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Similar Behavior (similar + behavior)
Selected AbstractsSemi-Automatic Time-Series Transfer Functions via Temporal Clustering and SequencingCOMPUTER GRAPHICS FORUM, Issue 3 2009Jonathan Woodring Abstract When creating transfer functions for time-varying data, it is not clear what range of values to use for classification, as data value ranges and distributions change over time. In order to generate time-varying transfer functions, we search the data for classes that have similar behavior over time, assuming that data points that behave similarly belong to the same feature. We utilize a method we call temporal clustering and sequencing to find dynamic features in value space and create a corresponding transfer function. First, clustering finds groups of data points that have the same value space activity over time. Then, sequencing derives a progression of clusters over time, creating chains that follow value distribution changes. Finally, the cluster sequences are used to create transfer functions, as sequences describe the value range distributions over time in a data set. [source] Voltammetric Studies of Parallel Electrode Processes Under Low Ionic Strength Conditions.ELECTROANALYSIS, Issue 7 2006Influence of Convection Abstract It is known that either a very strong enhancement or an almost complete depression of the height of one of two waves can be obtained when two analytes (one appropriately charged and one uncharged) are present in a quiet solution containing no supporting electrolyte. In this paper we examine whether these effects can be extended for solutions with forced convection. Three two-analyte mixtures were examined voltammetrically under conditions of no added supporting electrolyte and added convection. The first mixture (1,1,-ferrocenedimethanol and ferrocenesulfonate anion) changes its total charge from ,1 to +1 after electrooxidation of both components. Under all applied conditions, the introduction of convection caused an increase of both waves without changing the wave height ratio. A similar behavior was observed for the mixture of ferrocene and 1,1,-ferrocenedimethanol. For this system the total charge changes from 0 to +2. A substantial influence of convection on the ratio of two waves was found for the third mixture: ferrocene and ferrocenylmethyltrimethylammonium cation (total charge changes from +1 to +3). For this system the convection strongly depressed the migrational effects. The obtained experimental results were verified with simulations using software MIOTRAS. This software is capable of modeling diffusion, migration, convection and following homogenous reactions. The agreement between experiment and simulations was fairly good. [source] Surface temperature of decomposing construction materials studied by laser-induced phosphorescenceFIRE AND MATERIALS, Issue 1 2005Alaa Omrane Abstract Measurements of surface temperature and mass loss of decomposing construction materials during rapid pyrolysis are presented. Experiments have been performed with samples of low-density fiberboard, medium-density fiberboard, particleboard and poly(methyl methacrylate) in a single particle reactor at temperatures between 300° and 600°C. Ultraviolet laser light was used to excite micrometer-sized thermographic phosphor particles that were deposited on the investigated materials, and the temperature was obtained from temporally resolved measurements of the laser-induced emission. The wood-based materials show a similar behavior, with small differences being attributed to differences in material properties. The surface temperature rapidly increases to about 400°C when a particle is introduced to the hot reactor. The initial phase is followed by rapid decomposition during which the surface temperature is 380°,540°C. The heating rate is slowed down during the rapid pyrolysis, and again increases as the remaining char is heated to the reactor temperature. The poly (methyl methacrylate), however, melts and at high temperatures can be characterized as a liquid with a boiling point of about 400°C. Thermographic phosphors are concluded to be suitable for high precision remote measurements of the surface temperature of decomposing construction materials, and possibilities for further studies and developments of the technique are discussed. Copyright © 2004 John Wiley & Sons, Ltd. [source] The degradation of cell cycle regulators by SKP2/CKS1 ubiquitin ligase is genetically controlled in rodent liver cancer and contributes to determine the susceptibility to the diseaseINTERNATIONAL JOURNAL OF CANCER, Issue 5 2010Diego F. Calvisi Abstract Previous work showed a genetic control of cell cycle deregulation during hepatocarcinogenesis. We now evaluated in preneoplastic lesions, dysplastic nodules and hepatocellular carcinoma (HCC), chemically induced in genetically susceptible F344 and resistant Brown Norway (BN) rats, the role of cell cycle regulating proteins in the determination of a phenotype susceptible to HCC development. p21WAF1, p27KIP1, p57KIP2 and p130 mRNA levels increased in fast growing lesions of F344 rats. Lower/no increases occurred in slowly growing lesions of BN rats. A similar behavior of RassF1A mRNA was previously found in the 2 rat strains. However, p21WAF1, p27KIP1, p57KIP, p130 and RassF1A proteins exhibited no change/low increase in the lesions of F344 rats and consistent rise in dysplastic nodules and HCC of BN rats. Increase in Cks1-Skp2 ligase and ubiquitination of cell cycle regulators occurred in F344 but not in BN rat lesions, indicating that posttranslational modifications of cell cycle regulators are under genetic control and contribute to determine a phenotype susceptible to HCC. Moreover, proliferation index of 60 human HCCs was inversely correlated with protein levels but not with mRNA levels of P21WAF1, P27KIP1, P57KIP2 and P130, indicating a control of human HCC proliferation by posttranslational modifications of cell cycle regulators. [source] Effect of count duration on abundance estimates of Black-capped VireosJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2009David A. Cimprich ABSTRACT Distance sampling applied to point count surveys (point transects) has become a common method for estimating the absolute abundance of birds. When conducting point transects, detections of focal species are typically recorded during a fixed time interval. However, count duration has varied among studies and the effect of such variation on the resulting abundance estimates is unclear. My objective was to examine the effect of count duration on abundance estimates of male Black-capped Vireos (Vireo atricapilla). The abundance of these vireos in a 349-ha area in central Texas was estimated using 3-, 5-, and 6-min point transects and results were then compared to actual number present as determined by banding and territory mapping. The 3-min counts provided an estimate that was 26% greater than the actual number of male Vireos present (N= 201), but this number was within the corresponding 95% confidence interval (N= 157,413). Confidence intervals for the 5- and 6-min counts did not include the actual number of vireos present. The shortest count duration may have provided the most accurate abundance estimate because male Black-capped Vireos are typically active, sing intermittently, and sometimes move tens of meters between songs. Thus, shorter-duration counts may also yield the most accurate abundance estimates for other species that exhibit similar behavior. However, because behavior varies among species, I recommend that investigators collect preliminary data to establish an appropriate count duration when accurate estimates of absolute, rather than relative, abundance are important. RESUMEN El muestreo a distancia aplicado a conteos de punto (transectos de punto) se ha convertido en un método común para estimar la abundancia absoluta de aves. Cuando se conducen conteos de punto, la detección de especies focales, típicamente, se lleva a cabo durante un periodo de tiempo definido. Sin embargo, la duración de tiempo del conteo, varía en diferentes estudios y el efecto de dicha variación, en los estimados de abundancia, no está definido. Mi objetivo fue examinar el efecto del periodo de tiempo usado en los conteos utilizando como objeto de estudio a Vireo atricapilla. La abundancia de dichas aves en 349 ha en la parte central de Texas, fue estimada utilizando periodos de 3, 5 y 6 minutos en cada punto del transecto. Los resultados fueron comparados a números obtenidos con recobro de animales anillados y mapas de territorios. Los conteos de 3 minutos dieron como resultado un 26% más alto que el número de machos presentes en la localidad (N= 201). Pero dichos resultados estuvieron dentro del intérvalo de confiabilidad de 95% (N= 157,413). Intérvalos de 5 y 6 minutos no estimaron adecuadamente el número de vireos presentes. El conteo más corto (3 minutos) suministró los números más exactos, aparentemente porque el ave estudiada, típicamente está activa, canta de forma intermitente y en ocasiones se mueve de lugar (decenas de metros) entre canciones. Por lo tanto los conteos más cortos deben de proveer los estimados de abundancia más precisos para otras especies de aves con hábitos similares. Sin embargo, dado el caso de que la conducta entre especies varía, recomendamos a otros investigadores, que tomen datos preliminares para establecer la duración más apropiada de conteos, cuando se necesiten estimados de absoluta exactitud, en vez de estimados relativos de abundancia. [source] Protein Denaturation and Structural Damage During High-Pressure-Shift Freezing of Porcine and Bovine MuscleJOURNAL OF FOOD SCIENCE, Issue 6 2000F. Fernández-Martín ABSTRACT: Pork and beef muscles were subjected to 200 MPa and ,20 °C with or without water freezing. Both tissues responded to the treatment with similar behavior. Protein denaturation was greater when freezing occurred. Pressure-induced cold denaturation was complete for actin and very considerable for myosin and other muscle proteins. Connective proteins remained practically unaltered by pressurization and/or freezing. Structural changes in the muscle at sarcomere levels caused by pressurization were more severe when freezing occurred. Color, drip loss, and textural properties on the pressurized samples also revealed an additional deleterious influence of freezing. Pressurization alone and pressure-shift freezing resulted unsuitable for muscle preservation. [source] Mechanical Properties and Dimensional Effects of ZnO- and SnO2 -Based VaristorsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2008Miguel Angel Ramírez A comparison between traditional ZnO-(modified Matsuoka system, [ZnO]) and SnO2 -based varistors (98.9%SnO2+1%CoO+0.05%Nb2O5+0.05%Cr2O3, [SCNCr]) regarding their mechanical properties, finite element (FE) modeling, and macroscopic response with current pulse is presented in this work. The experimental values of the elastic (static and dynamic) modulus and bending strength are given. Both the static and the dynamic modulus were two times higher for SnO2 (,200 GPa) with respect to ZnO (,100 GPa). A similar behavior was found for the bending strength, confirming the superior mechanical properties of SCNCr associated with a homogeneous microstructure. The finite element analyses yielded the most appropriate thickness/diameter aspect ratio (H/D), while thermomechanical stress is minimized. The values of (H/D) were lower for the SCNCr in comparison with the ZnO-based varistors, allowing the production of smaller pieces that can resist the same thermomechanical stress. Finally, preliminary analyses of the macroscopic failures for samples treated with degradation pulses of 8/20-,s type allowed to confirm the absence of failures due to cracking and/or puncture in the SCNCr. The absence of these failures originates from the good thermomechanical properties. [source] EVAPOTRANSPIRATION DYNAMICS AT AN ECOHYDROLOGICAL RESTORATION SITE: AN ENERGY BALANCE AND REMOTE SENSING APPROACH,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2006Jason W. Oberg ABSTRACT: Little work is reported where spatial methods are employed to monitor evapotranspiration (ET) changes as a result of vegetation and wetland restoration. A remote sensing approach with the Surface Energy Balance Algorithm for Land (SEBAL) for estimating ET at The Nature Conservancy's Glacial Ridge prairie-wetland restoration site in northwestern Minnesota is presented. The calibrated 24-hour ET from SEBAL was estimated with an average error of prediction of ,4.3 percent. Monthly, interseasonal, and seasonal ET for the period of June to September (2000 to 2003) from three adjacent land-uses: a hydrologic control preserved wetland; a treated or restored site; and a nontreated or impacted wetland, were used in the study. Results from comparing ET behavior to the preserve suggest restoration efforts have affected monthly and seasonal ET within the treated site. Spatial average standard deviations of the seasonal ET within the preserve, treated, and nontreated sites give 47.3, 75.7, and 109.9 mm, respectively, suggesting hydrologic stabilization within the treated site. Monthly and interseasonal comparisons show similar behavior to that of the seasonal data, where monthly correlations suggest increasing agreement within the treated site, approaching those within the preserve. [source] Magneto-dielectric properties of the Y3Fe5O12 and Gd3Fe5O12 dielectric ferrite resonator antennasMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2008P. B. A. Fechine Abstract The main objective of this work was to study the magnetic and dielectric properties of Y3Fe5O12 and Gd3Fe5O12 garnets resonator antennas obtained from a new procedure in the solid state ceramic technique. These ferrite resonator antennas (FRAs) had the ability to change their characteristics as a function of the applied magnetic field. The Y3Fe5O12 resonator was able to increase the antenna frequency range with application of external magnetic field. Some of the properties of dielectric resonator antennas (DRAs) can be actively controlled by using low-loss ferrite materials. When unbiased, these ferrite resonator antennas (FRAs) exhibit similar behavior to DRAs. However, when a DC magnetic bias is applied, the tensor nature of the ferrite permeability is invoked, and various parameters can be controlled electronically. We also studied the magnetic behavior of the antennas and did a numerical study of the gain and directivity of the ferrite resonator antennas. These results can be important to develop wideband third-generation (3G) cellular phones and other wireless products. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2852,2857, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23824 [source] Biomechanical findings in rats undergoing fascial reconstruction with graft materials suggested as an alternative to polypropylene ,,NEUROUROLOGY AND URODYNAMICS, Issue 3 2010M.L. Konstantinovic Abstract Aims Graft materials used for pelvic floor reinforcement should still be considered as investigational and, therefore, evaluated experimentally and within clinical trials. The present report describes our biomechanical findings in rats implanted with selected novel implant materials, which in recent years have been suggested as alternatives to plain polypropylene (PP) meshes. Methods Full thickness abdominal wall defects were primarily repaired by the implant of interest. Experiments involved eight different implant materials: two partly degradable synthetic implants, that is, a hybrid of polyglactin 910 with PP (Vypro II) and collagen coated PP (Pelvitex); two non-cross linked (Surgisis, InteX,n LP) and two cross-linked materials (Pelvicol, Pelvisoft) and two porous modifications of InteX,n LP and Pelvicol implants. At different time points (7, 14, 30, and 90 days), the implants and surrounding host tissue (explant) were harvested and tensiometry was performed. Tensile strength and location of breakage were recorded. Results In general resorbable non-cross linked collagen matrices and porous materials were weaker after 90 days; similar behavior was seen for implant materials alone and their construction with the surrounding native tissue. Both non-porous and porous modification of InteX,n LP appeared at 90 days as a very thin layer of collagen that was two-thirds, respectively one-third of the initial thickness. Conclusions In experimental conditions, sufficient strength was obtained only after 3 months, and PP containing constructs appeared as the strongest though reconstruction with Pelvicol showed comparable outcomes. Lower values for strength of non-cross linked and porous collagen materials are questioning their efficacy for pelvic floor reconstruction. Neurourol. Urodynam. 29:488,493, 2010. © 2009 Wiley-Liss, Inc. [source] Fusion,Fission Transport of Probes and Quenchers in Microdomains of an Amphiphilic Ionene Polyelectrolyte,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2007Celize M. Tcacenco In aqueous solution, amphiphilic ionenes such as the [3,22]-ionene spontaneously adopt globular conformations and form microdomains that are highly micelle-like, i.e. are capable of solubilizing organic molecules, binding and exchanging counterions and accelerating or inhibiting the rates of bimolecular reactions. Time-resolved fluorescence decay of pyrene and pyrene derivatives solubilized in these microdomains at concentrations where excimer formation occurs show that even water-insoluble probes can migrate between the hydrophobic microdomains formed in aqueous solution by a [3,22]-ionene chloride (with the N-terminal groups quaternized with benzyl chloride). Time-resolved studies of the quenching of pyrene fluorescence by alkylpyridine derivatives revealed similar behavior. The observed quenching behavior requires that the migration be between microdomains on the same ionene chain or same group of associated ionene chains and is consistent with migration dominated by fusion/fission transport of the probe and quencher. [source] Inside Back Cover (Phys. Status Solidi A 5/2010)PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 5 2010J. H. Leach The Feature Article by Morkoç and co-workers (pp. 1091,1100) centers around the not so intuitive phenomena in two types of GaN based devices, namely InGaN based LEDs and InAlN barrier GaN heterojunction FETs. In terms of the LEDs, the paper uncovers that the quantum efficiency degradation observed at high current injection levels is not necessarily of Auger recombination origin. Furthermore, nearly similar behavior of LEDs on c-plane and mplane suggests that the main driving force for the efficiency degradation is not polarization induced field either. The data along with their interpretation should set the stage for an accurate physics- based model to be developed. In terms of the FETs, the authors show that there is an optimum sheet density, which depends on drain bias or the electric field in the channel, at which the LO phonon lifetime is shortest, the velocity is highest, and the device degradation is least. The average optimum density is near 7 × 1012 cm,2 which challenges the proverbial notion that the higher the sheet density the better it is. Another outcome of this discussion is that heat dissipation takes the route of hot electrons giving off heat to LO phonons which in turn give it to LA phonons when they decay. Naturally, the shortest LO phonon lifetime is best for heat removal and thus the devices are more reliable in addition to electrons traversing at the highest velocity. [source] Pressure dependence of the optical properties of wurtzite and rock-salt Zn1,xCoxO thin filmsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 1 2007J. A. Sans Abstract In this paper we investigate the electronic structure of Zn1,xCoxO by means of optical absorption measurements under pressure. Thin films of Zn1,xCoxO with different Co content (from 1 to 30%) were prepared by pulsed laser deposition on mica substrates. Absorption spectra exhibit three main features that are clearly correlated to the Co content in the films: (i) absorption peaks in the infrared associated to crystal-field-split internal transitions in the Co 3d shell, with very small pressure coefficients due to their atomic character; (ii) a broad absorption band below the fundamental edge associated to charge transfer transitions, that exhibit relatively large pressure coefficients, indicating that the Co 3d final states must be strongly hybridized to the conduction band; and (iii) a blue-shifted fundamental absorption edge associated to band to band transitions with a pressure coefficient close to that of pure ZnO. In the up-stroke the transition pressure from wurtzite to rock-salt phase decrease almost linearly as the Co increases, from 9.5 GPa in pure ZnO to about 6.5 GPa for x = 30%. In the down-stroke pressure we observe a similar behavior, yielding a metastable rock-salt phase at room pressure, after a pressure cycle up to 15 GPa. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Extension rheology of liquid-crystalline solution/layered silicate hybridsPOLYMER ENGINEERING & SCIENCE, Issue 4 2010Gleb B. Vasilyev The extension rheology of polymer/layered silicate composites based on liquid-crystalline (LC) solution of hydroxypropylcellulose (HPC) in oligomeric polyethyleneglycole (PEG) was studied. The HPC concentration was 60 wt%. Extension experiments have been carried out for materials in the different phase states. Compositions containing Na-montmorillonite (MMT) were prepared by a two-stage method. Final systems may be attributed to solutions of HPC in PEG, which intercalates into MMT galleries. The ordered domain structure of the LC matrix as well as hydrogen-bonded network between HPC and PEG molecules significantly reduce deformation at break and provide a strong nonlinear viscoelastic behavior at extension. Appearance of isotropic phase in solutions leads to a sharp drop of the elongation viscosity. The introduction of clay into LC solution only slightly affects the viscosity value but significantly suppresses the strain-hardening scale. In contrast, loading in biphasic state of HPC-PEG solution with even small amount (1 wt%) of MMT leads to the drastic viscosity increase that does not change in further growth of the filler concentration. Elastic properties of the systems under study demonstrate the similar behavior. This effect likely is caused by the interrelationship between deformability of the LC domain structure and the network strength formed by the clay particles. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers [source] Monitoring epoxy and unsaturated polyester reactions under pressure,Reaction rates and mechanical propertiesPOLYMER ENGINEERING & SCIENCE, Issue 11 2009Javier C. Cruz The effects of pressure on reaction rates and final mechanical properties were studied for an unsaturated polyester (UP) and epoxy resin. A pressure chamber where reactions can be monitored by use of Raman spectroscopy has been built for these purposes. The chamber allows for pressures up to 13.8 MPa at 200°C. An advanced temperature control system has been adapted to the vessel to precisely control and monitor sample temperature variations and overshoots. It is described how for an accelerated UP reaction increasing pressure will result in a competing effect on the reaction rate where the rate will initially lower, but with increased pressures it may accelerate due to acceleration of the reaction rate constants. The final mechanical properties exhibit a similar behavior slightly increasing with pressure but lowering as pressure is raised further. For epoxy, it was shown that the reaction kinetics were accelerated by pressure although no mechanical property differences could be noted for the pressure ranges tested. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers. [source] Micromechanical behavior of impact modified poly(ethylene terephthalate)POLYMER ENGINEERING & SCIENCE, Issue 6 2003N. Chapleau The micromechanical behavior of poly(ethylene terephthalate), PET, modified with a metallocene polyolefin copolymer (mPE) was investigated. Uniaxial deformation tests were performed using a tensile stage in a scanning electron microscope. This technique allowed the identification of the main deformation mechanisms that are associated with energy dissipation and toughness improvement. The poly(ethylene terephthalate) was blended with 5 wt% mPE by single-screw extrusion. Films with thicknesses ranging from 200 to 500 ,m were produced. Observation of the surfaces of the films during uniaxial deformation revealed the sequence of events leading to the full yielding of the matrix. In the early stages of deformation, the particles deform together with the matrix. As the deformation is increased, cavitation inside the particles occurs and fibrillation at the particle/matrix interface is observed, as well as the onset of shear banding. In order to study the effect of interfacial adhesion of the deformation mechanisms, the PET/mPE blends were compatibilized by grafting with glycidyl methacrylate (GMA). The reduction of the particle size was significant, which is indicative of the efficiency of GMA grafting in this type of blend. In this case, the particles were difficult to detect on the surface. Cavitation and shear banding occurred simultaneously. A similar behavior was observed in the case of oriented blends. [source] If employees "go the extra mile," do customers reciprocate with similar behavior?PSYCHOLOGY & MARKETING, Issue 10 2008Youjae Yi This study proposes an integrated framework depicting the effects of two types of employee behavior (employee citizenship behavior and employee dysfunctional behavior) on customer satisfaction, which in turn, influences customer commitment. Customer satisfaction and commitment are then expected to affect two types of customer behavior (customer citizenship behavior and customer dysfunctional behavior). A survey of matched responses from 123 employees and 590 customers reveals that employee citizenship behavior, employee dysfunctional behavior, customer satisfaction, and customer commitment are important predictors of customer citizenship behavior and customer dysfunctional behavior. Furthermore, this study identifies variables (relationship age, group size, and communication frequency) that moderate the relationships being considered. The results show that the effects of two types of employee behavior on customer satisfaction are stronger when relationship age and communication frequency are higher. © 2008 Wiley Periodicals, Inc. [source] A two-mean reverting-factor model of the term structure of interest ratesTHE JOURNAL OF FUTURES MARKETS, Issue 11 2003Manuel Moreno This article presents a two-factor model of the term structure of interest rates. It is assumed that default-free discount bond prices are determined by the time to maturity and two factors, the long-term interest rate, and the spread (i.e., the difference) between the short-term (instantaneous) risk-free rate of interest and the long-term rate. Assuming that both factors follow a joint Ornstein-Uhlenbeck process, a general bond pricing equation is derived. Closed-form expressions for prices of bonds and interest rate derivatives are obtained. The analytical formula for derivatives is applied to price European options on discount bonds and more complex types of options. Finally, empirical evidence of the model's performance in comparison with an alternative two-factor (Vasicek-CIR) model is presented. The findings show that both models exhibit a similar behavior for the shortest maturities. However, importantly, the results demonstrate that modeling the volatility in the long-term rate process can help to fit the observed data, and can improve the prediction of the future movements in medium- and long-term interest rates. So it is not so clear which is the best model to be used. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23: 1075,1105, 2003 [source] Kinetic Modeling of the Autotrophic Growth of Pavlova lutheri: Study of the Combined Influence of Light and TemperatureBIOTECHNOLOGY PROGRESS, Issue 4 2003Ana P. Carvalho The optimization and control of biochemical processes require the previous establishment of mathematical models that can describe the effect of process variables on their actual kinetics. Environmental temperature is a modulating factor to which the algal cells respond continuously by adjusting their rates of cellular reactions, their nutritional requirements, and, consequently, their biomass composition. Light intensity is an exhaustible resource, indispensable to autotrophic organisms. The effects of light intensity and temperature on growth of the microalga Pavlova lutheri, which have hardly been considered to date in a simultaneous fashion, were experimentally assessed using a factorial experimental design; in this way, the effects of each variable independently and their interactions could be quantified, using maximum biomass (Xmax) or maximum specific growth rate (,max) as objective functions. The preliminary results produced indicated that light intensity plays a more important role on ,max than temperature; in the case of Xmax, both temperature and, to a lesser extent, light intensity do apparently play a role. The highest values of Xmax were associated with low temperatures and high light intensities; a similar behavior could be observed for ,max concerning light intensity, although the dependency on temperature did not seem to be as important. A more complex mechanistic model was then postulated, incorporating light and temperature as input variables, which was successfully fitted to the experimental data generated during batch cultivation of P. lutheri. [source] Reactive doping of PAni,CSA and its use in microwave absorbing materialsPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 1 2009R. S. Biscaro Abstract Conductive coatings have been studied for static dissipation and as microwave absorbing materials. The doping process of polyaniline (PAni), which makes it conductive, is an important stage that determines the coating performance. For this purpose, polyaniline was doped by reactive processing in a torque rheometer using different molar ratios between PAni and acid (PAni:CSA) at three different temperatures (80, 90, and 100°C). Aqueous solution doping was also used in the ratio of 1:2 of PAni/CSA, with the aim to investigate the influence of different methods of PAni doping on its characteristics and, consequently, on the performance of coatings. Thermal analyses of the processed materials showed that PAni doped by both routes, reactive and solution processing, showed similar behaviors. X-ray diffraction analyses showed a semicrystalline structure for the PAni,CSA doped by reactive processing using high CSA concentrations and temperature. It was also observed that the doping process affects the dispersion of the components into the conductive coatings. Microwave absorption measurements (8,12,GHz) of PU-doped PAni blends showed the dependence of the doping type, the PAni,CSA concentration, and the mixing conditions of the components on the coating performance; it was found up to 99% of attenuation of the incident radiation for some composites in a narrow frequency range. The microwave absorption efficiency of the coating samples prepared by using the reactive doping process indicates the advantage of this methodology over solution doping. Moreover, the reactive process addresses the environmental requirements. Copyright © 2008 John Wiley & Sons, Ltd. [source] Evaluation of three spatial discretization schemes with the Galewsky et al. testATMOSPHERIC SCIENCE LETTERS, Issue 3 2010Seoleun Shin Abstract We evaluate the Hamiltonian particle methods (HPM) and the Nambu discretization applied to shallow-water equations on the sphere using the test suggested by Galewsky et al. (2004). Both simulations show excellent conservation of energy and are stable in long-term simulation. We repeat the test also using the ICOSWP scheme to compare with the two conservative spatial discretization schemes. The HPM simulation captures the main features of the reference solution, but wave 5 pattern is dominant in the simulations applied on the ICON grid with relatively low spatial resolutions. Nevertheless, agreement in statistics between the three schemes indicates their qualitatively similar behaviors in the long-term integration. Copyright © 2010 Royal Meteorological Society [source] Integrating Different Perspectives on Socialization Theory and Research: A Domain-Specific ApproachCHILD DEVELOPMENT, Issue 3 2010Joan E. Grusec There are several different theoretical and research approaches to the study of socialization, characterized by frequently competing basic tenets and apparently contradictory evidence. As a way of integrating approaches and understanding discrepancies, it is proposed that socialization processes be viewed from a domain perspective, with each domain characterized by a particular form of social interaction between the object and agent of socialization and by specific socialization mechanisms and outcomes. It is argued that this approach requires researchers to identify the domain of social interaction they are investigating, to understand that phenotypically similar behaviors may belong to different domains, and to acknowledge that caregivers who are effective in one type of interaction may not be effective in another. [source] | |||||||||||||||||||||||||||||||