998 resultados para Pre-synaptic Neurotoxin
Resumo:
Undergraduate Medical Imaging (MI)students at QUT attend their first clinical placement towards the end of semester two. Students undertake two (pre)clinical skills development units – one theory and one practical. Students gain good contextual and theoretical knowledge during these units via a blended learning model with multiple learning methods employed. Students attend theory lectures, practical sessions, tutorial sessions in both a simulated and virtual environment and also attend pre-clinical scenario based tutorial sessions. The aim of this project is to evaluate the use of blended learning in the context of 1st year Medical Imaging Radiographic Technique and its effectiveness in preparing students for their first clinical experience. It is hoped that the multiple teaching methods employed within the pre-clinical training unit at QUT builds students clinical skills prior to the real situation. A quantitative approach will be taken, evaluating via pre and post clinical placement surveys. This data will be correlated with data gained in the previous year on the effectiveness of this training approach prior to clinical placement. In 2014 59 students were surveyed prior to their clinical placement demonstrated positive benefits of using a variety of learning tools to enhance their learning. 98.31%(n=58)of students agreed or strongly agreed that the theory lectures were a useful tool to enhance their learning. This was followed closely by 97% (n=57) of the students realising the value of performing role-play simulation prior to clinical placement. Tutorial engagement was considered useful for 93.22% (n=55) whilst 88.14% (n=52) reasoned that the x-raying of phantoms in the simulated radiographic laboratory was beneficial. Self-directed learning yielded 86.44% (n=51). The virtual reality simulation software was valuable for 72.41% (n=42) of the students. Of the 4 students that disagreed or strongly disagreed with the usefulness of any tool they strongly agreed to the usefulness of a minimum of one other learning tool. The impact of the blended learning model to meet diverse student needs continues to be positive with students engaging in most offerings. Students largely prefer pre -clinical scenario based practical and tutorial sessions where 'real-world’ situations are discussed.
Resumo:
The Mueller-Stokes formalism that governs conventional polarization optics is formulated for plane waves, and thus the only qualification one could require of a 4 x 4 real matrix M in order that it qualify to be the Mueller matrix of some physical system would be that M map Omega((pol)), the positive solid light cone of Stokes vectors, into itself. In view of growing current interest in the characterization of partially coherent partially polarized electromagnetic beams, there is a need to extend this formalism to such beams wherein the polarization and spatial dependence are generically inseparably intertwined. This inseparability brings in additional constraints that a pre-Mueller matrix M mapping Omega((pol)) into itself needs to meet in order to be an acceptable physical Mueller matrix. These additional constraints are motivated and fully characterized. (C) 2010 Optical Society of America
Resumo:
This clinical study focused on effects of childhood specific language impairment (SLI) on daily functioning in late life. SLI is a neurobiological disorder with genetic predisposition and manifests as poor language production or comprehension or both in a child with age-level non-verbal intelligence and no other known cause for deficient language development. The prevalence rate of around 7% puts it among the most prevalent developmental disorders in childhood. Negative long-term effects, such as problems in learning and behavior, are frequent. In follow-up studies the focus has seldom been on self-perception of daily functioning and participation, which are considered important in the International Classification of Functioning, Disability, and Health (ICF). To investigate the self-perceived aspects of everyday functioning in individuals with childhood receptive SLI compared with age- and gender-matched control populations, the 15D, 16D, and 17D health-related quality of life (HRQoL) questionnaires were applied. These generic questionnaires include 15, 16, and 17 dimensions, respectively, and give both a single index score and a profile with values on each dimension. Information on different life domains (rehabilitation, education, employment etc.) from each age-group was collected with separate questionnaires. The study groups comprised adults, adolescents (12-16 years), and pre-adolescents (8-11 years) who had received a diagnosis of receptive SLI and had been examined, usually before school age, at the Department of Phoniatrics of Helsinki University Central Hospital, where children with language deficits caused by various etiologies are examined and treated by a multidisciplinary team. The adult respondents included 33 subjects with a mean age of 34 years. Measured with 15D, the subjects perceived their HRQoL to be nearly as good as that of their controls, but on the dimensions of speech, usual activities, mental functioning, and distress they were significantly worse off. They significantly more often lived with their parents (19%) or were pensioned (26%) than the adult Finnish population on average. Adults with self-perceived problems in finding words and in remembering instructions, manifestations of persistent language impairment, showed inferior every day functioning to the rest of the study group. Of the adolescents and pre-adolescents, 48 and 51, respectively, responded. The majority in both groups had received special education or extra educational support at school. They all had attended speech therapy at some point; at the time of the study only one adolescent, but every third pre-adolescent still received speech therapy. The 16D score of the adolescent or the 17D score of the pre-adolescents did not differ from that of their controls. The 16D profiles differed on some dimensions; subjects were significantly worse off on the dimension of mental functioning, but better off on the dimension of vitality than controls. Of the 17D dimensions, the study group was significantly worse off on speech, whereas the control group reported significantly more problems in sleeping. Of the childhood performance measures investigated, low verbal intelligence quotient (VIQ), which is often considered to reflect receptive language impairment, was in adults subjects significantly associated with some of the self-perceived problems, such as problems in usual activities and mental functioning. The 15D, 16D, and 17D questionnaires served well in measuring self-perceived HRQoL. Such standardized measures with population values are especially important in confirming with the ICF guidelines. In the future these questionnaires could perhaps be used on a more individual level in follow-up of children in clinics, and even in special schools and classes, to detect those children at greatest risk of negative long-term effects and perhaps diminished well-being regarding daily functioning and participation.
Resumo:
Women with a history of pre-eclampsia have an increased risk of cardiovascular disease in later life. The mechanisms which mediate this heightened risk are poorly understood; it was long believed that pre-eclampsia was a separate disease without any connection to other pathologies. The present study was undertaken to investigate the cardiovascular risk milieu, vascular dilatory function and cardiovascular risk factors, in women with pre-eclampsia, 5 6 years after index pregnancy. The aim was to understand better the cardiovascular risks associated with pre-eclampsia and add tools to the evaluation of cardiovascular risk in women. --- The study involved 30 women with previous severe pre-eclampsia and 21 controls. The 2-day study protocol included venous occlusion plethysmography and pulse wave analysis for assessment of vascular dilatory function and central pulse wave reflection, respectively, office and ambulatory blood pressure measurements, assessment of insulin sensitivity, using a minimal model technique, and tests regarding renal function, lipid metabolism, sympathetic activity and inflammation. Vasodilatory function was impaired in women with a history of pre-eclampsia; this was seen in both endothelium-dependent and endothelium-independent vasodilatation. Proteinuria during pre-eclampsia did not predict changes in vasodilatation, and renal function was similar in the two groups. Insulin sensitivity was related to vasodilatation and features of metabolic syndrome, but only in the patient group, despite similar insulin sensitivity in the control group. Arterial pressure was higher in the patient group than in the controls and correlated with endothelin-1 levels in the patient group, whilst the overall difference between the groups was diminished in 24 hour arterial pressure measurements. Additionally, women with previous pre-eclampsia were characterized by increased sympathetic activity. Impaired vasodilatory function at the vascular smooth muscle level seems to characterize clinically healthy women with a history of pre-eclampsia. These vascular changes and the features of metabolic syndrome may be related to the increased risk of cardiovascular disease. Furthermore, increased blood pressure in combination with enhanced sympathetic activity may be additive as regards this risk. These women should be informed about their potential cardiovascular risk profile and the possibilities to minimize it via their own actions. Medical cardiovascular risk assessment in women should include obstetric history.
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Since the turn of the century there has been an increasing focus on inclusive education in Australian schools, and growing interest in understanding how the values of pre-service teachers impact on their willingness to implement inclusive principles in their future classrooms. The current qualitative study explored the values and views toward diversity and inclusion of pre-service teachers at one university in Queensland, Australia. Results showed that first and fourth year pre-service teachers held similar ideas about the values that teachers should have, and showed congruence between their own personal values and teacher values. Fourth year students who had undertaken an inclusive education minor placed greater emphasis on the importance of inclusion, and felt more confident about supporting this diversity in their future classrooms, than those fourth years who had not undertaken this minor. The findings from this study will inform future planning in preparing teachers for inclusive work in schools.
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Pre-school children grow and develop rapidly with age and their changing capabilities are reflected in the ways in which they are injured. Using coded and textual descriptions of transport-related injuries in children under five years of age from the Queensland Injury Surveillance Unit (QISU) this paper profiles the modes of such injuries by single year of age. The QISU collects information on all injury presentations to emergency department in hospitals throughout Queensland using both coded information and textual description. Almost all transport-related injuries in children under one year are due to motor vehicle crashes but these become proportionately less common thereafter, while injuries while cycling become proportionately more common with age. Slow-speed vehicle runovers peak at age one year but occur at all ages in the range. Bicycle-related fatalities are rare in this age group. If bicycle-related injuries are excluded, the profiles of fatal and non-fatal injuries are broadly similar. Comparison with a Queensland hospital series suggests that these results are broadly representative.
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While teaching is largely a White, middle-class profession, some teachers, including White teachers, come from low socio-economic backgrounds. This paper examines how one working-class pe-service teacher in Australia experiences studying in a predominantly middle-class teacher education program. Drawing on Bourdieu, this paper seeks to explore what we can learn from the pre-service teaching reflections of one woman who is a member of this smaller group of teachers and who brings to her teaching the habitus and life history that aligns with many of her students and the low socio-economic communities in which she teaches.
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The widespread deployment of commercial-scale cellulosic ethanol currently hinges on developing and evaluating scalable processes whilst broadening feedstock options. This study investigates whole Eucalyptus grandis trees as a potential feedstock and demonstrates dilute acid pre-treatment (with steam explosion) followed by pre-saccharification simultaneous saccharification fermentation process (PSSF) as a suitable, scalable strategy for the production of bioethanol. Biomass was pre-treated in dilute H2SO4 at laboratory scale (0.1 kg) and pilot scale (10 kg) to evaluate the effect of combined severity factor (CSF) on pre-treatment effectiveness. Subsequently, pilot-scale pre-treated residues (15 wt.%) were converted to ethanol in a PSSF process at 2 L and 300 L scales. Good polynomial correlations (n = 2) of CSF with hemicellulose removal and glucan digestibility with a minimum R2 of 0.91 were recorded. The laboratory-scale 72 h glucan digestibility and glucose yield was 68.0% and 51.3%, respectively, from biomass pre-treated at 190 °C /15 min/ 4.8 wt.% H2SO4. Pilot-scale pre-treatment (180 °C/ 15 min/2.4 wt.% H2SO4 followed by steam explosion) delivered higher glucan digestibility (71.8%) and glucose yield (63.6%). However, the ethanol yields using PSSF were calculated at 82.5 and 113 kg/ton of dry biomass for the pilot and the laboratory scales, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
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This study discusses the legitimacy basis of political power and its changes in historical African societies. It starts from Luc de Heusch s tenet that political power required a legitimacy basis of a spiritual kind, often formulated as sacred kingship. In ancient and pre-literate societies such kings were held to be responsible for the fertility of man, land and cattle. The king was a paradoxical figure, symbolising society, but standing above it, while simultaneously being its victim by being ritually killed at old age. This was also how Owambo sacred kings were conceived. De Heusch suggested that African kings derived their power over fertility from having been made sacred monsters in the rituals of installation. With the example of Owambo kingship, this study argues that the transgressive and monstrous aspect is only one of several dimension of a king s sacredness and brings out the nurturing and symbolically female aspect, identified but not analysed further by de Heusch. In the Owambo kingly installation a king-elect was made sacred, and part of it was that a link was ritually created to the early owners of the land. Their consent made it possible for the king to promote fertility and to appropriate power emblems needed for ruling. In the kingdom of Ondonga the early owners of the land were the spirits of early Bushman inhabitants and those of an early kingly clan, both neglected in public memory. The sacred dimension of kingship was further augmented when kings manipulated and appropriated rain rituals and initiation rituals, both of which were related to fertility. The study argues that even though there were aspects of the sacred monster in Owambo kingship, its manifestation was, in part, a distortion of the reciprocal aspect of kingship that was expressed in the homage paid to various ancestor spirits. A change in succession practices from ritual regicide to political assassination took place concomitant with the introduction of firearms, and this broke the sacrificial aspect of sacred kingship paving the way for a more predatory form of kingship while the sacred status of the king was retained.
Resumo:
The biosynthesis of β-N-oxalyl-l-α,β-diaminopropionic acid (ODAP), HOOC· CO·NH·CH2·CH(NH2·COOH is of interest, since this neurotoxin has been isolated from the seeds of Lathyrus sativus, the consumption of which causes the disease neurolathyrism in humans. The concentration of this non-protein amino acid in the seeds increases on germination. When the seeds are germinated in the presence of [14C2]- oxalic acid, the isolated ODAP is labelled exclusively in the oxalyl moiety. An oxalyl- CoA synthetase requiring the obligatory presence of ATP, CoA and Mg2+ can be demonstrated in crude extracts of the seedlings. When l-α,β-diaminopropionic acid is incubated with the enzyme in the presence of the components for oxalyl activation, net formation of ODAP can be shown. The enzymic reaction is specific to the β-amino group of l-α,β-diaminopropionic acidm and the higher homologues like α,γ-diaminobutyric acid, ornithine and lysine are inactive in this system. ODAP is not formed with α,β-diaminopropionic acid when the enzyme extract is prepared from Pisum sativum although oxalyl-CoA formation can be demonstrated.
Resumo:
Abstract—β-N-Oxalyl-l-α,β-diaminopropionic acid (ODAP), the toxin isolated from the seeds of Luthyrus sativus produces head retraction, tremors and convulsions when injected into a variety of experimental animals. In 12-day-old rats, it has been found that the convulsive behaviour is accompanied by profound biochemical changes in the brain. The brain homogenates prepared from ODAP injected animals show a higher rate of respiration. There is a decrease in the brain glucose, glycogen, ATP, phosphocreatine and acetylcholine levels of the convulsing animals. The inorganic phosphate, lactic acid and acetylcholineesterase levels increase. These results establish that ODAP is a typical convulsant.
Resumo:
A neurotoxic compound has been isolated from the seeds of Lathyrus sativus in 0.5% yield and characterized as β-N-oxalyl-L-α,β-diaminopropionic acid. The compound is highly acidic in character and forms oxalic acid and diaminopropionic acid on acid hydrolysis. The compound has a specific rotation of -36.9° and has apparent pK values in the order of 1.95, 2.95, and 9.25, corresponding to the two carboxyl and one amino functions, respectively. The compound has been synthesized by reacting an aqueous methanolic solution of the copper complex of L-α,β-diaminopropionic acid prepared at pH 4.5-5.0 with dimethyl oxalate under controlled pH conditions and isolating the compound by chromatography on a Dowex 50-H+ column after precipitating the copper. The compound induced severe neurological symptoms in day-old chicks at the level of 20 mg/chick, but not in rats or mice. It also inhibited the growth of several microorganisms and of the insect larva Corcyra cephalonica Staint. L-Homoarginine had no neural action in chicks. It is suggested that the neurotoxic compound is species specific in its action and may be related to "neurolathyrism" associated with the human consumption of L. sativus seeds.
Resumo:
The biosynthesis of β-N-oxalyl-l-α,β-diaminopropionic acid (ODAP) the Lathyrus sativus neurotoxin has been found to follow the scheme depicted below: {A figure is presented}. The first reaction is catalysed by oxalyl-CoA synthetase which has properties similar to that of the enzyme in peas. The second reaction is catalysed by another enzyme which is specific to L. sativus and is designated as oxalyl-CoA-α,β-diaminopropionic acid oxalyl transferase. The enzymes have been purified by about 60-fold and their properties studied. A partial resolution of the two enzyme activities has been achieved using CM-sephadex columns.
Resumo:
This poster describes a pilot case study, which aim is to study how future chemistry teachers use knowledge dimensions and high-order cognitive skills (HOCS) in their pre-laboratory concept maps to support chemistry laboratory work. The research data consisted of 168 pre-laboratory concept maps that 29 students constructed as a part of their chemistry laboratory studies. Concept maps were analyzed by using a theory based content analysis through Anderson & Krathwohls' learning taxonomy (2001). This study implicates that novice concept mapper students use all knowledge dimensions and applying, analyzing and evaluating HOCS to support the pre-laboratory work.