30 resultados para Pyramidal Tracts
Resumo:
Throughout the reign of Elizabeth I, a steady stream of tracts appeared in English print to vindicate the succession of the most prominent contenders, Mary and James Stuart of Scotland. This article offers a comprehensive account of the polemical battle between the supporters and opponents of the Stuarts, and further identifies various theories of English kingship, most notably the theory of corporate kingship, developed by the Stuart polemicists to defend the Scottish succession. James's accession to the English throne in March 1603 marked the protracted end of the debate over the succession. The article concludes by suggesting that, while powerfully renouncing the opposition to his succession, over the course of his attempt to unify his two kingdoms, James and his supporters ultimately departed from the polemic of corporate kingship, for a more assertive language of kingship by natural and divine law.
Resumo:
Salmonella enterica serovar Agona has caused multiple food-borne outbreaks of gastroenteritis since it was first isolated in 1952. We analyzed the genomes of 73 isolates from global sources, comparing five distinct outbreaks with sporadic infections as well as food contamination and the environment. Agona consists of three lineages with minimal mutational diversity: only 846 single nucleotide polymorphisms (SNPs) have accumulated in the non-repetitive, core genome since Agona evolved in 1932 and subsequently underwent a major population expansion in the 1960s. Homologous recombination with other serovars of S. enterica imported 42 recombinational tracts (360 kb) in 5/143 nodes within the genealogy, which resulted in 3,164 additional SNPs. In contrast to this paucity of genetic diversity, Agona is highly diverse according to pulsed-field gel electrophoresis (PFGE), which is used to assign isolates to outbreaks. PFGE diversity reflects a highly dynamic accessory genome associated with the gain or loss (indels) of 51 bacteriophages, 10 plasmids, and 6 integrative conjugational elements (ICE/IMEs), but did not correlate uniquely with outbreaks. Unlike the core genome, indels occurred repeatedly in independent nodes (homoplasies), resulting in inaccurate PFGE genealogies. The accessory genome contained only few cargo genes relevant to infection, other than antibiotic resistance. Thus, most of the genetic diversity within this recently emerged pathogen reflects changes in the accessory genome, or is due to recombination, but these changes seemed to reflect neutral processes rather than Darwinian selection. Each outbreak was caused by an independent clade, without universal, outbreak-associated genomic features, and none of the variable genes in the pan-genome seemed to be associated with an ability to cause outbreaks. © 2013 Achtman et al
Resumo:
Background: Rapid compensatory arm reactions represent important response strategies following an unexpected loss of balance. While it has been assumed that early corrective actions arise largely from sub-cortical networks, recent findings have prompted speculation about the potential role of cortical involvement. To test the idea that cortical motor regions are involved in early compensatory arm reactions, we used continuous theta burst stimulation (cTBS) to temporarily suppress the hand area of primary motor cortex (M1) in participants prior to evoking upper limb balance reactions in response to whole body perturbation. We hypothesized that following cTBS to the M1 hand area evoked EMG responses in the stimulated hand would be diminished. To isolate balance reactions to the upper limb participants were seated in an elevated tilt-chair while holding a stable handle with both hands. The chair was held vertical by a magnet and was triggered to fall backward unpredictably. To regain balance, participants used the handle to restore upright stability as quickly as possible with both hands. Muscle activity was recorded from proximal and distal muscles of both upper limbs.
Results: Our results revealed an impact of cTBS on the amplitude of the EMG responses in the stimulated hand muscles often manifest as inhibition in the stimulated hand. The change in EMG amplitude was specific to the target hand muscles and occasionally their homologous pairs on the non-stimulated hand with no consistent effects on the remaining more proximal arm muscles.
Conclusions: Present findings offer support for cortical contributions to the control of early compensatory arm reactions following whole-body perturbation.
Resumo:
This paper presents novel advances on the deformation behaviour of polycrystalline and single crystal silicon using molecular dynamics (MD) simulation and validation of the same via nanoindentation experiments. In order to unravel the mechanism of deformation, four simulations were performed: Indentation of polycrystalline silicon substrate with a (i) Berkovich pyramidal and a (ii) spherical (arc) indenter, and indentation of a single crystal silicon substrate with these two indenters. The simulation results reveal that high pressure phase transformation (HPPT) in silicon (Si-I to Si-II phase transformation) occurred in all cases, however, its extent and the manner in which it occurred differed significantly between polycrystalline silicon and single crystal silicon, and was the main driver of differences in nanoindentation deformation behaviour between the two types of silicon. An interesting observation was that in polycrystalline silicon, the HPPT was observed to occur preferentially along the grain boundaries than across the grain boundaries. An automated dislocation extraction algorithm (DXA) revealed no dislocations in the deformation zone, suggesting HPPT to be the primary mechanism in inducing plasticity in silicon.
Resumo:
Diffusion tensor imaging (DTI) studies have identified changes in white matter tracts in schizophrenia patients and those at high risk of transition. Schizotypal samples represent a group on the schizophrenia continuum that share some aetiological risk factors but without the confounds of illness. The aim of the current study was to compare tract microstructural coherence as measured by
fractional anisotropy (FA) between 12 psychometrically defined schizotypes and controls. We investigated bilaterally the uncinate and arcuate fasciculi (UF and AF) via a probabilistic tractography algorithm (PICo), with FA values compared between groups. Partial correlations were also examined between measures of subclinical hallucinatory/delusional experiences and FA values. High schizotypes
were found to have significantly higher FA values in bilateral UF only, but failed to reach significance in each hemisphere. In the whole sample there was a positive correlation between increasing FA values and measures of hallucinatory experience in the right AF. These findings suggest subtle changes in microstructural coherence are present in schizotypes. Correlations between mild hallucinatory experience and increasing FA values could indicate increasing coherence could be associated with symptom formation.
Resumo:
The title compound, [Ni2Cl2(C9H10NO2)(2)]center dot CH3OH, is a dinuclear unit built up by two nickel(II) complexes, bridged by two Cl atoms. The coordination geometry around each Ni-II atom can be considered as distorted square-pyramidal, with the tridendate chelate Schiff base ligands coordinating in a trans conformation through their imine N atom and phenoxy and alkoxy O atoms.
Resumo:
Purpose: Persistence of urinary incontinence post acquired brain injury (ABI) carries important prognostic significance. We undertook to document the incidence of urinary incontinence, its management and complications in rehabilitation inpatients following ABI and to assess adherence to post ABI bladder management guidelines.
Method: A retrospective chart survey of a convenience sample of consecutive admissions to two adult neurorehabilitation units Forster Green Hospital, Belfast, and the Scottish Brain Injury Rehabilitation Service, Edinburgh (SBIRSE). Bladder continence and management on transfer to and discharge from rehabilitation, trial removal of catheter, use of bladder drill, ultrasound investigation, anticholinergic medication and complications were recorded.
Results: One hundred and forty six patients were identified. Seventy-seven (52.7%) were independent and continent of urine at rehabilitation admission and 109 (74.7%) on discharge. In all, 13 patients had urinary tract infection, 7 had urethral stricture and 1 developed haematuria whilst catheterised. Ultrasound of renal tracts was underused. Trial removal of catheter after transfer to rehabilitation occurred at a median of 10 days.
Conclusions: Urinary continence was achieved in almost half of incontinent ABI patients during rehabilitation. There is potential for increased use of investigation of the renal tracts. Rehabilitation physicians should consider urethral stricture in the management of continence post ABI.
Implications for Rehabilitation:
- Persisting urinary incontinence post ABI is associated with increased morbidity.
- Urethral stricture is an under-recognised complication after ABI and should be considered as a potential cause of incontinence in this patient group.
- Gains in urinary continence are seen in patients post ABI, managed with various interventions.
- Goal setting offers an opportunity to focus on bladder management rather than simply continence and may allow improvement in rate of appropriate investigation
Resumo:
Phalloidin fluorescence technique, enzyme cytochemistry and immunocytochemistry in conjunction with confocal scanning laser microscopy were used for the first time to describe the nervous and muscle systems of the viviparous monogenean parasite, Gyrodactylus rysavyi inhabiting the gills and skin of the Nile catfish Clarias gariepinus. The body wall muscles are composed of an outer layer of circular fibres, an intermediate layer of paired longitudinal fibres and an inner layer of well-spaced bands of diagonal fibres arranged in two crossed directions. The musculature of the pharynx, intestine, reproductive tract and the most prominent muscles of the haptor were also described. Two characteristic muscular pads were found lying in the anterior region of the haptor in close contact with the hamuli. To each one of these pads, a group of ventral extrinsic muscles was connected. The role of this ventral extrinsic muscle in the body movement was discussed. The mechanism operating the marginal hooklets was also discussed. The central nervous system (CNS) consists of paired cerebral ganglia from which three pairs of longitudinal ventral, lateral and dorsal nerve cords arise. The nerve cords are connected at intervals by many transverse connectives. The CNS is better developed ventrally than dorsally or laterally and it has the highest reactivity for all neuroactive substances examined. Both the central and the peripheral nervous system (PNS) are bilaterally symmetrical. Structural and functional correlates of the neuromusculature of the pharynx, haptor and reproductive tracts were explained. The results implicated acetylcholine, FMRFamide-related peptides (FaRPs) and serotonin in sensory and motor function. The results were compared with those of the monogeneans Macrogyrodactylus clarii and M. congolensis inhabiting the gills and skin respectively of the same host fish C. gariepinus.
Resumo:
Phalloidin fluorescence technique, enzyme cytochemistry and immunocytochemistry, in conjunction with confocal scanning laser microscopy, were used to describe the neuromusculature of the monogenean skin parasite Macrogyrodactylus congolensis from the Nile catfish Clarias gariepinus. The body wall muscles are composed of an outer layer of compactly arranged circular fibres, an intermediate layer of paired longitudinal fibres and an inner layer of well-spaced bands of diagonal fibres arranged in two crossed directions. The central nervous system consists of paired cerebral ganglia from which three pairs of longitudinal ventral, lateral and dorsal nerve cords arise. The nerve cords are connected at intervals by many transverse connectives. Both central and peripheral nervous systems are bilaterally symmetrical and better developed ventrally than laterally and dorsally. Structural and functional correlates of the neuromusculature of the pharynx, haptor and reproductive tracts were examined. Results implicate acetylcholine, FMRFamide-related peptides and serotonin in sensory and motor function. The results were compared with those of Macrogyrodactylus clarii, a gill parasite of the same host fish C. gariepinus.
Resumo:
Phalloidin fluorescence technique, enzyme cytochemistry and immunocytochemistry in conjunction with confocal scanning laser microscopy have been used for the first time to describe the nervous and muscle systems of the viviparous monogenean gill parasite, Macrogyrodactylus clarii. The gross spatial arrangement of muscle and associated cholinergic, peptidergic and aminergic innervations has been examined. The central nervous system (CNS) consists of paired cerebral ganglia from which emanate three pairs of longitudinal ventral, lateral and dorsal nerve cords, connected at intervals by transverse connectives. The CNS is better developed ventrally than dorsally or laterally, and has the strongest reactivity for all neuroactive substances examined. Structural and functional correlates of the neuromusculature of the pharynx, haptor and reproductive tracts have been examined. Results implicate acetylcholine, FMRFamide-related peptides (FaRPs) and serotonin in sensory and motor function in this monogenean, although confirmatory physiological data are obviously required.
Resumo:
Human respiratory syncytial virus (HRSV) is the most important viral cause of severe respiratory tract disease in infants. Two subgroups (A and B) have been identified, which cocirculate during, or alternate between, yearly epidemics and cause indistinguishable disease. Existing in vitro and in vivo models of HRSV focus almost exclusively on subgroup A viruses. Here, a recombinant (r) subgroup B virus (rHRSV(B05)) was generated based on a consensus genome sequence obtained directly from an unpassaged clinical specimen from a hospitalized infant. An additional transcription unit containing the gene encoding enhanced green fluorescent protein (EGFP) was introduced between the phosphoprotein and matrix genes (position 5) of the genome to generate rHRSV(B05)EGFP(5). The recombinant viruses replicated efficiently in both HEp-2 cells and in well-differentiated normal human bronchial cells grown at air-liquid interface. Intranasal infection of cotton rats (Sigmodon hispidus) resulted in high numbers of EGFP(+) cells in epithelia of the nasal septum and conchae. When administered in a relatively large inoculum volume, the virus also replicated efficiently in bronchiolar epithelial cells and spread extensively in both the upper and lower respiratory tracts. Virus replication was not observed in ciliated epithelial cells of the trachea. This is the first virulent rHRSV strain with the genetic composition of a currently circulating wild-type virus. In vivo tracking of infected cells by means of EGFP fluorescence in the absence of cytopathic changes increases the sensitivity of virus detection in HRSV pathogenesis studies.
IMPORTANCE
Virology as a discipline has depended on monitoring cytopathic effects following virus culture in vitro. However, wild-type viruses isolated from patients often do not cause significant changes to infected cells, necessitating blind passage. This can lead to genetic and phenotypic changes and the generation of high-titer, laboratory-adapted viruses with diminished virulence in animal models of disease. To address this, we determined the genome sequence of an unpassaged human respiratory syncytial virus from a sample obtained directly from an infected infant, assembled a molecular clone, and recovered a wild-type recombinant virus. Addition of a gene encoding enhanced green fluorescent protein allowed this wild-type virus to be tracked in primary human cells and living animals in the absence of significant cytopathic effects. Imaging of fluorescent cells proved to be a highly valuable tool for monitoring the spread of virus and may help improve assays for evaluating novel intervention strategies.
Resumo:
In recent years, the native woodlands of Europe, including those of Britain and Ireland, have increasingly come under threat from a range of biotic and abiotic factors, and are therefore a conservation priority demanding careful management in order to realise their inherent ecological and cultural benefits. Because the distribution of genetic variation across populations and regions is increasingly considered an important component of woodland management, we carried out a population genetic analysis on black alder (Alnus glutinosa) across Northern Ireland in order to inform “best practice” strategies. Our findings suggest that populations harbour high levels of genetic diversity, with very little differentiation between populations. Significant F IS values were observed in over half of the populations analysed, however, which could reflect inbreeding as a result of the patchy occurrence of alder in Northern Ireland, with scattered, favourable damp habitats being largely isolated from each other by extensive tracts of farmland. Although there is no genetic evidence to support the broad-scale implementation of tree seed zones along the lines of those proposed for native woodlands in Great Britain, we suggest that the localised occurrence of rare chloroplast haplotypes should be taken into account on a case-by-case basis. This, coupled with the identification of populations containing high genetic diversity and that are broadly representative of the region as a whole, will provide a sound genetic basis for woodland management, both in alder and more generally for species that exhibit low levels of genetic differentiation.
Resumo:
In 1858, a volume entitled Midnight Scenes and Social Photographs – being sketches of life in the streets, wynds and dens of the city of Glasgow was published under the pseudonym of ‘Shadow’ by Alexander Brown, a Glaswegian flâneur and reformer. Its frontispiece is an etching which depicts a theatre-like proscenium arch whose curtains have been withdrawn to reveal to the audience all the poverty, destitution and disorder that one was likely to find after dark in the insalubrious quarters of the city. At the extreme left-hand side, partly obscured by the curtain a silhouetted figure stands behind an unwieldy camera perched on a tripod. Distinctly unaffected by the mêlée, an arm is calmly raised and a finger precisely arched in the moment before the shutter is clicked and the scene committed to record. The volume, however, relies exclusively on textual descriptions to evoke the underside of the city and contains no photographs at all. Instead, the use of the word photograph in the title can be understood as a metaphor for detached scientific objectivity, a quality much celebrated by nineteenth-century reformers and investigators of social ills. As it happened, a decade after Shadow disappeared into the labyrinthine back-lands of Old Town Glasgow, he was followed there by a real photographer. In 1868, Thomas Annan was commissioned by the City Improvements Trust to take photographs of the Old Town in its last moments of existence before it was pulled down under a series of legislative acts. But perhaps paradoxically, given Shadow’s faith in the analytical properties of photography, Annan’s work seems to refute much of the material contained in Midnight Scenes and other similar tracts. Instead of the dens, shebeens, labyrinths and rowdy crowds described by Shadow, Annan’s depictions of the Old Town convey a static, calm environment, one which is often sparsely inhabited by a curious but apparently orderly population.
Taking account of the sensational tendencies of many reformists’ texts, this paper investigates the discrepancies between the two representations, focussing in particular on the constraints which operated on Annan during his commission. It argues that Annan’s compositions – which became very influential on other 19th century photographers of everyday life such as John Thomson or Jacob Riis – far from being dispassionate analytical works, emerged as a result of a matrix of factors which included: photographic and artistic precedents; Annan’s own predilections as a photographer; technological limitations; the nature of the commission from the City Improvements Trust and political climate in which it was given; the medieval urban fabric in which he had to operate; and, perhaps, most importantly, the identity of the Old Towns inhabitants themselves.
Resumo:
They’re cheap. They’re in every settlement of significance in Britain, Ireland and elsewhere. We all use them but perhaps do not always admit to it. Especially, if we are architects.
Over the past decades Aldi/Lidl low cost supermarkets have escaped from middle Europe to take over large tracts of the English speaking world remaking them according to a formula of mass-produced sheds, buff-coloured cobble-lock car parks, logos in primary colours, bare-shelves and eclectic special offers. Response within architectural discourse to this phenomenon has been largely one of indifference and such places remain, perhaps reiterating Pevsner’s controversial insights into the bicycle shed, on the peripheries of what we might term architecture. This paper seeks to explore the spatial complexities of the discount supermarket and in doing so open up a discussion on the architecture of cheapness. As a road-map, it takes former managing director Dieter Brandes’ treatise on the Aldi formula, Bare Essentials: the Aldi Way to Retailing, and investigates the strategies through which economic exigencies manifest themselves in a series of spatial tactics which involve building. Central to this is the idea of architecture as system rather than form and, in Aldi/Lidl’s case, the result of a spatial network of flows. To understand the architecture of the supermarket, then, it is necessary to measure the times and spaces of supply across the scales of intersection between global and local.
Evaluating the energy, economy and precision of such systems challenges the liminal position of the commercial, the placeless and especially the cheap within architectural discourse. As is well known, architectures of mass-production and prefabrication and their origins exercised modernist thinkers such as Sigfried Giedion and Walter Gropius in the early twentieth century and has undergone a resurgence in recent times. Meanwhile, the mapping of the hitherto overlooked forms and iconography of commerce in Learning from Las Vegas (1971) was extended by Rem Koolhaas et al into an investigation of the technologies, systems and precedents of retail in the Harvard Design School Guide to Shopping, thirty years later in 2001. While obviously always a criteria for building, to find writings on architecture which explicitly celebrate cheapness as a design virtue or, indeed, even iterate the word cheap is more difficult. Walter Gropius’ essay ‘How can we build cheaper, better, more attractive houses?’ (1927), however, situates the cheap within the discussions – articulated, amongst others, by Karl Teige and Bruno Taut – surrounding the minimal dwelling and the moral benefits of absence of the 1920s and 30s.
In our contemporary age of heightened consumption, it is perhaps fitting that an architecture of bare essentials is defined in retail rather than in housing, a commercial existenzminimum where the Miesian paradox of ‘less is more’ is resold as a paradigm of ‘more for less’ in the ubiquitous yet overlooked architectures of the discount supermarket.
Resumo:
β-amyloid1-42 (Aβ1-42) is a major endogenous pathogen underlying the aetiology of Alzheimer's disease (AD). Recent evidence indicates that soluble Aβ oligomers, rather than plaques, are the major cause of synaptic dysfunction and neurodegeneration. Small molecules that suppress Aβ aggregation, reduce oligomer stability or promote off-pathway non-toxic oligomerization represent a promising alternative strategy for neuroprotection in AD. MRZ-99030 was recently identified as a dipeptide that modulates Aβ1-42 aggregation by triggering a non-amyloidogenic aggregation pathway, thereby reducing the amount of intermediate toxic soluble oligomeric Aβ species. The present study evaluated the relevance of these promising results with MRZ-99030 under pathophysiological conditions i.e. against the synaptotoxic effects of Aβ oligomers on hippocampal long term potentiation (LTP) and two different memory tasks. Aβ1-42 interferes with the glutamatergic system and with neuronal Ca2+ signalling and abolishes the induction of LTP. Here we demonstrate that MRZ-99030 (100–500 nM) at a 10:1 stoichiometric excess to Aβ clearly reversed the synaptotoxic effects of Aβ1-42 oligomers on CA1-LTP in murine hippocampal slices. Co-application of MRZ-99030 also prevented the two-fold increase in resting Ca2+ levels in pyramidal neuron dendrites and spines triggered by Aβ1-42 oligomers. In anaesthetized rats, pre-administration of MRZ-99030 (50 mg/kg s.c.) protected against deficits in hippocampal LTP following i.c.v. injection of oligomeric Aβ1-42. Furthermore, similar treatment significantly ameliorated cognitive deficits in an object recognition task and under an alternating lever cyclic ratio schedule after the i.c.v. application of Aβ1-42 and 7PA2 conditioned medium, respectively. Altogether, these results demonstrate the potential therapeutic benefit of MRZ-99030 in AD.