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Whole Process (whole + process)
Selected AbstractsHierarchical Convex Approximation of 3D Shapes for Fast Region SelectionCOMPUTER GRAPHICS FORUM, Issue 5 2008Marco Attene Abstract Given a 3D solid model S represented by a tetrahedral mesh, we describe a novel algorithm to compute a hierarchy of convex polyhedra that tightly enclose S. The hierarchy can be browsed at interactive speed on a modern PC and it is useful for implementing an intuitive feature selection paradigm for 3D editing environments. Convex parts often coincide with perceptually relevant shape components and, for their identification, existing methods rely on the boundary surface only. In contrast, we show that the notion of part concavity can be expressed and implemented more intuitively and efficiently by exploiting a tetrahedrization of the shape volume. The method proposed is completely automatic, and generates a tree of convex polyhedra in which the root is the convex hull of the whole shape, and the leaves are the tetrahedra of the input mesh. The algorithm proceeds bottom-up by hierarchically clustering tetrahedra into nearly convex aggregations, and the whole process is significantly fast. We prove that, in the average case, for a mesh of n tetrahedra O(n log2 n) operations are sufficient to compute the whole tree. [source] In vivo phosphorylation of regulatory light chain of myosin II in sea urchin eggs and its role in controlling myosin localization and function during cytokinesisCYTOSKELETON, Issue 2 2008Ryota Uehara Abstract Phosphorylation of myosin regulatory light chain (RLC) at Ser19 (mono-phosphorylation) promotes filament assembly and enhances actin-activated ATPase activity of non-muscle myosin, while phosphorylation at both Ser19 and Thr18 (di-phosphorylation) further enhances the ATPase activity. However, it has not well been addressed which type of phosphorylation is important in regulating myosin during cytokinesis. Here, we investigated subcellular localization in sea urchin eggs of mono-phosphorylated and di-phosphorylated RLC by both quantitative biochemical and spatiotemporal cytological approaches. Mono-phosphorylated RLC was dominant in the equatorial cortex throughout the whole process of cytokinesis. Inhibition of myosin light chain kinase (MLCK) decreased mono-phosphorylated RLC both in the cortex and in the cleavage furrow, and blocked both formation and contraction of the contractile ring. Two different types of ROCK inhibitor gave inconsistent results: H1152 blocked both RLC mono-phosphorylation in the cleavage furrow and contraction of the contractile ring, while Y27632 affected neither the mono-phosphorylation nor cell division. These results suggest that there may be other targets of H1152 than ROCK, which is involved in the RLC phosphorylation in the cleavage furrow. Furthermore, it was revealed that localization of myosin heavy chain in the cleavage furrow, but not in the cortex, was perturbed by inhibition of RLC mono-phosphorylation. These results suggested that RLC mono-phosphorylation by more than two RLC kinases play a main role in regulation and localization of myosin in the dividing sea urchin eggs. Cell Motil. Cytoskeleton 2007. © 2007 Wiley-Liss, Inc. [source] Poly(dimethylsiloxane)-based microfluidic device with electrospray ionization-mass spectrometry interface for protein identificationELECTROPHORESIS, Issue 21 2003Wang-Chou Sung Abstract An easy method to fabricate poly(dimethylsiloxane) (PDMS)-based microfluidic chips for protein identification by tandem mass spectrometry is presented. This microchip has typical electrophoretic microchannels, a flow-through sampling inlet, and a sheathless nanoelectrospray ionization (ESI) interface. The surface of the microchannel was modified with 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and the generated electroosmotic flow under acidic buffer condition used for the separation was found to be more stable compared to that generated by the microchannel without modification. The feasibility of the device for flow-through sampling, separation, and ESI-MS/MS analysis was demonstrated by the analysis of a standard mixture composed of three tryptic peptides. Results show that four peaks corresponding to three peptide standards and acetylated products of the standard peptide were well resolved and the deduced sequences were consistent with those expected. Furthermore, the compatibility of this device with other miniaturized devices to integrate the whole process was also explored by connecting a miniaturized enzymatic digestion cartridge and a desalting cartridge in series to the sampling inlet of the microchip for the identification of a model protein, ,-casein. [source] Solute transport in sand and chalk: a probabilistic approachHYDROLOGICAL PROCESSES, Issue 5 2006E. Carlier Abstract A probabilistic approach is used to simulate particle tracking for two types of porous medium. The first is sand grains with a single intergranular porosity. Particle tracking is carried out by advection and dispersion. The second is chalk granulates with intergranular and matrix porosities. Sorption can occur with advection and dispersion during particle tracking. Particle tracking is modelled as the sum of elementary steps with independent random variables in the sand medium. An exponential distribution is obtained for each elementary step and shows that the whole process is Markovian. A Gamma distribution or probability density function is then deduced. The relationships between dispersivity and the elementary step are given using the central limit theorem. Particle tracking in the chalky medium is a non-Markovian process. The probability density function depends on a power of the distance. Experimental simulations by dye tracer tests on a column have been performed for different distances and discharges. The probabilistic approach computations are in good agreement with the experimental data. The probabilistic computation seems an interesting and complementary approach to simulate transfer phenomena in porous media with respect to the traditional numerical methods. Copyright © 2006 John Wiley & Sons, Ltd. [source] Copper-Catalyzed N -Alkylation of Sulfonamides with Benzylic Alcohols: Catalysis and Mechanistic StudiesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17 2009Xinjiang Cui Abstract The N -alkylation of sulfonamides with alcohols is efficiently performed in the presence of easily available copper catalysts via hydrogen borrowing methodology. Applying a copper acetate/potassium carbonate system the reaction of sulfonamides and alcohols gave the corresponding secondary amines in excellent yield. In situ HR-MS analysis indicated that bissulfonylated amines are formed under air atmosphere, which act as self-stabilizing ligands for the catalytic system. UV-visible measurements suggest the interaction between the copper centre and the bissulfonylated amine. Reactions of benzyl alcohol- d7 with p -toluenesulfonamide, N -benzyl- p -toluenesulfonamide or N -benzylidenetoluenesulfonamide revealed that the reaction proceeds via a transfer hydrogenation mechanism and the whole process is micro-reversible. Competitive reactions of benzyl alcohol and benzyl alcohol- d7 with p -toluenesulfonamide revealed a kinetic isotope effect (kH/kD) of 3.287 (0.192) for the dehydrogenation of benzyl alcohol and 0.611 (0.033) for the hydrogenation of the N -benzylidene- p -toluenesulfonamide intermediate, which suggests that dehydrogenation of the alcohol is the rate-determining step. [source] One-Pot Conversion of Cephalosporin C to 7-Aminocephalosporanic Acid in the Absence of Hydrogen PeroxideADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14 2005Fernando Lopez-Gallego Abstract The main drawback in the production of 7-aminocephalosporanic acid (7-ACA) at the industrial level is the inactivation of the enzymes implicated in the process due to the presence of hydrogen peroxide during the reaction. As an alternative, we have developed the conversion of cephalosporin C to 7-ACA in a single reactor without the presence of hydrogen peroxide during the reaction, achieving more than 80% yield. In order to develop this process, D -amino acid oxidase (DAAO) was co-immobilized with catalase (CAT), which is able to fully eliminate in situ the hydrogen peroxide formed by the neighbouring DAAO molecules. Thus, the product of the reaction is only ,-ketoadipyl-7-ACA. This system prevents the inactivation of the oxidase by hydrogen peroxide, solving the main problem of the enzymatic process. Moreover, we have found that ,-ketoadipyl-7-ACA is recognized as a substrate by glutaryl acylase (GAC) and hydrolyzed as long as glutaric acid is absent from the reaction medium (because it is able to inhibit the hydrolysis). The low stability of ,-ketoadipyl-7-ACA justifies the use of a single reactor, in which glutaryl acylase is already present when this substrate is generated. Thus, the whole process may (and must) be performed in a single step, and in the absence of hydrogen peroxide that could affect the stabilities of the involved enzymes. [source] Dermatan sulfate exerts an enhanced growth factor response on skeletal muscle satellite cell proliferation and migrationJOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2004Joan Villena Skeletal muscle regeneration is a complex process in which many agents are involved. When skeletal muscle suffers an injury, quiescent resident myoblasts called satellite cells are activated to proliferate, migrate, and finally differentiate. This whole process occurs in the presence of growth factors, the extracellular matrix (ECM), and infiltrating macrophages. We have shown previously that different proteoglycans, either present at the plasma membrane or the ECM, are involved in the differentiation process by regulating growth factor activity. In this article, we evaluated the role of glycosaminoglycans (GAGs) in myoblast proliferation and migration, using C2C12, a satellite cell-derived cell line. A synergic stimulatory effect on myoblast proliferation was observed with hepatocyte growth factor (HGF) and fibroblast growth factor type 2 (FGF-2), which was dependent on cell sulfation. The GAG dermatan sulfate (DS) enhanced HGF/FGF-2-dependent proliferation at 1,10 ng/ml. However, decorin, a proteoglycan containing DS, was unable to reproduce this enhanced proliferative effect. On the other hand, HGF strongly increased myoblast migration. The HGF-dependent migratory process required the presence of sulfated proteoglycans/GAGs present on the myoblast surface, as inhibition of both cell sulfation, and heparitinase (Hase) and chondroitinase ABC (Chabc) treatment of myoblasts, resulted in a very strong inhibition of cell migration. Among the GAGs analyzed, DS most increased HGF-dependent myoblast migration. Taken together, these findings showed that DS is an enhancer of growth factor-dependent proliferation and migration, two critical processes involved in skeletal muscle formation. J. Cell. Physiol. 198: 169,178, 2004© 2003 Wiley-Liss, Inc. [source] Breeding biology of ostriches (Struthio camelus) in the Serengeti ecosystem, TanzaniaAFRICAN JOURNAL OF ECOLOGY, Issue 3 2009Flora J. Magige Abstract Ostrich breeding behaviour in the Serengeti ecosystem, Tanzania was investigated for differences in laying dates between low altitude western area (WA) and high altitude eastern area (EA) populations. Ostriches in WA laid eggs significantly earlier than in EA. The differences could be attributed to topography and rainfall pattern. Reliable rains in lower altitudes ensure availability of food that in turn influences the whole process of the reproductive cycle. Clutches were contributed by several females with a nest having up to 38 eggs. We also compared the frequency of observation of predators, ostriches, nests, ,singletons' (single eggs laid randomly) and broods between the two areas. There was no significant difference between WA and EA in 1) ostrich/nest ratio, indicating similar breeding densities; 2) ostrich/predator and predator/nest ratios, indicating that predation pressure was equally high; 3) nest/singleton and predator/singleton ratios, indicating that loss of nests did not vary between areas. However, there were significantly more predators, nests and ostriches compared to broods in EA than in WA, indicating a significantly lower reproductive success in EA. Using metapopulation terminology, ostriches in EA could be regarded as a ,sink' population and those in WA as a ,source' population, but investigations over longer time-periods are needed to further resolve if this is the case. Résumé Le comportement reproducteur des autruches dans l'écosystème du Serengeti, en Tanzanie, a étéétudié pour voir les différences dans les dates de pontes entre les populations de la zone occidentale (WA) à basse altitude et de la zone orientale (EA) à plus haute altitude. Les autruches de la WA pondent significativement plus tôt que celles de l'EA. Les différences peuvent être attribuées à la topographie et au régime de la pluviosité. Les pluies fiables à plus basse altitude garantissent la disponibilité de la nourriture, ce qui influence dès lors tout le processus du cycle reproducteur. Des couvées réunissaient les ,ufs de plusieurs femelles , un nid a eu jusqu'à 38 ,ufs. Nous avons aussi comparé la fréquence d'observations de prédateurs, d'autruches, de nids, de «ingletons» (des ,ufs solitaires pondus au hasard) et de nichées entre les deux zones. Il n'y a pas de différence significative entre WA et EA pour 1) le ratio autruches/nids, ce qui indique des densités de reproduction similaires; 2) le ratio autruches/prédateurs et le ratio prédateurs/nids, ce qui indique que la pression de la prédation est aussi haute des deux côtés; et 3) le ratio nids/singletons et le ratio prédateurs/singletons, ce qui indique que la perte des nids ne variait pas entre les zones. Cependant, il y avait significativement plus de prédateurs, de nids et d'autruches par rapport aux nichées dans l'EA que dans la WA, ce qui indique une réussite de la reproduction significativement plus faible dans la EA. En utilisant la terminologie de la métapopulation, les autruches de la EA peuvent être considérées comme une population «puits» et celles de la WA comme une population «source», mais il faudrait faire des recherches de plus longue durée pour montrer si c'est bien le cas. [source] Molecular dynamics simulations of the detoxification of paraoxon catalyzed by phosphotriesteraseJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 15 2009Xin Zhang Abstract Combined QM(PM3)/MM molecular dynamics simulations together with QM(DFT)/MM optimizations for key configurations have been performed to elucidate the enzymatic catalysis mechanism on the detoxification of paraoxon by phosphotriesterase (PTE). In the simulations, the PM3 parameters for the phosphorous atom were reoptimized. The equilibrated configuration of the enzyme/substrate complex showed that paraoxon can strongly bind to the more solvent-exposed metal ion Zn,, but the free energy profile along the binding path demonstrated that the binding is thermodynamically unfavorable. This explains why the crystal structures of PTE with substrate analogues often exhibit long distances between the phosphoral oxygen and Zn,. The subsequent SN2 reaction plays the key role in the whole process, but controversies exist over the identity of the nucleophilic species, which could be either a hydroxide ion terminally coordinated to Zn, or the ,-hydroxo bridge between the ,- and ,-metals. Our simulations supported the latter and showed that the rate-limiting step is the distortion of the bound paraoxon to approach the bridging hydroxide. After this preparation step, the bridging hydroxide ion attacks the phosphorous center and replaces the diethyl phosphate with a low barrier. Thus, a plausible way to engineer PTE with enhanced catalytic activity is to stabilize the deformed paraoxon. Conformational analyses indicate that Trp131 is the closest residue to the phosphoryl oxygen, and mutations to Arg or Gln or even Lys, which can shorten the hydrogen bond distance with the phosphoryl oxygen, could potentially lead to a mutant with enhanced activity for the detoxification of organophosphates. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Temporally-resolved inkjet drop impaction on surfacesAICHE JOURNAL, Issue 10 2007Hongming Dong Abstract Impaction on smooth solid substrates of drops formed by the drop-on-demand (DOD) method was investigated over a wide range of impaction speeds (U0 = 2.21,12.2 m/s), surface contact angles (, = 6,107°), and drop diameters (D0 = 40.8,50.5 ,m). The experimental results were compared with several existing equations for predicting maximum spreading. The dimensionless time to reach maximum spreading ratio, scaled by D0/U0, ranged from 0.6 to 2.99, depending on Weber number and contact angle. Micron and millimeter drop impactions were compared, and the results indicate that scaling based on three dimensionless numbers (We, Re or Oh, and cos ,) is valid, but spreading ratios of millimeter drops are usually slightly larger during the whole process. The difference is ascribed mainly to the effect of gravity. © 2007 American Institute of Chemical Engineers AIChE J, 2007 [source] Values and evaluation in health careJOURNAL OF NURSING MANAGEMENT, Issue 3 2001A. Sarvimäki PHD RN The purpose of this paper is to broaden the view of evaluation in health care by ,problemizing' the concepts of quality and evaluation and relating them to a more general discussion of values. The discussion of the concept of quality shows that the concept of quality is often vague or contradictory and that the relationship between quality and costs is problematic. The discussion is broadened by studying quality and evaluation from the viewpoint of four categories of values: scientific values, aesthetic values, ethical values and economic values. The authors also show that values, in addition to constituting the basis for evaluation, actually guide the whole process of care. Values are explicit and implicit elements of the care culture and the individual's action system. The authors conclude that the four value categories could be used to study which values actually guide the care process in real situations. [source] Dryout phenomena in a three-phase fixed-bed reactorAICHE JOURNAL, Issue 1 2003Zhen-Min Cheng Understanding the mechanism of liquid-phase evaporation in a three-phase fixed-bed reactor is of practical importance, because the reaction heat is usually 7,10 times the vaporization heat of the liquid components. Evaporation, especially the liquid dryout, can largely influence the reactor performance and even safety. To predict the vanishing condition of the liquid phase, Raoult's law was applied as a preliminary approach, with the liquid vanishing temperature defined based on a liquid flow rate of zero. While providing correct trends, Raoult's law exhibits some limitation in explaining the temperature profile in the reactor. To comprehensively understand the whole process of liquid evaporation, a set of experiments on inlet temperature, catalyst activity, liquid flow rate, gas flow rate, and operation pressure were carried out. A liquid-region length-predicting equation is suggested based on these experiments and the principle of heat balance. [source] Spin: from tactic to tabloidJOURNAL OF PUBLIC AFFAIRS, Issue 1 2006Leighton Andrews Over the last fifteen years, the word Spin has come to define both the process of political communication, and the practice of public relations itself. The history of the term requires some examination. Arguably, until around 1992, Spin did not have such a widespread meaning,it was simply one tactic in an election campaigner's armoury. Now it seems to embrace the whole process of communication, not only between election campaigners and the media, but also between a Government and its people, or between a public relations professional in any field, and his or her target publics. The development of Spin as a word has gone through a number of stages which will be addressed in the course of this paper. It now has widespread popular usage, which has arisen through two principal processes: The increasing celebrity status of the spin-doctor role: and the usefulness of the word to tabloid sub-editors. By 1997, when New Labour came into Government, the discourse of spin was firmly established. Copyright © 2006 John Wiley & Sons, Ltd. [source] An MDA-based approach for database re-engineeringJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 6 2007Macario Polo Abstract This article presents the technical and functional descriptions of a tool specifically designed for database re-engineering. As is well known, re-engineering is the process of (1) applying reverse engineering to a software product to obtain higher-level specifications and (2) using these specifications as the starting point for the development of a new version of the system. Thus, the complete process can be seen as a sequence of transformation functions that operate on the different sets involved in the whole process. The starting point of the re-engineering process is the physical schema of the database which is translated into a vendor-independent metamodel (the logical schema) and then translated into a class diagram representing a possible conceptual schema of the database. This diagram is then taken as the starting point for the code generation process, which produces an executable application for four possible different platforms. Copyright © 2007 John Wiley & Sons, Ltd. [source] Compositional and degradative changes during the manufacture of dry-cured ,lacón'JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2003José M Lorenzo Abstract The gross and mineral composition, the main physicochemical parameters, the protein extractability and the proteolytic (nitrogen fractions and free amino acids) and lipolytic (acidity index and free fatty acids) changes were studied throughout the manufacturing process of five batches of dry-cured ,lacón', a traditional Spanish meat product made from the fore-ham of the pig following a similar technological process to that of dry-cured ham. The main compositional characteristics of this product are the high NaCl content and the low moisture content at the end of the curing process. The pH remained fairly stable (around 6) throughout the whole process and a fall in aw was observed, reaching very low (0.767 ± 0.052) final average values. It was noted that 76% of the sarcoplasmic and 83% of the myofibrillar proteins became insoluble during the manufacturing process. The values of the different nitrogen fractions increased in a significant manner during manufacture, reaching low final values that indicate that ,lacón' undergoes a low level of proteolysis in comparison with other products manufactured by similar technologies. The high NaCl content and the intense dehydration suffered during the manufacturing process appear to be the principal causes of this reduced protein degradation. In accordance with the limited increase in the ,-amino acidic nitrogen during ripening, the total free amino acid content increased slightly but significantly from average values of 4371 mg kg,1 dry matter in fresh pieces to average values of 13 020 mg kg,1 dry matter in pieces at the end of the ripening process. The profile of free amino acids in the final product was similar to that observed by other authors in dry-cured ham. The acidity of the fat increased by a factor of five. The final average values (49.9 g oleic acid kg,1) were lower than those determined in dry-cured ham, which indicates that ,lacón' undergoes less lipolysis during the ripening process than dry-cured ham. C18 : 1, C18 : 2 and C16 were the most intensively released fatty acids during curing. The profile of free fatty acids in the end product was in agreement with that observed by other authors in dry-cured ham. Copyright © 2003 Society of Chemical Industry [source] Measurement of electrical conductivity, differential scanning calorimetry and viscosity of starch and flour suspensions during gelatinisation processJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2001Saiwarun Chaiwanichsiri Abstract Electrical conductivity measurements were applied to analyse the gelatinisation process of 12 starch or flour suspensions. The electrical conductivity of starch suspensions was found to increase upon gelatinisation because of the release of ions from starch granules. The initiation temperature of ion release, Ti, correlated well with the onset temperature in the DSC thermogram (R,=,0.868), while the completion temperature of ion release, Tf, correlated with the temperature at the start of viscosity increase (R,=,0.865). Thus Ti and Tf corresponded to the beginning and ending temperatures of gelatinisation respectively. The electrical conductivity measurement will be used as an on-line technique to monitor the whole process of starch gelatinisation. © 2001 Society of Chemical Industry [source] Direct Observation of , -Chloro- p -quinodimethane as the Real Monomer in the Gilch Polymerization Leading to Poly(p -phenylene vinylene)sMACROMOLECULAR RAPID COMMUNICATIONS, Issue 2 2007Jens Wiesecke Abstract It is the general consensus that in Gilch polymerizations the 1,4-bis(chloromethylene)benzene starting material first changes into p -quinodimethane intermediates which then act as the real monomers. However, direct observation of these intermediates has not been possible so far. This is because usually the p -quinodimethane auto-initiates its rapid radical polymerization instantaneously, keeping its concentration extremely low throughout the whole process. Here it is shown that, when the reaction is carried out at very low temperatures, the formation of p -quinodimethane still proceeds but chain growth is suppressed. Hence, the concentration of the active monomer reaches a level sufficient for NMR analysis. [source] Synergistic effect of chloride and sulfite ions on the atmospheric corrosion of bronzeMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 5 2006X. Cao Abstract The effect of chloride along with sulfite ions on the atmospheric corrosion of bronze was investigated by using periodic wet-dry tests, surface tension tests and electrochemical impedance measurements. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the corrosion products. Both the electrochemical impedance measurements and surface tension tests agreed well with the results of weight loss measurements. Synergistic effect of chloride and sulfite ions was observed during the whole process. In addition, we found that the attack of anions on the metal at the initial corrosion stage showed good agreement with their surface activity. However, as the corrosion proceeded, the interaction among the corrosion products induced by chloride and HSO3, accelerated the corrosion process. A scheme was given to explain the whole corrosion process. [source] SIMM: An integrated forecasting system for the Mediterranean areaMETEOROLOGICAL APPLICATIONS, Issue 4 2007Antonio Speranza Abstract Many ,high-impact' meteorological, marine and hydrological events in the Mediterranean area are characterized by horizontal spatial scales of the order of 10,100 km. Such events are, sometimes, driven by complex dynamical processes involving planetary scale atmospheric flows. Several international programs (ALPEX, POEM, MAP, PYREX, MEDEX) have improved the understanding of some of these processes. However, because of the Mediterranean's geomorphological structure, characterized by mountain chains (e.g. the Alps), semi-enclosed sea basins and small river catchments, many problems remain. It is clear that such problems have to be faced in the context of analysis-prediction systems bridging the gap between global and local scales of motion. These systems should allow for an adequate representation of key dynamical processes at all the relevant scales of motion. The Hydro-Meteorological-Marine System (,Sistema Idro-Meteo-Mare', SIMM) is a first step in developing an integrated system, adequately covering all scales of motion from global to local. A short description of the system is presented, highlighting scientific concepts behind design choices. A summary of the results of verification tests is also illustrated, together with a general evaluation of the whole process in planning, developing and running SIMM in order to assist future updates of the system, currently under development. Copyright © 2007 Royal Meteorological Society [source] Cytokine-regulated accumulation of eosinophils in inflammatory diseaseALLERGY, Issue 8 2004M. Lampinen The role of cytokines in the accumulation of eosinophil granulocytes in inflamed tissue has been studied extensively during recent years, and these molecules have been found to participate throughout the whole process of eosinophil recruitment. Haematopoietic cytokines such as IL-3, IL-5 and GM-CSF stimulate the proliferation and differentiation of eosinophils in the bone marrow, and the release of mature eosinophils from the bone marrow into the blood is probably promoted by IL-5. Priming of eosinophils in the blood following, for example, allergen challenge is performed mainly by IL-3, IL-5 and GM-CSF. An important step in the extravasation of eosinophils is their adhesion to the vascular endothelium. Adhesion molecules are upregulated by, e.g. IL-1, IL-4, TNF- , and IFN- , and the same cytokines may also increase the affinity of adhesion molecules both on eosinophils and endothelial cells. Finally, a number of cytokines have been shown to act as eosinophil chemotactic factors, attracting the cells to the inflammatory focus in the tissue. Some of the most important eosinophil chemoattractant cytokines are IL-5, IL-8, RANTES, eotaxin, eotaxin-2, eotaxin-3, MCP-3, MCP-4 and TNF- ,. Th2 cells, mast cells and epithelial cells are important sources of proinflammatory cytokines, but in recent years, the eosinophils have also been recognized as cytokine-producing and thereby immunoregulatory cells. The aim of this paper is to review the role of cytokines in the process of eosinophil recruitment in asthma, allergy and ulcerative colitis. [source] The Future of Gaseous Fuels in Hong KongOPEC ENERGY REVIEW, Issue 1 2001Larry Chuen-ho Chow There are three types of gaseous fuel in Hong Kong. Natural gas, exclusively used for power generation and imported under a 20-year contract, accounted for 16 per cent of total primary energy requirements in 1998. Towngas, manufactured from naphtha, and liquefied petroleum gas are the two other kinds, accounting for about 9.5 per cent of the final energy requirement in recent years. The first part of this paper analyses the competition between these two gaseous fuels since 1984, elucidating in detail how towngas came to dominate the gaseous fuel market. The government of the Hong Kong Special Administrative Region would like to boost the use of natural gas in Hong Kong, on account of its environmental benefits and cost competitiveness. It is considering the possibility of using natural gas to replace the other two gaseous fuels and adopting the common carrier system, in order to spur competition in the gaseous fuel market. The second part of the study evaluates the feasibility of converting to natural gas and opening up the pipeline system, putting forth a rough schedule for the whole process. [source] Pleural plaques in dentists from occupational asbestos exposure: A report of three casesAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 12 2009FCCP, L. Sichletidis MD Abstract Background White asbestos (chrysotile) has been used in dentistry since 1930 when it was introduced as a lining material for casting rings. Methods All three patients presented with pleural plaques on chest X-rays as well as on CT-scans. They were working as dentists for 35,45 years. Under the instructions of the first dentist we represented precisely the whole process of manipulating a kind of paper that contained asbestos. In order to measure asbestos fibers concentration we used the membrane filter method and phase contrast optical microscopy. Dry asbestos sheets were scanned with x-ray diffraction and electron microscope. Results Analysis of the filter demonstrated 0.008 fibers/cm3 during the sampling period. X-ray diffraction analysis revealed that the material consisted of chrysotile exclusively. Electron microscope pictures confirmed the presence of chrysotile. Conclusion Everyday occupational exposure for many years even to low asbestos levels, under poor ventilation conditions in a closed space, could cause pleural lesions. Am. J. Ind. Med. 52:926,930, 2009. © 2009 Wiley-Liss, Inc. [source] An optimization procedure for the pultrusion process based on a finite element formulationPOLYMER COMPOSITES, Issue 3 2002R. M. L. Coelho Composite materials are manufactured by different processes. In all, the process variables have to be analyzed in order to obtain a part with uniform mechanical properties. In the pultrusion process, two variables are the most important: the pulling speed of resin-impregnated fibers and the temperature profile (boundary condition) imposed on the mold wall. Mathematical modeling of this process results in partial differential equations that are solved here by a detailed procedure based on the Galerkin weighted residual finite element method. The combination of the Picard and Newton-Raphson methods with an analytical Jacobian calculation proves to be robust, and a mesh adaptation procedure is presented in order to avoid integration errors during the process optimization. The two earlier-mentioned variables are optimized by the Simulated Annealing method with some constraints, such as a minimum degree of cure at the end of the process, and the resin degradation (the part temperature cannot be higher than the resin degradation temperature at any time during the whole process). Herein, the proposed objective function is an economic criterion instead of the pulling speed of resin-impregnated fibers, used in the majority of papers. [source] Purification of metallurgical-grade silicon up to solar gradePROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 3 2001N. Yuge An estimate has been made of the feasibility of a metallurgical purification process, the NEDO (New Energy and Industrial Technology Development Organization) melt-purification process, for manufacturing solar-grade silicon from metallurgical-grade silicon. Equipment has been developed to pilot manufacturing plant scale. The system comprises an electron-beam furnace for phosphorus removal and a plasma furnace for boron removal. Each furnace has a mold for directional solidification to remove metallic impurities. The concentration of each impurity in the silicon ingot purified through the whole process satisfied the solar-grade level. The Solar-grade silicon produced showed p -type polarity and resistivity within the range 0·5,1·5,,,cm. Copyright © 2001 John Wiley & Sons, Ltd. [source] OVNIp: An open source application facilitating the interpretation, the validation and the edition of proteomics data generated by MS analyses and de novo sequencingPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 9 2010Dominique Tessier Abstract Several academic software are available to help the validation and reporting of proteomics data generated by MS analyses. However, to our knowledge, none of them have been conceived to meet the particular needs generated by the study of organisms whose genomes are not sequenced. In that context, we have developed OVNIp, an open-source application which facilitates the whole process of proteomics results interpretation. One of its unique attributes is its capacity to compile multiple results (from several search engines and/or several databank searches) with a resolution of conflicting interpretations. Moreover, OVNIp enables automated exploitation of de novo sequences generated from unassigned MS/MS spectra leading to higher sequence coverage and enhancing confidence in the identified proteins. The exploitation of these additional spectra might also identify novel proteins through a MS-BLAST search, which can be easily ran from the OVNIp interface. Beyond this primary scope, OVNIp can also benefit to users who look for a simple standalone application to both visualize and confirm MS/MS result interpretations through a simple graphical interface and generate reports according to user-defined forms which may integrate the prerequisites for publication. Sources, documentation and a stable release for Windows are available at http://wwwappli.nantes.inra.fr:8180/OVNIp. [source] An optimum method designed for 2-D DIGE analysis of human arterial intima and media layers isolated by laser microdissectionPROTEOMICS - CLINICAL APPLICATIONS, Issue 10 2009Fernando de la Cuesta Abstract The formation and progression of atherosclerotic lesions involve complex mechanisms which are still not fully understood. A variety of cell types from the distinct arterial layers are implicated in the whole process from lipid accumulation within the vascular wall to plaque development and final rupture. In the present work, we employ the combination of laser microdissection and pressure catapulting and 2-D DIGE saturation labeling to investigate the human intima and media sub-proteomes isolated from atherosclerotic (coronary and aorta) or non-atherosclerotic vessels (preatherosclerotic coronary arteries). Laser microdissection and pressure catapulting allows the specific isolation of regions of interest. In turn, DIGE saturation labeling overcomes the limitation of extensive microdissection times to recover the protein amount required to perform comparative 2-DE, particularly when dealing with tissue regions rich in myofilament proteins, which result in low protein recovery. The compatibility and optimum performance of both techniques were investigated in detail, paying special attention to tissue staining and protein solubilization. Since scarce amount of protein obtained from microdissected tissue made it impossible to directly perform protein identification from 2-DE spots by MS, we performed in-solution digestion followed by LC-MS/MS analysis of total protein extracts from intima and media in order to get an overall picture of protein composition. Proteins so identified confirm the nature of the isolated regions. Finally, similar spot resolution on 2-D DIGE gels was obtained for the different human artery types (coronary, aorta) and studied layers (intima, media), setting the basis for future clinical comparative studies. [source] A semiquantitative analysis of the dynamics of a Goldman-type vaporiserANAESTHESIA, Issue 6 2000D. A. Young When a turbulent flow of a carrier gas is passed over a liquid anaesthetic agent contained in a vaporiser of Goldman design, evaporation from the cooled surface leads rapidly to a succession of fluid instabilities which set in at characteristic critical conditions. An initially quiescent boundary layer at the surface is sequentially replaced by a thin layer of toroidal (Bénard,Marangoni) convection cells which are driven by surface tension gradients. These are then augmented by Rayleigh,Bénard convection driven by gravity, the whole process terminating in intermittent columnar plunging of cold fluid from a chaotic surface layer of pulsating thickness to the base of the liquid pool. Residual striations from these plunging columns persist throughout the bulk of the liquid so long as evaporation continues. The ultimate state is then one in which turbulence occurs throughout both liquid and vapour phases. In this paper, a semiquantitative analysis of the system dynamics is given with supportive experimental evidence where possible. [source] CORRUPTION IN PUBLIC CONTRACTING AUCTIONS: THE ROLE OF TRANSPARENCY IN BIDDING PROCESSESANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 4 2006Frédéric Boehm ABSTRACT,:,The paper discusses corruption in public auctions and the role of transparency as a tool to prevent it. First, we analyse where corruption occurs, emphasizing the importance of considering the whole process, from deciding whether to contract-out to implementing the contract. We then analyse the effects of corruption on public auctions and argue that corruption undermines their stated aims. Second, we discuss the ways transparency can mitigate corruption and possible trade-offs regarding competition and efficiency. As an instrument, we focus on the Integrity Pact, a tool developed by Transparency International, and analyse cases in Argentina (school supplies) and Colombia (telecommunications), where transparency helped to prevent corruption and collusion and, furthermore, was able to enhance competition. We conclude with some policy implications. [source] Heroin-Administered Mice Involved in Oxidative Stress and Exogenous Antioxidant-Alleviated Withdrawal SyndromeBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 2 2006Bo Xu It is well known that an increase in DA oxidative metabolism leads to increased reactive oxygen species (ROS) formation, and thus, ROS have been frequently associated with neuronal cell death due to damage to carbohydrates, amino acids, phospholipids, and nucleic acids. This study investigated whether there are oxidative stress and effects of exogenous antioxidants in heroin-administered mice. The heroin-dependent mice model was made via intraperitoneal injection. Oxidative damage of DNA, protein, and lipid was measured by analysis of single cell electrophoresis, the 2,4-dinitrophenylhydrazine method, and thiobarbituric acid method respectively. The activities of antioxidative enzymes and total antioxidant capacity were assayed by spectrophotometry. After administration with heroin, the mice not only showed decrease of total antioxidant capacity in serum and antioxidant enzymes such as superoxide dismutase, catalase, and glutathione (GSH) peroxidase in brain, but also exhibited the oxidative damages of DNA, protein and lipid. On the other hand, exogenous antioxidants could restrain the oxidative stress, even alleviate withdrawal syndrome in heroin-administered mice. Our results also imply a possibility that ROS may participate in the whole process of dependence and withdrawal of heroin. Therefore, strategies of blocking oxidative stress may be useful in the development of therapy for opiate abuse. [source] Numerical Study on Bubble Formation of a Gas-Liquid Flow in a T-Junction MicrochannelCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 12 2009L. Dai Abstract Bubble emergence in a gas-liquid flow in a T-junction microchannel of 100,,m diameter, operated under a squeezing regime, was simulated with the computational fluid dynamics method. In general, bubble formation in channels includes three stages: expansion, collapse and pinching off. After analyzing and comparing quantitatively the three forces of pressure, surface tension and shear stress acting on the gas thread in the whole process, their effects in the different stages were identified. The collapse stage was the most important for bubble formation and was investigated in detail. It was found that the collapse process was mostly influenced by the liquid superficial velocity, and the rate and time of collapse can be correlated with empirical equations including the liquid superficial velocity, the capillary number and the Reynolds number. [source] | ||||||||||||||||||||||||||||