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Different Processes (different + process)
Terms modified by Different Processes Selected AbstractsInteraction between wind-induced seiches and convective cooling governs algal distribution in a canyon-shaped reservoirFRESHWATER BIOLOGY, Issue 7 2007RAFAEL MARCÉ Summary 1. Wind is considered the dominant factor controlling phytoplankton distribution in lentic environments. In canyon-shaped reservoirs, wind tends to blow along the main axis generating internal seiches and advective water movements that jointly with biological features of algae can produce a heterogeneous phytoplankton distribution. Turbulence generated by wind stress and convection will also affect the vertical distribution of algae, depending on their sinking properties. 2. We investigated the vertical and horizontal distribution of phytoplankton during the stratification period in Sau Reservoir (NE Spain). Sites along the main reservoir axis were sampled every 4 h for 3 days, and profiles of chlorophyll- a and temperature were made using a fluorescent FluoroProbe, which can discriminate among the main algal groups. Convective and wind shear velocity scales, and energy dissipation were calculated from meteorological data, and simulation experiments were performed to describe non-measured processes, like vertical advection and sinking velocity of phytoplankton. 3. Wind direction changed from day to night, producing a diel thermocline oscillation and an internal seiche. Energy dissipation was moderate during the night, and mainly attributed to convective cooling. During the day the energy dissipation was entirely attributed to wind shear, but values indicated low turbulence intensity. 4. The epilimnetic algal community was mainly composed of diatoms and chlorophytes. Chlorophytes showed a homogeneous distribution on the horizontal and vertical planes. Diatom horizontal pattern was also homogeneous, because the horizontal advective velocities generated by wind forcing were not high enough to develop phytoplankton gradients along the reservoir. 5. Diatom vertical distribution was heterogeneous in space and time. Different processes dominated in different regions of the reservoir, due to the interaction between seiching and the daily cycle of convective-mediated turbulence. As the meteorological forcing followed a clear daily pattern, we found very different diatom sedimentation dynamics between day and night. Remarkably, these dynamics were asynchronous in the extremes of the seiche, implying that under the same meteorological forcing a diatom population can show contrasting sedimentation dynamics at small spatial scales (approximately 103 m). This finding should be taken into account when interpreting paleolimnological records from different locations in a lake. 6. Vertical distribution of non-motile algae is a complex process including turbulence, vertical and horizontal advection, variations in the depth of the mixing layer and the intrinsic sinking properties of the organisms. Thus, simplistic interpretations considering only one of these factors should be regarded with caution. The results of this work also suggest that diatoms can persist in stratified water because of a synergistic effect between seiching and convective turbulence. [source] Reduced reproductive success and offspring survival in fragmented populations of the forest herb Phyteuma spicatumJOURNAL OF ECOLOGY, Issue 6 2005ANNETTE KOLB Summary 1Habitat fragmentation, which reduces the size and increases the isolation of populations, is a major threat to biodiversity. For Phyteuma spicatum, a self-incompatible, rare understorey herb in deciduous forests of north-western Germany, I tested the hypotheses that: (i) fitness (in terms of reproductive success) is reduced in small or isolated populations, (ii) reproduction in small populations is reduced by pollen limitation and (iii) genetic effects cause fitness reductions in small populations. 2I compared the reproductive success of plants of Phyteuma in 14 populations of different size and degree of isolation. Seed production was, as predicted, positively related to population size but was also influenced by plant size, although not by population isolation, density or habitat quality. 3I performed supplemental hand-pollinations in 10 of the 14 populations using pollen from the same population (test for pollen quantity) or from another large population (pollen quality). The proportional difference in seed production between hand-pollinated plants and open-pollinated controls increased with decreasing population size, indicating pollinator limitation of reproduction in small populations. There was no difference between the two hand-pollination treatments, suggesting that a sufficient number of cross-compatible mates was available even in the smallest populations. 4Progeny from the 14 populations were grown for 32 weeks in a common environment. There was no effect of population size on germination, but final seedling survival was positively related to population size, and this relationship was more pronounced in the glasshouse than under more favourable growing conditions in a common garden. Genetic effects may thus reduce fitness (here measured in terms of survival) in plants from small populations, making them more susceptible to environmental stress. 5The results suggest that both reproduction and offspring performance may be reduced in small populations even of long-lived species such as Phyteuma spicatum. Different processes, such as pollen limitation and genetic deterioration, may interact and affect local population dynamics and the persistence of species in fragmented landscapes. [source] Projecting group liking and ethnocentrism on in-group members: False consensus effect of attitude strengthASIAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 2 2003Minoru Karasawa The purpose of the present study was to examine the social projection effect concerning the strength of national attitudes. Japanese respondents sampled from the general population judged how patriotic and nationalistic opinions were distributed among Japanese (i.e. in-group) and American (out-group) citizens. The respondents' own positions regarding these attitude dimensions were also measured. As predicted, the respondents inflated estimates of the endorsement for positions close to their own, particularly when the target was the in-group. Estimates of opinion distributions in the out-group converged around stereotypic positions. The apparent projection effect in patriotism (i.e. in-group liking) was likely mediated by abstract trait evaluations of the home country, while the projection of nationalism (i.e. ethnocentrism) appeared to be a direct result of projection without such mediation. Different processes such as the motivation for cognitive consistency and the need to achieve social identity of the group were suggested to underlie projection effects in different domains. Implications of the results for the study of stereotyping and intergroup conflict are discussed. [source] Offline adaptive radiotherapy for bladder cancer using cone beam computed tomographyJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2009F Foroudi Summary We investigated if an adaptive radiotherapy approach based on cone beam CT (CBCT) acquired during radical treatment was feasible and resulted in improved dosimetric outcomes for bladder cancer patients compared to conventional planning and treatment protocol. A secondary aim was to compare a conventional plan with a theoretical online process where positioning is based on soft tissue position on a daily basis and treatment plan choice is based on bladder size. A conventional treatment plan was derived from a planning CT scan in the radical radiotherapy of five patients with muscle invasive bladder cancer. In this offline adaptive protocol using CBCT, the patients had 10 CBCT: daily CBCT for the first five fractions and then CBCT scan on a weekly basis. The first five daily CBCT in each patient were used to create a single adaptive plan for treatment from fraction eight onwards. A different process using the planning CT and the first five daily CBCT was used to create small, average and large bladder volumes, giving rise to small, average and large adaptive bladder treatment plans, respectively. In a retrospective analysis using the CBCT scans, we compared the clinical target volume (CTV) coverage using three protocols: (i) conventional; (ii) offline adaptive; and (iii) online adaptive with choice of ,plan of the day'. Daily CBCT prolonged treatment time by an average of 7 min. Two of the five patients demonstrated such variation in CTV that an offline adaptive plan was used for treatment after the first five CBCT. Comparing the offline adaptive plan with the conventional plan, the CTV coverage improved from a minimum of 60.1 to 94.7% in subsequent weekly CBCT. Using the CBCT data, modelling an online adaptive protocol showed that coverage of the CTV by the 95% prescribed dose line by small, medium and large adaptive plans were 34.9, 67.4 and 90.7% of occasions, respectively. More normal tissue was irradiated using a conventional CTV to planning target volume margin (1.5 cm) compared to an online adaptive process (0.5 cm). An offline adaptive strategy improves dose coverage in certain patients to the CTV and results in a higher conformity index compared to conventional planning. Further research in online adaptive radiation therapy for bladder cancer is indicated. [source] Robust Estimation and Outlier Detection for Overdispersed Multinomial Models of Count DataAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 2 2004Walter R. Mebane Jr. We develop a robust estimator,the hyperbolic tangent (tanh) estimator,for overdispersed multinomial regression models of count data. The tanh estimator provides accurate estimates and reliable inferences even when the specified model is not good for as much as half of the data. Seriously ill-fitted counts,outliers,are identified as part of the estimation. A Monte Carlo sampling experiment shows that the tanh estimator produces good results at practical sample sizes even when ten percent of the data are generated by a significantly different process. The experiment shows that, with contaminated data, estimation fails using four other estimators: the nonrobust maximum likelihood estimator, the additive logistic model and two SUR models. Using the tanh estimator to analyze data from Florida for the 2000 presidential election matches well-known features of the election that the other four estimators fail to capture. In an analysis of data from the 1993 Polish parliamentary election, the tanh estimator gives sharper inferences than does a previously proposed heteroskedastic SUR model. [source] Plasticity of the visual system after early brain damageDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2010ANDREA GUZZETTA The aim of this review is to discuss the existing evidence supporting different processes of visual brain plasticity after early damage, as opposed to damage that occurs during adulthood. There is initial evidence that some of the neuroplastic mechanisms adopted by the brain after early damage to the visual system are unavailable at a later stage. These are, for example, the ability to differentiate functional tissue within a larger dysplastic cortex during its formation, or to develop new thalamo-cortical connections able to bypass the lesion and reach their cortical destination in the occipital cortex. The young brain also uses the same mechanisms available at later stages of development but in a more efficient way. For example, in people with visual field defects of central origin, the anatomical expansion of the extrastriatal visual network is greater after an early lesion than after a later one, which results in more efficient mechanisms of visual exploration of the blind field. A similar mechanism is likely to support some of the differences found in people with blindsight, the phenomenon of unconscious visual perception in the blind field. In particular, compared with people with late lesions, those with early brain damage appear to have stronger subjective awareness of stimuli hitting the blind visual field, reported as a conscious feeling that something is present in the visual field. Expanding our knowledge of these mechanisms could help the development of early therapeutic interventions aimed at supporting and enhancing visual reorganization at a time of greatest potential brain plasticity. [source] Quantifying sediment storage in a high alpine valley (Turtmanntal, Switzerland)EARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2009Jan-Christoph Otto Abstract The determination of sediment storage is a critical parameter in sediment budget analyses. But, in many sediment budget studies the quantification of magnitude and time-scale of sediment storage is still the weakest part and often relies on crude estimations only, especially in large drainage basins (>100,km2). We present a new approach to storage quantification in a meso-scale alpine catchment of the Swiss Alps (Turtmann Valley, 110,km2). The quantification of depositional volumes was performed by combining geophysical surveys and geographic information system (GIS) modelling techniques. Mean thickness values of each landform type calculated from these data was used to estimate the sediment volume in the hanging valleys and the trough slopes. Sediment volume of the remaining subsystems was determined by modelling an assumed parabolic bedrock surface using digital elevation model (DEM) data. A total sediment volume of 781·3×106,1005·7×106,m3 is deposited in the Turtmann Valley. Over 60% of this volume is stored in the 13 hanging valleys. Moraine landforms contain over 60% of the deposits in the hanging valleys followed by sediment stored on slopes (20%) and rock glaciers (15%). For the first time, a detailed quantification of different storage types was achieved in a catchment of this size. Sediment volumes have been used to calculate mean denudation rates for the different processes ranging from 0·1 to 2·6,mm/a based on a time span of 10,ka. As the quantification approach includes a number of assumptions and various sources of error the values given represent the order of magnitude of sediment storage that has to be expected in a catchment of this size. Copyright © 2009 John Wiley & Sons, Ltd. [source] Monitoring and predicting channel change in a free-evolving, small Alpine river: Ridanna Creek (North East Italy)EARTH SURFACE PROCESSES AND LANDFORMS, Issue 14 2007Rossella Luchi Abstract The recent (25 years) morphodynamics of a proglacial reach of the Ridanna Creek, North-East Italy, evolving in the absence of human constraints, has been investigated by means of an intensive field activity and of the analysis of aerial photographs. The study reach mostly displays a braided morphology, with sharp downstream variations of valley gradient, sediment size and formative conditions within the main channel. These discontinuities are associated with different processes of channel adjustment at different timescales, which have been quantified by coupling hydrological with morphological information. Several processes of channel change and variations in braiding intensity have been documented along the whole reach and highlight how a regular, weakly meandering main channel may significantly affect the morphodynamics of the braided network. A first attempt to predict the morphological instability of this main channel at the observed spatial scales through existing linear theories of curved river channels shows a good agreement with field observations. Finally, the complete hydro-morphodynamical characterization of such an undisturbed alpine river reach can provide a relevant contribution to the definition of reference conditions for Alpine rivers required by the EU Water Framework Directive. Copyright © 2007 John Wiley & Sons, Ltd. [source] Parasites lost , do invaders miss the boat or drown on arrival?ECOLOGY LETTERS, Issue 4 2010Catriona J. MacLeod Ecology Letters (2010) 13: 516,527 Abstract Host species that colonize new regions often lose parasite species. Using population arrival and establishment data for New Zealand's introduced bird species and their ectoparasitic chewing lice species, we test the relative importance of different processes and mechanisms in causing parasite species loss. Few lice failed to arrive in New Zealand with their hosts due to being missed by chance in the sample of hosts from the original population (missing the boat). Rather, most lice were absent because their hosts or the parasite themselves failed to establish populations in their new environment. Given they arrived and their host established, parasite persistence was more strongly related to factors associated with transmission efficiency (number of host individuals introduced, host body size, host sociality and parasite suborder) than parasite propagule pressure and aggregation. Such insights into parasite success are invaluable to both understanding and managing their impact. [source] The metacommunity concept: a framework for multi-scale community ecologyECOLOGY LETTERS, Issue 7 2004M. A. Leibold Abstract The metacommunity concept is an important way to think about linkages between different spatial scales in ecology. Here we review current understanding about this concept. We first investigate issues related to its definition as a set of local communities that are linked by dispersal of multiple potentially interacting species. We then identify four paradigms for metacommunities: the patch-dynamic view, the species-sorting view, the mass effects view and the neutral view, that each emphasizes different processes of potential importance in metacommunities. These have somewhat distinct intellectual histories and we discuss elements related to their potential future synthesis. We then use this framework to discuss why the concept is useful in modifying existing ecological thinking and illustrate this with a number of both theoretical and empirical examples. As ecologists strive to understand increasingly complex mechanisms and strive to work across multiple scales of spatio-temporal organization, concepts like the metacommunity can provide important insights that frequently contrast with those that would be obtained with more conventional approaches based on local communities alone. [source] Integrated condition indices as a measure of whole effluent toxicity in zebrafish (Danio rerio)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2002Roel Smolders Abstract Toxic exposure of organisms interferes with organismal integrity at the biochemical level and ultimately gives rise to effects at the individual level. These effects may result in reductions in ecologically relevant characteristics such as growth, reproduction, and survival. A chronic toxicity test with zebrafish (Danio rerio) was conducted where fish were exposed to 50, 75, and 100% effluent for 28 d under flow-through conditions. Effects of effluent exposure were determined using endpoints of physiological (respiration during swimming), growth (condition, length, and weight), and reproductive (spawning and hatching) processes within the same population. Results clearly indicate that the condition and growth of zebrafish is depressed by exposure to the effluent. Also, increased oxygen consumption was found after 14, 21, and 28 d of exposure. Reproduction proved to correlate well with the condition of the motherfish in the control, and spawning and hatching were significantly depressed by effluent exposure. These results indicate that the evaluation of endpoints describing different ecologically relevant processes provides a rational assessment of the cause,effect relationships of effluent toxicity. This approach can quantify effects on different biological processes and can determine the interactions that occur between these different processes. [source] Cycloadditions and Methylene Transfer in Reactions of Substituted Thiocarbonyl S -Methylides with Thiobenzophenone: A Computational StudyEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2005Reiner Sustmann Abstract Regiochemistry and methylene transfer reactions in cycloadditions of aliphatic thiocarbonyl S -methylides and thiobenzophenone are analyzed by ab initio [(U)HF/3-21G*] and DFT calculations [(U)B3LYP/6-31G*//(U)HF/3-21G* and (U)B3LYP/6-31G*]. The formation of regioisomeric 1,3-dithiolanes is explained by the competition of concerted (2,4-substituted 1,3-dithiolane) and stepwise cycloaddition via C,C -biradicals (4,5-substituted 1,3-dithiolane). Aliphatic thiocarbonyl S -methylides with sterically demanding substituents undergo substantial methylene transfer in the reaction with thiobenzophenone. This process involves dissociation of the C,C -biradical intermediate with liberation of thiobenzophenone S -methylide which, in turn, combines with a second molecule of thiobenzophenone. Calculated activation parameters for the different processes are in agreement with the experimental observations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] A METAPOPULATION PERSPECTIVE ON GENETIC DIVERSITY AND DIFFERENTIATION IN PARTIALLY SELF-FERTILIZING PLANTSEVOLUTION, Issue 12 2002Pärk. Ingvarsson Abstract., Partial self-fertilization is common in higher plants. Mating system variation is known to have important consequences for how genetic variation is distributed within and among populations. Selfing is known to reduce effective population size, and inbreeding species are therefore expected to have lower levels of genetic variation than comparable out crossing taxa. However, several recent empirical studies have shown that reductions in genetic diversity within populations of inbreeding species are far greater than the expected reductions based on the reduced effective population size. Two different processes have been argued to cause these patterns, selective sweeps (or hitchhiking) and background selection. Both are expected to be most effective in reducing genetic variation in regions of low recombination rates. Selfing is known to reduce the effective recombination rate, and inbreeding taxa are thus thought to be particularly vulnerable to the effects of hitchhiking or background selection. Here I propose a third explanation for the lower-than-expected levels of genetic diversity within populations of selfing species; recurrent extinctions and recolonizations of local populations, also known as metapopulation dynamics. I show that selfing in a metapopulation setting can result in large reductions in genetic diversity within populations, far greater than expected based the lower effective population size inbreeding species is expected to have. The reason for this depends on an interaction between selfing and pollen migration. [source] Application of Electrochemical Impedance Spectroscopy for Fuel Cell Characterization: PEFC and Oxygen Reduction Reaction in Alkaline Solution,FUEL CELLS, Issue 3 2009N. Wagner Abstract The most common method used to characterise the electrochemical performance of fuel cells is the recording of current/voltage U(i) curves. Separation of electrochemical and ohmic contributions to the U(i) characteristics requires additional experimental techniques like electrochemical impedance spectroscopy (EIS). The application of EIS is an approach to determine parameters which have proved to be indispensable for the characterisation and development of all types of fuel cell electrodes and electrolyte electrode assemblies [1]. In addition to EIS semi-empirical approaches based on simplified mathematical models can be used to fit experimental U(i) curves [2]. By varying the operating conditions of the fuel cell and by the simulation of the measured EIS with an appropriate equivalent circuit, it is possible to split the cell impedance into electrode impedances and electrolyte resistance. Integration in the current density domain of the individual impedance elements enables the calculation of the individual overpotentials in the fuel cell (PEFC) and the assignment of voltage loss to the different processes. In case of using a three electrode cell configuration with a reference electrode, one can directly determine the corresponding overvoltage. For the evaluation of the measured impedance spectra the porous electrode model of Göhr [3] was used. This porous electrode model includes different impedance contributions like impedance of the interface porous layer/pore, interface porous layer/electrolyte, interface porous layer/bulk, impedance of the porous layer and impedance of the pores filled by electrolyte. [source] Karst Spring Responses Examined by Process-Based ModelingGROUND WATER, Issue 6 2006Steffen Birk Ground water in karst terrains is highly vulnerable to contamination due to the rapid transport of contaminants through the highly conductive conduit system. For contamination risk assessment purposes, information about hydraulic and geometric characteristics of the conduits and their hydraulic interaction with the fissured porous rock is an important prerequisite. The relationship between aquifer characteristics and short-term responses to recharge events of both spring discharge and physicochemical parameters of the discharged water was examined using a process-based flow and transport model. In the respective software, a pipe-network model, representing fast conduit flow, is coupled to MODFLOW, which simulates flow in the fissured porous rock. This hybrid flow model was extended to include modules simulating heat and reactive solute transport in conduits. The application of this modeling tool demonstrates that variations of physicochemical parameters, such as solute concentration and water temperature, depend to a large extent on the intensity and duration of recharge events and provide information about the structure and geometry of the conduit system as well as about the interaction between conduits and fissured porous rock. Moreover, the responses of solute concentration and temperature of spring discharge appear to reflect different processes, thus complementing each other in the aquifer characterization. [source] A pH-Gating Ionic Transport Nanodevice: Asymmetric Chemical Modification of Single NanochannelsADVANCED MATERIALS, Issue 22 2010Xu Hou Inspired by biological ion channels, the generation of artificial nanochannels has strong implications for the simulation of different processes of ionic transport as well as enhance the functionality of biological ion channels. Here, we show plasma asymmetric chemical modification approach to prepare the pH asymmetric gating nanochannel that can achieve pH control for both different ionic rectification and perfect gating function, simultaneously. [source] Brain mechanisms of involuntary visuospatial attention: An event-related potential studyHUMAN BRAIN MAPPING, Issue 4 2005Shimin Fu Abstract The brain mechanisms mediating visuospatial attention were investigated by recording event-related potentials (ERPs) during a line-orientation discrimination task. Nonpredictive peripheral cues were used to direct participant's attention involuntarily to a spatial location. The earliest attentional modulation was observed in the P1 component (peak latency about 130 ms), with the valid trials eliciting larger P1 than invalid trials. Moreover, the attentional modulations on both the amplitude and latency of the P1 and N1 components had a different pattern as compared to previous studies with voluntary attention tasks. In contrast, the earliest visual ERP component, C1 (peak latency about 80 ms), was not modulated by attention. Low-resolution brain electromagnetic tomography (LORETA) showed that the earliest attentional modulation occurred in extrastriate cortex (middle occipital gyrus, BA 19) but not in the primary visual cortex. Later attention-related reactivations in the primary visual cortex were found at about 110 ms after stimulus onset. The results suggest that involuntary as well as voluntary attention modulates visual processing at the level of extrastriate cortex; however, at least some different processes are involved by involuntary attention compared to voluntary attention. In addition, the possible feedback from higher visual cortex to the primary visual cortex is faster and occurs earlier in involuntary relative to voluntary attention task. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source] Modelling the hydrology of a catchment using a distributed and a semi-distributed modelHYDROLOGICAL PROCESSES, Issue 3 2005Ahmed Abu El-Nasr Abstract Various hydrological models exist that describe the phases in the hydrologic cycle either in an empirical, semi-mechanistic or fully mechanistic way. The way and level of detail for the different processes of the hydrologic cycle that needs to be described depends on the objective, the application and the availability of data. In this study the performance of two different models, the fully distributed MIKE SHE model and the semi-distributed SWAT model, was assessed. The aim of the comparative study was to examine if both models are equally able to describe the different phases in the hydrologic cycle of a catchment, given the availability of hydrologic data in the catchment. For the comparison, historic data of the Jeker river basin, situated in the loamy belt region of Belgium, was used. The size of the catchment is 465 km2. The landscape is rolling, the dominant land use is farmland, and the soils vary from sandy-loam to clay-loam. The daily data of a continuous period of 6 years were used for the calibration and validation of both models. The results were obtained by comparing the performance of the two models using a qualitative (graphical) and quantitative (statistical) assessment, such as graphical representation of the observed and simulated river discharge, performance indices, the hydrograph maxima, the baseflow minima, the total accumulated volumes and the extreme value distribution of river flow data. The analysis revealed that both models are able to simulate the hydrology of the catchment in an acceptable way. The calibration results of the two tested models, although they differ in concept and spatial distribution, are quite similar. However, the MIKE SHE model predicts slightly better the overall variation of the river flow. Copyright © 2005 John Wiley & Sons, Ltd. [source] The Colours of MoleculesIMAGING & MICROSCOPY (ELECTRONIC), Issue 1 2006Chemical Force Microscopy Enables a New Look on Surfaces Abstract As the surface functionality is gaining more and more relevance in modern surface technology, the need for an analytical tool with chemical sensitivity and high lateral resolution is becoming important more than ever. In this article, we introduce the novel method "Chemical Force Microscopy" (CFM), which is enabling the chemical mapping of the surface with nm-resolution for the first time. This method has proved to be efficient to optimise and understand different processes on industrial surfaces. In the fields like plasma, coating, cell biology, pharmaceutical and printing technologies, this method has shown to be supremely efficient. [source] Multiple myeloma biology: lessons from the 5TMM modelsIMMUNOLOGICAL REVIEWS, Issue 1 2003Karin Vanderkerken Summary:, Multiple myeloma (MM) is a B cell neoplasm characterized by the monoclonal proliferation of plasma cells in the bone marrow, the development of osteolytic lesions and the induction of angiogenesis. These different processes require three-dimensional interactions, with both humoral and cellular contacts. The 5TMM models are suitable models to study these interactions. These murine models originate from spontaneously developed myeloma in elderly mice, which are propagated by in vivo transfer of the myeloma cells into young syngeneic mice. In this review we report on studies performed in the 5TMM models with special emphasis on the homing of the myeloma cells, the characterization of the migrating and proliferating clone and the identification of the isotype switch variants. The bone marrow microenvironment was further targeted with osteoprotegerin (OPG) to block the RANK/RANKL/OPG system and with potent bisphosphonates. Both treatments resulted in a significant protection against myeloma-associated bone disease, and they decreased myeloma disease, as evidenced by a lower tumor load and an increased survival of the mice. These different studies demonstrate the strength of these models, not only in unraveling basic biological processes but also in the testing of potentially new therapeutic targets. [source] A taxonomy of political processes in systems developmentINFORMATION SYSTEMS JOURNAL, Issue 5 2010Rajiv Sabherwal Abstract Significant resources invested in information system development (ISD) are wasted due to political manoeuvres. Prior research on ISD politics has contributed mainly through theoretical development and case studies. This has enhanced understanding of relevant concepts, political tactics and conditions facilitating politics. However, there is limited understanding of the different processes through which politics unfold. This paper uses 89 ISD projects to develop a taxonomy of political processes in ISD. The taxonomy includes three distinct processes: Tug of War, wherein multiple parties strive to gain project control; Obstacle Race, which involves efforts to resist and pursue the project; and Empire Building, wherein the project is used as an instrument to enhance political or resource bases. The taxonomy is explained using the non-proponents' view of the project and the balance of power between system's proponents and non-proponents. We also discuss the emergent taxonomy's implications for how politics can be managed and studied. [source] Formation of Lipid Emulsions and Clear Gels by Liquid Crystal EmulsificationINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2007T. Suzuki Recently developed emulsion technologies for the formation of fine emulsions, lipid emulsions and clear gels by liquid crystal emulsification were reviewed. As a basic information on liquid crystal emulsification, the structures and characteristic behaviours of lyotropic liquid crystals were summarized. Formation of a liquid crystalline phase was often seen in emulsions and biological systems. The significance of liquid crystal formation during emulsification was analysed by comparing the states and stabilities of emulsions prepared by different processes. Then uses of liquid crystals for formation of the characteristic emulsions and gels were also discussed. In liquid crystal emulsification, an oil phase is dispersed directly into the lamellar liquid-crystalline phase composed of surfactant, glycerol and water to prepare a gel-like oil-in-liquid crystal emulsion. This is followed by dilution with the remaining water to produce an emulsion. From the phase behaviour during emulsification and analysis of the local motion of the liquid crystal membrane by fluorometry, it was confirmed that the interaction between surfactant and a polyol molecule such as glycerol promotes hydrogen bonding and enhances the strength of the lamellar liquid crystal membranes, which results in the formation of oil-in-liquid crystal emulsions. The interaction between the liquid crystal and oil was analysed from the changes in molecular motion of the membrane at the oil-liquid crystal interface using the spin label technique of electron spin resonance (ESR). The fluidity of the liquid crystal membrane did not change when oil was added, and therefore oil-in-liquid crystal emulsions of various oils were prepared by the identical process. This lack of dependence of the liquid crystal membrane on oil results in the unique properties of liquid crystal emulsification, which can be used for oils of various polarity and different molecular constituents. When a self-organizing artificial stratum corneum lipid containing pseudo-ceramide was used as a principal component of the oil, a multilamellar emulsion of concentric lamellar structure was formed. The multilamellar emulsion supplements the physiological function of stratum corneum by the identical mechanism as natural intercellular lipids. High-pressure treatment of the lipid emulsion produced a gel-like emulsion crystal, in which the homogeneous nanoemulsion droplets were arranged in a hexagonal array. This review paper was presented at the Conference of the Asian Societies of Cosmetic Scientists 2005 in Bangkok. [source] The hydrophilic, foaming and emulsifying properties of casein concentrates produced by various methodsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2006Janesca A. Roman Summary The hydrophilic and surfactant properties of casein concentrates made by different processes such as isoelectric precipitation and neutralization (commercial casein, CC) coagulation by rennet (casein clots, COC) and microfiltration/diafiltration (casein micelles, CM) were studied. Water absorption capacity (WAC), water solubility (WS) and water-holding capacity (WHC) were highest for CM and lowest for COC. Solubility was higher in water and in pH 5.5, 0.10 m NaCl solution for both CM and COC. Foaming capacity was better for CM than for CC at pH 4.0 and for CC at pH 6.0 and 8.0. Foam stability was low for both CM and CC at pH 4.0 but it was high for CM at pH 6.0 and 8.0 and for CC in the absence of salt. Emulsifying capacity was higher for CC at pH 4.0 and 7.0. Stability of emulsion was high for CC at pH 4.0 and for CM at pH 7.0. [source] Flavour encapsulation and controlled release , a reviewINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2006Atmane Madene Summary Flavours can be among the most valuable ingredients in any food formula. Even small amounts of some aroma substance can be expensive, and because they are usually delicate and volatile, preserving them is often a top concern of food manufacturers. Encapsulation describes different processes to cover an active compound with a protective wall material and it can be employed to treat flavours so as to impart some degree of protection against evaporation, reaction, or migration in a food. Encapsulation of flavours has been attempted and commercialized using many different methods such as spray drying, spray chilling or spray cooling, extrusion, freeze drying, coacervation and molecular inclusion. The choice of appropriate microencapsulation technique depends upon the end use of the product and the processing conditions involved in the manufacturing product. This overview describes each method cited above in terms of the basic chemical and/or physical principles involved and covers mechanisms of flavour release from food matrices. [source] Differential age-related change of prose memory in older Hong Kong Chinese of higher and lower educationINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 3 2004T. M. C. Lee Abstract Background Memory difficulty is one of the most common complaints of older people, with or without psychiatric conditions. It is therefore of utmost important to understand how normal ageing process impacts upon prose memory so as to gain insight into ways to differentiate pathological vs normal age-related changes of the recall of prose observed among older people. Objectives To understand the differential age-related change of prose memory in older Hong Kong Chinese of higher and lower education. Method Forty-eight normal, healthy Cantonese-speaking Chinese were recruited. Seventeen of them were younger, highly educated participants. Among the 31 older people recruited, 19 of them received education comparable with the younger participants and 12 were older people of low education. A prose passage was constructed to measure the different processes of prose memory, including learning efficiency, rate of forgetting, recall accuracy, accuracy of temporal sequence of information recalled, distortions, and recognition memory. Results As expected, ageing affected all the processes of prose memory measured, except the rate of forgetting. Apart from learning efficiency and rate of forgetting, education was observed to modify the effect of ageing on all the processes studied. Conclusions Changes of prose memory associated with ageing and the differential effect of education on prose recall among older people were discussed. The findings seem to suggest that prose memory is a multifaceted construct. Copyright © 2004 John Wiley & Sons, Ltd. [source] Local identification of prototypes for genetic learning of accurate TSK fuzzy rule-based systemsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 9 2007R. Alcalá This work presents the use of local fuzzy prototypes as a new idea to obtain accurate local semantics-based Takagi,Sugeno,Kang (TSK) rules. This allow us to start from prototypes considering the interaction between input and output variables and taking into account the fuzzy nature of the TSK rules. To do so, a two-stage evolutionary algorithm based on MOGUL (a methodology to obtain Genetic Fuzzy Rule-Based Systems under the Iterative Rule Learning approach) has been developed to consider the interaction between input and output variables. The first stage performs a local identification of prototypes to obtain a set of initial local semantics-based TSK rules, following the Iterative Rule Learning approach and based on an evolutionary generation process within MOGUL (taking as a base some initial linguistic fuzzy partitions). Because this generation method induces competition among the fuzzy rules, a postprocessing stage to improve the global system performance is needed. Two different processes are considered at this stage, a genetic niching-based selection process to remove redundant rules and a genetic tuning process to refine the fuzzy model parameters. The proposal has been tested with two real-world problems, achieving good results. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 909,941, 2007. [source] Gender and Negotiation: Some Experimental Findings from an International Negotiation Simulation1INTERNATIONAL STUDIES QUARTERLY, Issue 1 2009Mark A. Boyer Increasingly, scholars have taken note of the tendency for women to conceptualize issues such as security, peace, war, and the use of military force in different ways than their male counterparts. These divergent conceptualizations in turn affect the way women interact with the world around them and make decisions. Moreover, research across a variety of fields suggests that providing women a greater voice in international negotiations may bring a fresh outlook to dispute resolution. Using experimental data collected by the GlobalEd Project, this article provides substantial support for hypotheses positing that females generate significantly different processes and outcomes in a negotiation context. These findings occur both in terms of female negotiation behavior and the impact of females as negotiation facilitators/mediators. [source] Critical Junctures and Social Identity Theory: Explaining the Gap between Danish Mass and Elite Attitudes to EuropeanizationJCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 2 2005TRINE FLOCKHART By applying a combination of a social constructivist perspective on ideational change with theories of social learning and social identity, the article explains the gap in the Danish discourse on Europe between mass and elite. The Danish population is conceptualized as two differently constructed ,social groups' consisting of a nation people and a state-elite group. Each ,social group' has experienced different processes of ideational change and socialization and has developed different conceptions of interests and political preferences. [source] The Minimum Data Set Weight-Loss Quality Indicator: Does It Reflect Differences in Care Processes Related to Weight Loss?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 10 2003Sandra F. Simmons PhD Objectives: To determine whether nursing homes (NHs) that score differently on prevalence of weight loss, according to a Minimum Data Set (MDS) quality indicator, also provide different processes of care related to weight loss. Design: Cross-sectional. Setting: Sixteen skilled nursing facilities: 11 NHs in the lower (25th percentile,low prevalence) quartile and five NHs in the upper (75th percentile,high prevalence) quartile on the MDS weight-loss quality indicator. Participants: Four hundred long-term residents. Measurements: Sixteen care processes related to weight loss were defined and operationalized into clinical indicators. Trained research staff conducted measurement of NH staff implementation of each care process during assessments on three consecutive 12-hour days (7 a.m. to 7 p.m.), which included direct observations during meals, resident interviews, and medical record abstraction using standardized protocols. Results: The prevalence of weight loss was significantly higher in the participants in the upper quartile NHs than in participants in the lower quartile NHs based on MDS and monthly weight data documented in the medical record. NHs with a higher prevalence of weight loss had a sig-nificantly larger proportion of residents with risk factors for weight loss, namely low oral food and fluid intake. There were few significant differences on care process measures between low- and high-weight-loss NHs. Staff in low-weight-loss NHs consistently provided verbal prompting and social interaction during meals to a greater proportion of residents, including those most at risk for weight loss. Conclusion: The MDS weight-loss quality indicator reflects differences in the prevalence of weight loss between NHs. NHs with a lower prevalence of weight loss have fewer residents at risk for weight loss and staff who provide verbal prompting and social interaction to more residents during meals, but the adequacy and quality of feeding assistance care needs improvement in all NHs. [source] Resolution of two-way data from spectroscopic monitoring of reaction or process systems by parallel vector analysis (PVA) and window factor analysis (WFA): inspection of the effect of mass balance, methods and simulationsJOURNAL OF CHEMOMETRICS, Issue 3 2003Jian-Hui Jiang Abstract The effect of mass balance on the analysis of two-way data of reaction or process systems is investigated. It is shown that the rank-deficient species-related bilinear model can be converted to a full-rank reaction-related bilinear model, and in general situations the chemical rank for a system is the number of reactions plus one. Two slightly modified procedures are thus suggested to extract the spectral subspaces essential for resolution and to ascertain the number of reactions in different time domains. Based on the reaction-related bilinear model, a procedure of window factor analysis (WFA) is implemented for resolving the extent curves of reactions. A new two-way resolution approach, parallel vector analysis (PVA), is also developed. The idea of PVA is to construct a set of subspaces comprising only one common (spectral) component and then find a vector that is in parallel with a series of vectors coming from different subspaces. With suitably constructed subspaces the PVA procedure offers a versatile avenue to approach the unique resolution of spectral profiles. A four-component system which comprises four different processes or reactions is simulated. Results obtained reveal that favorable resolution is achieved for the spectral and concentration profiles by the suggested procedures of WFA and PVA. 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