943 resultados para aggressive scenario


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We report here on a series of laboratory experiments on plumes, undertaken with the object of simulating the effect of the heat release that occurs in clouds on condensation of water vapor. The experimental technique used for this purpose relies on ohmic heating generated in an electrically conducting plume fluid subjected to a suitable alternating voltage across specified axial stations in the plume flow [Bhat et al., 1989]. The present series of experiments achieves a value of the Richardson number that is toward the lower end of the range that characteristics cumulus clouds. It is found that the buoyancy enhancement due to heating disrupts the eddy structures in the flow and reduces the dilution owing to entrainment of ambient fluid that would otherwise have occurred in the central region of the plume. Heating also reduces the spread rate of the plume, but as it accelerates the flow as well, the overall specific mass flux in the plume does not show a very significant change at the heat input employed in the experiment. However, there is some indication that the entrainment rate (proportional to the streamwise derivative of the mass flux) is slightly higher immediately after heat injection and slightly lower farther downstream. The measurements support a previous proposal for a cloud scenario [Bhat and Narasimha, 1996] and demonstrate how fresh insights into certain aspects of the fluid dynamics of clouds may be derived from the experimental techniques employed here.

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The cobalt(II) tris(bipyridyl) complex ion encapsulated in zeolite-Y supercages exhibits a thermally driven interconversion between a low-spin and a high-spin state-a phenomenon not observed for this ion either in solid state or in solution. From a comparative study of the magnetism and optical spectroscopy of the encapsulated and unencapsulated complex ion, supported by molecular modeling, such spin behavior is shown to be intramolecular in origin. In the unencapsulated or free state, the [Co(bipy)(3)](2+) ion exhibits a marked trigonal prismatic distortion, but on encapsulation, the topology of the supercage forces it to adopt a near-octahedral geometry. An analysis using the angular overlap ligand field model with spectroscopically derived parameters shows that the geometry does indeed give rise to a low-spin ground state, and suggests a possible scenario for the spin state interconversion.

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Recent research suggests that aggressive driving may be influenced by driver perceptions of their interactions with other drivers in terms of ‘right’ or ‘wrong’ behaviour. Drivers appear to take a moral standpoint on ‘right’ or ‘wrong’ driving behaviour. However, ‘right’ or ‘wrong’ in the context of road use is not defined solely by legislation, but includes informal rules that are sometimes termed ‘driving etiquette’. Driving etiquette has implications for road safety and public safety since breaches of both formal and informal rules may result in moral judgement of others and subsequent behaviours designed to punish the ‘offender’ or ‘teach them a lesson’. This paper outlines qualitative research that was undertaken with drivers to explore their understanding of driving etiquette and how they reacted to other drivers’ observance or violation of their understanding. The aim was to develop an explanatory framework within which the relationships between driving etiquette and aggressive driving could be understood, specifically moral judgement of other drivers and punishment of their transgression of driving etiquette. Thematic analysis of focus groups (n=10) generated three main themes: (1) courtesy and reciprocity, and the notion of two-way responsibility, with examples of how expectations of courteous behaviour vary according to the traffic interaction; (2) acknowledgement and shared social experience: ‘giving the wave’; and (3) responses to breaches of the expectations/informal rules. The themes are discussed in terms of their roles in an explanatory framework of the informal rules of etiquette and how interactions between drivers can reinforce or weaken a driver’s understanding of driver etiquette and potentially lead to driving aggression.

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Non-Abelian quantum Hall states are characterized by the simultaneous appearance of charge and neutral gapless edge modes, with the structure of the latter being intricately related to the existence of bulk quasiparticle excitations obeying non-Abelian statistics. Here we propose a scenario for detecting the neutral modes by having two point contacts in series separated by a distance set by the thermal equilibration length of the charge mode. We show that by using the first point contact as a heating device, the excess charge noise measured at the second point contact carries a nontrivial signature of the presence of the neutral mode. We also obtain explicit expressions for the thermal conductance and corresponding Lorentz number for transport across a quantum point contact between two edges held at different temperatures and chemical potentials.

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Previously, we reported catch-up weight gain, growth, and improved lung function in a group of malnourished cystic fibrosis (CF) children receiving aggressive nutritional supplementation for 1 year compared with a forced expiratory volume in 1 s (FEV1)-, height-, and sex-matched comparison group receiving standard therapy. To evaluate long-term effects, the clinical progress of both groups has been studied over a 5 year period. The supplemented group (n = 10) received supplements for a median of 1.35 years to achieve nutritional rehabilitation. Compared with the nonsupplemented group (n = 14), the previously supplemented group had lower mortality (2 vs. 4, N.S.) and significantly greater weight and height z scores at 4 and 5 years. The progression of pulmonary function abnormalities as measured by FEV, and forced vital capacity (FVC) slopes was greater at 3 years in the nonsupplemented group (FEV1, p < 0.05) but no significant differences in rates of deterioration of pulmonary function were seen after 5 years in the two groups of survivors. We conclude that intensive nutritional support for 1 year has both short-and long-term effects on nutrition and growth, still evident some years after the cessation of this therapeutic modality. Supplementation for periods of longer than 1 year may produce greater gains and possibly prolong the improvement in pulmonary function observed in the earlier study. © 1992 Raven Press, Ltd., New York.

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Cooperation among unrelated individuals is an enduring evolutionary riddle and a number of possible solutions have been suggested. Most of these suggestions attempt to refine cooperative strategies, while little attention is given to the fact that novel defection strategies can also evolve in the population. Especially in the presence of punishment to the defectors and public knowledge of strategies employed by the players, a defecting strategy that avoids getting punished by selectively cooperating only with the punishers can get a selective benefit over non-conditional defectors. Furthermore, if punishment ensures cooperation from such discriminating defectors, defectors who punish other defectors can evolve as well. We show that such discriminating and punishing defectors can evolve in the population by natural selection in a Prisoner’s Dilemma game scenario, even if discrimination is a costly act. These refined defection strategies destabilize unconditional defectors. They themselves are, however, unstable in the population. Discriminating defectors give selective benefit to the punishers in the presence of non-punishers by cooperating with them and defecting with others. However, since these players also defect with other discriminators they suffer fitness loss in the pure population. Among the punishers, punishing cooperators always benefit in contrast to the punishing defectors, as the latter not only defect with other punishing defectors but also punish them and get punished. As a consequence of both these scenarios, punishing cooperators get stabilized in the population. We thus show ironically that refined defection strategies stabilize cooperation. Furthermore, cooperation stabilized by such defectors can work under a wide range of initial conditions and is robust to mistakes.

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Objectives: The aim of this study was to evaluate the effects of low-dose (10 mg) and high-dose (80 mg) atorvastatin on carotid plaque inflammation as determined by ultrasmall superparamagnetic iron oxide (USPIO)-enhanced carotid magnetic resonance imaging (MRI). The hypothesis was that treatment with 80 mg atorvastatin would demonstrate quantifiable changes in USPIO-enhanced MRI-defined inflammation within the first 3 months of therapy. Background: Preliminary studies indicate that USPIO-enhanced MRI can identify macrophage infiltration in human carotid atheroma in vivo and hence may be a surrogate marker of plaque inflammation. Methods: Forty-seven patients with carotid stenosis >40% on duplex ultrasonography and who demonstrated intraplaque accumulation of USPIO on MRI at baseline were randomly assigned in a balanced, double-blind manner to either 10 or 80 mg atorvastatin daily for 12 weeks. Baseline statin therapy was equivalent to 10 mg of atorvastatin or less. The primary end point was change from baseline in signal intensity (ΔSI) on USPIO-enhanced MRI in carotid plaque at 6 and 12 weeks. Results: Twenty patients completed 12 weeks of treatment in each group. A significant reduction from baseline in USPIO-defined inflammation was observed in the 80-mg group at both 6 weeks (ΔSI 0.13; p = 0.0003) and at 12 weeks (ΔSI 0.20; p < 0.0001). No difference was observed with the low-dose regimen. The 80-mg atorvastatin dose significantly reduced total cholesterol by 15% (p = 0.0003) and low-density lipoprotein cholesterol by 29% (p = 0.0001) at 12 weeks. Conclusions: Aggressive lipid-lowering therapy over a 3-month period is associated with significant reduction in USPIO-defined inflammation. USPIO-enhanced MRI methodology may be a useful imaging biomarker for the screening and assessment of therapeutic response to "anti-inflammatory" interventions in patients with atherosclerotic lesions. (Effects of Atorvastatin on Macrophage Activity and Plaque Inflammation Using Magnetic Resonance Imaging [ATHEROMA]; NCT00368589).

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Inflammation is a recognized risk factor for the vulnerable atherosclerotic plaque. USPIO-enhanced MRI imaging is a promising non-i nvasive method to identify high-risk atheromatous plaque inflammation in vivo in humans, in which areas of focal signal loss on MR images have been shown to correspond to the location of activated macrophages, typically at the shoulder regions of the plaque. This is the first report in humans describing simultaneous USPIO uptake within atheroma in two different arterial territories and again emphasises that atherosclerosis is a truly systemic disease. With further work, USPIO-enhanced MR imaging may be useful in identifying inflamed vulnerable atheromatous plaques in vivo, so refining patient selection for intervention and allowing appropriate early aggressive pharmacotherapy to prevent plaque rupture.

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This paper presents a global-optimisation frame-work for the design of a manipulator for harvesting capsicum(peppers) in the field. The framework uses a simulated capsicum scenario with automatically generated robot models based on DH parameters. Each automatically generated robot model is then placed in the simulated capsicum scenario and the ability of the robot model to get to several goals (capsicum with varying orientations and positions) is rated using two criteria:the length of a collision-free path and the dexterity of the end-effector. These criteria form the basis of the objective function used to perform a global optimisation. The paper shows a preliminary analysis and results that demonstrate the potential of this method to choose suitable robot models with varying degrees of freedom.

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Driving can be a lonely activity. While there has been a lot of research and technical inventions concerning car-to-car communication and passenger entertainment, there is still little work concerning connecting drivers. Whereas tourism is very much a social activity, drive tourists have few options to communicate with fellow travellers. The proposed project is placed at the intersection of tourism and driving and aims to enhance the trip experience during driving through social interaction. This thesis explores how a mobile application that allows instant messaging between travellers sharing similar context can add to road trip experiences. To inform the design of such an application, the project adopted the principle of the user-centred design process. User needs were assessed by running an ideation workshop and a field trip. Findings of both studies have shown that tourists have different preferences and diverse attitudes towards contacting new people. Yet all participants stressed the value of social recommendations. Based on those results and a later expert review, three prototype versions of the system were created. A prototyping session with potential end users highlighted the most important features including the possibility to view user profiles, choose between text and audio input and receive up-to-date information. An implemented version of the prototype was evaluated in an exploratory study to identify usability related problems in an actual use case scenario as well as to find implementation bugs. The outcomes of this research are relevant for the design of future mobile tourist guides that leverage from benefits of social recommendations.

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My PhD-thesis Body Images! Psychoanalytical Analysis of Finnish Performance and Body Art in the 1980s and 1990s considers Finnish performance and body art performed mainly by visual artists. In Part I, I chart the historical construction of performance art and its extension since the beginning of the 21st century. There are several wievs of the historical background of performance art. I introduce three different genealogies of performance art. One is Rose-Lee Goldberg s view. She connects performance art with the European avant-garde already at the beginning of the 20th century from futurists and dadaists to Russian avant-garde and the Bauhaus. I prefer to present performance art as contemporary art, which began to take shape in connection with visual arts in the 1950s and 1960s. The focus on the body is apparent in nearly all performance art. Nevertheless, throug the concept of body art I want to empasize the artist s body as the place of art. Body art (as part of performance art) functions as thematic and interpretive concept, which allows me to focus on performances where the questions of body image, narcissism, desire, language and pleasure are incorporated in particular intensive ways. In Part II, I explore the arrival of performance art in Finnish visual arts in the 1980s. I study the new generation s relation to earlier Finnish happenings (1960s) and performative actions in 1970 s. I briefly introduce performance groups of the 1980s art scene and consider their reception in media. The main focus is on the group Jack Helen Brut, in which I see many similarities to the so- called Theatre of Images. The goal of this part II is to provide historical context for the performance analysis that follows. In Part III, I develop the concept of body image which is my main theoretical term. The concept of body image is used according to Lacanian psychoanalytical theory, especially his considerations of mirror stages. My first mapping of body image, which I call imaginary body image, is based on Lacan s famous mirror stage article (1949). According to my reading, body image is narcistic and aggressive. The important concepts here are ego, imaginary, méconnaisance and alienation. In 1953 Lacan began to develop different version on mirror stage, in which he emphasized the primacy of symbolic dimension. It is not image, but language which constructs the foundations of body image. Central concepts in this chater are Other as language, ego-ideal, demand and desire. In the last chapter I connect the third version of the mirror stage to concepts of gaze, phantasy, real, jouissance and object a. In previous chapters I had considered body image in relation to ego. Now I explore it in relation to subject. In my reading the body image is fragile phenomen, which oscillates between yearning for coherence and phantasies of fragmented images. Part IV of the thesis begins with an introduction to the central concepts and debates in performace studies over the last few decades. Important concepts are presence, performativity and theatricality. The main substance of my thesis, however, is the performance analysis, which focuses on works by three Finnish artists and one Finnish group. The first analysis concerns the performance (1992) of Kimmo Schroderus. I discuss the relationship between narcissism and body art and the changes in demands projected on body images of men in recent decades in a Euro-American context. I also explore this performance in relation to the myth of Narcissus, which I reinterpret through Narcissus s aggression against his own body. The group Homo S is the main subject of the next analysis. I discuss the relationship between feminist art and performance art, especially in the United States in the 1960s and 1970s. Homo S is different from this early performance art because of its anarchism, humor and rejection of all ideals. Homo S characterizes its performance Body Body (1983) as liberating vulgar feminism . Sociality and performance of erotic relations between women are central in Body Body. Pia Lindman s performances are the subjects of my third analysis. I study three of her performances: Olen muoto (1993), 17 and in love (1994) and Arranged views (1995). I interpret these performances as efforts to disperse the imaginary and symbolic structures of the body image. She constructs the peculiar object a and phantasy space of her own. In the last analysis I move from questions of image and gaze to a study of language, sound and jouissance. I discuss at a general level the performance of orality and helplesness (Hilflosigkeit) in body art. The central elements in Pentti Otto Koskinen s performances are the ear, listening and receptive gestures and postions. Perseveraatio (1998) can be understood representing as submission to the super-ego s power, which compels one to enjoy. I examine particularly closely the performance Maissi on hyvää ei missään nimessä maissia (1995), which I interpret as the return of a baby s body image to the liminal site of choice: language or jouissance?

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Seventy three isolates of Pythium aphanidermatum obtained from cucumber from four different regions of Oman and 16 isolates of muskmelon from the Batinah region in Oman were characterized for aggressiveness, sensitivity to metalaxyl and genetic diversity using AFLP fingerprinting. Twenty isolates of P. aphanidermatum from diverse hosts from different countries were also included in the study. Most isolates from Oman were found to be aggressive on cucumber seedlings and all were highly sensitive to metalaxyl (EC50 < 0•80 µg mL−1). Isolates from cucumber and muskmelon were as aggressive as each other on both hosts (P > 0.05), which implies a lack of host specialization in P. aphanidermatum on these two hosts in Oman. AFLP analysis of all isolates using four primer-pair combinations resolved 152 bands, of which 61 (~40%) were polymorphic. Isolates of P. aphanidermatum from Oman and other countries exhibited high genetic similarity (mean = 94.1%) and produced 59 different AFLP profiles. Analysis of molecular variance indicated that most AFLP variation among populations of P. aphanidermatum in Oman was associated with geographical regions (FST = 0.118; P < 0.0001), not hosts (FST = -0.004; P = 0.4323). These data were supported by the high rate of recovery (24%) of identical phenotypes between cucumber and muskmelon fields in the same region as compared to the low recovery (10%) across regions in Oman, which suggests more frequent movement of Pythium inoculum among muskmelon and cucumber fields in the same region compared to movement across geographically separated regions. However, recovering clones among regions and different countries may imply circulation of Pythium inoculum via common sources in Oman and also intercontinental spread of isolates.

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A study was undertaken in 2004 and 2005 to characterize pathogens associated with damping-off of greenhouse-grown cucumber seedlings in 13 districts in Oman. Identification of Pythium to the species level was based on sequences of the internal transcribed spacer (ITS) of the ribosomal DNA. Of the 98 Pythium isolates collected during the survey, Pythium aphanidermatum, P. spinosum, P. splendens and P. oligandrum accounted for 76%, 22%, 1% and 1%, respectively. Pythium aphanidermatum was isolated from all of the districts, while P. spinosum was isolated from seven districts. Pathogenicity tests showed inter- and intraspecific variation in aggressiveness between Pythium species. Pythium aphanidermatum, P. spinosum and P. splendens were found to be highly aggressive at 25°C. However, the aggressiveness of P. spinosum decreased when the temperature was raised to 30°C, which was found to correspond to the lower frequency of isolation of P. spinosum in the warmer seasons, compared to the cooler time of the year. Pythium aphanidermatum exhibited limited intraspecific variation in the sequences of the ITS region of the rDNA and showed 100% similarity to the corresponding P. aphanidermatum sequences from GenBank. The ITS sequence data, as well as morphological characteristics of P. spinosum isolates, showed a high level of similarity within and between P. spinosum and P. kunmingense, and suggested that the two species were synonymous. This study represents the first report of P. spinosum, P. splendens and P. oligandrum in Oman.

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A total of 24 isolates of Pythium spinosum from cucumber obtained from five regions in Oman were characterized for genetic diversity using amplified fragment length polymorphism (AFLP) fingerprinting and three isolates from the Netherlands, South Africa and Japan were included for comparison. Isolates from Oman were also characterized for aggressiveness on cucumber seedlings and sensitivity to metalaxyl. Identity of all isolates was confirmed using sequences of the internal transcribed spacer (ITS) region of the ribosomal DNA (rDNA), which showed more than 99% nucleotide similarity among all isolates. Using six primer-pair combinations, AFLP fingerprinting resolved 295 AFLP markers of which 193 were polymorphic among isolates from other countries and only six were polymorphic among isolates of P. spinosum from Oman. Seven different AFLP phenotypes of P. spinosum were recovered in Oman; two of them were found to contain over 79% of isolates and one was recovered from all regions in Oman. Phenotypes from Oman showed very high (?99%) levels of genetic similarity to each other compared to moderate (mean =53%) levels of genetic similarity with phenotypes from other countries. In addition, all isolates from Oman were found to be highly sensitive to metalaxyl and all were aggressive on cucumber seedlings at 25°C. The high genetic similarity among phenotypes of P. spinosum in Oman as well as recovering two major clones across regions may suggest that P. spinosum has been recently introduced in Oman via a common source.

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In this paper, we tackle the problem of unsupervised domain adaptation for classification. In the unsupervised scenario where no labeled samples from the target domain are provided, a popular approach consists in transforming the data such that the source and target distributions be- come similar. To compare the two distributions, existing approaches make use of the Maximum Mean Discrepancy (MMD). However, this does not exploit the fact that prob- ability distributions lie on a Riemannian manifold. Here, we propose to make better use of the structure of this man- ifold and rely on the distance on the manifold to compare the source and target distributions. In this framework, we introduce a sample selection method and a subspace-based method for unsupervised domain adaptation, and show that both these manifold-based techniques outperform the cor- responding approaches based on the MMD. Furthermore, we show that our subspace-based approach yields state-of- the-art results on a standard object recognition benchmark.