885 resultados para Observer attack
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Background: Rupture of vulnerable atheromatous plaque in the carotid and coronary arteries often leads to stroke and heart attack respectively. The role of calcium deposition and its contribution to plaque stability is controversial. This study uses both an idealized and a patient-specific model to evaluate the effect of a calcium deposit on the stress distribution within an atheromatous plaque. Methods: Using a finite-element method, structural analysis was performed on an idealized plaque model and the location of a calcium deposit within it was varied. In addition to the idealized model, in vivo high-resolution MR imaging was performed on 3 patients with carotid atheroma and stress distributions were generated. The individual plaques were chosen as they had calcium at varying locations with respect to the lumen and the fibrous cap. Results: The predicted maximum stress was increased by 47.5% when the calcium deposit was located in the thin fibrous cap in the model when compared with that in a model without a deposit. The result of adding a calcium deposit either to the lipid core or remote from the lumen resulted in almost no increase in maximal stress. Conclusion: Calcification at the thin fibrous cap may result in high stress concentrations, ultimately increasing the risk of plaque rupture. Assessing the location of calcification may, in the future, aid in the risk stratification of patients with carotid stenosis.
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Objective: To describe the clinical signs, gross pathology, serology, bacteriology, histopathology, electron microscopy and immunohistochemistry findings associated with toxoplasmosis in four Indo-Pacific humpbacked dolphins (Sousa chinensis) that stranded in Queensland in 2000 and 2001. Design: Clinical assessment, gross necropsy, and laboratory examinations. Procedure: Necropsies were performed on four S chinensis to determine cause of death. Laboratory tests including serology, bacteriology, histopathology and transmission electron microscopy were done on the four dolphins. lmmunohistochemistry was done on the brain, heart, liver, lung, spleen and adrenal gland from various dolphins to detect Toxoplasma gondii antigens. Results: Necropsies showed all of four S chinensis that stranded in Queensland in 2000 and 2001 had evidence of predatory shark attack and three were extremely emaciated. Histopathological examinations showed all four dolphins had toxoplasmosis with tissue cysts resembling T gondii in the brain. Tachyzoite stages of T gondii were detected in the lungs, heart, liver, spleen and adrenal gland, variously of all four dolphins. Electron microscopy studies and immunohistochemistry confirmed the tissues cysts were those of Tgondii. All four dolphins also had intercurrent disease including pneumonia, three had peritonitis and one had pancreatitis. Conclusion: Four S chinensis necropsied in Queensland in 2000 and 2001 were found to be infected with toxoplasmosis. It is uncertain how these dolphins became infected and further studies are needed to determine how S chinensis acquire toxoplasmosis. All four dolphins stranded after periods of heavy rainfall, and coastal freshwater runoff may be a risk factor for T gondii infection in S chinensis. This disease should be of concern to wildlife managers since S chinensis is a rare species and its numbers appear to be declining.
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The fungus causing anthracnose disease in mango, Colletotrichum gloeosporioides, (C g.), infects immature fruit early in the season, then enters a long latent phase. After harvest, when fruit start to ripen, the latency breaks and the fungus ramifies through the peel and pulp tissues causing black disease lesions. The breaking of pathogen latency in ripening mango fruit has been correlated with decreasing concentrations of the endogenous antifungal resorcinol compounds (Droby et al., 1986). The level of these antifungal resorcinols vary among mango cultivars (Droby et a1 , 1986). Controlling diseases by managing natural resistance of fruit to fungal attack could minimize the use of pesticides, which have become of major public concern on health and environmental grounds. The plant resistance activator benzo(l,2,3)thiadiazole-7-carbothioic acid S-methyl ester (trade name Bion®) has been widely reported as an effective inducer of systemic resistance. For example, Bion® was reported to induce pathogenesis-related proteins (PR proteins) and stimulate plant defence in peas (Dann and Deverall, 2000) and roses (Suo and Leung, 2001). However, until now, there is no information about the role of Bion® in activation of mango (cv. Kensington Pride) fruit resistance to anthracnose disease. The aim of this research is to determine the effect of resistance activators on defence responses of mango fruit to anthracnose disease.
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Matti Laurila (1895 1983) This is a biographical research of a Jaeger officer, a Civil Guard Chief, a Field Commander Matti Laurila. A broader practice of qualitative methods was utilized in the research. The main aim is a permanent reconstruction and reinterpretation of past events through the experiences of the study object. The life and times of Laurila are intertwined with the crucial events that led to the Finnish Declaration of Independence. Afterwards he helped to ensure that the young republic also stayed independent. As a Jaeger in the winter of 1917 Laurila witnessed an incident he would never forget. After disobeying a direct order, Sven Saarikoski from Lapua was shot dead by his commanding officer, K. A. Ståhlberg, on the ice of the river Aa. Laurila faced the horrors of war at closer quarters, for he lost his father and his brother in the battle of Länkipohja on 16th March 1918. This battle was a major turning point for Laurila and profoundly influenced the rest of his life. The relationship between Laurila and his superiors was problematic almost throughout his military career, haunted as he was by the memory of Sven Saarikoski's execution and the losses in Länkipohja The position of Laurila as an authority in South Ostrobothnia was a key factor in preventing the extreme right from rallying enough Civil Guard troops to escalate the embryonic Mäntsälä rebellion of 1932. After the rebellion Laurila routinely opposed anything he saw as a threat to the independence of the Civil Guard. He would flatly refuse to even consider the integration of the Civil Guard into the national defence force. His uncompromising stand in this matter annoyed some among the higher ranking officers. After the Winter War Laurila got himself into a dispute with Jaeger Colonel H. E. Hannuksela that would have long-lasting consequences. The conflicts between them became widely known in the attack phase of the Continuation War in 1941 at the latest. Laurila had to give up his military career at the end of 1944. In the years that followed he did what he could to ensure that the South Ostrobothnia Civil Guard patrimony remained in the province. Laurila's position as a respected authority in South Ostrobothnia remained unchanged until his death.
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The reactions of terminal borylene complexes of the type [CpFe(CO)(2)(BNR2)](+) (R = `Pr, Cy) with heteroallenes have been investigated by quantum-chemical methods, in an attempt to explain the experimentally observed product distributions. Reaction with dicyclohexylcarbodiimide (CyNCNCy) gives a bis-insertion product, in which 1 equiv of carbodiimide is assimilated into each of the Fe=B and B=N double bonds to form a spirocyclic boronium system. In contrast, isocyanates (R'NCO, R' = Ph, 2,6-wXy1, CY; XYl = C6H3Me2) react to give isonitrile complexes of the type [CpFe(CO)(2)(CNR')]+, via a net oxygen abstraction (or formal metathesis) process. Both carbodiimide and socyanate substrates are shown to prefer initial attack at the Fe=B bond rather than the B=N bond of the borylene complex. Further mechanistic studies reveal that the carbodiimide reaction ultimately leads to the bis-insertion compounds [CpFe(CO)(2)C(NCy)(2)B(NCY)(2)CNR2](+), rather than to the isonitrile system [CpFe(CO)(2)(CNCy)](+), on the basis of both thermodynamic (product stability) and kinetic considerations (barrier heights). The mechanism of the initial carbodiimide insertion process is unusual in that it involves coordination of the substrate at the (borylene) ligand followed by migration of the metal fragment, rather than a more conventional process: i.e., coordination of the unsaturated substrate at the metal followed by ligand migration. In the case of isocyanate substrates, metathesis products are competitive with those from the insertion pathway. Direct, single-step metathesis reactivity to give products containing a coordinated isonitrile ligand (i.e. [CpFe(CO)(2)(CNR')](+)) is facile if initial coordination of the isocyanate at boron occurs via the oxygen donor (which is kinetically favored); insertion chemistry is feasible when the isocyanate attacks initially via the nitrogen atom. However, even in the latter case, further reaction of the monoinsertion product so formed with excess isocyanate offers a number of facile (low energetic barrier) routes which also generate ['CpFe(CO)(2)(CNR')](+), rather than the bis-insertion product [CpFe(CO)(2)C(NR')(O)B(NR')(O)CNR2](+) (i.e., the direct analogue of the observed products in the carbodiimide reaction).
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Creontiades spp. (Hemiptera: Miridae) are sucking pests that attack buds, flowers and young pods in mungbeans, Vigna radiata (L.), causing these structures subsequently to abort. If left uncontrolled, mirids can cause 25-50% yield loss. Traditional industry practice has involved prophylactic applications of dimethoate to control mirids at budding and again a week later. The present trial was initiated to highlight the dangers of such a practice, in particular the risk of a subsequent Helicoverpa spp. lepidopteran pest outbreak. A single application of dimethoate halved the population of important natural enemies of Helicoverpa spp., and caused an above-threshold outbreak of Helicoverpa spp. within 11 days. This shows that even a moderate (e.g. 50%) reduction in natural enemies may be sufficient to increase Helicoverpa spp. populations in mungbeans. As a result, prophylactic sprays should not be used for the control of mirids in mungbeans, and dimethoate should be applied only when mirids are above the economic threshold. Indoxacarb was also tested to establish its effect on Helicoverpa spp., mirids and natural enemies. Indoxacarb showed potential for Helicoverpa spp. control and suppression of mirids and had little impact on natural enemies.
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In the research on the Continuation War, interest in the events themselves had exceeded the interest in military planning. Careful consideration has not been given to the planning process and the options that were available. This study shows how the planning of these operations was carried out and identifies the persons responsible. Contrary to earlier research this study shows that persons other than Field-Marshal Carl Gustaf Mannerheim and Quartermaster-General Aksel Airo took part in the planning. Furthermore, the plan was to carry out the operations further east than was ultimately done. The operation plans were coordinated by the Operations Department of Headquarters, which had the opportunity to influence on both Mannerheim and Airo. Part of the actual planning was made outside Headquarters, but final decisions were taken at Headquarters. It is worth observing that many times Mannerheim asked President Risto Ryti for his opinion concerning these operations. The Germans tried to influence the Finnish plans, but the Finns took their decisions independently, although they took German requests into account. It is well-known that the attack by the Finnish forces was stopped at the end of the year 1941. It is less well-known that the Finns planned new attacks until the autumn of 1942. At that point the Finns were convinced that the Germans would lose the war. The Finns were thus prepared to keep advancing should the Germans progress in the direction of Leningrad. This study shows that the Finnish military leaders worked for Finland s own plans and their cooperation with the Germans was directed to achieving this goal. In other words, Finland tried expand eastward with the help of the Germans. This purpose was particularly evident in the planning of the operations in the Hanko district and the Karelian Isthmus in the summer and autumn of 1941, in the Sorokka district in the spring of 1942 and around Lake Ladoga in the summer and autumn of 1942. The Finns reduced their activities when Germans took over responsibility for the operations. However, at the same time the Finns tried to support Germans in passive ways. The Finns justified the decrease in their activities with lack of Finnish forces and numerous defeats. Earlier research has shown that Finland was an active operator in the Continuation War and tried to take back the areas lost in the Winter War. In this study that view becomes more precise and clear especially with regard to Field-Marshal Mannerheim and other high military leaders. There is clear indication that the Finns would have attacked much further east had a German success made such an attack possible.
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In south-eastern Queensland, Australia, sorghum planted in early spring usually escapes sorghum midge, Stenodiplosis sorghicola, attack. Experiments were conducted to better understand the role of winter diapause in the population dynamics of this pest. Emergence patterns of adult midge from diapausing larvae on the soil surface and at various depths were investigated during spring to autumn of 1987/88–1989/90. From 1987/88 to 1989/90, 89%, 65% and 98% of adult emergence, respectively, occurred during November and December. Adult emergence from larvae diapausing on the soil surface was severely reduced due to high mortality attributed to surface soil temperatures in excess of 40°C, with much of this mortality occurring between mid-September and mid-October. Emergence of adults from the soil surface was considerably delayed in the 1988/89 season compared with larvae buried at 5 or 10 cm which had similar emergence patterns for all three seasons. In 1989/90, when a 1-cm-deep treatment was included, there was a 392% increase in adult emergence from this treatment compared with deeper treatments. Some diapausing larvae on the surface did not emerge at the end of summer in only 1 year (1989/90), when 28.0% of the larvae on the surface remained in diapause, whereas only 0.8% of the buried larvae remained in diapause. We conclude that the pattern of emergence explains why spring plantings of sorghum in south-eastern Queensland usually escape sorghum midge attack.
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Introduction: Apathy, agitated behaviours, loneliness and depression are common consequences of dementia. This trial aims to evaluate the effect of a robotic animal on behavioural and psychological symptoms of dementia in people with dementia living in long-term aged care. Methods and analysis: A cluster-randomised controlled trial with three treatment groups: PARO (robotic animal), Plush-Toy (non-robotic PARO) or Usual Care (Control). The nursing home sites are Australian Government approved and accredited facilities of 60 or more beds. The sites are located in South-East Queensland, Australia. A sample of 380 adults with a diagnosis of dementia, aged 60 years or older living in one of the participating facilities will be recruited. The intervention consists of three individual 15 min non-facilitated sessions with PARO or Plush- Toy per week, for a period of 10 weeks. The primary outcomes of interest are improvement in agitation, mood states and engagement. Secondary outcomes include sleep duration, step count, change in psychotropic medication use, change in treatment costs, and staff and family perceptions of PARO or Plush-Toy. Video data will be analysed using Noldus XT Pocket Observer; descriptive statistics will be used for participants’ demographics and outcome measures; cluster and individual level analyses to test all hypotheses and Generalised Linear Models for cluster level and Generalised Estimation Equations and/or Multi-level Modeling for individual level data. Ethics and dissemination: The study participants or their proxy will provide written informed consent. The Griffith University Human Research Ethics Committee has approved the study (NRS/03/14/HREC). The results of the study will provide evidence of the efficacy of a robotic animal as a psychosocial treatment for the behavioural and psychological symptoms of dementia. Findings will be presented at local and international conference meetings and published in peer-reviewed journals.
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Photo-oxidation of α,β-unsaturated thiones yields the corresponding ketones as the only product. Studies carried out on three systems, namely thioketones, α,β-unsaturated thiones and thioketenes, have revealed that there exists a similarity in their mechanism of oxidation. It has been suggested that the thiocarbonyl chromophore is the site of attack by singlet oxygen in α,β-unsaturated thiones and that the adjacent C-C double bond is inert under these conditions. Absence of sulphine during the oxidation of α,β-unsaturated thiones is attributed to the electronic factors operating on the zwitterionic/diradical intermediate. While α,β-unsaturated ketones are poorly reactive, α,β-unsaturated thiones are highly reactive toward singlet oxygen.
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Background Segmental biomechanics of the scoliotic spine are important since the overall spinal deformity is comprised of the cumulative coronal and axial rotations of individual joints. This study investigates the coronal plane segmental biomechanics for adolescent idiopathic scoliosis patients in response to physiologically relevant axial compression. Methods Individual spinal joint compliance in the coronal plane was measured for a series of 15 idiopathic scoliosis patients using axially loaded magnetic resonance imaging. Each patient was first imaged in the supine position with no axial load, and then again following application of an axial compressive load. Coronal plane disc wedge angles in the unloaded and loaded configurations were measured. Joint moments exerted by the axial compressive load were used to derive estimates of individual joint compliance. Findings The mean standing major Cobb angle for this patient series was 46°. Mean intra-observer measurement error for endplate inclination was 1.6°. Following loading, initially highly wedged discs demonstrated a smaller change in wedge angle, than less wedged discs for certain spinal levels (+ 2,+1,− 2 relative to the apex, (p < 0.05)). Highly wedged discs were observed near the apex of the curve, which corresponded to lower joint compliance in the apical region. Interpretation While individual patients exhibit substantial variability in disc wedge angles and joint compliance, overall there is a pattern of increased disc wedging near the curve apex, and reduced joint compliance in this region. Approaches such as this can provide valuable biomechanical data on in vivo spinal biomechanics of the scoliotic spine, for analysis of deformity progression and surgical planning.
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A blunt-nosed hypersonic missile mounted with a forward-facing cavity is a good alternative to reduce the stagnation heating rates. The effects of a forward-racing cavity on heat transfer and aerodynamic coefficients are addressed in this paper. Tests were carried out in hypersonic shock tunnel HST2, at a hypersonic Mach number of 8 using a 41 deg apex-angle blunt cone. The aerodynamic forces on the test model with and without a forward-facing cavity at various angles of attack are measured by using an internally mountable accelerometer force balance system. Heat flux measurements have been carried out on the test model with and without a forward-facing cavity of the entire surface at zero degree angle of attack with platinum sensors. A numerical simulation was also carried out using the computational fluid dynamics code (CFX-Ansys 5.7). An important result of this study is that the smaller cavity diameter has the highest lift-to-drag ratio, whereas the medium cavity has the highest heat flux reduction. Theshock structure around the test model has also been visualized using the Schlieren flow visualization technique. The visualized shock structure and the measured aerodynamic forces on the missile-shaped body with cavity configurations agree well with the axisymmetric numerical simulations.
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Associations between injury and muscle asymmetries, as determined with magnetic resonance (MR) imaging, have been investigated in a number of sports medicine-based studies. For interventional or prospective studies into musculoskeletal injuries, it is important to determine the repeatability of the morphometric procedures used for quantifying muscle asymmetries. This study examines the intra-observer repeatability of manual segmentation for determining bilateral volumes of the individual hamstring muscles.
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Line-transect distance sampling is a widely used method for estimating animal density from aerial surveys. Analysis of line-transect distance data usually relies on a requirement that the statistical distribution of distances of animal groups from the transect line is uniform. We show that this requirement is satisfied by the survey design if all other assumptions of distance sampling hold, but it can be violated by consistent survey problems such as responsive movement of the animals towards or away from the observer. We hypothesise that problems with the uniform requirement are unlikely to be encountered for immobile taxa, but might become substantial for species of high mobility. We test evidence for non-uniformity using double-observer distance data from two aerial surveys of five species with a spectrum of mobility capabilities and tendencies. No clear evidence against uniformity was found for crabeater seals or emperor penguins on the pack-ice in East Antarctica, while minor non-uniformity consistent with responsive movement up to 30 m was found for Adelie penguins. Strong evidence of either non-uniformity or a failure of the capture-recapture validating method was found for eastern grey kangaroos and red kangaroos in Queensland.
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Humans are a social species with the internal capability to process social information from other humans. To understand others behavior and to react accordingly, it is necessary to infer their internal states, emotions and aims, which are conveyed by subtle nonverbal bodily cues such as postures, gestures, and facial expressions. This thesis investigates the brain functions underlying the processing of such social information. Studies I and II of this thesis explore the neural basis of perceiving pain from another person s facial expressions by means of functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG). In Study I, observing another s facial expression of pain activated the affective pain system (previously associated with self-experienced pain) in accordance with the intensity of the observed expression. The strength of the response in anterior insula was also linked to the observer s empathic abilities. The cortical processing of facial pain expressions advanced from the visual to temporal-lobe areas at similar latencies (around 300 500 ms) to those previously shown for emotional expressions such as fear or disgust. Study III shows that perceiving a yawning face is associated with middle and posterior STS activity, and the contagiousness of a yawn correlates negatively with amygdalar activity. Study IV explored the brain correlates of interpreting social interaction between two members of the same species, in this case human and canine. Observing interaction engaged brain activity in very similar manner for both species. Moreover, the body and object sensitive brain areas of dog experts differentiated interaction from noninteraction in both humans and dogs whereas in the control subjects, similar differentiation occurred only for humans. Finally, Study V shows the engagement of the brain area associated with biological motion when exposed to the sounds produced by a single human being walking. However, more complex pattern of activation, with the walking sounds of several persons, suggests that as the social situation becomes more complex so does the brain response. Taken together, these studies demonstrate the roles of distinct cortical and subcortical brain regions in the perception and sharing of others internal states via facial and bodily gestures, and the connection of brain responses to behavioral attributes.