influences the conformation and the binding energy between vancomycin antibiotic and bacterial cell-wall analogue peptides (see figure). Surface-induced dissociation (SID) studies provide a quantitative comparison between the stabilities of different charge states of the complex. In this study we examined the effect of the charge state on the energetics and dynamics of dissociation of the noncovalent complex between the vancomycin and the cell-wall peptide analogue N,,N, -diacetyl- L -Lys- D -Ala- D -Ala (V,Ac2LKdAdA). The binding energies between the vancomycin and the peptide were obtained from the RRKM (Rice, Ramsperger, Kassel, Marcus) modeling of the time- and energy-resolved surface-induced dissociation (SID) experiments. Our results demonstrate that the stability of the complex towards fragmentation increases in the order: doubly protonated
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