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Selected AbstractsPatients with a major depressive episode responding to treatment with repetitive transcranial magnetic stimulation (rTMS) are resistant to the effects of rapid tryptophan depletionDEPRESSION AND ANXIETY, Issue 8 2007John P. O'Reardon M.D. Abstract Repetitive transcranial magnetic stimulation (rTMS) appears to be efficacious in the treatment of major depression based on the results of controlled studies, but little is known about its antidepressant mechanism of action. Mood sensitivity following rapid tryptophan depletion (RTD) has been demonstrated in depressed patients responding to SSRI antidepressants and phototherapy, but not in responders to electroconvulsive therapy (ECT). We sought to study the effects of RTD in patients with major depression responding to a course of treatment with rTMS. Twelve subjects treated successfully with rTMS monotherapy underwent both RTD and sham depletion in a double-blind crossover design. Depressive symptoms were assessed using both a modified Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI). The differential change in depression scores across the procedures was compared. No significant difference in mood symptoms was noted between RTD and the sham-depletion procedure on either continuous measures of depression, or in the proportions of subjects that met predefined criteria for a significant degree of mood worsening. Responders to rTMS are resistant to the mood perturbing effects of RTD. This suggests that rTMS does not depend on the central availability of serotonin to exert antidepressant effects in major depression. Depression Anxiety 24:537,544, 2007. © 2006 Wiley-Liss, Inc. [source] Improved glycaemic control with insulin glargine plus insulin lispro: a multicentre, randomized, cross-over trial in people with Type 1 diabetesDIABETIC MEDICINE, Issue 3 2006S. G. Ashwell Abstract Aims To compare blood glucose control using insulin glargine + insulin lispro with that on NPH insulin + unmodified human insulin in adults with Type 1 diabetes managed with a multiple injection regimen. Methods In this 32-week, five-centre, two-way cross-over study, people with Type 1 diabetes (n = 56, baseline HbA1c 8.0 ± 0.8%) were randomized to evening insulin glargine + mealtime insulin lispro or to NPH insulin (once- or twice-daily) + mealtime unmodified human insulin. Each 16-week period concluded with a 24-h inpatient plasma glucose profile. Results HbA1c was lower with glargine + lispro than with NPH + human insulin [7.5 vs. 8.0%, difference ,0.5 (95% CI ,0.7, ,0.3) %, P < 0.001]. This was confirmed by an 8% lower 24-h plasma glucose area under the curve (AUC) (187 vs. 203 mmol l,1 h,1, P = 0.037), a 24% reduction in plasma glucose AUC > 7.0 mmol/l1 (47 vs. 62 mmol l,1 h,1, P = 0.017) and a 15% lower post-prandial plasma glucose AUC (75 vs. 88 mmol l,1 h,1, P = 0.002). There was no reduction in night-time plasma glucose AUC or increase in plasma glucose area < 3.5 mmol/l. Monthly rate of nocturnal hypoglycaemia was reduced by 44% with glargine + lispro (0.66 vs. 1.18 episodes/month, P < 0.001). Conclusions Compared with NPH insulin + unmodified human insulin, the combination of insulin glargine with a rapid-acting insulin analogue as multiple-injection therapy for Type 1 diabetes improves overall glycaemic control as assessed by HbA1c and 24-h plasma glucose monitoring to a clinically significant degree, together with a reduction in nocturnal hypoglycaemia. [source] Laboratory simulation of the salt weathering of schist: II.EARTH SURFACE PROCESSES AND LANDFORMS, Issue 5 2007Fragmentation of fine schist particles Abstract Recent developments in long term landform evolution modelling have created a new demand for quantitative salt weathering data, and in particular data describing the size distribution of the weathered rock fragments. To enable future development of rock breakdown models for use in landscape evolution and soil production models, laboratory work was undertaken to extend existing schist/salt weathering fragmentation studies to include an examination of the breakdown of sub-millimetre quartz chlorite schist particles in a seasonally wet tropical climate. Laser particle sizing was used to assess the impact of different experimental procedures on the resulting particle size distribution. The results reveal that salt weathering under a range of realistic simulated tropical wet season conditions produces a significant degree of schist particle breakdown. The fragmentation of the schist is characterized by splitting of the larger fragments into mid-sized product with finer material produced, possibly from the breakdown of mid-sized fragments when weathering is more advanced. Salinity, the salt addition method and temperature were all found to affect weathering rates. Subtle differences in mineralogy also produce variations in weathering patterns and rates. It is also shown that an increase in drying temperature leads to accelerated weathering rates, however, the geometry of the fracture process is not significantly affected. Copyright © 2006 John Wiley & Sons, Ltd. [source] Cerebral Cortical Gyrification: A Preliminary Investigation in Temporal Lobe EpilepsyEPILEPSIA, Issue 2 2007Lisa Ronan Summary:,Purpose: To introduce a measure of global cortical folding in epilepsy by using stereology. Subtle developmental abnormalities associated with temporal lobe epilepsy may encompass brain morphologic changes such as an aberrant degree of cortical folding. Methods: Stereologic methods of volume and surface-area estimation were applied to in vivo MR brain-image data of a cohort of 20 temporal lobe epilepsy (TLE) patients (10 men, 10 women), and 20 neurologically normal controls (10 men, 10 women). Indices of cerebral gyrification and cerebral atrophy were generated. The impact of side of seizure onset, age at onset, history of febrile seizures, presence or absence of lesions, and presence or absence of secondarily generalized seizures on cerebral gyrification was assessed. Results: Although no significant group mean difference was found in the degree of cerebral gyrification between patients and controls, five of 10 of male patients had an abnormal gyrification when compared with male controls. One female patient had a significant change in gyrification compared with female controls. In general, patients with TLE demonstrated a significant degree of global cerebral atrophy compared with controls. Clinical factors were not demonstrated to affect significantly any of the quantitative parameters. Conclusions: The results of this study suggest that an aberrant degree of global cerebral gyrification may occur in certain clinical groups of TLE patients. These findings have implications for general theories of developmental susceptibility in TLE. [source] The Chorus Song of Cooperatively Breeding Laughing Kookaburras (Coraciiformes, Halcyonidae: Dacelo novaeguineae): Characterization and Comparison Among GroupsETHOLOGY, Issue 1 2004Myron C. Baker I studied vocalizations of laughing kookaburras in Western Australia by sampling the laugh-song choruses of eight different groups and the isolated vocalizations of four individuals of this cooperatively breeding species. These data provided a description of the acoustic structure of vocal elements of the laugh song and a between-group comparison of laugh choruses. I identified six different categories of syllables: some syllable types appear graded with modal forms predominating. Group choruses were produced by several birds vocalizing simultaneously, usually following initiation by a single bird producing one of two typical introductory sets of syllable repetitions. Statistical analyses of samples of mid-chorus vocalizations of kookaburra groups revealed that the samples from each of the eight groups clustered in principal coordinate space and the group clusters segregated from each other to a significant degree. Linear discriminant analysis assigned 24 of the 25 samples to their correct groups. These results suggest that there is group-specific vocal signature information in the laugh chorus. The within-group similarity and between-group differences may result from heritable variation or from imitation learning. Observations of the contexts of the laugh chorus vocalization supported the interpretations of others that the chorus song is involved in group advertisement of territory occupancy and in defense of the communal borders. [source] Airway inflammation: chemokine-induced neutrophilia and the class,I phosphoinositide 3-kinasesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 4 2005Matthew Abstract Class,I phosphoinositide 3-kinases (PI3K) are known to play a significant role in neutrophil chemotaxis. However, the relative contributions of different PI3K isoforms, and how these impact on lung inflammation, have not been addressed. In vitro studies using wild-type and PI3K, knockout neutrophils demonstrated the major role of the ,,isoform in chemotactic but not chemokinetic events. This was confirmed by a model of direct chemokine instillation into the airways in vivo. Within all studies, a low yet significant degree of neutrophil movement in the absence of PI3K, could be observed. No role for the ,,isoform was demonstrated both in vitro and in vivo using PI3K, kinase-dead knock-in mice. Moreover, further studies using the broad-spectrum PI3K inhibitors wortmannin or LY294002 showed no other class,I PI3K isoforms to be involved in these chemotactic processes. Here, we identify a contributory PI3K-independent mechanism of neutrophil movement, yet demonstrate PI3K, as the pivotal mediator through which the majority of neutrophils migrate into the lung in response to chemokines. These data resolve the complexities of chemokine-induced neutrophilia and PI3K signaling and define the ,,isoform as a promising target for new therapeutics to treat airway inflammatory diseases. [source] Arborol-Functionalised Tetrathiafulvalene Derivatives: Synthesis and Thin-Film FormationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2003Thierry Le Gall Abstract The syntheses of a series of novel tetrathiafulvalene derivatives substituted with four side-chains terminating in hydrophilic amidoalcohol (arborol) groups are reported, for example the tetrathiafulvalene derivative 15. Some of these arborol derivatives formed thin films by spin-coating from methanol solution onto solid supports such as glass, ITO-coated glass and gold. The quality of the films improved markedly with an increasing number of alcohol substituents at the periphery of the molecule. Optical absorption spectroscopy showed that oxidative doping of these films could be achieved chemically and electrochemically. The observation of low-energy bands in the UV/Vis absorption spectra (,max = 820 nm tailing to ca. 1300 nm) and the moderate levels of conductivity (,rt , 10,4 S cm,1) in these doped films strongly suggest that a significant degree of supramolecular order is present, with ,-, stacking of the TTF cores. To the best of our knowledge this is the first time that semiconducting behaviour has been achieved in molecular arborol systems that possess an electroactive core unit. This work offers the prospect of using spin-coated films of TTF-arborols as semiconducting charge-transport layers in optoelectronic devices. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Low-cycle fatigue of 1Cr,18Ni,9Ti stainless steel and related weld metal under axial, torsional and 90° out-of-phase loadingFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 6 2004X. CHEN ABSTRACT The fatigue behaviour of base metal and weld joints of 1Cr,18Ni,9Ti stainless steel has been studied under uniaxial, torsional and 90° out-of-phase loading. A significant degree of additional hardening is found for both base metal and weld metal under 90° out-of-phase loading. Both base metal and weld metal have the same cyclic stable stress,strain relationship under torsional cyclic loading and 90° out-of-phase cyclic loading. Base metal exhibits higher cyclic stress than weld metal under uniaxial loading, and Young's modulus and yield stress of weld metal are smaller than those of base metal. Weld metal exhibited lower fatigue resistance than base metal under uniaxial and torsional loading, but no significant difference was found between the two materials under 90° out-of-phase loading. A large scatter of fatigue life is observed for weld metal, perhaps because of heterogeneity of the microstructure. The Wang,Brown (WB) damage parameter and the Fatemi,Socie (FS) damage parameter, both based on the shear critical plane approach, were evaluated relative to the fatigue data obtained. [source] Caveolin-1 influences P2X7 receptor expression and localization in mouse lung alveolar epithelial cellsFEBS JOURNAL, Issue 12 2007K. Barth The P2X7 receptor has recently been described as a marker for lung alveolar epithelial type I cells. Here, we demonstrate both the expression of P2X7 protein and its partition into lipid rafts in the mouse lung alveolar epithelial cell line E10. A significant degree of colocalization was observed between P2X7 and the raft marker protein Caveolin-1; also, P2X7 protein was associated with caveolae. A marked reduction in P2X7 immunoreactivity was observed in lung sections prepared from Caveolin-1-knockout mice, indicating that Caveolin-1 expression was required for full expression of P2X7 protein. Indeed, suppression of Caveolin-1 protein expression in E10 cells using short hairpin RNAs resulted in a large reduction in P2X7 protein expression. Our data demonstrate a potential interaction between P2X7 protein and Caveolin-1 in lipid rafts, and provide a basis for further functional and biochemical studies to probe the physiologic significance of this interaction. [source] The Life and Death of Public Organizations: A Question of Institutional Design?GOVERNANCE, Issue 3 2010ARJEN BOIN Why do some public organizations grow old and others die young? Since Herbert Kaufman first posed this question, considerable research has been devoted to answering it. The findings of that research suggest that the design of new public organizations affects, to a significant degree, their survival chances. In this article, we test whether and how "design factors" affected the durability of the so-called New Deal organizations initiated under FDR's first term. Our findings confirm that design factors do matter, but their effects change over time. We draw out some potential implications for institutional design and sketch a renewed research agenda to determine why some public organizations survive environmental pressure whereas others succumb to it. [source] Identifying the Role of Moral Hazard in International Financial MarketsINTERNATIONAL FINANCE, Issue 1 2004Steven B. Kamin Abstract Considerable attention has been paid to the possibility that large-scale IMF-led financing packages may have distorted incentives in international financial markets, leading private investors to provide more credit to emerging market countries, and at lower interest rates, than might otherwise have been the case. Yet, prior attempts to identify such distortions have yielded mixed evidence, at best. This paper makes three contributions to our ability to assess the empirical importance of moral hazard in international financial markets. First, it is argued that, because large international ,bail-outs' did not commence until the 1995 Mexican crisis, financial indicators prior to that time could not have reflected a significant degree of this type of moral hazard. Therefore, one test for the existence of moral hazard is that the access of emerging markets to international credit is significantly easier than it was prior to 1995. Second, the paper argues that because private investors expect large-scale IMF-led packages to be extended primarily to economically or geo-politically important countries, moral hazard, if it exists, should lead these countries to have easier terms of access to credit than smaller, non-systemically important countries. Finally, in addition to looking at bond spreads, the focus of earlier empirical analyses of moral hazard, the paper also examines trends in capital flows to gauge the access of emerging market countries to external finance. Looking at the evidence in light of these considerations, the paper concludes that there is little support for the view that moral hazard is significantly distorting international capital markets at the present time. [source] Impact of COPD severity on physical disability and daily living activities: EDIP-EPOC I and EDIP-EPOC II studiesINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 5 2009J. M. Rodriguez Gonzalez-Moro Summary Aims:, The severity of chronic obstructive pulmonary disease (COPD) is associated to patients' health-related quality of life (HRQL). Physical impairment increasingly affects daily activities creating economic, social and personal burden for patients and their families. This burden should be considered in the management of COPD patients; therefore, we intended to assess the impact of the disease severity on physical disability and daily activities. Methods:, Two epidemiological observational cross-sectional descriptive studies were carried out in 1596 patients with moderate COPD and 2012 patients with severe or very severe COPD in the routine clinical practice. Demographic and basic clinical-epidemiological data were collected and patients completed questionnaires to assess their physical disability because of COPD [Medical Research Council (MRC)], COPD repercussion on daily activities [London Chest Activity of Daily Living (LCADL)], job, economy and family habits and their health status [EQ-5D visual analogue scale (VAS)]. Results:, In all, 37% of severe/very severe COPD patients and 10% of moderate (p < 0.0001) had MRC grades 4 and 5. Mean global LCADL was significantly higher in severe/very severe than in moderate patients [29.6 (CI 95%: 28.91,30.25) vs. 21.4 (CI 95%: 20.8,21.9); p < 0.0001]. COPD job impact and economic and family habits repercussions were significantly higher and health status significantly worse in severe/very severe cases than in patients with moderate COPD. Conclusions:, COPD severity is highly associated with physical disability by MRC grading, with functionality on daily activities and with impairment of other social and clinical activities. Moderate COPD patients show already a significant degree of impairment in all these parameters. [source] Neuropathological correlates to clinically defined dementia with Lewy bodiesINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2001E. Londos Abstract Objectives To analyse the neuropathological changes behind clinically defined dementia with Lewy bodies (clinDLB) compared with clinically diagnosed Alzheimer's disease (clinAD). Methods The prevalence of neuropathological findings in 48 clinDLB and 45 clinAD cases was compared. Sixteen clinDLB and 10 clinAD cases were reassessed with ,-synuclein staining for Lewy bodies (LB). Results Alzheimer pathology was found in 81% of the clinDLB and 93% of the clinAD cases. The clinDLB group had a higher prevalence of frontal white matter pathology, mostly of ischemic type, and a more severe degeneration of the substantia nigra compared with the clinAD group. In hematoxylin,eosin staining, LBs were identified in seven (15%) of the clinDLB and in four (9%) of the clinAD group. In ,-synuclein staining, 38% of the clinDLB and 40% of the clinAD cases exhibited LBs. The cases without LBs, in the clinDLB group, had AD pathology in combination with frontal white matter disease. Vascular pathology of significant degree was prevalent in more than 40% of all the cases with verified LBs regardless of clinical diagnosis. Conclusion Consecutive dementia cases, fulfilling the clinical consensus criteria for DLB, may exhibit combinations of neuropathological changes which in themselves can explain the clinical picture of DLB even when LBs are absent. Copyright © 2001 John Wiley & Sons, Ltd. [source] Human resource development in the Sultanate of OmanINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2002Pawan S. Budhwar This study explores the scenario of human resource development (HRD) in the Sultanate of Oman. The investigation was conducted with the help of a questionnaire survey in stateowned enterprises (SOEs). The research findings highlight an increased emphasis on HRD initiatives at a national level in Omani firms. There is a significant degree of awareness among the top managers regarding the benefits of a strategic approach to HRD. Despite all this, the implementation of HRD programmes has not been particularly successful. This is because the state has not been able to develop the skills and competencies of the Omani workforce to the levels required under the sixth national five,year plan. The article makes a number of recommendations in this regard. It also highlights key research areas for further examination. [source] Socio-economic distance and spatial patterns in unemploymentJOURNAL OF APPLIED ECONOMETRICS, Issue 4 2002Timothy G. Conley This paper examines the spatial patterns of unemployment in Chicago between 1980 and 1990. We study unemployment clustering with respect to different social and economic distance metrics that reflect the structure of agents' social networks. Specifically, we use physical distance, travel time, and differences in ethnic and occupational distribution between locations. Our goal is to determine whether our estimates of spatial dependence are consistent with models in which agents' employment status is affected by information exchanged locally within their social networks. We present non-parametric estimates of correlation across Census tracts as a function of each distance metric as well as pairs of metrics, both for unemployment rate itself and after conditioning on a set of tract characteristics. Our results indicate that there is a strong positive and statistically significant degree of spatial dependence in the distribution of raw unemployment rates, for all our metrics. However, once we condition on a set of covariates, most of the spatial autocorrelation is eliminated, with the exception of physical and occupational distance. Racial and ethnic composition variables are the single most important factor in explaining the observed correlation patterns. Copyright © 2002 John Wiley & Sons, Ltd. [source] Parental Behavior and the Quality of Adolescent Friendships: A Social-Contextual PerspectiveJOURNAL OF MARRIAGE AND FAMILY, Issue 3 2002Ming Cui On the basis of an evolving social-contextual perspective, the authors predicted and found that socioeconomic advantage in terms of income and parental education promotes supportive and inhibits hostile parental behaviors toward an adolescent child (N= 221). These parental behaviors predicted similar actions by the child toward a close friend 4 years later. In turn adolescent supportiveness promoted close friendship ties, whereas hostility diminished the quality of friendships. The results support the notion that, to a significant degree, the quality of family interactions: (a) arises from the social context surrounding the family, (b) is transmitted across generations, and (c) has a demonstrable impact on the quality of adolescents' social ties outside the family. [source] Retrograde melt,residue interaction and the formation of near-anhydrous leucosomes in migmatitesJOURNAL OF METAMORPHIC GEOLOGY, Issue 6 2010R. W. WHITE Abstract Considering physical segregation of melt from its residue, the chemical potentials of the components (oxides) are the same in both when segregation occurs. Then, as P,T conditions change, gradients in chemical potential are established between the melt-rich domains and residue permitting diffusional interaction to occur. In particular, on cooling, the chemical potential of H2O becomes higher in the melt segregation than in the residue, particularly when biotite becomes stable in the residue assemblage. Diffusion of water from the melt to the residue promotes crystallization of anhydrous products from the melt and hydrous products in the residue. This diffusive process, when coupled with melt loss from the rocks subsequent to some degree of crystallization, can result in a significant degree of anhydrous leucosome being preserved in a migmatite with only minor retrogression of the residue. If H2O can diffuse between the melt segregation and all of the residue, then no apparent selvedge between the two will be observed. Alternatively, if H2O can diffuse between the melt segregation and only part of the residue, then a distinct selvedge may be produced. Diffusion of H2O into the residue may be in part responsible for the commonly anhydrous nature of leucosomes, especially in granulite facies migmatites. Diffusion of other relatively mobile species such as Na2O and K2O has a lesser effect on overall melt crystallization but can change the proportion of quartz, plagioclase and K-feldspar in the resultant leucosome. The diffusion of H2O out of the melt results in the enhanced crystallization of the melt in the segregation and increases the amount of resulting anhydrous leucosome relative to the amount produced if melt crystallized in chemical isolation from the residue. For high residue:melt ratios, the proportion of resulting near-anhydrous leucosome can approach that of the proportion of melt present at the onset of cooling with only minor loss of melt from a given segregation required. Crystallization of melt segregations via the diffusion of H2O out of them into the host may also play a major role in driving melt-rich segregations across key rheological transitions that would allow the expulsion of remaining melt from the system. [source] Novel role for aspartoacylase in regulation of BDNF and timing of postnatal oligodendrogenesisJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2006Jeremy S. Francis Abstract Neuronal growth factors are thought to exert a significant degree of control over postnatal oligodendrogenesis, but mechanisms by which these factors coordinateoligodendrocyte development with the maturation of neural networks are poorly characterized. We present here a developmental analysis of aspartoacylase (Aspa)-null tremor rats and show a potential role for this hydrolytic enzyme in the regulation of a postnatal neurotrophic stimulus that impacts on early stages of oligodendrocyte differentiation. Abnormally high levels of brain-derived neurotrophic factor (BDNF) expression in the Aspa -null Tremor brain are associated with dysregulated oligodendrogenesis at a stage in development normally characterized by high levels of Aspa expression. BDNF promotes the survival of proliferating cells during the early stages of oligodendrocyte maturation in vitro, but seems to compromise the ability of these cells to populate the cortex in vivo. Aspartoacylase activity in oligodendrocytes is shown to provide for the negative regulation of BDNF in neurons, thereby determining the availability of a developmental stimulus via a mechanism that links oligodendroglial differentiation with neuronal maturation. © 2006 Wiley-Liss, Inc. [source] The importance of local-scale openness within regions dominated by closed woodland,JOURNAL OF QUATERNARY SCIENCE, Issue 6 2007Ralph Fyfe Abstract New and existing pollen data from Wales, UK, are used to assess the level of landscape openness at the regional and local scale. At the regional scale, the existing pollen data support the high-forest model of vegetation structure by 6000 cal. yr. BC prior to any palynological signal for anthropogenic impact in the region. New data from two sites in southwest Wales follow the general regional pattern of early to middle Holocene vegetation succession, but are striking owing to maintenance of high non-arboreal pollen percentages (NAPs) throughout the mid-Holocene. It is argued that these NAPs indicate that a significant degree of openness can be found at the local level (and beyond the confines of the peat-forming site) within regions characterised by closed woodland. It is possible that woodland development in these areas may have been suppressed by reduced drainage, although the role of grazing animals in maintenance of clearings cannot be assessed. Implications for this local degree of openness are discussed, in particular the significance of vegetation heterogeneity at the local scale for the construction of place or locale for prehistoric communities. Copyright © 2006 John Wiley & Sons, Ltd. [source] THE SPIRIT OF DEMOCRACY AND THE RHETORIC OF EXCESSJOURNAL OF RELIGIOUS ETHICS, Issue 1 2007Jeffrey Stout ABSTRACT If militarism violates the ideals of liberty and justice in one way, and rapidly increasing social stratification violates them in another, then American democracy is in crisis. A culture of democratic accountability will survive only if citizens revive the concerns that animated the great reform movements of the past, from abolitionism to civil rights. It is crucial, when reasoning about practical matters, not only to admit how grave one's situation is, but also to resist despair. Therefore, the fate of democracy depends, to some significant degree, on how we choose to describe the crisis. Saying that we have already entered the new dark ages or a post-democratic era may prove to be a self-fulfilling prophecy, because anyone who accepts this message is apt to give up on the hard work of organizing and contestation that is needed to hold political representatives accountable to the people. This paper asks how one might strike the right balance between accuracy and hope in describing the democracy's current troubles. After saying what I mean by democracy and what I think the current threats to it are, I respond to Romand Coles's criticisms of reservations I have expressed before about rhetorical excess in the works of Stanley Hauerwas, Alasdair MacIntyre, and Richard Rorty. This leads to a discussion of several points raised against me by Hauerwas. A digression offers some of my reasons for doubting that John Howard Yoder's biblical scholarship vindicates Hauerwas's version of pacifism. The paper concludes by arguing that Sheldon Wolin's work on the evisceration of democracy, though admirably accurate in its treatment of the dangers posed by empire and capital, abandons the project of democratic accountability too quickly in favor of the romance of the fugitive. [source] Pulsed Electric Current Sintering of Silicon NitrideJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2003Motohiro Suganuma Pulsed electric current sintering (PECS) has been used to densify ,-Si3N4 powder doped with oxide additives of Y2O3 and Al2O3. A full density (>99%) was achieved with virtually no transformation to ,-phase, resulting in a microstructure with fine equiaxed grains. With further holding at the sintering temperature, the ,-to-, phase transformation took place, concurrent with an exaggerated grain growth of a limited number of elongated ,-grains in a fine-grained matrix, leading to a distinct bimodal grain size distribution. The average grain size was found to obey a cubic growth law, indicating that the growth is diffusion-controlled. In contrast, the densification by hot pressing was accompanied by a significant degree of the phase transformation, and the subsequent grain growth gave a broad normal size distribution. The apparent activation energy for the phase transformation was as high as 1000 kJ/mol for PECS, almost twice the value for hot pressing (,500 kJ/mol), thereby causing the retention of ,-phase during the densification by PECS. [source] Sibling death clustering in India: state dependence versus unobserved heterogeneityJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 4 2006Wiji Arulampalam Summary., Data from a range of environments indicate that the incidence of death is not randomly distributed across families but, rather, that there is a clustering of death among siblings. A natural explanation of this would be that there are (observed or unobserved) differences across families, e.g. in genetic frailty, education or living standards. Another hypothesis that is of considerable interest for both theory and policy is that there is a causal process whereby the death of a child influences the risk of death of the succeeding child in the family. Drawing language from the literature on the economics of unemployment, the causal effect is referred to here as state dependence (or scarring). The paper investigates the extent of state dependence in India, distinguishing this from family level risk factors that are common to siblings. It offers some methodological innovations on previous research. Estimates are obtained for each of three Indian states, which exhibit dramatic differences in socio-economic and demographic variables. The results suggest a significant degree of state dependence in each of the three regions. Eliminating scarring, it is estimated, would reduce the incidence of infant mortality (among children who are born after the first child) by 9.8% in the state of Uttar Pradesh, 6.0% in West Bengal and 5.9% in Kerala. [source] The molecular basis of factor V and VIII procofactor activationJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 12 2009R. M. CAMIRE Summary., Activation of precursor proteins by specific and limited proteolysis is a hallmark of the hemostatic process. The homologous coagulation factors (F)V and FVIII circulate in an inactive, quiescent state in blood. In this so-called procofactor state, these proteins have little, if any procoagulant activity and do not participate to any significant degree in their respective macromolecular enzymatic complexes. Thrombin is considered a key physiological activator, cleaving select peptide bonds in FV and FVIII which ultimately leads to appropriate structural changes that impart cofactor function. As the active cofactors (FVa and FVIIIa) have an enormous impact on thrombin and FXa generation, maintaining FV and FVIII as inactive procofactors undoubtedly plays an important regulatory role that has likely evolved to maintain normal hemostasis. Over the past three decades there has been widespread interest in studying the proteolytic events that lead to the activation of these proteins. While a great deal has been learned, mechanistic explanations as to how bond cleavage facilitates conversion to the active cofactor species remain incompletely understood. However, recent advances have been made detailing how thrombin recognizes FV and FVIII and also how the FV B-domain plays a dominant role in maintaining the procofactor state. Here we review our current understanding of the molecular process of procofactor activation with a particular emphasis on FV. [source] Social structure of a polygynous tent-making bat, Cynopterus sphinx (Megachiroptera)JOURNAL OF ZOOLOGY, Issue 2 2000Jay F. Storz Abstract The social structure of an Old World tent-making bat Cynopterus sphinx (Megachiroptera), was investigated in western India. A combination of census and mark,recapture data over 2 years (1996,98) was used to infer the form of the mating system, compositional stability of social groups and mode of new social group formation. The breeding population of C. sphinx was subdivided into diurnal roosting colonies, each of which contained one to five discrete roosting groups and often one or more solitary bats in adjacent roosts. Bats most frequently roosted in stem tents constructed in the flower/fruit clusters of the kitul palm Caryota urens. Temporal variation in social structure was assessed using visual census data for a subset of the study population over 3 years (1995,98) spanning six consecutive reproductive periods. The sex and age composition of diurnal roosting groups indicated a polygynous harem-forming mode of social organization, as groups invariably contained a single adult male, 1,37 reproductive females and their dependent young (n= 33 harems). Harem size averaged 6.1 adults in the wet season (n= 19, sd= 3.5) and 13.6 adults in the dry season (n= 14, sd= 8.5). The same harem social configuration was maintained year-round, despite a high degree of synchrony and seasonality in the timing of reproduction. Juveniles of both sexes dispersed after weaning and sexually immature bats were never present in harems at the time of parturition. Adult females often remained associated as roostmates from one parturition period to the next, and group cohesion was unaffected by turnover of harem males. Adult females frequently transferred among roosts within the same colony, and harems underwent periodic fissions and fusions. The founding of new harems most often resulted from the fissioning of previously cohesive harems within the same colony. However, some harems contained disproportionate numbers of yearling females, indicating that new groups are also founded by nulliparous females of the same age cohort. A significant degree of heterogeneity in age composition among harems was revealed in the 1998 dry season, but was unrelated to age-stratification of tent roosts. Although formation of new harems may be non-random with respect to age composition of the founders, founding events are not restricted to newly created tents and often involve recolonization of previously occupied roosts. [source] Study of the Segmental Dynamics in Semi-Crystalline Poly(lactic acid) using Mechanical SpectroscopiesMACROMOLECULAR BIOSCIENCE, Issue 4 2005Joăo F. Mano Abstract Summary: The glass transition of poly(L -lactic acid) (PLLA) occurs not far above typical service temperatures (room or body temperatures) which has consequences on the material properties during its use, such as damping or the occurrence of structural relaxation. This work aims at characterising the glass transition dynamics of a semi-crystalline PLLA using both dynamic mechanical analysis (DMA) and thermally stimulated recovery (TSR). The main viscoelastic parameters have been characterised at 1 Hz using DMA and the master curve obtained after isothermal experiments at different temperatures provided a full picture of the solid-state rheological behaviour throughout a wide frequency range. The activation energies calculated from the shift factors agree with the TSR ones, exhibiting a maximum near the Tg. Above the Tg, the results can be described with the WLF model. In the glassy state, the activation energy decreases with decreasing temperatures being always higher than the prediction of the Adam and Gibbs theory, at least down to temperatures 30,°C below the Tg. This suggests the existence of non-arrested degrees of freedom in the glassy state, being consistent with the existence of a significant degree of cooperativity in the TSR results. Temperature dependence of the apparent activation energy across the glass transition. [source] Synthesis, Characterization and Ionic Conductive Properties of Phosphorylated Chitosan MembranesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 5-6 2003Ying Wan Abstract Phosphorylated chitosan membranes were prepared from the reaction of orthophosphoric acid and urea on the surface of chitosan membranes in N,N -dimethylformamide. Their ionic conductivity in the wet state was investigated. Chemical modifications contributed to improved ionic conductivities of the chitosan membranes. Compared to the unmodified chitosan membranes, it was found that hydrated phosphorylated chitosan membranes with an appropriate phosphorus content showed an increasing ionic conductivity of about one order of magnitude. The phosphorylation reaction mechanism was explained based on 13C and 31P NMR measurements. It was also observed that the crystallinity of the phosphorylated chitosan membranes and the corresponding swelling indices were changed pronouncedly, but these membranes did not lose either their tensile strength or thermal stability to a significant degree in comparison with the unmodified chitosan membranes. Possible reaction mechanism for preparation of phosphorylated chitosan membranes. [source] Prion protein gene polymorphisms in Saccharomyces cerevisiaeMOLECULAR MICROBIOLOGY, Issue 4 2003Catarina G. Resende Summary The yeast Saccharomyces cerevisiae genome encodes several proteins that, in laboratory strains, can take up a stable, transmissible prion form. In each case, this requires the Asn/Gln-rich prion-forming domain (PrD) of the protein to be intact. In order to further understand the evolutionary significance of this unusual property, we have examined four different prion genes and their corresponding PrDs, from a number of naturally occurring strains of S. cerevisiae. In 4 of the 16 strains studied we identified a new allele of the SUP35 gene (SUP35,19) that contains a 19-amino-acid deletion within the N-terminal PrD, a deletion that eliminates the prion property of Sup35p. In these strains a second prion gene, RNQ1, was found to be highly polymorphic, with eight different RNQ1 alleles detected in the six diploid strains studied. In contrast, for one other prion gene (URE2) and the sequence of the NEW1 gene encoding a PrD, no significant degree of DNA polymorphism was detected. Analysis of the naturally occurring alleles of RNQ1 and SUP35 indicated that the various polymorphisms identified were associated with DNA tandem repeats (6, 12, 33, 42 or 57 bp) within the coding sequences. The expansion and contraction of DNA repeats within the RNQ1 gene may provide an evolutionary mechanism that can ensure rapid change between the [PRION+] and [prion,] states. [source] Constraints on Type Ia supernova progenitor time delays from high- z supernovae and the star formation historyMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006F. Förster ABSTRACT We re-assess the question of a systematic time delay between the formation of the progenitor and its explosion in a Type Ia supernova (SN Ia) using the Hubble Higher- z Supernova Search sample. While a previous analysis indicated a significant time delay, with a most likely value of 3.4 Gyr, effectively ruling out all previously proposed progenitor models, our analysis shows that the time-delay estimate is dominated by systematic errors, in particular due to uncertainties in the star formation history (SFH). We find that none of the popular progenitor models under consideration can be ruled out with any significant degree of confidence. The inferred time delay is mainly determined by the peak in the assumed SFH. We show that, even with a much larger supernova sample, the time-delay distribution cannot be reliably reconstructed without better constraints on the SFH. [source] Coupling between limb tremor and postural sway in Parkinson's diseaseMOVEMENT DISORDERS, Issue 3 2008Graham Kerr BSc, MPhED Abstract Increased tremor and postural instability are motor problems commonly associated with Parkinson's disease (PD). Despite the similarity between these oscillatory forms, little is known about the relation between them, especially for individuals with enhanced tremor. This study was designed to examine the nature of any relation between center of pressure (COP) excursions and postural/resting limb tremor of young, older individuals, and Parkinsonian participants in their different medication states. The resting and postural tremor for the PD participants was characterized by a single, prominent peak frequency between 4 and 7 Hz. The postural tremor for young/older participants contained smaller peaks between 1 to 4 and 7 to 12 Hz although no prominent peak was seen in their resting tremor. The AP and ML COP dynamics of all participants was characterized by a major peak between 0.1 and 0.5 Hz. An additional peak was observed in the COP output of the PD participants between 4 and 7 Hz. While no tremor-COP coupling was observed for the young/old groups, coherence analysis revealed a significant degree of coupling between COP motion and tremor between 4 and 7 Hz for PD participants. These results highlight that the amplified tremor in PD can manifest itself in COP dynamics. This finding may have implications for postural stability for this patient group. © 2007 Movement Disorder Society [source] Order and Disorder in Powder Mixtures: Spatial Distribution Functions as Tools to Assess Powder HomogeneityPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 5-6 2008Albert Mihranyan Abstract In interactive mixtures with small carrier particles, the content variability is often higher than predicted by available models despite the significant degree of interaction visualized with Scanning Electron Microscopy (SEM). The present work details how pair-correlation functions can be used to reveal information about the spatial distribution of mixture constituents and their interactions. SEM pictures of a 2,% w/w oxazepam/sodium starch glycolate (SSG) mixture were recorded (n = 14). The constituent coordinates were extracted and pair-correlation functions as well as the cross-correlation function were calculated. A significant degree of interaction was observed between the constituents in the experimental mixture, compared to a randomized control system. In particular, the probability of finding an oxazepam particle was especially high inside the perimeter of the carrier particle and along its edges. The observed cross-correlation between oxazepam and SSG particles was periodic and repeated at distances corresponding to 1,1.5 carrier diameters. It was concluded that interactive mixtures of powders can be compared to disordered/amorphous solids since both exhibit short-range order, whilst lacking long-range translational periodicity. [source] | |||||||||||||||||||||||||||||||||||||||||||