954 resultados para motivation-relevant affective conditions


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This guide is to support institutions in developing and teaching tertiary level programmes for sustainable energy professionals. Ongoing curriculum renewal is more difficult but vital for multidisciplinary courses preparing graduates to work in a specialised rapidly changing field. After more than 15 years of offering tertiary level “sustainable energy” qualifications in Australian Universities there was a clear need to assess how these courses are taught and develop curriculum frameworks to guide Universities designing/redesigning programs and courses to provide graduates with the relevant skills, knowledge and attributes (capabilities) seen by graduates and employers as required to work in this rapidly changing field. This guide presents the sustainable energy curriculum frameworks developed by the “Renewing the sustainable energy curriculum – providing internationally relevant skills for a carbon constrained economy” project, which was conducted over a two-and-a-quarter year period.

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Over the past decade, enrolments in postgraduate courses in Australian universities have risen by 34% (or from 258,164 in 2004 to 347,363 in 2013) (uCube, 2014). This substantial growth can be attributed to increased demand for postgraduate coursework as continuing professional education, the expansion of Higher Degrees Research (HDR) intakes, and the development of postgraduate research and coursework degrees in new fields. At the same time, the establishment of the Australian Qualification Framework (AQF) and national Tertiary Education Quality and Standards Agency (TEQSA), as well as the internationalisation of postgraduate education, have brought challenges and opportunities to the sector. During the past five years, the Australian Government Office for Learning and Teaching (OLT) and its predecessor bodies have funded a number of projects and Fellowships on postgraduate coursework and research degrees. They span diverse topics–from entry pathways and research training to supporting international and Indigenous students, examination, scoping studies of new and emergent programs, and effective supervision. In 2014 the OLT commissioned this good practice report to review the grants and fellowships conducted between 2009 and 2014. Encompassing twenty-seven learning and teaching projects and fellowships, the aims of this report include providing universities and academics with an overview of the current state of postgraduate study in Australia and the major influences upon it; a coherent overview of funded projects’ findings and outcomes; and a central point to access good practices, resources and tools in summary form. The objectives of this good practice report are to provide: • A literature review, which contextualises the projects within the Australian and international Higher Education environment, emphasises factors that currently influence postgraduate programs, and highlights challenges and opportunities for the sector. It also explains variations in postgraduate course types and definitions within the Australian Qualification Framework (AQF), and identifies key learning and teaching issues as well as good practices identified in scholarly research and position papers. • A collated overview of the twenty-seven national learning and teaching projects and fellowships on postgraduate coursework and research, including a summary of each project’s aims and objectives, methodologies, outcomes and resources. • A summative index of project characteristics (topics, themes and approaches) and inventory of scholarly research outcomes of the completed projects (publications, reports) as well as resources produced (tools, methods, good practice case studies), and their location (URL Links, references, etc.). • A summary of good practices that have been identified from the literature and the findings of completed projects. • A set of recommendations to address remaining gaps in the field and areas in which further work or development are appropriate. Bringing this work together will help enable university course teams to improve the delivery and development of existing postgraduate courses and to develop new ones, and it will provide academics with an overview of good practices and resources for teaching, supervising and supporting postgraduate students.

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The aim of this study is to identify current knowledge gaps in fate, exposure, and toxicity of engineered nanomaterials (ENMs), highlight research gaps, and suggest future research directions. Humans and other living organisms are exposed to ENMs during production or use of products containing them. To assess the hazards of ENMs, it is important to assess their physiochemical properties and try to relate them to any observed hazard. However, the full determination of these relationships is currently limited by the lack of empirical data. Moreover, most toxicity studies do not use realistic environmental exposure conditions for determining dose-response parameters, affecting the accurate estimation of health risks associated with the exposure to ENMs. Regulatory aspects of nanotechnology are still developing and are currently the subject of much debate. Synthesis of available studies suggests a number of open questions. These include (i) developing a combination of different analytical methods for determining ENM concentration, size, shape, surface properties, and morphology in different environmental media, (ii) conducting toxicity studies using environmentally relevant exposure conditions and obtaining data relevant to developing quantitative nanostructure-toxicity relationships (QNTR), and (iii) developing guidelines for regulating exposure of ENMs in the environment.

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This paper describes the authors’ distributed parameter approach for derivation of closed-form expressions for the four-pole parameters of the perforated three-duct muffler components. In this method, three simultaneous second-order partial differential equations are first reduced to a set of six first-order ordinary differential equations. These equations are then uncoupled by means of a modal matrix. The resulting 6 × 6 matrix is reduced to the 2 × 2 transfer matrix using the relevant boundary conditions. This is combined with transfer matrices of other elements (upstream and downstream of this perforated element) to predict muffler performance like noise reduction, which is also measured. The correlation between experimental and theoretical values of noise reduction is shown to be satisfactory.

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Acoustic radiation from a spherical source undergoing angularly periodic axisymmetric harmonic surface vibrations while eccentrically suspended within a thermoviscous fluid sphere, which is immersed in a viscous thermally conducting unbounded fluid medium, is analyzed in an exact fashion. The formulation uses the appropriate wave-harmonic field expansions along with the translational addition theorem for spherical wave functions and the relevant boundary conditions to develop a closed-form solution in form of infinite series. The analytical results are illustrated with a numerical example in which the vibrating source is eccentrically positioned within a chemical fluid sphere submerged in water. The modal acoustic radiation impedance load on the source and the radiated far-field pressure are evaluated and discussed for representative values of the parameters characterizing the system. The proposed model can lead to a better understanding of dynamic response of an underwater acoustic lens. It is equally applicable in miniature transducer analysis and design with applications in medical ultrasonics.

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There are a lot of differences in the neural mechanisms underlying between drug reward and natural reward despite the common neual basis. Undoubtedly, revealing the common and the different mechanisms underlying drug reward and natural reward will promote the development of research on drug addiction. Among diversified natural rewards, sex is often compared to drug because sexual reward has more similarities to drug. The mesolimbic dopamine system (VTA-NAc pathway) is a common pathway activated by natural reinforcers and addictive drugs, mediating reward, emotion and motivation under physiological conditions. The neuroadaptations taking place in the central nervous system including the mesolimbic dopamine system after repeatedly drug taking leads to persistent drug craving, Orexin, a neuropeptide produced in the lateral hypothalamus, plays an important role in reward-associated, motivated behaviors. Orexin neurons have extensive projections to the mesolimbic dopamine system. In order to further investigate the roles of orexin A in drug reward, this study examined the regulatory roles of orexin A in the VTA and NAcSh on drug reinforcement (acqusition of morphine CPP) and drug-seeking behavior (expression of morphine CPP). Moreover, the roles of orexin A on drug reward were compared with sexual reward. The main results are as follows: 1. The expression of morphine CPP was inhibited by intracerebroventricularly (i.c.v.) administered OX1R antagonist SB334867; 2. The male unconditioned sexual motivation was not affected by i.c.v. administered SB334867. However, i.c.v. given orexin A inhibited unconditioned sexual motivation in sexually high-motivated rats but did not affect sexual motivation in low-motivated rats; 3. The acquisition and expression of morphine CPP was inhibited by SB334867 microinjected into the VTA. SB334867 or orexin A injected into the NAcSh did not influence the acquisition of morphine CPP, but orexin A increased the locomotor activity in rats treated with morphine (3mg/kg); 4. SB334867 microinjected into the VTA did not affect male copulatory behavior, neither affect the acqusition of copulatory CPP; 5. The expression of copulatory CPP was associated with increased Fos protein expression in hypothalamic orexin A neurons, and SB334867 microinjected into the VTA inhibited expression of copulatory CPP. These results suggest that, (1) endogenous orexin A is not involved in male unconditioned sexual motivation, but involved in drug craving; (2) orexin A in the VTA instead of in the NAc is involved in drug reinforcement; (3) orexin A in the VTA is critical for drug-seeking behavior, but it is still unclear for the role of orexin A in the NAcSh; (4) in contrast to drug reinforcement, orexin A in the VTA is not involved in reinforcing effect of sexual reward. Orexin A plays a role both in drug-seeking behavior and in sexual reward-seeking behavior, but the different orexin A neuron populations may be responsible for the roles of orexin A in two types of reward. In a word, the differential roles of orexin A in drug and sexual reward are found in the present study, which provides some evidence for further research on the mechanisms of drug addiction.

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Cronobacter spp. are opportunistic pathogens which can be isolated from a wide variety of foods and environments. They are Gram negative, motile, non-spore forming, peritrichous rods of the Enterobacteriaceae family. This food-borne pathogen is associated with the ingestion of contaminated infant milk formula (IMF), causing necrotizing enterocolitis, sepsis and meningitis in neonatal infants. The work presented in this thesis involved the investigation and characterisation of a bank of Cronobacter strains for their ability to tolerate physiologically relevant stress conditions that are commonly encountered in the gastrointestinal tract. While all strains were able to endure the suboptimal conditions tested, noteworthy variations were observed between strains. A collection of these strains were Lux-tagged to determine if their growth could be tracked in IMF by measuring bioluminescence. The resulting strains could be easily and reproducibly monitored in real time by measuring light emission. Following this a transposon mutagenesis library was created in one of the Lux-tagged strains of Cronobacter sakazakii. This library was screened for mutants with affected growth in milk. The majority of mutants identified were associated with amino acid metabolism. The final section of this thesis identified genes involved in the tolerance of C. sakazakii to the milk derived antimicrobial peptide, Lactoferricin B (Lfcin B). This was achieved by creating a transposon mutagenesis library in C. sakazakii and screening for mutants with increased susceptibility to Lfcin B. Overall this thesis demonstrates the variation between Cronobacter strains. It also identifies genes required for growth of the bacteria in milk, as well as genes needed for antimicrobial peptide tolerance.

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Cryptococcus neoformans is a prevalent human fungal pathogen that must survive within various tissues in order to establish a human infection. We have identified the C. neoformans Rim101 transcription factor, a highly conserved pH-response regulator in many fungal species. The rim101 multiply sign in circle mutant strain displays growth defects similar to other fungal species in the presence of alkaline pH, increased salt concentrations, and iron limitation. However, the rim101 multiply sign in circle strain is also characterized by a striking defect in capsule, an important virulence-associated phenotype. This capsular defect is likely due to alterations in polysaccharide attachment to the cell surface, not in polysaccharide biosynthesis. In contrast to many other C. neoformans capsule-defective strains, the rim101 multiply sign in circle mutant is hypervirulent in animal models of cryptococcosis. Whereas Rim101 activation in other fungal species occurs through the conserved Rim pathway, we demonstrate that C. neoformans Rim101 is also activated by the cAMP/PKA pathway. We report here that C. neoformans uses PKA and the Rim pathway to regulate the localization, activation, and processing of the Rim101 transcription factor. We also demonstrate specific host-relevant activating conditions for Rim101 cleavage, showing that C. neoformans has co-opted conserved signaling pathways to respond to the specific niche within the infected host. These results establish a novel mechanism for Rim101 activation and the integration of two conserved signaling cascades in response to host environmental conditions.

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Determination of metal oxidation state under relevant working conditions is crucial to understand catalytic behaviour. The reduction behaviour of Pt and Re was evaluated simultaneously as a function of support and solvent in a pressurized reactor (autoclave). The bimetallic catalysts are used in selective hydrogenation of carboxylic acids and amides. Gas phase reduction reduced the metals more efficiently, in particular Pt.

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Environmental contamination and climate changes constitute two of the most serious problems affecting soil ecosystems in agricultural fields. Agriculture is nowadays a highly optimized process that strongly relies on the application of multiple pesticides to reduce losses and increase yield production. Although constituting, per se, a serious problem to soil biota, pesticide mixtures can assume an even higher relevance in a context of unfavourable environmental conditions. Surprisingly, frameworks currently established for environmental risk assessments keep not considering environmental stressors, such as temperature, soil moisture or UV radiation, as factors liable to influence the susceptibility of organisms to pesticides, or pesticide mixtures, which is raising increasing apprehension regarding their adequacy to actually estimate the risks posed by these compounds to the environment. Albeit the higher attention received on the last few years, the influence of environmental stressors on the behaviour and toxicity of chemical mixtures remains still poorly understood. Aiming to contribute for this discussion, the main goal of the present thesis was to evaluate the single and joint effects of natural stressors and pesticides to the terrestrial isopod Porcellionides pruinosus. The first approach consisted on evaluating the effects of several abiotic factors (temperature, soil moisture and UV radiation) on the performance of P. pruinosus using several endpoints: survival, feeding parameters, locomotor activity and avoidance behaviour. Results showed that these stressors might indeed affect P. pruinosus at relevant environmental conditions, thus suggesting the relevance of their consideration in ecotoxicological assays. At next, a multiple biomarker approach was used to have a closer insight into the pathways of damage of UV radiation and a broad spectrum of processes showed to be involved (i.e. oxidative stress, neurotoxicity, energy). Furthermore, UV effects showed to vary with the environment medium and growth-stage. A similar biomarker approach was employed to assess the single and joint effects of the pesticides chlorpyrifos and mancozeb to P. pruinosus. Energy-related biomarkers showed to be the most differentiating parameters since age-classes seemed to respond differently to contamination stress and to have different metabolic costs associated. Finally, the influence of temperature and soil moisture on the toxicity of pesticide mixtures was evaluated using survival and feeding parameters as endpoints. Pesticide-induced mortality was found to be oppositely affected by temperature, either in single or mixture treatments. Whereas chlorpyrifos acute toxicity was raised under higher temperatures the toxicity of mancozeb was more prominent at lower temperatures. By the opposite, soil moisture showed no effects on the pesticide-induced mortality of isopods. Contrary to survival, both temperature and soil moisture showed to interact with pesticides to influence isopods’ feeding parameters. Nonetheless, was however the most common pattern. In brief, findings reported on this thesis demonstrated why the negligence of natural stressors, or multiple stressors in general, is not a good solution for risk assessment frameworks.

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In marine benthic communities, herbivores consume a considerable proportion of primary producer biomass and, thus, generate selection for the evolution of resistance traits. According to the theory of plant defenses, resistance traits are costly to produce and, consequently, inducible resistance traits are adaptive in conditions of variable herbivory, while in conditions of constant/strong herbivory constitutive resistance traits are selected for. The evolution of resistance plasticity may be constrained by the costs of resistance or lack of genetic variation in resistance. Furthermore, resource allocation to induced resistance may be affected by higher trophic levels preying on herbivores. I studied the resistance to herbivory of a foundation species, the brown alga Fucus vesiculosus. By using factorial field experiments, I explored the effects of herbivores and fish predators on growth and resistance of the alga in two seasons. I explored genetic variation in and allocation costs of resistance traits as well as their chemical basis and their effects on herbivore performance. Using a field experiment I tested if induced resistance spreads via water-borne cues from one individual to another in relevant ecological conditions. I found that in the northern Baltic Sea F. vesiculosus communities, strength of three trophic interactions strongly vary among seasons. The highly synchronized summer reproduction of herbivores promoted their escape from the top-down control of fish predators in autumn. This resulted into large grazing losses in algal stands. In spring, herbivore densities were low and regulated by fish, which, thus,enhanced algal growth. The resistance of algae to herbivory increased with an increase in constitutive phlorotannin content. Furthermore, individuals adopted induced resistance when grazed and when exposed to water-borne cues originating from grazing of conspecific algae both in the laboratory and in field conditions. Induced resistance was adopted to a lesser extent in the presence of fish predators. The results in this thesis indicate that inducible resistance in F. vesiculosus is an adaptation to varying herbivory in the northern Baltic Sea. The costs of resistance and strong seasonality of herbivory have likely contributed to the evolution of this defense strategy. My findings also show that fish predators have positive cascading effects on F. vesiculosus which arise via reduced herbivory but possibly also through reduced resource allocation to resistance. I further found evidence that the spread of resistance via water-borne cues also occurs in ecologically realistic conditions in natural marine sublittoral. Thus, water-borne induction may enable macroalgae to cope with the strong grazing pressure characteristic of marine benthic communities. The results presented here show that seasonality can have pronounced effects on the biotic interactions in marine benthic communities and thereafter influence the evolution of resistance traits in primary producers.

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Les amidons non modifiées et modifiés représentent un groupe d’excipients biodégradables et abondants particulièrement intéressant. Ils ont été largement utilisés en tant qu’excipients à des fins diverses dans des formulations de comprimés, tels que liants et/ou agents de délitement. Le carboxyméthylamidon sodique à haute teneur en amylose atomisé (SD HASCA) a été récemment proposé comme un excipient hydrophile à libération prolongée innovant dans les formes posologiques orales solides. Le carboxyméthylamidon sodique à haute teneur en amylose amorphe (HASCA) a d'abord été produit par l'éthérification de l'amidon de maïs à haute teneur en amylose avec le chloroacétate. HASCA a été par la suite séché par atomisation pour obtenir le SD HASCA. Ce nouvel excipient a montré des propriétés présentant certains avantages dans la production de formes galéniques à libération prolongée. Les comprimés matriciels produits à partir de SD HASCA sont peu coûteux, simples à formuler et faciles à produire par compression directe. Le principal objectif de cette recherche était de poursuivre le développement et l'optimisation des comprimés matriciels utilisant SD HASCA comme excipient pour des formulations orales à libération prolongée. A cet effet, des tests de dissolution simulant les conditions physiologiques du tractus gastro-intestinal les plus pertinentes, en tenant compte de la nature du polymère à l’étude, ont été utilisés pour évaluer les caractéristiques à libération prolongée et démontrer la performance des formulations SD HASCA. Une étude clinique exploratoire a également été réalisée pour évaluer les propriétés de libération prolongée de cette nouvelle forme galénique dans le tractus gastro-intestinal. Le premier article présenté dans cette thèse a évalué les propriétés de libération prolongée et l'intégrité physique de formulations contenant un mélange comprimé de principe actif, de chlorure de sodium et de SD HASCA, dans des milieux de dissolution biologiquement pertinentes. L'influence de différentes valeurs de pH acide et de temps de séjour dans le milieu acide a été étudiée. Le profil de libération prolongée du principe actif à partir d'une formulation de SD HASCA optimisée n'a pas été significativement affecté ni par la valeur de pH acide ni par le temps de séjour dans le milieu acide. Ces résultats suggèrent une influence limitée de la variabilité intra et interindividuelle du pH gastrique sur la cinétique de libération à partir de matrices de SD HASCA. De plus, la formulation optimisée a gardé son intégrité pendant toute la durée des tests de dissolution. L’étude in vivo exploratoire a démontré une absorption prolongée du principe actif après administration orale des comprimés matriciels de SD HASCA et a montré que les comprimés ne se sont pas désintégrés en passant par l'estomac et qu’ils ont résisté à l’hydrolyse par les α-amylases dans l'intestin. Le deuxième article présente le développement de comprimés SD HASCA pour une administration orale une fois par jour et deux fois par jour contenant du chlorhydrate de tramadol (100 mg et 200 mg). Ces formulations à libération prolongée ont présenté des valeurs de dureté élevées sans nécessiter l'ajout de liants, ce qui facilite la production et la manipulation des comprimés au niveau industriel. La force de compression appliquée pour produire les comprimés n'a pas d'incidence significative sur les profils de libération du principe actif. Le temps de libération totale à partir de comprimés SD HASCA a augmenté de manière significative avec le poids du comprimé et peut, de ce fait, être utilisé pour moduler le temps de libération à partir de ces formulations. Lorsque les comprimés ont été exposés à un gradient de pH et à un milieu à 40% d'éthanol, un gel très rigide s’est formé progressivement sur leur surface amenant à la libération prolongée du principe actif. Ces propriétés ont indiqué que SD HASCA est un excipient robuste pour la production de formes galéniques orales à libération prolongée, pouvant réduire la probabilité d’une libération massive de principe actif et, en conséquence, des effets secondaires, même dans le cas de co-administration avec une forte dose d'alcool. Le troisième article a étudié l'effet de α-amylase sur la libération de principe actif à partir de comprimés SD HASCA contenant de l’acétaminophène et du chlorhydrate de tramadol qui ont été développés dans les premières étapes de cette recherche (Acetaminophen SR et Tramadol SR). La modélisation mathématique a montré qu'une augmentation de la concentration d’α-amylase a entraîné une augmentation de l'érosion de polymère par rapport à la diffusion de principe actif comme étant le principal mécanisme contrôlant la libération de principe actif, pour les deux formulations et les deux temps de résidence en milieu acide. Cependant, même si le mécanisme de libération peut être affecté, des concentrations d’α-amylase allant de 0 UI/L à 20000 UI/L n'ont pas eu d'incidence significative sur les profils de libération prolongée à partir de comprimés SD HASCA, indépendamment de la durée de séjour en milieu acide, le principe actif utilisé, la teneur en polymère et la différente composition de chaque formulation. Le travail présenté dans cette thèse démontre clairement l'utilité de SD HASCA en tant qu'un excipient à libération prolongée efficace.

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We study the topology of a set naturally arising from the study of β-expansions. After proving several elementary results for this set we study the case when our base is Pisot. In this case we give necessary and sufficient conditions for this set to be finite. This finiteness property will allow us to generalise a theorem due to Schmidt and will provide the motivation for sufficient conditions under which the growth rate and Hausdorff dimension of the set of β-expansions are equal and explicitly calculable.

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Child facial cues evoke attention, parental care behaviors and modulate for infant- caretaker interactions. Lorenz described the baby schema ( Kindchenschema ) as a set of infantile physical features such as the large head, round face, high and protruding forehead, big eyes, chubby cheeks, small nose and mouth. Previous work on this fundamental concept was restricted to positive perception to infant face, and did not show consistent results about the development individuals perceptions, regarding the physical attributes that worked as markers of cuteness. Here, we experimentally tested the effects of baby schema on the perception of cuteness of infant faces by children and adults. We used 60 none graphically manipulated photos of different stimulus children faces from 4 to 9 years old. In the first task for the adults experimental subjects, ten stimulus photos were shown, whereas for children experimental subjects, four stimulus photos were shown at a time, with a total of six rounds. The second task involved only adults, who indicated the motivation of affective behaviors and care directed to children through a Likert scale. Our results suggest that both participants judged similarly the cuteness of children's faces, and the physical features markers of this perception were observed only for younger stimulus children. Adults have attributed more motivations of positive behaviors to cuter stimulus children. The recognition of the baby schema by individuals of different ages and genders confers the universality and power of children's physical attributes. From the evolutionary perspective the responsiveness to baby schema is significant to ensure aloparental and parental investment, and the consequent children survival

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Docking simulations have been used to assess protein complexes with some success. Small angle X-ray scattering (SAXS) is a well-established technique to investigate protein spatial configuration. This work describes the integration of geometric docking with SAXS to investigate the quaternary structure of recombinant human purine nucleoside phosphorylase (PNP). This enzyme catalyzes the reversible phosphorolysis of N-ribosidic bonds of purine nucleosides and deoxynucleosides. A genetic deficiency due to mutations in the gene encoding for PNP causes gradual decrease in T-cell immunity. Inappropriate activation of T-cells has been implicated in several clinically relevant human conditions such as transplant rejection, rheumatoid arthritis, lupus, and T-cell lymphomas. PNP is therefore a target for inhibitor development aiming at T-cell immune response modulation and has been submitted to extensive structure-based drug design. The present analysis confirms the trimeric structure observed in the crystal. The potential application of the present procedure to other systems is discussed. (C) 2003 Elsevier B.V. All rights reserved.