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Grey
Kinds of Grey Terms modified by Grey Selected AbstractsEpidemiology of unarmed threats in the emergency departmentEMERGENCY MEDICINE AUSTRALASIA, Issue 4 2005Jonathan C Knott Abstract Objective:, To evaluate the precipitants, subject characteristics, nature and outcomes of unarmed threats in the ED. Methods:, A 12 month prospective survey of security codes precipitated by an unarmed threat (Code Grey). Results:, Data were collected on 151 subjects. The Code Grey rate was 3.2/1000 ED presentations. They were most frequent on Saturday and in the late evening/early morning. There were verbal or physical threats of violence made to staff on 104 occasions (69%, 95% confidence interval [CI] 61,76) and a perceived threat of patient self-harm on 114 occasions (76%, 95% CI 68,82). Median time to be seen by a doctor was 8 min (interquartile range [IQR]: 2,21 min) and median time from presentation to Code was 59 min (IQR: 5,222 min). Sixteen subjects (11%, 95% CI 6,17) had a history of violence, 45 (30%, 95% CI 23,38) were affected by alcohol, 25 (17%, 95% CI 11,24) had used illicit drugs and 79 (52%, 95% CI 44,60) had a significant mental illness contributing to the Code Grey. Seventy-one patients (47%, 95% CI 39,55) required psychiatric admission, 49 (79%, 95% CI 66,88) involuntarily. Conclusion:, Acutely agitated subjects pose a threat to themselves and the staff caring for them. The reason for the agitation is multifactorial and the majority arrive in a behaviourally disturbed state requiring early intervention. The times most likely to result in a Code Grey coincide with least available resources: ED and hospital risk management policies must account for this. A coherent approach by ED to this population is required to optimize patient and staff outcomes. [source] Decolorization of simulated textile dye baths by crude laccases from Trametes hirsuta and Cerrena unicolorENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 3 2010Ulla Moilanen Abstract In this study crude laccases from the white-rot fungi Cerrena unicolor and Trametes hirsuta were tested for their ability to decolorize simulated textile dye baths. The dyes used were Remazol Brilliant Blue R (RBBR) (100,mg/L), Congo Red (12.5,mg/L), Lanaset Grey (75,mg/L) and Poly R-478 (50,mg/L). The effect of redox mediators on dye decolorization by laccases was also assessed. C. unicolor laccase was able to decolorize all the dyes tested. It was especially effective towards Congo Red and RBBR with 91 and 80% of color removal in 19.5,h despite the fact that simulated textile dye baths were used. Also Poly R-478 and Lanaset Grey were partially decolorized (69 and 48%, respectively). C. unicolor laccase did not need any mediators for removing the dyes. However, T. hirsuta laccase was only able to decolorize simulated Congo Red and RBBR dye baths (91 and 45%, respectively) in 19.5,h without mediators. When using mediators the decolorization capability was enhanced substantially, e.g. Poly R-478 was decolorized by 78% in 25.5,h. On the whole, both laccases showed potential to be used in industrial applications. [source] The Politics of Revision in Samuel Daniel's The Civil WarsENGLISH LITERARY RENAISSANCE, Issue 3 2008Gillian Wright Samuel Daniel's historical poem The Civil Wars has traditionally been regarded as a conservative text, committed in presentation and in practice to upholding the principle of hereditary right in monarchy. Such a view overlooks Daniel's many complex revisions to the poem between its first appearance in print in 1595 and the final,though still unfinished,version published in 1609. Comparative analysis of the different printed editions of the poem shows that between 1595 and 1609 Daniel's political priorities changed significantly, especially on the question of the role and legitimacy of kingship. Whereas the 1595 Civil Wars does indeed adopt a broadly conservative attitude to the rights of hereditary monarchs, the 1609 text of the poem no longer automatically endorses kingly authority but instead consistently privileges the monarch's commitment to the "publique good" and the just execution of the laws. This subtle but radical pattern of change culminates in Daniel's vignette of Elizabeth Grey and Edward IV (1609, Book VIII), which departs from the poet's sources in representing Grey's resistance to Edward's attempted seduction in explicitly politicized terms. This observable shift in Daniel's political values also foreshadows later aspects of his historiography in the prose Collection of the Historie of England (1618). (G.W.) [source] Noxious Somatic Inputs to Hypothalamic-Midbrain Projection Neurones: a Comparison of the Columnar Organisation of Somatic and Visceral Inputs to the Periaqueductal Grey in the RatEXPERIMENTAL PHYSIOLOGY, Issue 2 2002D. M. Parry The induction of Fos protein was used to localise hypothalamic neurones activated by noxious somatic stimulation. This was combined with retrograde transport of fluorescent latex microspheres from identified ,pressor' and ,depressor' sites in the dorsolateral/lateral or ventrolateral columns of the periaqueductal grey (PAG). Fos-positive neurones were found throughout the rostral hypothalamus. Of those neurones activated by noxious somatic stimuli that projected to the PAG all but one was retrogradely labelled from sites that included the lateral column. Only one neurone was double labelled following injection of tracer at a depressor site in the ventrolateral PAG. This is in marked contrast to visceroresponsive hypothalamic neurones, a larger proportion of which project to the PAG and which, as reported previously, preferentially target depressor sites in the ventrolateral sector. These results are discussed in relation to the roles of the anterior hypothalamus and the different functional columns of the PAG in co-ordinating autonomic and sensory functions in response to nociceptive inputs originating in different peripheral domains. [source] C-Nociceptor Activation of Hypothalamic Neurones and the Columnar Organisation of Their Projections to the Periaqueductal Grey in the RatEXPERIMENTAL PHYSIOLOGY, Issue 2 2002B. M. Lumb The induction of Fos protein was used to localise hypothalamic neurones activated by ramps of noxious skin heating delivered at a rate of 2.5 °C s,1 to preferentially activate C-nociceptors. This was combined with retrograde transport of cholera toxin subunit B from identified ,pressor' and ,depressor' sites in the dorsolateral/lateral or the ventrolateral columns of the periaqueductal grey. Fos-positive neurones were found throughout the rostral hypothalamus. Despite this wide distribution, those neurones double labelled retrogradely from the periaqueductal grey were focused in the lateral area of the anterior hypothalamus. More than 20% of Fos-positive neurones in this region projected to depressor sites in the ventrolateral periaqueductal grey, and 10% projected to its dorsolateral/lateral sector. These results are discussed in relation to the peripheral inputs to hypothalamic-midbrain pathways and their role in the cardiovascular responses to different components of the pain signal. [source] De Liliifloris Notulae 8.FEDDES REPERTORIUM, Issue 3-4 2010Two new Massonia species (Hyacinthaceae) from South Africa Abstract A re-investigation of the Stockholm paratype of Massonia tenellaSoland. ex Baker 1871, Drčge 3509 (K, S!) from Witbergen (,3027CA, Lady Grey) in the Eastern Cape in combination with the study of a living seedling leaf from a second locality confirmed our cautious earlier suggestion (U. & D. Müller-Doblies 1997) that it is a new species. Massonia wittebergensis U.Müll.-Doblies & D.Müll.-Doblies has a unique leaf indument in Massonieae of laterally compressed curved emergences in Drčge's herbarium specimen. Living emergences of a seedling leaf are less laterally compressed. Living and herbarium emergences share a further unique detail: the rounded tip is uneven with projecting cells. As to the distribution, M. tenella is only known from the Bokkeveld escarpment (Western Cape, Baker 1897), whereas M. wittebergensis occurs in the Drakensberge eight degrees longitude further east in the Eastern Cape. As to the second species treated here, a closer investigation of a leaf and a withered fresh inflorescence showed that it is a new species too: Masso- nia sempervirens U.Müll.-Doblies, G.Milkuhn & D.Müll.-Doblies. The retired horticulturist, Gottfried Milkuhn (Dresden), had received this enigmatic remarkable evergreen Massonia species in 2007 from a Dutch succulent grower as "Whiteheadia jasminiflora " from Prince Albert (Western Cape) (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Habitat selection as a source of inter-specific differences in recruitment of two diadromous fish speciesFRESHWATER BIOLOGY, Issue 11 2008ROBIN HALE Summary 1For aquatic species with highly dispersive offspring, the addition of new individuals into an area (recruitment) is a key process in determining local population size so understanding the causes of recruitment variability is critical. While three general causative mechanisms have been identified (the supply of individuals, habitat selection and mortality), we have a limited understanding of how variation in each is generated, and the consequences this may have for the spatial and temporal distribution of recruits. 2We examined whether active habitat selection during settlement could be the cause of variability in populations of two diadromous fish species using a field survey and laboratory-based choice experiments. If larval behaviour is important, we predicted there would be inter-specific differences in abundance between sites during the survey, and that larvae would prefer water collected from sites with higher conspecific abundances during the experiments. 3During the field survey, significant differences were detected between two rivers (the Cumberland and Grey), with one species (Galaxias maculatus) found in higher abundances at one site (the Cumberland River) while comparable numbers of a closely related species (Galaxias brevipinnis) were caught at both sites. Laboratory choice experiments were conducted to determine whether larval preferences during settlement could be the cause of these differences. G. maculatus larvae showed a preference for freshwater over saltwater, indicating that the fish may be responding to reduced salinities around river mouths during settlement. The results of a second experiment were consistent with the notion that larval preferences could be the mechanism driving differences in the populations of the two rivers, with G. maculatus preferring water collected from the Cumberland River while G. brevipinnis did not prefer water from either river. 4These results demonstrate that active habitat selection may be important in establishing spatial patterns of larvae at settlement, and that multiple cues are likely to be involved. This study also demonstrates that the behaviours exhibited by individuals can strongly influence the structure and dynamics of populations of aquatic species with complex life cycles. [source] Public Health for the 21st Century: New Perspectives on Policy, Participation and Practice (2nd edn) , Edited by Judy Orme, Jane Powell, Pat Taylor and Melanie GreyHEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 1 2008Joyce Halliday No abstract is available for this article. [source] DISCIPLINING THE PROFESSIONAL: THE CASE OF PROJECT MANAGEMENT*JOURNAL OF MANAGEMENT STUDIES, Issue 6 2002DAMIAN HODGSON Despite its rapid growth in recent years, Project Management has received very little critical attention, particularly when compared to the more ,hyped' managerial fashions such as TQM (cf. Wilkinson and Willmott, 1995) and BPR (cf. Grey and Mitev, 1995; Grint, 1994). My intention in this paper is to critically examine the ongoing construction of Project Management as a professional discipline in modern organizations. Drawing on an understanding of ,discipline' based in Foucauldian work, I will briefly trace the historical construction of Project Management as a form of managerial knowledge, outlining the key models and techniques which make up contemporary Project Management. Through an empirical study of the articulation and reproduction of Project Management within two Financial Services institutions, the everyday construction of Project Management as an ,objective' and ,abstract' body of knowledge will be described. I then contrast this with the embodied and power-laden operation of Project Management, with disciplinary effects not only on those employees whose work is restructured in line with Project Management principles but equally upon self-professed Project Management professionals themselves. [source] Zane Grey: His Life, His Adventure, His WomenTHE JOURNAL OF AMERICAN CULTURE, Issue 1 2006Ray B. Browne No abstract is available for this article. [source] Co-operative learning for students with difficulties in learning: a description of models and guidelines for implementationBRITISH JOURNAL OF SPECIAL EDUCATION, Issue 3 2005Ellen Murphy As part of a larger study regarding the inclusion of children with disabilities in mainstream classroom settings, Ellen Murphy, of the D Clin Psych programme at NUI Galway, with Ian Grey and Rita Honan, from Trinity College, Dublin, reviewed existing literature on co-operative learning in the classroom. In this article, they identify four models of co-operative learning and specify the various components characteristic of each model. They review recent studies on co-operative learning with the aim of determining effectiveness. These studies generally indicate that co-operative learning appears to be more effective when assessed on measures of social engagement rather than academic performance. Finally, Ellen Murphy, Ian Grey and Rita Honan present their account of the factors that contribute to the successful implementation of co-operative learning for students with difficulties in learning. [source] Stege Grey, managing director, live | workBUSINESS STRATEGY REVIEW, Issue 3 2008Article first published online: 13 AUG 200 No abstract is available for this article. [source] Comparative in vitro study of the sealing efficiency of white vs grey ProRoot mineral trioxide aggregate formulas as apical barriersDENTAL TRAUMATOLOGY, Issue 2 2008Spyridon Stefopoulos Recently conventional grey MTA has been replaced by a new white MTA formula. The aim of this study was to compare the root canal adaptation of white MTA to that of grey MTA when used as an apical barrier in teeth with open apices. We also examined whether a previous calcium hydroxide intracanal medication affects MTA's sealing ability and investigated the ability to remove calcium hydroxide from the root canal walls. Forty-nine teeth were prepared in a manner to simulate a divergent open apex of immature teeth. Four teeth were used in a preliminary experiment to demonstrate the inefficacy of calcium hydroxide removal from the canal walls in teeth with open apices. Four groups of 10 teeth each were created: groups A and B were treated with calcium hydroxide intracanal medication and then received an apical plug of grey and white MTA respectively. Groups C and D received an apical plug of grey and white MTA respectively without previous intracanal medication. Four teeth served as negative and one as a positive control. The marginal adaptation and sealing ability of the apical barrier were tested by means of a dye tracer (basic fuchsine) after longitudinal sectioning. It was found that MTA apical barrier resisted displacement during gutta-percha condensation. Calcium hydroxide pretreatment, adversely affected white MTA sealing ability (P < 0.05). [source] Cerebral grey and white matter changes in mild cognitive impairment and Alzheimer's diseaseEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2009C. Luckhaus No abstract is available for this article. [source] Differences in grey and white matter atrophy in amnestic mild cognitive impairment and mild Alzheimer's diseaseEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2009M. L. F. Balthazar Background:, Grey matter (GM) atrophy has been demonstrated in amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (AD), but the role of white matter (WM) atrophy has not been well characterized. Despite these findings, the validity of aMCI concept as prodromal AD has been questioned. Methods:, We performed brain MRI with voxel-based morphometry analysis in 48 subjects, aiming to evaluate the patterns of GM and WM atrophy amongst mild AD, aMCI and age-matched normal controls. Results:, Amnestic mild cognitive impairment GM atrophy was similarly distributed but less intense than that of mild AD group, mainly in thalami and parahippocampal gyri. There were no difference between aMCI and controls concerning WM atrophy. In the mild AD group, we found WM atrophy in periventricular areas, corpus callosum and WM adjacent to associative cortices. Discussion:, We demonstrated that aMCI might be considered a valid concept to detect very early AD pathology, since we found a close proximity in the pattern of atrophy. Also, we showed the involvement of WM in mild AD, but not in aMCI, suggesting a combination of Wallerian degeneration and microvascular ischaemic disease as a plausible additional pathological mechanism for the discrimination between MCI and AD. [source] No change in the structure of the brain in migraine: a voxel-based morphometric studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2003M. S. Matharu Migraine is a common, disabling form of primary neurovascular headache. For most of the twentieth century it was regarded as a vascular headache whose primary pathophysiology lay in the cranial vasculature. Functional brain imaging using positron emission tomography has demonstrated activation of the rostral brain stem in acute migraine. Voxel-based morphometry is a new fully automated whole brain technique that is sensitive to subtle macroscopic and mesoscopic structural differences between groups of subjects. In this study 11 patients suffering from migraine with aura (10 females, one male: 23,52 years, mean 31); 11 controls (10 females, one male: 23,52, mean 31); 17 patients with migraine without aura (16 females, one male: 24,57, mean 34); 17 controls (16 females, one male: 24,57, mean 34) were imaged with high resolution volumetric magnetic resonance imaging. There was no significant difference in global grey or white matter volumes between either patients with migraine and controls, or patients with aura and without aura. This study did not show any global or regional macroscopic structural difference between patients with migraine and controls, with migraine sufferers taken as homogenous groups. If structural changes are to be found, other methods of phenotyping migraine, such as by genotype or perhaps treatment response, may be required to resolve completely whether there is some subtle structural change in the brain of patients with migraine. [source] The periaqueductal grey modulates sensory input to the cerebellum: a role in coping behaviour?EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2009Nadia L. Cerminara Abstract The paths that link the periaqueductal grey (PAG) to hindbrain motor circuits underlying changes in behavioural responsiveness to external stimuli are unknown. A major candidate structure for mediating these effects is the cerebellum. The present experiments test this directly by monitoring changes in size of cerebellar responses evoked by peripheral stimuli following activation of the PAG. In 22 anaesthetized adult Wistar rats, climbing fibre field potentials were recorded from the C1 zone in the paramedian lobule and the copula pyramidis of the cerebellar cortex evoked, respectively, by electrical stimulation of the ipsilateral fore- and hindlimb. An initial and a late response were attributable to activation of A, and A, peripheral afferents respectively (hindlimb onset latencies 16.9 and 23.8 ms). Chemical stimulation at physiologically-identified sites in the ventrolateral PAG (a region known to be associated with hyporeactive immobility) resulted in a significant reduction in size of both the A, and A, evoked field potentials (mean reduction relative to control ± SEM, 59 ± 7.5 and 66 ± 11.9% respectively). Responses evoked by electrical stimulation of the dorsal or ventral funiculus of the spinal cord were also reduced by PAG stimulation, suggesting that part of the modulation may occur at supraspinal sites (including at the level of the inferior olive). Overall, the results provide novel evidence of descending control into motor control centres, and provide the basis for future studies into the role of the PAG in regulating motor activity in different behavioural states and in chronic pain. [source] Differential galanin receptor-1 and galanin expression by 5-HT neurons in dorsal raphé nucleus of rat and mouse: evidence for species-dependent modulation of serotonin transmissionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2003Jari A. Larm Abstract Galanin and galanin receptors are widely expressed by neurons in rat brain that either synthesize/release and/or are responsive to, classical transmitters such as ,-aminobutyric acid, acetylcholine, noradrenaline, histamine, dopamine and serotonin (5-hydroxytryptamine, 5-HT). The dorsal raphé nucleus (DRN) contains , 50% of the 5-HT neurons in the rat brain and a high percentage of these cells coexpress galanin and are responsive to exogenous galanin in vitro. However, the precise identity of the galanin receptor(s) present on these 5-HT neurons has not been previously established. Thus, the current study used a polyclonal antibody for the galanin receptor-1 (GalR1) to examine the possible expression of this receptor within the DRN of the rat and for comparative purposes also in the mouse. In the rat, intense GalR1-immunoreactivity (IR) was detected in a substantial population of 5-HT-immunoreactive neurons in the DRN, with prominent receptor immunostaining associated with soma and proximal dendrites. GalR1-IR was also observed in many cells within the adjacent median raphé nucleus. In mouse DRN, neurons exhibited similar levels and distribution of 5-HT-IR to that in the rat, but GalR1-IR was undetectable. Consistent with this, galanin and GalR1 mRNA were also undetectable in mouse DRN by in situ hybridization histochemistry, despite the detection of GalR1 mRNA (and GalR1-IR) in adjacent cells in the periaqueductal grey and other midbrain areas. 5-HT neuron activity in the DRN is primarily regulated via 5-HT1A autoreceptors, via inhibition of adenylate cyclase and activation of inward-rectifying K+ channels. Notably, the GalR1 receptor subtype signals via identical mechanisms and our findings establish that galanin modulates 5-HT neuron activity in the DRN of the rat via GalR1 (auto)receptors. However, these studies also identify important species differences in the relationship between midbrain galanin and 5-HT systems, which should prompt further investigations in relation to comparative human neurochemistry and which have implications for studies of animal models of relevant neurological conditions such as stress, anxiety and depression. [source] Noxious Somatic Inputs to Hypothalamic-Midbrain Projection Neurones: a Comparison of the Columnar Organisation of Somatic and Visceral Inputs to the Periaqueductal Grey in the RatEXPERIMENTAL PHYSIOLOGY, Issue 2 2002D. M. Parry The induction of Fos protein was used to localise hypothalamic neurones activated by noxious somatic stimulation. This was combined with retrograde transport of fluorescent latex microspheres from identified ,pressor' and ,depressor' sites in the dorsolateral/lateral or ventrolateral columns of the periaqueductal grey (PAG). Fos-positive neurones were found throughout the rostral hypothalamus. Of those neurones activated by noxious somatic stimuli that projected to the PAG all but one was retrogradely labelled from sites that included the lateral column. Only one neurone was double labelled following injection of tracer at a depressor site in the ventrolateral PAG. This is in marked contrast to visceroresponsive hypothalamic neurones, a larger proportion of which project to the PAG and which, as reported previously, preferentially target depressor sites in the ventrolateral sector. These results are discussed in relation to the roles of the anterior hypothalamus and the different functional columns of the PAG in co-ordinating autonomic and sensory functions in response to nociceptive inputs originating in different peripheral domains. [source] C-Nociceptor Activation of Hypothalamic Neurones and the Columnar Organisation of Their Projections to the Periaqueductal Grey in the RatEXPERIMENTAL PHYSIOLOGY, Issue 2 2002B. M. Lumb The induction of Fos protein was used to localise hypothalamic neurones activated by ramps of noxious skin heating delivered at a rate of 2.5 °C s,1 to preferentially activate C-nociceptors. This was combined with retrograde transport of cholera toxin subunit B from identified ,pressor' and ,depressor' sites in the dorsolateral/lateral or the ventrolateral columns of the periaqueductal grey. Fos-positive neurones were found throughout the rostral hypothalamus. Despite this wide distribution, those neurones double labelled retrogradely from the periaqueductal grey were focused in the lateral area of the anterior hypothalamus. More than 20% of Fos-positive neurones in this region projected to depressor sites in the ventrolateral periaqueductal grey, and 10% projected to its dorsolateral/lateral sector. These results are discussed in relation to the peripheral inputs to hypothalamic-midbrain pathways and their role in the cardiovascular responses to different components of the pain signal. [source] Localized ductile thrusting north of the Variscan Front, Ross Island, southwest IrelandGEOLOGICAL JOURNAL, Issue 1 2003Paul A. M. Nex Abstract Two thrusts occur on Ross Island: the Head of Ross Thrust and the more southerly Ross Island Thrust. These lie to the north of the Killarney,Mallow Fault (KMF), the boundary frequently interpreted as the Variscan Front. The Ross Island Thrust, exposed in outcrop and in seven borehole cores, has emplaced dark blue,grey limestones of the Courceyan Ballysteen Formation over pale grey,brown Rockfield Limestone Formation of Chadian,Holkerian age. These lithologies at Ross Island exhibit a continuum of deformation at both the micro- and macro-scale, beginning with the generation of a spaced cleavage, formed during layer parallel shortening, that was subsequently rotated into parallelism with fold axial planes. Extensional microstructures are predominant in thin section and are associated with attenuation of the fold limb. Calcite veins are also attenuated and lie parallel to a mylonitic fabric close to the thrust plane. Lithological boundaries, the prominent pressure solution cleavage and the southerly dipping limb of an asymmetrical antiform are all parallel and form a composite planar anisotropy. This has controlled the location of the ductile Ross Island Thrust, which formed during the attenuation and shearing of a common fold limb. Ductile thrusts within the limestones at Ross Island contrast with the reactivation of basin-margin extensional faults further to the south along the major KMF. The Ross Island Thrust is considered to result from deformation ahead of the major northerly propagating Variscan décollement thrust and does not necessitate a continuous décollement structure north of the KMF. Mineralization at Ross Island exhibits remobilization associated with the formation of a pressure-solution cleavage and probably pre-dates thrusting. Copyright © 2003 John Wiley & Sons, Ltd. [source] Coronary heart disease is associated with regional grey matter volume loss: implications for cognitive function and behaviourINTERNAL MEDICINE JOURNAL, Issue 7 2008O. P. Almeida Abstract Coronary heart disease (CHD) has been associated with impaired cognition, but the mechanisms underlying these changes remain unclear. We designed this study to determine whether adults with CHD show regional brain losses of grey matter volume relative to controls. We used statistical parametric mapping (SPM5) to determine regional changes in grey matter volume of T1 -weighted magnetic resonance images of 11 adults with prior history of myocardial infarction relative to seven healthy controls. All analyses were adjusted for total grey and white matter volume, age, sex and handedness. CHD participants showed a loss of grey matter volume in the left medial frontal lobe (including the cingulate), precentral and postcentral cortex, right temporal lobe and left middle temporal gyrus, and left precuneus and posterior cingulate. CHD is associated with loss of grey matter in various brain regions, including some that play a significant role in cognitive function and behaviour. The underlying causes of these regional brain changes remain to be determined. [source] Unsteady free convection,radiation flow over a vertical wall embedded in a porous mediumINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2008Joaquķn Zueco Abstract A numerical solution for the transient two-dimensional free convection flow of viscous dissipative fluid over an infinite vertical plate through a porous medium bounded, taking into account the thermal radiation, is analysed. The fluid is grey, and acts as a radiation emitting and absorbing (but non-scattering) medium. The influence of the non-dimensional parameters such as the Forchheimer coefficient (Fo), the permeability parameter (P), the Eckert number (Ec) and the radiation parameter (R) on the velocity, temperature, Nusselt number and on the time taken to reach the steady state is studied. The possibility of non-Darcy flow is also analysed. The numerical method employed, network simulation method, is based on an electro-thermal analogy and permits the direct visualization and evolution of the local and/or integrated transport variables (velocities, temperatures and fluxes) at any point or section of the medium. The numerical solutions of this work have been compared with the existing information in the literature with good agreement. Copyright © 2007 John Wiley & Sons, Ltd. [source] The functional neuroanatomy of geriatric depressionINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2009Gwenn S. Smith Abstract Objective Positron Emission Tomography (PET) studies of cerebral glucose metabolism have demonstrated sensitivity in evaluating the functional neuroanatomy of treatment response variability in depression, as well as in the early detection of functional changes associated with incipient cognitive decline. The evaluation of cerebral glucose metabolism in late life depression may have implications for understanding treatment response variability, as well as evaluating the neurobiological basis of depression in late life as a risk factor for dementia. Methods Sixteen patients with geriatric depression and 13 comparison subjects underwent resting PET studies of cerebral glucose metabolism, as well as magnetic resonance (MR) imaging scans to evaluate brain structure. Results Cerebral glucose metabolism was elevated in geriatric depressed patients relative to comparison subjects in anterior (right and left superior frontal gyrus) and posterior (precuneus, inferior parietal lobule) cortical regions. Cerebral atrophy (increased cerebrospinal fluid [CSF] and decreased grey and white matter volumes) were observed in some of these regions, as well. Regional cerebral metabolism was positively correlated with severity of depression and anxiety symptoms. Conclusions In contrast to decreased metabolism observed in normal aging and neurodegenerative conditions such as Alzheimer's disease, cortical glucose metabolism was increased in geriatric depressed patients relative to demographically matched controls, particularly in brain regions in which cerebral atrophy was observed, which may represent a compensatory response. Copyright © 2009 John Wiley & Sons, Ltd. [source] The superior colliculus of the camel: a neuronal-specific nuclear protein (NeuN) and neuropeptide studyJOURNAL OF ANATOMY, Issue 2 2006E. P. K. Mensah-Brown Abstract In this study we examined the superior colliculus of the midbrain of the one-humped (dromedary) camel, Camelus dromedarius, using Nissl staining and anti-neuronal-specific nuclear protein (NeuN) immunohistochemistry for total neuronal population as well as for the enkephalins, somatostatin (SOM) and substance P (SP). It was found that, unlike in most mammals, the superior colliculus is much larger than the inferior colliculus. The superior colliculus is concerned with visual reflexes and the co-ordination of head, neck and eye movements, which are certainly of importance to this animal with large eyes, head and neck, and apparently good vision. The basic neuronal architecture and lamination of the superior colliculus are similar to that in other mammals. However, we describe for the first time an unusually large content of neurons in the superior colliculus with strong immunoreactivity for met-enkephalin, an endogenous opioid. We classified the majority of these neurons as small (perimeters of 40,50 µm), and localized diffusely throughout the superficial grey and stratum opticum. In addition, large pyramidal-like neurons with perimeters of 100 µm and above were present in the intermediate grey layer. Large unipolar cells were located immediately dorsal to the deep grey layer. By contrast, small neurons (perimeters of 40,50 µm) immunopositive to SOM and SP were located exclusively in the superficial grey layer. We propose that this system may be associated with a pain-inhibiting pathway that has been described from the periaqueductal grey matter, juxtaposing the deep layers of the superior colliculus, to the lower brainstem and spinal cord. Such pain inhibition could be important in relation to the camel's life in the harsh environment of its native deserts, often living in very high temperatures with no shade and a diet consisting largely of thorny branches. [source] Ultrastructure of the placenta of the tammar wallaby, Macropus eugenii: comparison with the grey short-tailed opossum, Monodelphis domesticaJOURNAL OF ANATOMY, Issue 2 2002Claudia Freyer Abstract The ultrastructure of the tammar placenta was studied throughout pregnancy. The uterine epithelium grows from a columnar to an enlarged, undulating epithelium between early gestation and mid-gestation when the shell coat that surrounds the marsupial conceptus ruptures. Trophectoderm and uterine epithelium do not form syncytia, nor does invasion of the endometrium occur at any stage of pregnancy. Uterine secretion is provided to both the bilaminar and the trilaminar side of the yolk sac placenta up to birth. Fenestrations, abundant vesicles and lumenal processes of maternal capillaries, as well as deep basal folds of the uterine epithelium, suggest that there is transfer of hemotrophes adjacent to both parts of the yolk sac. In contrast, in the grey short-tailed opossum, these structures are lacking. The yolk sacs of adjacent embryos fuse to form a common yolk sac cavity, thus losing most of the bilaminar yolk sac. The bilaminar and trilaminar components of the yolk sac placenta of the tammar are less different in structure and function than those of the grey short-tailed opossum, but both types are fully functional placentas. The extended secretory phase of the tammar uterus and the maternal recognition of early pregnancy appear to be derived characters of macropodid marsupials. [source] Description of a new Lake Tanganyikan cichlid fish of the genus Cyprichromis(Perciformes: Cichlidae) with a note on sexual dimorphismJOURNAL OF FISH BIOLOGY, Issue SB 2006T. Takahashi Cyprichromis coloratus, a new cichlid species, is described based on 41 type specimens from the Zambian coast of Lake Tanganyika. It differs from Cyprichromis microlepidotus by having fewer scales in the longitudinal line (41,44 v. 59,70 in C. microlepidotus) and upper lateral line (31,36 v. 47,59), from Cyprichromis leptosoma by more dorsal-fin spines (14,15 v. 11,13 in C. leptosoma) and longitudinal line scales (41,44 v. 38,40), from Cyprichromis pavo by fewer dorsal-fin spines and soft rays (29,31, usually 30, in total v. 30,32, usually 31, in C. pavo), and from Cyprichromis zonatus by shallower body depth [24·0,28·5 (26·4 ± 1·1)% of standard length v. 24·5,30·5 (28·4 ± 1·3)% in C. zonatus] and smaller eye [eye length 25·2,30·9 (27·2 ± 1·1)% of head length v. 27·9,33·3 (30·2 ± 1·2)%]. The new species is also separable from C. microlepidotus, C. pavo and C. zonatus by absence of distinct small spots on the body (v. pearl grey and yellowish small spots along scale rows on body at least in males of C. microlepidotus and C. pavo), its distinct dichromatism (particularly on the caudal fin) between males of the same population (v. dichromatism absent in C. zonatus) and absence of vertical bands (v. three or four distinct vertical bands beneath dorsal fin base in live males of C. zonatus). Cyprichromis coloratus n. sp. also exhibits sexual dimorphism, females having a larger head and males having longer pelvic fin, differences which are discussed in relation to reproductive behaviour. A key to the five species of Cyprichromis is included. A lectotype is designated for Cyprichromis leptosoma. [source] Role of fluids in the metamorphism of the Alpine Fault Zone, New ZealandJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2001J. K. Vry Abstract Models of fluid/rock interaction in and adjacent to the Alpine Fault in the Hokitika area, South Island, New Zealand, were investigated using hydrogen and other stable isotope studies, together with field and petrographic observations. All analysed samples from the study area have similar whole-rock ,D values (,DWR = ,56 to ,30,, average = ,45,, n = 20), irrespective of rock type, degree of chloritization, location along the fault, or across-strike distance from the fault in the garnet zone. The green, chlorite-rich fault rocks, which probably formed from Australian Plate precursors, record nearly isothermal fluid/rock interaction with a schist-derived metamorphic fluid at high temperatures near 450,500°C (,D of water in equilibrium with the green fault rocks (,DH2O, green) ,,,18,; ,D of water in equilibrium with the greyschists and greyschist-derived mylonites (,DH2O, grey) , ,19, at 500°C; ,DH2O, green , ,17,; ,DH2O, grey , ,14, at 450°C). There is no indication of an influx of a meteoric or mantle-derived fluid in the Alpine Fault Zone in the study area. The Alpine Fault Zone at the surface shows little evidence of late-stage retrogression or veining, which might be attributed to down-temperature fluid flow. It is probable that prograde metamorphism in the root zone of the Southern Alps releases metamorphic fluids that at some region rise vertically rather than following the trace of the Alpine Fault up to the surface, owing to the combined effects of the fault, the disturbed isotherms under the Southern Alps, and the brittle,ductile transition. Such fluids could mix with meteoric fluids to deposit quartz-rich, possibly gold-bearing veins in the region c. 5,10 km back from the fault trace. These results and interpretations are consistent with interpretations of magnetotelluric data obtained in the South Island GeopHysical Transects (SIGHT) programme. [source] Modifications of the iron,neuromelanin system in Parkinson's diseaseJOURNAL OF NEUROCHEMISTRY, Issue 4 2006Mauro Fasano Abstract Parkinson's disease is a common neurodegenerative disorder with a mainly sporadic aetiology, although a number of monogenic familiar forms are known. Most of the motor symptoms are due to selective depletion of dopaminergic, neuromelanin-containing neurones of the substantia nigra pars compacta. Neuromelanin is the dark insoluble macromolecule that confers the black (substantia nigra) or grey (locus coeruleus) colour to monoaminergic basal ganglia. In particular, nigral neurones are pigmented because of the accumulation of by-products of oxidative metabolism of the neurotransmitter dopamine. The occurrence of dopamine (and all the enzymatic machinery required for dopamine synthesis, re-uptake and disposal) and neuromelanin, and a large amount of iron ions that interact with them, makes dopaminergic nigral neurones peculiarly susceptible to oxidative stress conditions that, in turn, may become amplified by the iron,neuromelanin system itself. In this mini-review we describe biophysical evidence for iron,neuromelanin modifications that support this hypothesis. Furthermore, we discuss the formation of the covalent linkage between ,-synuclein and neuromelanin from the early stages of the disease. [source] The solubility of ,-synuclein in multiple system atrophy differs from that of dementia with Lewy bodies and Parkinson's diseaseJOURNAL OF NEUROCHEMISTRY, Issue 1 2001Bruce C. V. Campbell Intracellular inclusions containing ,-synuclein (,SN) are pathognomonic features of several neurodegenerative disorders. Inclusions occur in oligodendrocytes in multiple system atrophy (MSA) and in neurons in dementia with Lewy bodies (DLB) and Parkinson's disease (PD). In order to identify disease-associated changes of ,SN, this study compared the levels, solubility and molecular weight species of ,SN in brain homogenates from MSA, DLB, PD and normal aged controls. In DLB and PD, substantial amounts of detergent-soluble and detergent-insoluble ,SN were detected compared with controls in grey matter homogenate. Compared with controls, MSA cases had significantly higher levels of ,SN in the detergent-soluble fraction of brain samples from pons and white matter but detergent-insoluble ,SN was not detected. There was an inverse correlation between buffered saline-soluble and detergent-soluble levels of ,SN in individual MSA cases suggesting a transition towards insolubility in disease. The differences in solubility of ,SN between grey and white matter in disease may result from different processing of ,SN in neurons compared with oligodendrocytes. Highly insoluble ,SN is not involved in the pathogenesis of MSA. It is therefore possible that buffered saline-soluble or detergent-soluble forms of ,SN are involved in the pathogenesis of other ,SN-related diseases. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||