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Marginal
Kinds of Marginal Terms modified by Marginal Selected AbstractsDevice Closure of a Secundum Atrial Septal Defect in a 4-Month-Old Infant with a Marginal Left Ventricle Following Coarctation RepairCONGENITAL HEART DISEASE, Issue 6 2007Emilie Jean-St-Michel BSc ABSTRACT A male infant presented at birth with severe coarctation of the aorta and marginal left ventricular and mitral valve dimensions associated with a large secundum atrial septal defect. Following successful arch repair, the left ventricle remained small with preferential left-to-right atrial shunting and a dilated right ventricle. Clinically, the infant continued with tachypnea, poor feeding, and failure to thrive. At 4 months of age, the defect was closed with an Amplatzer Atrial Septal Occluder which resulted in immediate left ventricular cavity enlargement and clinical improvement. [source] Flattening the Effective Marginal Tax Rate Structure in Australia: Policy Simulations Using the Melbourne Institute Tax and Transfer SimulatorTHE AUSTRALIAN ECONOMIC REVIEW, Issue 2 2003John Creedy This article uses the Melbourne Institute Tax and Transfer Simulator to examine the effects of a reduction in the means-tested benefit taper, or withdrawal, rates in Australia to 30 per cent. That is, all taper rates of 50 per cent and 70 per cent in the March 1998 benefit system are reduced to 30 per cent, while leaving all basic benefit levels unchanged. This change is therefore expected to ,flatten' the tax structure by reducing the high marginal tax rates applying to those with relatively low incomes and increasing the marginal tax rates of medium incomes. Simulations in which all individuals are assumed to remain at their pre-reform labour supply levels are compared with behavioural simulations in which the majority of individuals are free to adjust the number of hours worked. The results reflect only the supply side of the labour market. The database used is the 1997-98 Survey of Income and Housing Costs, so that weekly incomes are based on the financial year 1997-98. The comparison shows that, for sole parents, accounting for behavioural effects of the reform results in a lower estimated expenditure for government, whereas for couples, accounting for behavioural effects results in a higher estimated expenditure. [source] Beyond Being Marginal: Gender and International Relations in BritainBRITISH JOURNAL OF POLITICS & INTERNATIONAL RELATIONS, Issue 2 2007Judith Squires In this introduction, we situate ,gender and international relations in Britain'. We discuss our understandings of gender, I/international R/relations and GIR. In the second section we discuss the relationship of feminist to gendered IR, arguing that while intimately related, they are nonetheless not synonymous. We turn in the third section to a critical discussion of feminist IR's tendency to see itself as marginal to mainstream IR, a move that contributes to the marginalisation it laments. In the fourth section we compare the development of GIR with gender in Politics, which has been less concerned from the outset with issues of marginality. In the final section we argue that GIR has come into its own, introducing the articles in this issue as instances of self-assured gendered analyses of ,things international'. [source] Reduced change blindness suggests enhanced attention to detail in individuals with autismTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 3 2009Hayley Smith Background:, The phenomenon of change blindness illustrates that a limited number of items within the visual scene are attended to at any one time. It has been suggested that individuals with autism focus attention on less contextually relevant aspects of the visual scene, show superior perceptual discrimination and notice details which are often ignored by typical observers. Methods:, In this study we investigated change blindness in autism by asking participants to detect continuity errors deliberately introduced into a short film. Whether the continuity errors involved central/marginal or social/non-social aspects of the visual scene was varied. Thirty adolescent participants, 15 with autistic spectrum disorder (ASD) and 15 typically developing (TD) controls participated. Results:, The participants with ASD detected significantly more errors than the TD participants. Both groups identified more errors involving central rather than marginal aspects of the scene, although this effect was larger in the TD participants. There was no difference in the number of social or non-social errors detected by either group of participants. Conclusion:, In line with previous data suggesting an abnormally broad attentional spotlight and enhanced perceptual function in individuals with ASD, the results of this study suggest enhanced awareness of the visual scene in ASD. The results of this study could reflect superior top-down control of visual search in autism, enhanced perceptual function, or inefficient filtering of visual information in ASD. [source] Device Closure of a Secundum Atrial Septal Defect in a 4-Month-Old Infant with a Marginal Left Ventricle Following Coarctation RepairCONGENITAL HEART DISEASE, Issue 6 2007Emilie Jean-St-Michel BSc ABSTRACT A male infant presented at birth with severe coarctation of the aorta and marginal left ventricular and mitral valve dimensions associated with a large secundum atrial septal defect. Following successful arch repair, the left ventricle remained small with preferential left-to-right atrial shunting and a dilated right ventricle. Clinically, the infant continued with tachypnea, poor feeding, and failure to thrive. At 4 months of age, the defect was closed with an Amplatzer Atrial Septal Occluder which resulted in immediate left ventricular cavity enlargement and clinical improvement. [source] Relocating Participation within a Radical Politics of DevelopmentDEVELOPMENT AND CHANGE, Issue 2 2005Sam Hickey In response to (and in sympathy with) many of the critical points that have been lodged against participatory approaches to development and governance within international development, this article seeks to relocate participation within a radical politics of development. We argue that participation needs to be theoretically and strategically informed by a radical notion of ,citizenship', and be located within the ,critical modernist' approach to development. Using empirical evidence drawn from a range of contemporary approaches to participation, the article shows that participatory approaches are most likely to succeed: (i) where they are pursued as part of a wider radical political project; (ii) where they are aimed specifically at securing citizenship rights and participation for marginal and subordinate groups; and (iii) when they seek to engage with development as an underlying process of social change rather than in the form of discrete technocratic interventions , although we do not use these findings to argue against using participatory methods where these conditions are not met. Finally, we consider the implications of this relocation for participation in both theoretical and strategic terms. [source] Membrane dynamics of cleavage furrow closure in Xenopus laevisDEVELOPMENTAL DYNAMICS, Issue 3 2008Michael V. Danilchik Abstract Epithelial membrane polarity develops early in Xenopus development, with membrane inserted along the earliest cleavage furrows by means of localized exocytosis. The added surface constitutes a new basolateral domain important for early morphogenesis. This basolateral surface becomes isolated from the outside by furrow closure, a zippering of adjacent apical,basolateral margins. Time-lapse microscopy of membrane-labeled embryos revealed two distinct kinds of protrusive activity in furrow closure. Early in furrowing, protrusive activity was associated with purse-string contractility along the apical,basolateral margins. Later in furrow progression, a basolateral protrusive zone developed entirely within the new membrane domain, with long motile filopodia extending in contractile bands from the exposed surfaces. Filopodia interacting with opposing cell surfaces across the cleavage furrow appeared to mediate blastomere,blastomere adhesion, contact spreading and lamellipodial protrusion. Interference with these dynamic activities prevented furrow closure, indicating a basic role for both marginal and basolateral protrusive activities in early embryogenesis. Developmental Dynamics 237:565,579, 2008. © 2008 Wiley-Liss, Inc. [source] Effects of a natural extract of (,)-hydroxycitric acid (HCA-SX) and a combination of HCA-SX plus niacin-bound chromium and Gymnema sylvestre extract on weight lossDIABETES OBESITY & METABOLISM, Issue 3 2004H. G. Preuss Aim:, The efficacy of optimal doses of highly bioavailable (,)-hydroxycitric acid (HCA-SX) alone and in combination with niacin-bound chromium (NBC) and a standardized Gymnema sylvestre extract (GSE) on weight loss in moderately obese subjects was evaluated by monitoring changes in body weight, body mass index (BMI), appetite, lipid profiles, serum leptin and excretion of urinary fat metabolites. HCA-SX has been shown to reduce appetite, inhibit fat synthesis and decrease body weight without stimulating the central nervous system. NBC has demonstrated its ability to maintain healthy insulin levels, while GSE has been shown to regulate weight loss and blood sugar levels. Methods:, A randomized, double-blind, placebo-controlled human study was conducted in Elluru, India for 8 weeks in 60 moderately obese subjects (ages 21,50, BMI >26 kg/m2). Subjects were randomly divided into three groups. Group A was administered HCA-SX 4667 mg, group B was administered a combination of HCA-SX 4667 mg, NBC 4 mg and GSE 400 mg, while group C was given placebo daily in three equally divided doses 30,60 min before meals. All subjects received a 2000 kcal diet/day and participated in supervised walking. Results:, At the end of 8 weeks, body weight and BMI decreased by 5,6% in both groups A and B. Food intake, total cholesterol, low-density lipoproteins, triglycerides and serum leptin levels were significantly reduced in both groups, while high-density lipoprotein levels and excretion of urinary fat metabolites increased in both groups. A marginal or non-significant effect was observed in all parameters in group C. Conclusion:, The present study shows that optimal doses of HCA-SX and, to a greater degree, the combination of HCA-SX, NBC and GSE can serve as an effective and safe weight-loss formula that can facilitate a reduction in excess body weight and BMI, while promoting healthy blood lipid levels. [source] Changing household responses to drought in Tharaka, Kenya: vulnerability, persistence and challengeDISASTERS, Issue 2 2008Thomas A. Smucker Drought is a recurring challenge to the livelihoods of those living in Tharaka District, Kenya, situated in the semi-arid zone to the east of Mount Kenya, from the lowest slopes of the mountain to the banks of the Tana River. This part of Kenya has been marginal to the economic and political life of Kenya from the colonial period until the present day. A study of more than 30 years of change in how people in Tharaka cope with drought reveals resilience in the face of major macro-level transformations, which include privatisation of landownership, population growth, political decentralisation, increased conflict over natural resources, different market conditions, and environmental shifts. However, the study also shows troubling signs of increased use of drought responses that are incompatible with long-term agrarian livelihoods. Government policy needs to address the challenge of drought under these new macro conditions if sustainable human development is to be achieved. [source] Conflict, trade and the medium-term future of food security in SudanDISASTERS, Issue 2007David Keen Recent economic growth and the Comprehensive Peace Agreement (CPA) have both been seen as grounds for optimism about the future of food security in Sudan. However, solving the North- South conflict (if indeed it is solved) does not resolve conflicts within either the North or the South and may even encourage a variety of conflicts. The classic neoliberal prescription of peace, growth and foreign investment may deepen (and obscure) the needs and grievances of those who have historically been left behind in a dysfunctional development process. Historically, some of those marginalised by patterns of development in Sudan have chosen to rebel, while others have had their grievances diverted against those even more marginal than themselves. Dysfunctional and violent processes of development must be reversed. They cannot be adequately compensated for-but may be legitimised-by attempts to use food aid as a ,safety net'. Meanwhile, those who benefited from war may have incentives to derail the peace. [source] Zimbabwe's Child Supplementary Feeding Programme: A Re,assessment Using Household Survey DataDISASTERS, Issue 3 2002Lauchlan T. Munro In 1992,3 and 1995,6, Zimbabwe used a Child Supplementary Feeding Programme (CSFP) to combat child malnutrition during drought,induced emergencies. Previous evaluations of the CSFP relied on routine administrative data and key informant interviews and made only cursory use of available household survey data. These evaluations concluded that the CSFP was effective in preventing an increase in malnutrition among children under five, especially in 1992,3. The more,detailed analysis of household surveys provided in this article suggests that CSFP coverage was generally patchy and disappointingly low, especially in 1995,6. There is little evidence that children from poor or nutritionally vulnerable households got preferential access to supplementary feeding. The CSFP failed to feed many malnourished and nutritionally vulnerable children even in areas where the programme was operating. Household survey evidence suggests that the CSFP's impact on nutritional status was likely marginal, especially in 1995,6. [source] Phenotypic plasticity, polymorphism and phylogeny within placodermsACTA ZOOLOGICA, Issue 2009K. Trinajstic Abstract Intraspecies variation, polymorphism and asymmetric traits are observed within two families of Arthrodira, the Incisoscutidae and Camuropiscidae, from the Gogo Formation in northern Western Australia. Individual plates of the head and trunk shield show considerable variation between individuals. Plates that show the greatest degree polymorphic traits are the rostral (R), marginal (M), submarginal (SM), preorbital (PrO), anterior dorsolateral, anterior median ventral (AMV) and posterior ventrolateral (PVL) plates. The paths of the sensory line canals are the most variable feature and the dermal plates of the cheek show the greatest asymmetry. It is apparent that if anatomical data in arthrodires are to be interpreted with greater precision, detailed knowledge of intraspecies variation, polymorphic and asymmetric traits is essential. How these variables are treated in cladistic analysis is also critical. Here multistate characters were coded differently in five discrete analyses, each analysis yielding a different number of trees and relationships. It was concluded that including and coding for multistate characters gave the most robust tree. In addition, further morphological characters from a new specimen of Gogosteus sarahae Long (1994) indicates many of the characters used to separate this genus from Incisoscutum are inconsistent and so it is here considered that the genus Gogosteus is a junior synonym of Incisoscutum. [source] Mixed biodiversity benefits of agri-environment schemes in five European countriesECOLOGY LETTERS, Issue 3 2006D. Kleijn Abstract Agri-environment schemes are an increasingly important tool for the maintenance and restoration of farmland biodiversity in Europe but their ecological effects are poorly known. Scheme design is partly based on non-ecological considerations and poses important restrictions on evaluation studies. We describe a robust approach to evaluate agri-environment schemes and use it to evaluate the biodiversity effects of agri-environment schemes in five European countries. We compared species density of vascular plants, birds, bees, grasshoppers and crickets, and spiders on 202 paired fields, one with an agri-environment scheme, the other conventionally managed. In all countries, agri-environment schemes had marginal to moderately positive effects on biodiversity. However, uncommon species benefited in only two of five countries and species listed in Red Data Books rarely benefited from agri-environment schemes. Scheme objectives may need to differentiate between biodiversity of common species that can be enhanced with relatively simple modifications in farming practices and diversity or abundance of endangered species which require more elaborate conservation measures. [source] Patents and R&D as Real OptionsECONOMIC NOTES, Issue 1 2004Eduardo S. Schwartz This article develops and implements a simulation approach to value patents and patent-protected R&D projects based on the Real Options approach. It takes into account uncertainty in the cost-to-completion of the project, uncertainty in the cash flows to be generated from the project, and the possibility of catastrophic events that could put an end to the effort before it is completed. It also allows for the possibility of abandoning the project when costs turn out to be larger than expected or when estimated cash flows turn out to be smaller than anticipated. This abandonment option represents a very substantial part of the project's value when the project is marginal or/and when uncertainty is large. The model presented can be used to evaluate the effects of regulation on the cost of innovation and the amount on innovative output. The main focus of the article is the pharmaceutical industry. The framework, however, applies just as well to other research-intensive industries such as software or hardware development. (J.E.L.:G31, O22, O32). [source] Association of tobacco dependence and quit attempt duration with Rasch-modeled withdrawal sensitivity using retrospective measuresADDICTION, Issue 6 2009Harold S. Javitz ABSTRACT Aim To examine whether Rasch modeling would yield a unidimensional withdrawal sensitivity measure correlating with factors associated with successful smoking cessation. Design The psychometric Rasch modeling approach was applied to estimate an underlying latent construct (withdrawal sensitivity) in retrospective responses from 1644 smokers who reported quitting for 3 or more months at least once. Setting Web-based, passcode-controlled self-administered computerized questionnaire. Participants Randomly selected convenience sample of 1644 adult members of an e-mail invitation-only web panel drawn from consumer databases. Measurements Lifetime Tobacco Use Questionnaire, assessing tobacco use across the life-span, including demographics and respondent ratings of the severity of withdrawal symptoms experienced in respondents' first and most recent quit attempts lasting 3 or more months. Findings Rasch-modeled withdrawal sensitivity was generally unidimensional and was associated with longer periods of smoking cessation. One latent variable accounted for 74% of the variability in symptom scores. Rasch modeling with a single latent factor fitted withdrawal symptoms well, except for increased appetite, for which the fit was marginal. Demographic variables of education, gender and ethnicity were not related to changes in sensitivity. Correlates of greater withdrawal sensitivity in cessation attempts of at least 3 months included younger age at first quit attempt and indicators of tobacco dependence. Conclusion The relationship between tobacco dependence symptoms and Rasch-model withdrawal sensitivity defines further the relationship between sensitivity and dependence. The findings demonstrate the utility of modeling to create an individual-specific sensitivity measure as a tool for exploring the relationships among sensitivity, dependence and cessation. [source] Urinary concentrations of bisphenol A in relation to biomarkers of sensitivity and effect and endocrine-related health effectsENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 8 2006Mihi Yang Abstract The impact of endocrine-disrupting chemicals (EDCs) on human health is not yet clear because of difficulties in ascertaining their biological effects. In the present study, we evaluated exposure to the EDC, bisphenol A (BPA), in 172 Koreans in relation to biomarkers of susceptibility and effect. The subjects completed questionnaires, which documented occupation, education, lifestyle factors, potential sources of BPA-exposure, and the occurrence of self-diagnosed endocrine disorders. None of the subjects were occupationallay exposed to BPA; however, urinary levels of conjugated BPA, determined by HPLC/FD, ranged from 0.03,62.4 ,g/l (median, 7.86). The frequencies of potential susceptibility biomarkers, the UGT1A6-Arg184Ser and the SULT1A1- Arg213His polymorphisms, were not associated with urinary BPA levels, either as single genes or in combination. Indirect effects of BPA exposure on the susceptibility to mutagens were evaluated by comparing urinary BPA concentrations with MNNG-induced sister-chromatid exchange (SCE) in lymphocytes cultured from the subjects. BPA exposure showed marginal or significant associations with theSCEs induced by the low doses of MNNG (0,0.4 mM). However, there was no overall association between urinary BPA levels and MNNG-induced frequency at doses ranging from 0.2,0.6 mM. Finally, we did not detect an association between urinary BPA concentration and endocrine-related disorders. Even though we were unable to find a strong association between BPA exposure and a biological response, possibly because of the limited number of subjects, we observed that most of the subjects were exposed to BPA. Therefore, continuous biological monitoring of BPA is a prudent measure to prevent possible BPA-related health risks. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] Lead accumulation in feathers of nestling black-crowned night herons (Nycticorax nycticorax) experimentally treated in the fieldENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2003Nancy H. Golden Abstract Although lead can attain high concentrations in feathers, interpretation of the biological significance of this phenomenon is difficult. As part of an effort to develop and validate noninvasive methods to monitor contaminant exposure in free-ranging birds, lead uptake by feathers of nestling black-crowned night herons (Nycticorax nycticorax) was evaluated in a controlled exposure study. Four- to 6-d-old heron nestlings (one/nest) at Chincoteague Bay, Virginia (USA), received a single intraperitoneal injection of dosing vehicle (control, n = 7) or a dose of lead nitrate in water (0.01, 0.05, or 0.25 mg Pb/g body wt of nestling; n = 6 or 7/dose) chosen to yield feather lead concentrations found at low- to moderately polluted sites. Nestlings were euthanized at 15 d of age. Lead accumulation in feathers was associated with concentrations in bone, kidney, and liver (r = 0.32,0.74, p < 0.02) but exhibited only modest dose dependence. Blood delta-aminolevulinic acid dehydratase activity was inhibited by lead, although effects on other biochemical endpoints were marginal. Tarsus growth rate was inversely related to feather lead concentration. Culmen growth rate was depressed in nestlings treated with the highest dose of lead but not correlated with feather lead concentration. These findings provide evidence that feathers of nestling herons are a sensitive indicator of lead exposure and have potential application for the extrapolation of lead concentrations in other tissues and the estimation of environmental lead exposure in birds. [source] Assessment of short-term association between health outcomes and ozone concentrations using a Markov regression modelENVIRONMETRICS, Issue 3 2003Abdelkrim Zeghnoun Abstract Longitudinal binary data are often used in panel studies where short-term associations between air pollutants and respiratory health outcomes are investigated. A Markov regression model in which the transition probabilities depend on the covariates, as well as the past responses, was used to study the short-term association between daily ozone (O3) concentrations and respiratory health outcomes in a panel of schoolchildren in Armentičres, Northern France. The results suggest that there was a small but statistically significant association between O3 and children's cough episodes. A 10,,g/m3 increase in O3 concentrations was associated with a 13.9,% increase in cough symptoms (CI,95%,=,1.2,28.1%). The use of a Markov regression model can be useful as it permits one to address easily both the regression objective and the stochastic dependence between successive observations. However, it is important to verify the sensitivity of the Markov regression parameters to the time-dependence structure. In this study, it was found that, although what happened on the previous day was a strong predictor of what happened on the current day, this did not contradict the O3 -respiratory symptom associations. Compared to the Markov regression model, the signs of the parameter estimates of marginal and random-intercept models remain the same. The magnitudes of the O3 effects were also essentially the same in the three models, whose confidence intervals overlapped. Copyright © 2003 John Wiley & Sons, Ltd. [source] N -methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (MBDB): its properties and possible risksADDICTION BIOLOGY, Issue 3 2000L. A. G. J. M. Van Aerts MBDB (N -methyl-1-(1,3-benzodioxol-5-yl)-2-aminobutane) is the ,-ethyl homologue of MDMA (3,4-methylenedioxy-N-methylamphetamine). MBDB is metabolized and excreted similarly to MDMA: presumably, the majority of oral MBDB is excreted in urine unmetabolized. The main metabolic routes in man are thought to be O-dealkylation and subsequent methylation, sulphation and glucuronidation of the newly formed hydroxy groups. The major acute neuropharmacological effects of MBDB in the rat are an increase in serotonin release in the brain and an inhibition of serotonin and noradrenaline re-uptake. These effects compare well with those of MDMA, although the latter is more potent. MBDB may also slightly increase dopamine release and inhibit dopamine re-uptake, but to a lesser extent than MDMA. This is important, as dopamine release has been implicated in the reinforcing qualities of substances such as cocaine and amphetamine. The neuroendocrine effects of MBDB resemble those of MDMA. Both substances increase plasma ACTH, corticosterone, prolactin and renin. The neurophysiological effects of MBDB are characterized by a decrease in electrical activity throughout the brain, most notably in the alpha 2 and delta frequency bands. In contrast, hallucinogens increase the activity in the alpha 1 band, especially in the corpus striatum. In drug discrimination tests in the rat, MBDB, like MDMA, can be distinguished clearly from both stimulants and hallucinogens. The class of substances to which MBDB belongs may be named entactogens. MBDB dose-dependently increases locomotor activity and decreases exploratory behaviour in the rat and causes distress vocalization and wing extension in the newly hatched chicken. The rewarding properties of MBDB appear to be smaller than those of MDMA, as suggested by a 2.5 times weaker potency in the conditioned place preference test in rats. The main subjective effects of MBDB in man are a pleasant state of introspection, with greatly facilitated interpersonal communication and a pronounced sense of empathy and compassion between subjects. In this respect, MBDB again resembles MDMA. However, there are also differences. MBDB has a slower and more gentle onset of action than MDMA, produces less euphoria and has less stimulant properties. The few toxicological data available suggest that MBDB may cause serotonergic deficits in the brain, although the potency of MBDB to cause this neurotoxic effect is smaller than that of MDMA. Severe acute reactions in man as have been reported for MDMA have not been published for MBDB. The dependence potential of MBDB appears to be small, probably even smaller than that of MDMA. MBDB has been available at least since 1994 but its position on the synthetic drugs market is marginal. Subjective reports indicate that MBDB is less popular among users than MDMA. The reason may be that MBDB produces less euphoria than MDMA. Another possible explanation is that MBDB largely lacks the stimulant properties of MDMA. We calculated a margin of safety with a method similar to one used in the risk assessment of pharmaceuticals. The results suggest that MBDB is three times less likely to cause serotonergic brain deficits than MDMA. However, it should be noted that for both substances the margin of safety is less than one, indicating that the risk of neurotoxicity is not negligible. In animals, serotonergic brain deficits after exposure to MDMA have been linked to the degeneration of serotonergic nerve terminals. [source] Peripheral axotomy induces only very limited sprouting of coarse myelinated afferents into inner lamina II of rat spinal cordEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2002Lan Bao Abstract Peripheral axotomy-induced sprouting of thick myelinated afferents (A-fibers) from laminae III,IV into laminae I,II of the spinal cord is a well-established hypothesis for the structural basis of neuropathic pain. However, we show here that the cholera toxin B subunit (CTB), a neuronal tracer used to demonstrate the sprouting of A-fibers in several earlier studies, also labels unmyelinated afferents (C-fibers) in lamina II and thin myelinated afferents in lamina I, when applied after peripheral nerve transection. The lamina II afferents also contained vasoactive intestinal polypeptide and galanin, two neuropeptides mainly expressed in small dorsal root ganglion (DRG) neurons and C-fibers. In an attempt to label large DRG neurons and A-fibers selectively, CTB was applied four days before axotomy (pre-injury-labelling), and sprouting was monitored after axotomy. We found that only a small number of A-fibers sprouted into inner lamina II, a region normally innervated by C-fibers, but not into outer lamina II or lamina I. Such sprouts made synaptic contact with dendrites in inner lamina II. Neuropeptide Y (NPY) was found in these sprouts in inner lamina II, an area very rich in Y1 receptor-positive processes. These results suggest that axotomy-induced sprouting from deeper to superficial layers is much less pronounced than previously assumed, in fact it is only marginal. This limited reorganization involves large NPY immunoreactive DRG neurons sprouting into the Y1 receptor-rich inner lamina II. Even if quantitatively small, it cannot be excluded that this represents a functional circuitry involved in neuropathic pain. [source] Clinical fit of all-ceramic three-unit fixed partial dentures, generated with three different CAD/CAM systemsEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2005Sven Reich In this study, the hypothesis was tested that the marginal and internal fit of CAD/CAM fabricated all-ceramic three-unit fixed partial dentures (FPDs) can be as good as in metal,ceramic FPDs. Twenty-four all-ceramic FPDs were fabricated and randomly subdivided into three equally sized groups. Eight frameworks were fabricated using the Digident CAD/CAM system (DIGI), another eight frameworks using the Cerec Inlab system (INLA). Vita Inceram Zirkonia blanks were used for both groups. In a third group frameworks were milled from yttrium-stabilized Zirconium blanks using the Lava system (LAVA). All frameworks were layered with ceramic veneering material. In addition, six three-unit metal-ceramic FPDs served as control group. All FPDs were evaluated using a replica technique with a light body silicone stabilized with a heavy body material. The replica samples were examined under microscope. The medians of marginal gaps were 75 µm for DIGI, 65 µm for LAVA and INLA and 54 µm for the conventional FPDs. Only the DIGI data differed significantly from those of the conventional FPDs. Within the limits of this study, the results suggest that the accuracy of CAD/CAM generated three-unit FPDs is satisfactory for clinical use. [source] In vitro evaluation of marginal and internal adaptation after occlusal stressing of indirect class II composite restorations with different resinous basesEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2003Didier Dietschi Composite inlays are indicated for large cavities, which frequently extend cervically into dentin. The purpose of this study was to compare in vitro the marginal and internal adaptation of class II fine hybrid composite inlays (Herculite, Kerr) made with or without composite bases, having different physical properties. Freshly extracted human molars were used for this study. The base extended up to the cervical margins on both sides and was made from Revolution (Kerr), Tetric flow (Vivadent), Dyract (Detrey-Dentsply) or Prodigy (Kerr), respectively. Before, during and after mechanical loading (1 million cycles, with a force varying from 50 to 100 N), the proximal margins of the inlay were assessed by scanning electron microscopy. Experimental data were analysed using non-parametric tests. The final percentages of marginal tooth fracture varied from 30.7% (no base) to 37.6% (Dyract). In dentin, percentages of marginal opening varied from 9.2% (Tetric Flow) to 30.1% (Prodigy), however, without significant difference between base products. Mean values of opened internal interface with dentin varied from 11.06% (Tetric Flow) to 28.15% (Prodigy). The present results regarding dentin adaptation confirmed that the physical properties of a base can influence composite inlay adaptation and that the medium-rigid flowable composite Tetric Flow is a potential material to displace, in a coronal position, proximal margins underneath composite inlays. [source] Identification of RNase HII from psychrotrophic bacterium, Shewanella sp.FEBS JOURNAL, Issue 10 2006SIB1 as a high-activity type RNase H The gene encoding RNase HII from the psychrotrophic bacterium, Shewanella sp. SIB1 was cloned, overexpressed in Escherichia coli, and the recombinant protein was purified and biochemically characterized. SIB1 RNase HII is a monomeric protein with 212 amino acid residues and shows an amino acid sequence identity of 64% to E. coli RNase HII. The enzymatic properties of SIB1 RNase HII, such as metal ion preference, pH optimum, and cleavage mode of substrate, were similar to those of E. coli RNase HII. SIB1 RNase HII was less stable than E. coli RNase HII, but the difference was marginal. The half-lives of SIB1 and E. coli RNases HII at 30 °C were ,,30 and 45 min, respectively. The midpoint of the urea denaturation curve and optimum temperature of SIB1 RNase HII were lower than those of E. coli RNase HII by ,,0.2 m and ,,5 °C, respectively. However, SIB1 RNase HII was much more active than E. coli RNase HII at all temperatures studied. The specific activity of SIB1 RNase HII at 30 °C was 20 times that of E. coli RNase HII. Because SIB1 RNase HII was also much more active than SIB1 RNase HI, RNases HI and HII represent low- and high-activity type RNases H, respectively, in SIB1. In contrast, RNases HI and HII represent high- and low-activity type RNases H, respectively, in E. coli. We propose that bacterial cells usually contain low- and high-activity type RNases H, but these types are not correlated with RNase H families. [source] The effect of HAMP domains on class IIIb adenylyl cyclases from Mycobacterium tuberculosisFEBS JOURNAL, Issue 12 2004Jürgen U. Linder The genes Rv1318c, Rv1319c, Rv1320c and Rv3645 of Mycobacterium tuberculosis are predicted to code for four out of 15 adenylyl cyclases in this pathogen. The proteins consist of a membrane anchor, a HAMP region and a class IIIb adenylyl cyclase catalytic domain. Expression and purification of the isolated catalytic domains yielded adenylyl cyclase activity for all four recombinant proteins. Expression of the HAMP region fused to the catalytic domain increased activity in Rv3645 21-fold and slightly reduced activity in Rv1319c by 70%, demonstrating isoform-specific effects of the HAMP domains. Point mutations were generated to remove predicted hydrophobic protein surfaces in the HAMP domains. The mutations further stimulated activity in Rv3645 eight-fold, whereas the effect on Rv1319c was marginal. Thus HAMP domains can act directly as modulators of adenylyl cyclase activity. The modulatory properties of the HAMP domains were confirmed by swapping them between Rv1319c and Rv3645. The data indicate that in the mycobacterial adenylyl cyclases the HAMP domains do not display a uniform regulatory input but instead each form a distinct signaling unit with its adjoining catalytic domain. [source] Binding of rat brain hexokinase to recombinant yeast mitochondriaFEBS JOURNAL, Issue 10 2000Identification of necessary physico-chemical determinants The association of rat brain hexokinase with heterologous recombinant yeast mitochondria harboring human porin (Yh) is comparable to that with rat liver mitochondria in terms of cation requirements, cooperativity in binding, and the effect of amphipathic compounds. Mg2+, which is required for hexokinase binding to all mitochondria, can be replaced by other cations. The efficiency of hexokinases, however, depends on the valence of hydrophilic cations, or the partition of hydrophobic cations in the membrane, implying that these act by reducing a prohibitive negative surface charge density on the outer membrane rather than fulfilling a specific structural requirement. Macromolecular crowding (using dextran) has dual effects. Dextran added in excess increases hexokinase binding to yeast mitochondria, according to the porin molecule they harbor. This effect, significant with wild-type yeast mitochondria, is only marginal with Yh as well as rat mitochondria. On the other hand, an increase in the number of hexokinase binding sites on mitochondria is also observed. This increase, moderate in wild-type organelles, is more pronounced with Yh. Finally, dextran, which has no effect on the modulation of hexokinase binding by cations, abolishes the inhibitory effect of amphipathic compounds. Thus, while hexokinase binding to mitochondria is predetermined by the porin molecule, the organization of the latter in the membrane plays a critical role as well, indicative that porin must associate with other mitochondrial components to form competent binding sites on the outer membrane. [source] Mutual Fund Performance: Measurement and Evidence1FINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 2 2010Keith Cuthbertson C15; G11; C14 The paper provides a critical review of empirical findings on the performance of mutual funds, mainly for the US and UK. Ex-post, there are around 0-5% of top performing UK and US equity mutual funds with truly positive-alpha performance (after fees) and around 20% of funds that have truly poor alpha performance, with about 75% of active funds which are effectively zero-alpha funds. Key drivers of relative performance are, load fees, expenses and turnover. There is little evidence of successful market timing. Evidence suggests past winner funds persist, when rebalancing is frequent (i.e., less than one year) and when using sophisticated sorting rules (e.g., Bayesian approaches) - but transactions costs (load and advisory fees) imply that economic gains to investors from winner funds may be marginal. The US evidence clearly supports the view that past loser funds remain losers. Broadly speaking results for bond mutual funds are similar to those for equity funds. Sensible advice for most investors would be to hold low cost index funds and avoid holding past ,active' loser funds. Only sophisticated investors should pursue an active ex-ante investment strategy of trying to pick winners - and then with much caution. [source] Western utopianism/dystopianism and the political mediocrity of critical urban researchGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3-4 2002Guy Baeten This paper seeks to summarise the interplay between utopian and dystopian thinking throughout the twentieth century with a particular focus on the city. The gradually shrinking appeal of the socialist utopia and its replacement with the globalised free,market as a ,revanchist utopia' left socialist utopian thinking in a state of disarray towards the end of the previous century. Utopian thinking, both as a literary and political genre has been rendered marginal in contemporary political practices. Urban dystopia, or ,Stadtschmerz', is now prevalent in critical Western thinking about city and society. It is concluded that the declining political impact of critical urban research is caused partly by its lack of engagement with crafting imaginative alternative futures for the city. The works by Sennett, Sandercock and the Situationists, among others, may contain elements to reverse the current utopian malaise in urban research. [source] Spaces of Utopia and Dystopia: Landscaping the Contemporary CityGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3-4 2002Gordon MacLeod Some of the most recent literature within urban studies gives the distinct impression that the contemporary city now constitutes an intensely uneven patchwork of utopian and dystopian spaces that are, to all intents and purposes, physically proximate but institutionally estranged. For instance, so,called edge cities (Garreau, 1991) have been heralded as a new Eden for the information age. Meanwhile tenderly manicured urban villages, gated estates and fashionably gentrified inner,city enclaves are all being furiously marketed as idyllic landscapes to ensure a variety of lifestyle fantasies. Such lifestyles are offered additional expression beyond the home, as renaissance sites in many downtowns afford city stakeholders the pleasurable freedoms one might ordinarily associate with urban civic life. None,the,less, strict assurances are given about how these privatized domiciliary and commercialized ,public' spaces are suitably excluded from the real and imagined threats of another fiercely hostile, dystopian environment ,out there'. This is captured in a number of (largely US) perspectives which warn of a ,fortified' or ,revanchist' urban landscape, characterized by mounting social and political unrest and pockmarked with marginal interstices: derelict industrial sites, concentrated hyperghettos, and peripheral shanty towns where the poor and the homeless are increasingly shunted. Our paper offers a review of some key debates in urban geography, planning and urban politics in order to examine this patchwork,quilt urbanism, In doing so, it seeks to uncover some of the key processes through which contemporary urban landscapes of utopia and dystopia come to exist in the way they do. [source] TNC Strategies and Variations in Intra-firm Trade: The Case of Foreign Manufacturing Affiliates in SwedenGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 1 2000Inge Ivarsson The aim of this paper is to contribute to the understanding of the forms and determinants of intra-firm trade, i.e. international trade between different units under common TNC ownership, this being a major indication of ,deep economic integration' between developed countries in the 1990s. Theoretically, intra-firm trade can be explained by the existence of economies of common governance and are often found to be associated with R&D-intensive industries and economies of scale. In empirical studies, intra-firm trade is often found to consist of intermediate inputs goods, resulting in vertically integrated production chains. The study is based on detailed firm-level data from around 300 foreign majority-owned affiliates (MOFAs) in manufacturing, in Sweden in 1993. The results show that intra-firm sales by MOFAs in Sweden are as high as those found in studies of manufacturing affiliates of US TNCs. Almost all of MOFAs' intra-firm exports are finished products, while intra-firm imports consist of material inputs and finished products for resale. This suggests that these MOFAs are only marginal involved in vertically integrated production chains, especially in terms of exports. The results of a regression analysis complement earlier studies by showing that the level and composition of intra-firm trade is significantly affected by the international strategy applied by TNCs when operating foreign manufacturing affiliates. Intra-firm exports of finished products and material inputs are positively associated with efficiency-seeking FDI, e.g. affiliates engaged in rationalised production. Market-seeking FDI is associated with intra-firm imports of complementary finished products for resale. By contrast, resource-seeking and strategic asset-seeking FDI was negatively associated with intra-firm trade. [source] ,It's a public, I reckon': Publicness and a Suburban Shopping Mall in Sydney's SouthwestGEOGRAPHICAL RESEARCH, Issue 2 2010ADAM TYNDALL Abstract Traditionally, public space has been perceived as an integral part of fully functioning liberal democracy. Yet much research argues that public space is in decline due to regimes of neoliberal governance paralleled with a growth in quasi-public spaces such as shopping malls, casinos and gated communities. It is argued that these new spatial forms posit a commercialised, sanitised and ultimately exclusionary urban form in place of more egalitarian, engaging and ultimately democratic public spaces. Increasingly, however, urban research has questioned the veracity of the claims made about the nature of traditional public space as well as investigating the marginal and contingent nature of publicness as constituted by and enacted in a variety of places. Drawing on Foucault's concept of heterotopic space, this paper reports on a qualitative study based on focus group interviews conducted with users of a suburban shopping mall in Sydney's southwest. The research uncovers both a more complex and less overtly deterministic publicness than has previously been identified in such spaces. From these findings the paper argues for a conception of publicity which moves beyond the zero-sum game approach endemic in much work in this area to one which analyses the qualitative effect quasi-public spaces are having on the nature of publicness in the Australian context. The paper concludes by arguing that a rethinking of publicness allows room for the emergence of a more progressive public ethic. [source] | |||||||||||||||||||||||||||||||