18 resultados para Head--Wounds and injuries.

em Aston University Research Archive


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Clogging is the main operational problem associated with horizontal subsurface flow constructed wetlands (HSSF CWs). The measurement of saturated hydraulic conductivity has proven to be a suitable technique to assess clogging within HSSF CWs. The vertical and horizontal distribution of hydraulic conductivity was assessed in two full-scale HSSF CWs by using two different in situ permeameter methods (falling head (FH) and constant head (CH) methods). Horizontal hydraulic conductivity profiles showed that both methods are correlated by a power function (FH= CH 0.7821, r 2=0.76) within the recorded range of hydraulic conductivities (0-70 m/day). However, the FH method provided lower values of hydraulic conductivity than the CH method (one to three times lower). Despite discrepancies between the magnitudes of reported readings, the relative distribution of clogging obtained via both methods was similar. Therefore, both methods are useful when exploring the general distribution of clogging and, specially, the assessment of clogged areas originated from preferential flow paths within full-scale HSSF CWs. Discrepancy between methods (either in magnitude and pattern) aroused from the vertical hydraulic conductivity profiles under highly clogged conditions. It is believed this can be attributed to procedural differences between the methods, such as the method of permeameter insertion (twisting versus hammering). Results from both methods suggest that clogging develops along the shortest distance between water input and output. Results also evidence that the design and maintenance of inlet distributors and outlet collectors appear to have a great influence on the pattern of clogging, and hence the asset lifetime of HSSF CWs. © Springer Science+Business Media B.V. 2011.

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Tic-like movements in rodents bear close similarities to those observed in humans both pharmacologically and morphologically. Pharmacologically, tics are modulated by serotonergic and dopaminergic systems and abnormalities of these systems have been reported in Tourette's Syndrome (TS). Therefore, serotonergic and dopaminergic modulation of tics induced by a thyrotrophin-releasing hormone (TRH) analogue were studied as possible models for TS. The TRH analogue MK771 induced a variety of tic like movements in mice; blinking fore-paw-licking and fore-paw-tremor were quantified and serotonergic and dopaminergic modulation was investigated. The selective dopamine D1 receptor antagonists SCH23390 and SCH39166 and dopamine D2 antagonists raclopride and sulpiride had no effect on MK771 induced blinking. The D1 antagonists attenuated fore-paw-tremor and -licking while the D2 antagonists were generally without effect on these behaviours. Ketanserin (5-HT2A/ alpha-1 antagonist) and ritanserin (5-HT2A/2C antagonist) were able to attenuate MK771-induced blinking and ketanserin, mianserin (5-HT2A/2C antagonist) and prazosin (alpha-1 adrenoceptor antagonist) were able to attenuate MK771-induced fore-paw-tremor and -licking. The 5-HT2C/2B antagonist SB200646A was without effect on blinking and fore-paw-licking but dose-dependently potentiated fore-paw-tremor. The 5-HT1A agonists 8-OH DPAT and buspirone attenuated blinking at the lower doses tested but were ineffective at the higher doses; the converse was found for fore-paw-licking and -tremor behaviours.The effects of these ligands appeared to be at a postsynaptic 5-HTlA site since para-chlorophenylalanine was without effect on the manipulation of these behaviours. (S)-W A Y100135 was without effect on MK771-induced behaviours, spontaneous and DOl-induced head shakes. Because kynurenine potentiates head shakes and plasma concentrations are raised in TS patients the effects of kynurenine on the 5-HT2A/2C agonist DOl mediated head shake were established. Kynurenine potentiated the DOl head shake. Attempts were made to correlate serotonergic unit activity with tic like behaviour in cats but this proved unsuccessful. However, the pharmacological understanding of 5-HTlA receptor function has been hampered because of the lack of selective antagonists for this site. For this reason the effects of the novel 5-HTlA antagonists (S)-WA Y- 100135 and WAY -100635 were tested on 5-HT single-unit activity recorded from the dorsal-raphe-nucleus in the behaving cat. Both drugs antagonised the suppression of unit activity caused by 8-0H DPAT. (S)-WA Y-100135 reduced unit activity whereas WAY-100635 increased it. This suggests that WAY-100635 is acting as an antagonist at the 5-HTlA somatodendritic autoreceptor and that (S)W A Y -100135 acts as a partial agonist at this site. Aspects of tic like behaviour and serotonergic control are discussed.

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The study of tic-like movements in mice has demonstrated close parallels both in characteristics and in pharmacology with the tics which occur in TS. Head-shakes and/or other tic-like behaviours occurring spontaneously or induced by the selective 5-HT2/1C agonist DOI, alpha-melanocyte stimulating hormone, adrenocorticotrophic hormone (1-39), thyrotropin releasing hormone, or RX336-M were blocked when tested with neuroleptics such as haloperidol and/or the alpha-2 adrenoceptor agonist clonidine. The selective dopamine D1 antagonists SCH23390 and SCH39166 dose-dependently blocked spontaneous and DOI head-shakes but the selective dopamine D2 antagonists sulpiride and raclopride were ineffective. The 5-HT1A receptor agonists 8-OH-DPAT, ipsapirone, gepirone, MDL 73005EF and buspirone (i.p) dose-dependently blocked DOI head-shakes, pindolol blocked the inhibitory effect of 8-OH-DPAT on DOI head-shakes. Parachlorophenylalanine blocked the inhibitory effect of 8-OH-DPAT and buspirone, suggesting that the 5-HT1A receptor involved is located presynaptically. The alpha-2 adrenoceptor antagonists yohimbine, idazoxan, 1-PP and RX811059 prevented the inhibitory effect of 8-OH-DPAT on DOI head-shakes suggesting that this 5-HT1A - 5-HT2 receptor interaction is under the modulatory control of adrenoceptors. Because kynurenine has previously been found to potentiate head-shaking, plasma kynurenine concentrations were measured in seven TS patients and were significantly higher than controls, but neopterin and biopterin were unchanged. The relationship between tic-like movements in rodents and their implications for understanding the aetiology and treatment of TS is discussed.

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The thymic anlagen appears in Tilapia mossambica at 2 days post hatching and becomes lymphoid at 5 days. Lymphoid cells were first seen in the pronephros at 14 days and in the spleen at approximately five weeks of age. Differentiation into red and white pulp regions was seen by 10 weeks of age. Light and electron microscopic studies of adult lymphoid organ revealed increases in size and lymphoid cell numbers. Adult thymus develops a clearer corticomedullary differentiation of thymic corpuscles in the medulla and in the splenic red and white pulp became more distinct. Melanomacrophage centres were seen in spleen and pronephros. Adult fish gave primary and secondary antibody responses following challenge with sheep red bloods cells (SRBC), Escherichia coli (E. coli) and human gamma globulin (HGG). Plaque forming cell and immunocytoadherence assays revealed that head kidney and spleen were major sites for antibody production and development of antigen reactive cells. Proliferative activity in these organs was revealed using autoradiography and scintillation counting. Increased levels of pyroninophilia were also seen following antigenic challenge. Pilot studies on adults revealed that they were capable of rejecting first and second set allografts and leucocytes from spleen and head kidney proliferated in mixed leucocyte cultures. Antibody responses to SRBC, E. coli and HGG develop at about 10-12 weeks of age. Fry given either a single injection of SRBC at 10 weeks or two injections of the same antigen at 10 weeks and 12 days later, failed to respond to a further challenge with SRBC 56 days after the first injection (A time when animals would normally respond positively to this antigen). Injection of E. coli at the same times resulted in a prolonged antibody response.

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This exploratory study seeks to provide an appreciation of brand orientation in retail banking. Through in-depth interviews at head office and branch level, we explore managers' brand mind-set. We also surface managers' views about the relationship between market and brand orientation. Further, we examine managers' perceptions about the role of brand values as resources in creating a brand orientation. In a large-scale study of front-line employees, we examine the level of agreement with brand values, and describe differences in brand buy-in across employee clusters. © 2013 Copyright Westburn Publishers Ltd.

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On the morning of January 5, 1859, at the end of the liturgy in the Orthodox cathedral in Iaşi, the capital of the principality of Moldavia, Father Neofit Scriban addressed the congregation. He had given many sermons in the cathedral; however, on this par tic u lar date Father Neofit faced an unusual audience. Among the faithful who regularly worshipped at the relics of Saint Parascheva, the protector of Moldavia, were the members of the assembly who would decide the future of the principality. They had a specific mission: to elect a new prince, a key figure in their plan to unite Moldavia with the neighboring principality of Wallachia. Father Neofit, a supporter of the unionist cause and fully aware of the significance of the moment, stated: Brethren, Jesus Christ has said that "For where two or three have gathered together in My name, I am there in their midst." You, Brethren, are not two, or three, but a real gathering in the name of God. God is in your midst. You are here in the name of the Romanian nation [and] the Romanian nation is in your midst. On the flag under which you have assembled, the flag of the Romanian nation, great events, the Romanian faith, unity, are written in large letters. The church, which is founded on faith, blesses the flag of this faith⋯. You, Brethren, through the faith of the Romanian nation, by remaining faithful to this flag, will find the same strength as the church [finds] in its own saints. The faith of the Romanian nation was not, is not, and will not be anything else, but the unity of all Romanians in a single state, the only anchor of salvation, the only port in which the national boat could be saved from surrounding waves. You, Brethren, have gathered here in the church of Stephen the Great; looking at the altar that he raised to the God of your parents, I think that, through this [altar], you will be able to enter into the wishes of this hero of our nation. You, [remember that] by leaving this place, you are leaving [in order to fulfill] a great gesture that for many centuries has been lost for us; you are about to elect a successor to this great hero; therefore, as his true sons, you could not be anything other than the true expression of his wishes. Myself, [as] last year, from this altar, I said and I will continue to say that this great hero has told us that "the God of our parents will send us a Redeemer who will heal our wounds and accomplish our wishes." May your chosen leader today be the redeemer expected by the Romanian nation. May he heal its wounds and achieve its wishes. Therefore, Brethren, may your election today be that of a real Messiah of Romania. God and the world are looking at you, the church is blessing you and the whole Romanian nation is waiting for you!1 A few hours after Father Neofit's sermon, the assembly elected Alexandru Ioan Cuza to be the prince of the principality of Moldavia; a few days later, on January 24, 1859, the assembly of the neighboring principality of Wallachia decided that Cuza should also be their prince, thus confirming the unification of the two states. A new country was inscribed on the map of Southeastern Europe, titled "The United Principalities of Wallachia and Moldavia," also known as "The United Romanian Principalities".

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Magnetoencephalography (MEG) offers significant opportunities for the localization and characterization of focal and generalized epilepsies, but its potential has so far not been fully exploited, as the evidence for its effectiveness is still anecdotal. This is particularly true for pediatric epilepsy. MEG recordings on school-age children typically rely on the use of MEG systems that were designed for adults and children's smaller head-size and stature can cause significant problems. Reduced signal-to-noise ratio when recording from smaller heads, increased movement, reduced sensor coverage of anterior temporal regions and incomplete insertion into the MEG helmet can all reduce the quality of data collected from children. We summarize these challenges and suggest some practical solutions.

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Phospholipid oxidation by adventitious damage generates a wide variety of products with potentially novel biological activities that can modulate inflammatory processes associated with various diseases. To understand the biological importance of oxidised phospholipids (OxPL) and their potential role as disease biomarkers requires precise information about the abundance of these compounds in cells and tissues. There are many chemiluminescence and spectrophotometric assays available for detecting oxidised phospholipids, but they all have some limitations. Mass spectrometry coupled with liquid chromatography is a powerful and sensitive approach that can provide detailed information about the oxidative lipidome, but challenges still remain. The aim of this work is to develop improved methods for detection of OxPLs by optimisation of chromatographic separation through testing several reverse phase columns and solvent systems, and using targeted mass spectrometry approaches. Initial experiments were carried out using oxidation products generated in vitro to optimise the chromatography separation parameters and mass spectrometry parameters. We have evaluated the chromatographic separation of oxidised phosphatidylcholines (OxPCs) and oxidised phosphatidylethanolamines (OXPEs) using C8, C18 and C30 reverse phase, polystyrene – divinylbenzene based monolithic and mixed – mode hydrophilic interaction (HILIC) columns, interfaced with mass spectrometry. Our results suggest that the monolithic column was best able to separate short chain OxPCs and OxPEs from long chain oxidised and native PCs and PEs. However, variation in charge of polar head groups and extreme diversity of oxidised species make analysis of several classes of OxPLs within one analytical run impractical. We evaluated and optimised the chromatographic separation of OxPLs by serially coupling two columns: HILIC and monolith column that provided us the larger coverage of OxPL species in a single analytical run.

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Anxiety and fear are often confounded in discussions of human emotions. However, studies of rodent defensive reactions under naturalistic conditions suggest anxiety is functionally distinct from fear. Unambiguous threats, such as predators, elicit flight from rodents (if an escape-route is available), whereas ambiguous threats (e.g., the odor of a predator) elicit risk assessment behavior, which is associated with anxiety as it is preferentially modulated by anti-anxiety drugs. However, without human evidence, it would be premature to assume that rodent-based psychological models are valid for humans. We tested the human validity of the risk assessment explanation for anxiety by presenting 8 volunteers with emotive scenarios and asking them to pose facial expressions. Photographs and videos of these expressions were shown to 40 participants who matched them to the scenarios and labeled each expression. Scenarios describing ambiguous threats were preferentially matched to the facial expression posed in response to the same scenario type. This expression consisted of two plausible environmental-scanning behaviors (eye darts and head swivels) and was labeled as anxiety, not fear. The facial expression elicited by unambiguous threat scenarios was labeled as fear. The emotion labels generated were then presented to another 18 participants who matched them back to photographs of the facial expressions. This back-matching of labels to faces also linked anxiety to the environmental-scanning face rather than fear face. Results therefore suggest that anxiety produces a distinct facial expression and that it has adaptive value in situations that are ambiguously threatening, supporting a functional, risk-assessing explanation for human anxiety.

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Purpose - To consider the role of technology in knowledge management in organizations, both actual and desired. Design/methodology/approach - Facilitated, computer-supported group workshops were conducted with 78 people from ten different organizations. The objective of each workshop was to review the current state of knowledge management in that organization and develop an action plan for the future. Findings - Only three organizations had adopted a strongly technology-based "solution" to knowledge management problems, and these followed three substantially different routes. There was a clear emphasis on the use of general information technology tools to support knowledge management activities, rather than the use of tools specific to knowledge management. Research limitations/implications - Further research is needed to help organizations make best use of generally available software such as intranets and e-mail for knowledge management. Many issues, especially human, relate to the implementation of any technology. Participation was restricted to organizations that wished to produce an action plan for knowledge management. The findings may therefore represent only "average" organizations, not the very best practice. Practical implications - Each organization must resolve four tensions: Between the quantity and quality of information/knowledge, between centralized and decentralized organization, between head office and organizational knowledge, and between "push" and "pull" processes. Originality/value - Although it is the group rather than an individual that determines what counts as knowledge, hardly any previous studies of knowledge management have collected data in a group context.

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Purpose To evaluate the effect of latanoprost 0.005% on the optic nerve head (ONH) and retinal circulation of newly diagnosed and previously untreated primary open-angle glaucoma (POAG) patients. Methods Twenty-two newly diagnosed and previously untreated POAG patients (mean age±SD: 68.38±11.92 years) were included in this longitudinal open-label study. Patients were treated with latanoprost 0.005% once a day. Intraocular pressure (IOP), systemic blood pressure (BP), mean ocular perfusion pressure (MOPP), and ocular perfusion parameters ‘volume’, ‘velocity’, and ‘flow’ measured at the optic nerve head (ONH) and retina by means of Heidelberg Retina Flowmeter system were evaluated during a 6-month follow-up period. Results Treatment with latanoprost 0.005% resulted in a significant decrease in IOP (P<0.0001) and increase in MOPP (P<0.0001). After correcting for changes in MOPP, the blood velocity measured at the ONH level was significantly higher after 6 months of treatment than at baseline (P=0.0310). In addition, blood volume and flow measured at the peripapillary retina level improved after 3 and 6 months of treatment (P=0.0170; P=0.0260, and P=0.0170; P=0.0240 respectively). Conclusion Previously untreated POAG patients exhibit reduced IOP, increased MOPP and improved ocular perfusion at the ONH and retina levels when treated with Latanoprost 0.005%. These effects could be beneficial for glaucoma patients suffering from ocular vascular dysregulation.

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The 19 channel Neuromagnetometer system in the Clinical Neurophysiology Unit at Aston University is a multi-channel system, unique in the United Kingdom. A bite bar head localisation and MRI co-registration strategy which enabled accurate and reproducible localisation of MEG data into cortical space was developed. This afforded the opportunity to study magnetic fields of the human cortex generated by stimulation of peripheral nerve, by stimulation of visceral sensory receptors and by those evoked through voluntary finger movement. Initially, a study of sensory-motor evoked data was performed in a healthy control population. The techniques developed were then applied to patients who were to undergo neurosurgical intervention for the treatment of epilepsy and I or space occupying lesions. This enabled both validation of the effective accuracy of source localisation using MEG as well as to determine the clinical value of MEG in presurgical assessment of functional localisation in human cortex. The studies in this thesis have demonstrated that MEG can repeatedly and reliably locate sources contained within a single gyrus and thus potentially differentiate between disparate gyral activation. This ability is critical in the clinical application of any functional imaging technique; which is yet to be fully validated by any other 'non-invasive' functional imaging methodology. The technique was also applied to the study of visceral sensory representation in the cortex which yielded important data about the multiple cortical representation of visceral sensory function.

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Introduction: Lower back pain treatment and compensation costs >$80 billion overall in the US. 75% of back pain is due to disc degeneration in the lumbar region of the spine. Current treatment comprises of painkillers and bed rest or as a more radical solution – interbody cage fusion. In the early stages of disc degeneration the patient would benefit from addition of an injectable gel which polymerises in situ to support the degenerated nucleus pulposus. This involves a material which is an analogue of the natural tissue capable of restoring the biomechanical properties of the natural disc. The nucleus pulposus of the intervertebral disc is an example of a natural proteoglycan consisting of a protein core with negatively charged keratin and chondroitin sulphate attached. As a result of the high fixed charge density of the proteoglycan, the matrix exerts an osmotic swelling pressure drawing sufficient water into support the spinal system. Materials and Methods: NaAMPs (sodium 2- acrylamido 2-methyl propane sulphonic acid) and KSPA (potassium 3- sulphopropyl acrylate) were selected as monomers, the sulphonate group being used to mimic the natural sulphate group. These are used in dermal applications involving chronic wounds and have acceptably low cytotoxicity. Other hydrophilic carboxyl, amide and hydroxyl monomers such as 2-hydroxyethyl acrylamide, ß-carboxyethyl acrylate, acryloyl morpholine, and polyethylene glycol (meth)acrylate were used as diluents together with polyethyleneglycol di(meth)acrylate and hydrophilic multifunctional macromers as cross-linker. Redox was the chosen method of polymerisation and a range of initiators were investigated. Components were packaged in two solutions each containing a redox pair. A dual syringe method of injection into the cavity was used, the required time for polymerisation is circa 3-7 minutes. The final materials were tested using a Bohlin CVO Rheometer cycling from 0.5-25Hz at 37oC to measure the modulus. An in-house compression testing method was developed, using dialysis tubing to mimic the cavity, the gels were swelled in solutions of various osmolarity and compressed to ~ 20%. The pre-gel has also been injected into sheep spinal segments for mechanical compression testing to demonstrate the restoration of properties upon use of the gel. Results and Discussion: Two systems resulted using similar monomer compositions but different initiation and crosslinking agents. NaAMPs and KSPA were used together at a ratio of ~1:1 in both systems with 0.25-2% crosslinking agent, diacrylate or methacrylate. The two initiation systems were ascorbic acid/oxone, and N,N,N,N - tetramethylethylenediamine (TEMED)/ potassium persulphate. These systems produced gelation within 3-7 and 3-5 minutes respectively. Storage of the two component systems was shown to be stable for approximately one month after mixing, in the dark, refrigerated at 1-4oC. The gelation was carried out at 37oC. Literature values for the natural disc give elastic constants ranging from 3-8kPa. The properties of the polymer can be tailored by altering crosslink density and monomer composition and are able to match those of the natural disc. It is possible to incorporate a radio-opaque (histodenz) to enable x-ray luminescence during and after injection. At an inclusion level of 5% the gel is clearly visible and polymerisation and mechanical properties are not altered. Conclusion: A two-pac injection system which will polymerise in situ, that can incorporate a radio-opaque, has been developed. This will reinforce the damaged nucleus pulposus in degenerative disc disease restoring adequate hydration and thus biomechanical properties. Tests on sheep spine segments are currently being carried out to demonstrate that a disc containing the gel has similar properties to an intact disc in comparison to one with a damaged nucleus.

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A large number of risk factors have been associated with Alzheimer’s disease (AD). This article discusses the validity of the major risk factors that have been identified including age, genetics, exposure to aluminium, head injury, malnutrition and diet, mitochondrial dysfunction, vascular disease, immune system dysfunction, and infection. Rare forms of early-onset familial AD (FAD) are strongly linked to the presence of specific gene mutations, viz. mutations in amyloid precursor protein (APP) and presenilin (PSEN1/2) genes. By contrast, late-onset sporadic AD (SAD) is a multifactorial disorder in which age-related changes, genetic risk factors, such as allelic variation in apolipoprotein E (Apo E) gene, vascular disease, head injury and risk factors associated with diet, the immune system, mitochondrial function, and infection may all be involved. Life-style changes that may reduce the effect of these risk factors and therefore, the risk of AD are discussed.

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Large-scale evacuations are a recurring theme on news channels, whether in response to major natural or manmade disasters. The role of warning dissemination is a key part in the success of such large-scale evacuations and its inadequacy in certain cases has been a 'primary contribution to deaths and injuries' (Hayden et al.; 2007). Along with technology-driven 'official warning channels' (e.g. sirens, mass media), the role of unofficial channel (e.g. neighbours, personal contacts, volunteer wardens) has proven to be significant in warning the public of the need to evacuate. Although post-evacuation studies identify the behaviours of evacuees as disseminators of the warning message, there has not been a detailed study that quantifies the effects of such behaviour on the warning message dissemination. This paper develops an Agent-Based Simulation (ABS) model of multiple agents (evacuee households) in a hypothetical community to investigate the impact of behaviour as an unofficial channel on the overall warning dissemination. Parameters studied include the percentage of people who warn their neighbours, the efficiency of different official warning channels, and delay time to warn neighbours. Even with a low proportion of people willing to warn their neighbour, the results showed considerable impact on the overall warning dissemination. © 2012 Elsevier B.V. All rights reserved.