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Mobility
Kinds of Mobility Terms modified by Mobility Selected AbstractsDESTINATION EFFECTS: RESIDENTIAL MOBILITY AND TRAJECTORIES OF ADOLESCENT VIOLENCE IN A STRATIFIED METROPOLIS,CRIMINOLOGY, Issue 3 2010PATRICK SHARKEY Two landmark policy interventions to improve the lives of youth through neighborhood mobility,the Gautreaux program in Chicago and the Moving to Opportunity (MTO) experiments in five cities,have produced conflicting results and have created a puzzle with broad implications: Do residential moves between neighborhoods increase or decrease violence, or both? To address this question, we analyze data from a subsample of adolescents ages 9,12 years from the Project on Human Development in Chicago Neighborhoods, a longitudinal study of children and their families that began in Chicago,the site of the original Gautreaux program and one of the MTO experiments. We propose a dynamic modeling strategy to separate the effects of residential moving across three waves of the study from dimensions of neighborhood change and metropolitan location. The results reveal countervailing effects of mobility on trajectories of violence; whereas neighborhood moves within Chicago lead to an increased risk of violence, moves outside the city reduce violent offending and exposure to violence. The gap in violence between movers within and outside Chicago is explained not only by the racial and economic composition of the destination neighborhoods but also by the quality of school contexts, adolescents' perceived control over their new environment, and fear. These findings highlight the need to simultaneously consider residential mobility, mechanisms of neighborhood change, and the wider geography of structural opportunity. [source] INTERNATIONAL CAPITAL MOBILITY AND TRADE POLITICS: CAPITAL FLOWS, POLITICAL COALITIONS, AND LOBBYINGECONOMICS & POLITICS, Issue 3 2004Michael J. Hiscox Conventional wisdom holds that increasing international capital mobility reduces incentives for firms to lobby for trade protection. This paper argues that the effects of increased international capital mobility on the lobbying incentives of firms depend critically upon levels of inter-industry mobility. General-equilibrium analysis reveals that if capital is highly industry-specific, greater international mobility among some types of specific capital may increase lobbying incentives for owners of other specific factors and thereby intensify industry-based rent-seeking in trade politics. Evidence on levels of inward and outward investment in US manufacturing industries between 1982 and 1996, and on industry lobbying activities, indicate that these effects may be quite strong. [source] ,MOVING AROUND': THE SOCIAL AND SPATIAL MOBILITY OF YOUTH IN LUSAKAGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3 2008Katherine V. Gough ABSTRACT Claims have recently been made for a ,mobilities paradigm' which is challenging the relative ,a-mobile' focus of much of the social sciences. The agenda drawn up for this mobilities paradigm is clearly based on Northern trends with little consideration of the South. African populations have always been mobile but little is known about the mobility of urban populations and in particular of the youth, who constitute a large proportion of the population. This paper explores the daily and residential mobility of young people in Lusaka building upon interviews held with low- and middle-income youth. The aim is to contribute to discussions of: how mobility varies by gender and class; the links between spatial mobility and social and economic mobility; the nature of the relationship between patterns of mobility and residential structure; and how examining mobility can illuminate many other aspects of young people's lives. Overall the picture emerging from Lusaka is rather bleak. In a context of spiralling economic decline and rising HIV/AIDS rates, the social mobility of youth is predominantly downwards which is reflected in the residential and daily mobility patterns of the young people. There is a strong link between young people's mobility and their livelihoods, an aspect of mobility that is widespread in the South but largely overlooked by the emerging mobilities paradigm. [source] ARCHITECTURAL GEOGRAPHIES OF THE AIRPORT BALCONY: MOBILITY, SENSATION AND THE THEATRE OF FLIGHTGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 1 2008Peter Adey ABSTRACT. Contemporary studies within the apparent ,mobility turn' focus upon airports as sites indicative of our mobile world, yet they tend to forgo investigations of the contextual architectural geographies that shape and inflect these mobilities. This paper examines the relationship between the architecture of the airport balcony and practices of seeing. While recent scholarship has taken airports to be incredible symbolizers of power and places of heightened visual scrutiny, the paper explores how through the architectural mediation of seeing, early airports were designed to instil specific inspirations, beliefs and messages within the airport user , constructing a new and modern experience. Far from a blank space evacuated of social presence and meaning, the paper investigates how airport design interacts with and shapes social experience. By examining the mobile practices and experiences of inhabiting the airport balcony, the paper advances conceptualizations of moving and seeing by complicating their practice as ,collective individuations' of social, architectural and sensual engagements, registers, and percepts. [source] RISING OCCUPATIONAL AND INDUSTRY MOBILITY IN THE UNITED STATES: 1968,97,INTERNATIONAL ECONOMIC REVIEW, Issue 1 2008Gueorgui Kambourov We document and analyze the high level and the substantial increase in worker mobility in the United States over the 1968,97 period at various levels of occupational and industry aggregation. This is important in light of the recent findings that human capital of workers is largely occupation- or industry-specific. To control for measurement error in occupation and industry coding, we develop a method that utilizes the PSID Retrospective Occupation-Industry Supplemental Data Files. We emphasize the importance of our findings for understanding a number of issues such as the changes in wage inequality, aggregate productivity, job stability, and life-cycle earnings profiles. [source] INCORPORATING TECHNOLOGY DIFFUSION, FACTOR MOBILITY AND STRUCTURAL CHANGE INTO CROSS-REGION GROWTH REGRESSION: AN APPLICATION TO CHINA,JOURNAL OF REGIONAL SCIENCE, Issue 3 2010Laixiang Sun ABSTRACT This paper advocates a spatial dynamic model that introduces technology diffusion, factor mobility, and structural change into the cross-region growth regression. The spatial setting is derived from theory rather than spatial statistical tests. An application of this model to the study of cross-province growth in China over the period 1980,2005 indicates that incomes are spatially correlated, which highlights the significance of technology diffusion and factor mobility. Furthermore, the integration of neoclassical growth empirics and the structural change perspective of development economics provide a much improved account of interprovincial variations in income levels and economic growth. [source] PROFIT TAX AND FIRM MOBILITY IN A THREE-COUNTRY MODELAUSTRALIAN ECONOMIC PAPERS, Issue 2 2010WATARU JOHDO We construct a three-country model that incorporates international relocation by imperfectly competitive firms and examine both the effects of each country's profit tax reduction on the consumption and welfare of all countries, and the incentive for the countries to decrease the profit tax. In such a model, both the terms of trade and international relocation of firms offer the key to understanding the impacts of one country's profit tax policy. In particular, we note that the relocation of firms from the other two countries is positively related to the wage incomes of the third country through a shift in labour demand, and the terms-of-trade improvement is not only positively related to the wage incomes, but also negatively related to profit incomes through a shift in world consumption demand. We show that (i) in a three-country world economy, regardless of the reduction's source, the profit tax reduction of each country leads to relocation of firms away from foreign countries toward its own economy and deteriorates the terms of trade of its economy and (ii) this becomes a ,beggar-thy-neighbour' policy in the sense that it lowers the welfare of the other foreign countries. [source] LABOUR MOBILITY AND TRANS-TASMAN CURRENCY UNION,AUSTRALIAN ECONOMIC PAPERS, Issue 1 2006ADAM CREIGHTONArticle first published online: 7 MAR 200 The prospect of a common currency for Australia and New Zealand has been canvassed by senior poli-ticians and bureaucrats, and has been the subject of academic debate. According to Mundell (1961), a high degree of internal labour mobility is a desirable feature of currency unions. This study looks at the extent to which long-term migration between Australia and New Zealand responds to output shocks. Estimated VAR models and panel Granger-causality tests demonstrate that shocks to relative per capita output have a significant and symmetrical impact on migration flows between Australia and New Zealand, and most of the impact is felt after about one year. Separating the shocks to Australia and New Zealand shows that ,pull' effects are more important than ,push' effects. Additionally, the trajectory of the Australian economy proves particularly influential for the choice of New Zealand emigrants. Although permanent migration responds intuitively to the state of the economy in Australia and New Zealand, the level of these migration flows is low in comparison to Australian inter-state migration; yet it is high in relation to any third country. [source] Comparison of methanol and acetonitrile as solvents for the separation of sertindole and its major metabolites by capillary zone electrophoresisELECTROPHORESIS, Issue 17 2005Xavier Subirats Abstract Sertindole (1-[2-[4-[5-chloro-1-(4-fluorophenyl)-1H -indol-3-yl]-1-piperidinyl]ethyl]-2-imidazolidinone), an atypical antipsychotic drug, was separated by capillary electrophoresis from its two main metabolites norsertindole and dehydrosertindole. The low solubility of the analytes in water (octanol-water partition coefficient is about 105) is overcome by the use of methanol (MeOH) and acetonitrile (ACN) as solvents for the background electrolyte (BGE). Mobilities were measured in BGEs with defined pH in a broad range. It was found that in MeOH the mobility of the analytes is mainly governed by acid,base equilibria, whereas in ACN other reactions like ion pairing and homoconjugation play a pronounced role and lead to a complex pattern of the mobility as function of the pH. However, separation can be obtained in less than 10,min in both solvent systems. [source] Air-Operable, High-Mobility Organic Transistors with Semifluorinated Side Chains and Unsubstituted Naphthalenetetracarboxylic Diimide Cores: High Mobility and Environmental and Bias Stress Stability from the Perfluorooctylpropyl Side ChainADVANCED FUNCTIONAL MATERIALS, Issue 17 2010Byung Jun Jung Abstract N,N,-bis(3-(perfluoroctyl)propyl)-1,4,5,8-naphthalenetetracarboxylic acid diimide (8,3-NTCDI) was newly synthesized, as were related fluorooctylalkyl-NTCDIs and alkyl-NTCDIs. The 8,3-NTCDI-based organic thin-film transistor (OTFT) on an octadecyltrimethoxysilane (OTS)-treated Si/SiO2 substrate shows apparent electron mobility approaching 0.7 cm2 V -1s -1 in air. The fluorooctylethyl-NTCDI (8,2-NTCDI) and fluorooctylbutyl-NTCDI (8,4-NTCDI) had significantly inferior properties even though their chemical structures are only slightly different, and nonfluorinated decyl and undecyl NTCDIs did not operate predictably in air. From atomic force microscopy, the 8,3-NTCDI active layer deposited with the substrate at 120 °C forms a polycrystalline film with grain sizes >4,m. Mobilities were stable in air for one week. After 100 days in air, the average mobility of three OTFTs decreased from 0.62 to 0.12 cm2 V -1s -1, but stabilized thereafter. The threshold voltage (VT) increased by 15 V in air, but only by 3 V under nitrogen, after one week. On/off ratios were stable in air throughout. We also investigated transistor stability to gate bias stress. The transistor on hexamethlydisilazane (HMDS) is more stable than that on OTS with mobility comparable to amorphous Si TFTs. VT shifts caused by ON (30 V) and OFF (,20 V) gate bias stress for the HMDS samples for 1 hour were 1.79 V and 1.27 V under N2, respectively, and relaxation times of 106 and 107 s were obtained using the stretched exponential model. These performances are promising for use in transparent display backplanes. [source] Orientation Control of Linear-Shaped Molecules in Vacuum-Deposited Organic Amorphous Films and Its Effect on Carrier MobilitiesADVANCED FUNCTIONAL MATERIALS, Issue 3 2010Daisuke Yokoyama Abstract The molecular orientation of linear-shaped molecules in organic amorphous films is demonstrated to be controllable by the substrate temperature. It is also shown that the molecular orientation affects the charge-transport characteristics of the films. Although linear-shaped 4,4,-bis[(N -carbazole)styryl]biphenyl molecules deposited on substrates at room temperature are horizontally oriented in amorphous films, their orientation when deposited on heated substrates with smooth surfaces becomes more random as the substrate temperature increases, even at temperatures under the glass transition temperature. Another factor dominating the orientation of the molecules deposited on heated substrates is the surface roughness of the substrate. Lower carrier mobilities are observed in films composed of randomly oriented molecules, demonstrating the significant effect of a horizontal molecular orientation on the charge-transport characteristics of organic amorphous films. [source] Transistor Paint: Environmentally Stable N -alkyldithienopyrrole and Bithiazole-Based Copolymer Thin-Film Transistors Show Reproducible High Mobilities without AnnealingADVANCED FUNCTIONAL MATERIALS, Issue 21 2009Junying Liu Abstract New solution processable 4-(2-hexyldecan)- 4H -bisthieno[2,3- d:3,,2,- b]pyrrole and 4,4,-dialkyl-2,2,-bithiazole-based copolymers (PBTzDTPs) are synthesized with excellent FET performance. These novel copolymers have considerable potential in printable electronics as they have high charge carrier mobilities, excellent air stability, good solution processibility, and no requirement for post-deposition thermal annealing, all requirements for this field of application. The thin film transistors fabricated from PBTzDTPs achieve field effect mobilities as high as 0.14,cm2 V,1 s,1 with current on/off ratios up to 106 without thermal annealing. In addition, the devices exhibit stable performance in air, showing no significant degradation over 60 days. Moreover, the polymers described here provide an excellent example of the systems in which higher mobility performance does not require higher crystalline, long-range ordered structures. Such a system appears to be particularly promising for rapid fabrication techniques, where kinetic conditions usually prevent the development of long-range order. [source] Enhancement of Carrier Mobilities of Organic Semiconductors on Sol,Gel Dielectrics: Investigations of Molecular Organization and Interfacial Chemistry EffectsADVANCED FUNCTIONAL MATERIALS, Issue 3 2009Tommy Cahyadi Abstract The dielectric-semiconductor interfacial interactions critically influence the morphology and molecular ordering of the organic semiconductor molecules, and hence have a profound influence on mobility, threshold voltage, and other vital device characteristics of organic field-effect transistors. In this study, p-channel small molecule/polymer (evaporated pentacene and spin-coated poly(3,3,;-didodecylquarterthiophene) , PQT) and n-channel fullerene derivative ({6}-1-(3-(2-thienylethoxycarbonyl)-propyl)-{5}-1-phenyl-[5,6]-C61 , TEPP-C61) show a significant enhancement in device mobilities ranging from ,6 to ,45 times higher for all classes of semiconductors deposited on sol,gel silica gate-dielectric than on pristine/octyltrichlorosilane (OTS)-treated thermally grown silica. Atomic force microscopy, synchrotron X-ray diffraction, photoluminescence/absorption, and Raman spectroscopy studies provide comprehensive evidences that sol,gel silica dielectrics-induced enhancement in both p- and n-channel organic semiconductors is attributable to better molecular ordering/packing, and hence reduced charge trapping centers due to lesser structural defects at the dielectric-semiconductor interface. [source] Magnus' Green Salt Revisited: Impact of Platinum,Platinum Interactions on Electronic Structure and Carrier Mobilities,ADVANCED MATERIALS, Issue 15 2006E.-G. Kim Magnus' green salt is the prototype of a class of organic,inorganic hybrid semiconducting materials that combine attractive charge-transport properties and processability. By using density-functional-theory methods, the electronic structure of Magnus' green salt is investigated, in particular the nature of the interplatinum interactions (see figure). In conjunction with time-of-flight measurements of the carrier mobilities, key structure,property relationships for these materials are re-established. [source] Growth and electrical properties of flash evaporated AgGaTe2 thin filmsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2006B. H. Patel Abstract Thin films have been prepared by flash evaporation technique of a stoichiometric bulk of AgGaTe2 compound in vacuum and analysed using X-ray diffraction, transmission electron microscopy, selected area diffraction and energy dispersive analysis of X-rays. The effect of substrate temperature on the structural properties , grain size, film orientation, composition, and stoichiometry of the films have been studied. It was found that the polycrystalline, stoichiometric films of AgGaTe2 can be grown in the substrate temperature range of 473K < Ts < 573K. The influence of substrate temperature (Ts) on the electrical characteristics- Resistivity, Hall Mobility, Carrier concentration of AgGaTe2 thin films were studied. The electrical resistivity was found to decrease with increase in substrate temperature up to 573K and then increases. The variation of activation energy of AgGaTe2 thin films were also investigated. The implications are discussed. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Federal University of Santa Catarina follow-up management routine for traumatized primary teeth , part 1DENTAL TRAUMATOLOGY, Issue 6 2004Mariane Cardoso Abstract,,, The objective of this study was to verify if the follow-up management routine of traumatized primary teeth set up by Federal University of Santa Catarina, which performs clinical and radiographic assessments (15 and 45 days; 4, 8 and 12 months) after the oral trauma, enabled an early diagnosis of sequelae which would indicate the need for endodontic intervention, as well as the influence a type of trauma and the child's age could have in the severity of the sequelae. In this study 52 sets of records were used of patients being seen in the last 6 months, with a total of 70 teeth that were receiving follow-up treatment. Patients returned for regular visits set up by the management routine, where clinical and radiographic examinations were performed to check for sequelae, which justified endodontic intervention. Mobility (51.2%) and crown discoloration (25.6%) were the most common sequelae found in the patient's first appointment. In the follow-up visits, replacement root resorption (22.5%) was the second most common sequela found, suggesting endodontic intervention. No significant association was found between severe sequelae, types of trauma and a child's age (,2 = 0.3, P = 0,8613). During the intervals of the follow-up visits, it was noticed that between 46 days and 8 months a higher number of sequelae were diagnosed (P < 0.05). The diagnosis of sequelae such inflammatory and replacement root resorption, which can lead to an early loss of a primary tooth, are frequent and that the interval between the follow-up visits has to be changed, suggesting the setting up of management routine 2. The study also concluded that the type of trauma and the child's age are not fundamental factors in the diagnosis of severe sequelae. [source] Rushing for Gold: Mobility and Small-Scale Mining in East AfricaDEVELOPMENT AND CHANGE, Issue 2 2009Jesper Bosse Jønsson ABSTRACT African rural dwellers have faced depressed economic prospects for several decades. Now, in a number of mineral-rich countries, multiple discoveries of gold and precious stones have attracted large numbers of prospective small-scale miners. While their ,rush' to, and activities within, mining sites are increasingly being noted, there is little analysis of miners' mobility patterns and material outcomes. In this article, on the basis of a sample survey and interviews at two gold-mining sites in Tanzania, we probe when and why miners leave one site in favour of another. Our findings indicate that movement is often ,rushed' but rarely rash. Whereas movement to the first site may be an adventure, movement to subsequent sites is calculated with knowledge of the many risks entailed. Miners spend considerable time at each site before migrating onwards. Those with the highest site mobility tend to be more affluent than the others, suggesting that movement can be rewarding for those willing to ,try their luck' with the hard work and social networking demands of mining another site. [source] Even the ,Rich' are Vulnerable: Multiple Shocks and Downward Mobility in Rural UgandaDEVELOPMENT POLICY REVIEW, Issue 1 2005Kate Bird Poverty data rarely capture processes of change, limiting our ability to understand poverty trajectories at the individual or household levels. This article uses a household survey, village-level participatory studies and indepth life-history interviews to examine people's poverty trajectories and to identify what drives and maintains chronic poverty. Composite shocks can propel previously non-poor households into severe and long-term poverty. Poverty is hard to escape, and people born into chronically poor households find few opportunities for accumulation and wealth creation. The analysis highlights the importance of poverty interrupters, including the end of conflict and the re-integration of internally displaced people, and suggests that state-led interventions would be needed to provide real opportunities to the chronically poor. [source] Intersectoral Labor Mobility and the Growth of the Service SectorECONOMETRICA, Issue 1 2006Donghoon Lee One of the most striking changes in the U.S. economy over the past 50 years has been the growth in the service sector. Between 1950 and 2000, service-sector employment grew from 57 to 75 percent of total employment. However, over this time, the real hourly wage in the service sector grew only slightly faster than in the goods sector. In this paper, we assess whether or not the essential constancy of the relative wage implies that individuals face small costs of switching sectors, and we quantify the relative importance of labor supply and demand factors in the growth of the service sector. We specify and estimate a two-sector labor market equilibrium model that allows us to address these empirical issues in a unified framework. Our estimates imply that there are large mobility costs: output in both sectors would have been double their current levels if these mobility costs had been zero. In addition, we find that demand-side factors, that is, technological change and movements in product and capital prices, were responsible for the growth of the service sector. [source] Factor mobility and fiscal policy in the EU: policy issues and analytical approachesECONOMIC POLICY, Issue 31 2000David E. Wildasin Increased integration of labour and capital markets creates significant challenges for the welfare states of modern Europe. Taxation of capital and labour that finances extensive programmes of cash and in-kind redistribution creates incentives for capital owners and workers to locate in regions where they obtain favourable fiscal treatment. Competition among countries for mobile resources constrains their ability to alter the distribution of income and may lead to reductions in the size and scope of redistributive policies. Mobility of labour and capital is imperfect, however. Recent trends indicate that labour and capital are neither perfectly mobile nor perfectly immobile, but rather adjust gradually to market conditions and economic policies. This paper presents an explicitly dynamic analysis showing that governments can achieve some redistribution when it is costly for factors of production to relocate. As the costs of factor mobility fall, however, the effectiveness of redistributive policies is more limited, and governments have weaker incentives to pursue them. Liberalized immigration policies, EU enlargement, and other steps that promote integration of the factors markets of Western Europe with those of surrounding regions thus present a challenge to policy-makers if they also wish to maintain fiscal systems with extensive redistribution. [source] Partial Ordering of Unpredictable Mobility with Welfare ImplicationsECONOMICA, Issue 299 2008DANNY BEN-SHAHAR We propose a partial ordering of ,unpredictable mobility' in the spirit of Blackwell's ordering of information structures. The proposed ordering ranks mobility matrices according to the degree to which elements in a given set are likely to move from one state to another, independently of their origin. Furthermore, for an important class of transition structures, our proposed ordering implies ordering, thus carrying significant welfare implications. Moreover, whenever it exists, our partial ordering functions as a sufficient condition for a class of renowned mobility measures and thereby generates, for a subset of transition matrices, unanimous ranking among mobility indices that are not generally consistent with one another. [source] What Lies Behind Income Mobility?ECONOMICA, Issue 282 2004Distributional Change in Belgium, Reranking, Western Germany, the USA The paper presents a decomposition of income mobility indices into two basic sources: mobility induced by a change of the income distribution shape, and mobility induced by a reordering of individuals in the income pecking order. The decomposition procedure, based on counterfactual distributions, results in a decomposition that is applicable to a broad class of mobility measures. Application to income ,movement' indices with data for Belgium, Western Germany and the USA indicates that reranking has been the major force behind income mobility. [source] Three Meanings of Intergenerational MobilityECONOMICA, Issue 272 2001Dirk Van De Gaer We axiomatize three different motivations for being concerned about intergenerational mobility: mobility as a description of movement, as an indication of equality of opportunity, and as an indication of equality of life chances. These three motivations are shown to be incompatible. None of the existing measures is acceptable as an indicator of equality of opportunity or equality of life chances. We propose two new measures of intergenerational mobility which more adequately reflect these concerns. [source] Measuring Social Mobility as UnpredictabilityECONOMICA, Issue 269 2001Simon C. Parker By associating mobility with the unpredictability of social states, new measures of social mobility may be constructed. We propose a family of three state-by-state and aggregate (scalar) predictability measures. The first set of measures is based on the transition matrix. The second uses a sampling approach and permits statistical testing of the hypothesis of perfect mobility, providing a new justification for the use of the ,2 statistic. The third satisfies the demanding criterion of ,period consistency'. An empirical example demonstrates the usefulness of the new measures to complement existing ones in the literature. [source] Caught in a Trap?ECONOMICA, Issue 268 2000Wage Mobility in Great Britain: 197 In this paper I study wage mobility in Great Britain using the New Earnings Surveys of 1975,94 and the British Household Panel Surveys of 1991,94. Measuring mobility in terms of decile transition matrices, I find a considerable degree of immobility within the wage distribution from one year to the next. Mobility is higher when measured over longer time periods. Those in lower deciles in the wage distribution are much more likely to exit into unemployment and non-employment. Measuring mobility by studying changes in individuals' actual percentile rankings in the wage distribution, I find evidence that short-run mobility rates have fallen since the late 1970s. This has potentially important welfare implications, given the rise in cross-section earnings inequality observed over the last two decades. [source] Separation and recovery of intact gold-virus complex by agarose electrophoresis and electroelution: Application to the purification of cowpea mosaic virus and colloidal gold complexELECTROPHORESIS, Issue 17 2004Carissa M. Soto Abstract Colloidal gold has been coupled to a mutant cowpea mosaic virus (CPMV), which contains 60 cysteine residues on the surface. A purification process was developed to separate the gold-containing viral nanoblocks (VNBs) from the free gold. Agarose electrophoresis was utilized to separate the mixture followed by electroelution of the desired sample to recover the intact virus. Mobility of Au-VNB and free colloidal gold was facilitated by the addition of thioctic acid (TA). 30% of the gold-containing virus was recovered after electroelution as determined by absorbance measurements. Histogram analysis of transmission electron microscopy (TEM) images demonstrated the efficient separation of gold-containing virus from free gold. TEM and scanning electron microscopy (SEM) images indicated that the virus was recovered intact. Monodisperse spherical particles of nominal size of 45 nm were observed under SEM. [source] Mobility and potential toxicity of sediment-bound metals in a tidal estuaryENVIRONMENTAL TOXICOLOGY, Issue 4 2005O. Geffard Abstract Sediment toxicity in the Gironde Estuary, France, a site contaminated by such trace metals as Cd, Cu, and Zn, was examined monthly from March to October 1997, using concurrently geochemical procedures to assess the mobility of contaminants and ecotoxicity tests with invertebrate larvae (the oyster Crassostrea gigas, the sea urchin Paracentrotus lividus, and the copepod Tigriopus brevicornis). Higher mobility of Cd than of Cu and Zn was shown by desorption tests. Both the gross concentrations of Cu and Zn in the sediment and the mobility of these metals showed a temporal evolution, and changes in the toxicity of the sediment to invertebrate larvae generally were observed concomitantly. Little damage was registered in the spring, and greater damage was found in the summer and fall. Positive correlations were shown between mortality in copepods or abnormalities in oyster larvae with the quantities of metals remobilized from sediment at pH 4. On the contrary, no clear temporal trend was shown for total PAH levels in sediment. These correlations and previous toxicological data suggest that sediment-bound metals, particularly Cu and Zn, possibly play a role in biological responses. © 2005 Wiley Periodicals, Inc. Environ Toxicol 20: 407,417, 2005. [source] Learning by Leaving , Towards a Pedagogy for Transnational Mobility in the Context of Vocational Education and Training (VET)EUROPEAN JOURNAL OF EDUCATION, Issue 4 2001Søren Kristensen First page of article [source] Positively Charged Material Surfaces Generated by Plasma Polymerized Allylamine Enhance Vinculin Mobility in Vital Human Osteoblastss,ADVANCED ENGINEERING MATERIALS, Issue 8 2010Henrike Rebl Abstract Several studies suggest that the modification of an implant surface by chemical means plays an important role in bone tissue engineering. Previously we have shown that osteoblast cell adhesion and spreading can strongly be increased by a positively charged surface. Cell adhesion and migration are two vital processes that are completely dependent on coordinated formation of focal adhesions. Changes in the organization of the actin cytoskeleton and the focal adhesions are essential for numerous cellular processes including cell motility and tissue morphogenesis. We examined the mobility of the cytoskeletally associated protein vinculin on functionalized surfaces using plasma polymerized allylamine (PPAAm), a homogenous plasma polymer layer with randomly distributed amino groups. In living, GFP,vinculin transfected osteoblastic cells we determined a significant increase in vinculin mobility and vinculin contact length on PPAAm compared to collagen I coated surfaces during the initial adhesion phase. We suggest that positive charges control the cell physiology which seems to be dominant over the integrin receptor binding to collagen I. The results emphasize the role of the surface charge for the design of artificial scaffolds in bone repair. [source] Air-Operable, High-Mobility Organic Transistors with Semifluorinated Side Chains and Unsubstituted Naphthalenetetracarboxylic Diimide Cores: High Mobility and Environmental and Bias Stress Stability from the Perfluorooctylpropyl Side ChainADVANCED FUNCTIONAL MATERIALS, Issue 17 2010Byung Jun Jung Abstract N,N,-bis(3-(perfluoroctyl)propyl)-1,4,5,8-naphthalenetetracarboxylic acid diimide (8,3-NTCDI) was newly synthesized, as were related fluorooctylalkyl-NTCDIs and alkyl-NTCDIs. The 8,3-NTCDI-based organic thin-film transistor (OTFT) on an octadecyltrimethoxysilane (OTS)-treated Si/SiO2 substrate shows apparent electron mobility approaching 0.7 cm2 V -1s -1 in air. The fluorooctylethyl-NTCDI (8,2-NTCDI) and fluorooctylbutyl-NTCDI (8,4-NTCDI) had significantly inferior properties even though their chemical structures are only slightly different, and nonfluorinated decyl and undecyl NTCDIs did not operate predictably in air. From atomic force microscopy, the 8,3-NTCDI active layer deposited with the substrate at 120 °C forms a polycrystalline film with grain sizes >4,m. Mobilities were stable in air for one week. After 100 days in air, the average mobility of three OTFTs decreased from 0.62 to 0.12 cm2 V -1s -1, but stabilized thereafter. The threshold voltage (VT) increased by 15 V in air, but only by 3 V under nitrogen, after one week. On/off ratios were stable in air throughout. We also investigated transistor stability to gate bias stress. The transistor on hexamethlydisilazane (HMDS) is more stable than that on OTS with mobility comparable to amorphous Si TFTs. VT shifts caused by ON (30 V) and OFF (,20 V) gate bias stress for the HMDS samples for 1 hour were 1.79 V and 1.27 V under N2, respectively, and relaxation times of 106 and 107 s were obtained using the stretched exponential model. These performances are promising for use in transparent display backplanes. 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