122 resultados para I-3(-)
Resumo:
The ligands G1- and G2-oligo (benzyl ether) (PBE) dendrons and their iron(II) complexes [Fe(Gn-PBE)3]A2·xH2O (with n = 1, 2 and A = triflate, tosylate) were prepared. The magnetic properties of the complexes were investigated by a SQUID magnetometer. All complexes exhibit gradual spin transition below room temperature. At very low temperatures the magnetic behaviour reflects zero-field splitting (ZFS) effects. 57Fe-Mössbauer spectroscopy was performed to distinguish between ZFS of high spin species and spin state conversion into the low spin state. Further characterisation was carried out by thermogravimetric analysis (TGA) and FT-IR spectroscopy. Structural features have been determined by powder XRD measurements.
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4-Hexylbithienopyridine has been prepared as a novel electron-accepting monomer for conjugated polymers. To test its electronic properties, alternating copolymers with fluorene and indenofluorene polymers have been prepared. The copolymers displayed reduction potentials about 0.5 V lower than for the corresponding fluorene and indenofluorene homopolymers, indicating much improved electron-accepting properties. Analysis of the microscopic morphology of thin films of the copolymers by AFM shows that they lack the extensive supramolecular order seen with the homopolymers, which is attributed to the bithienopyridine units disrupting the π-stacking. LEDs using these polymers as the emitting layer produce blue-green emission with low turn-on voltages with aluminum electrodes confirming their improved electron affinity. The indenofluorene copolymer displayed an irreversible red shift in emission at high voltages, which is attributed to oxidation of the indenofluorene units. This red shift occurred at higher potentials than for indenofluorene homopolymers in LEDs, suggesting that the heterocyclic moieties offer some protection against electrically promoted oxidation.
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The characterization of human dendritic cell (DC) subsets is essential for the design of new vaccines. We report the first detailed functional analysis of the human CD141(+) DC subset. CD141(+) DCs are found in human lymph nodes, bone marrow, tonsil, and blood, and the latter proved to be the best source of highly purified cells for functional analysis. They are characterized by high expression of toll-like receptor 3, production of IL-12p70 and IFN-beta, and superior capacity to induce T helper 1 cell responses, when compared with the more commonly studied CD1c(+) DC subset. Polyinosine-polycytidylic acid (poly I:C)-activated CD141(+) DCs have a superior capacity to cross-present soluble protein antigen (Ag) to CD8(+) cytotoxic T lymphocytes than poly I:C-activated CD1c(+) DCs. Importantly, CD141(+) DCs, but not CD1c(+) DCs, were endowed with the capacity to cross-present viral Ag after their uptake of necrotic virus-infected cells. These findings establish the CD141(+) DC subset as an important functionally distinct human DC subtype with characteristics similar to those of the mouse CD8 alpha(+) DC subset. The data demonstrate a role for CD141(+) DCs in the induction of cytotoxic T lymphocyte responses and suggest that they may be the most relevant targets for vaccination against cancers, viruses, and other pathogens.
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Achieving business and IT integration is strategic goal for many organisations – it has almost become the ‘Holy Grail’ of organisational success. In this environment Enterprise Resource Planning (ERP) packages have become the defacto option for addressing this issue. Integration has come to mean adopting ERP, through configuration and without customization, but this all or nothing approach has proved difficult for many organisations. In part 1 of a 2 part update we provide evidence from the field that suggests that whilst costly, if managed appropriately, customization can have value in aiding organisational integration efforts. In part 2, we discuss in more detail the benefits and pitfalls involved in enacting a non-standard based integration strategy.
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A solo show by Courtney Coombs held at MetroArts in Brisbane as part of the 2011 Allies Program. The exhibtion comprised a series of sculptural, photographic, text and video works that each employed motifs evocative of romantic love combined with the artist self-effacing and ambivalent relationship to the art world and its male canon. The resulting exhibition acted as a meditation of female authorship in the studio and the contradictory impulses of critique and adoration.
Resumo:
This PhD research has provided novel solutions to three major challenges which have prevented the wide spread deployment of speaker recognition technology: (1) combating enrolment/ verification mismatch, (2) reducing the large amount of development and training data that is required and (3) reducing the duration of speech required to verify a speaker. A range of applications of speaker recognition technology from forensics in criminal investigations to secure access in banking will benefit from the research outcomes.
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New Dawn is a cross-media visual art project that comprises a multi–channel video work (Boxcopy ARI, Brisbane) and a series of sculptural works (MetroArts, Brisbane) both of which conflate the online spectacle of real events with virtual gaming. The purpose of this project is to question this new phenomenon and what are the political, social and economic repercussions for these new technological developments on our bodies and subjectivities. By doing this my work asks us to reflect on how we function as a society in response to these new spaces of interaction, how we might respond to the political dimensions of these expanded sites of inhabitation, and how they might also represent a more troubling scenario for the possibility of dissent or opposition in our media saturated culture. The work was shown at multiple venues simultaneously. One of the components of the work won the 2013 Sunshine Coast Art Prize for sculpture.
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PURPOSE: The prevalence of anaplastic lymphoma kinase (ALK) gene fusion (ALK positivity) in early-stage non-small-cell lung cancer (NSCLC) varies by population examined and detection method used. The Lungscape ALK project was designed to address the prevalence and prognostic impact of ALK positivity in resected lung adenocarcinoma in a primarily European population. METHODS: Analysis of ALK status was performed by immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) in tissue sections of 1,281 patients with adenocarcinoma in the European Thoracic Oncology Platform Lungscape iBiobank. Positive patients were matched with negative patients in a 1:2 ratio, both for IHC and for FISH testing. Testing was performed in 16 participating centers, using the same protocol after passing external quality assessment. RESULTS: Positive ALK IHC staining was present in 80 patients (prevalence of 6.2%; 95% CI, 4.9% to 7.6%). Of these, 28 patients were ALK FISH positive, corresponding to a lower bound for the prevalence of FISH positivity of 2.2%. FISH specificity was 100%, and FISH sensitivity was 35.0% (95% CI, 24.7% to 46.5%), with a sensitivity value of 81.3% (95% CI, 63.6% to 92.8%) for IHC 2+/3+ patients. The hazard of death for FISH-positive patients was lower than for IHC-negative patients (P = .022). Multivariable models, adjusted for patient, tumor, and treatment characteristics, and matched cohort analysis confirmed that ALK FISH positivity is a predictor for better overall survival (OS). CONCLUSION: In this large cohort of surgically resected lung adenocarcinomas, the prevalence of ALK positivity was 6.2% using IHC and at least 2.2% using FISH. A screening strategy based on IHC or H-score could be envisaged. ALK positivity (by either IHC or FISH) was related to better OS.
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Young novice drivers are at considerable risk of injury on the road. Their behaviour appears vulnerable to the social influence of their parents and friends. The nature and mechanisms of parent and peer influence on young novice driver (16–25 years) behaviour was explored via small group interviews (n = 21) and two surveys (n1 = 1170, n2 = 390) to inform more effective young driver countermeasures. Parental and peer influence occurred in preLicence, Learner, and Provisional (intermediate) periods. Pre-Licence and unsupervised Learner drivers reported their parents were less likely to punish risky driving (e.g., speeding). These drivers were more likely to imitate their parents and reported their parents were also risky drivers. Young novice drivers who experienced or expected social punishments from peers, including ‘being told off’ for risky driving, reported less riskiness. Conversely drivers who experienced or expected social rewards such as being ‘cheered on’ by friends – who were also more risky drivers – reported more risky driving including crashes and offences. Interventions enhancing positive influence and curtailing negative influence may improve road safety outcomes not only for young novice drivers, but for all persons who share the road with them. Parent-specific interventions warrant further development and evaluation including: modelling safe driving behaviour by parents; active monitoring of driving during novice licensure; and sharing the family vehicle during the intermediate phase. Peer-targeted interventions including modelling of safe driving behaviour and attitudes; minimisation of social reinforcement and promotion of social sanctions for risky driving also need further development and evaluation.
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A compelling body of studies identifies the importance of sleep for children’s learning, behavioral regulation, and health. These studies have primarily focused on nighttime sleep or on total sleep duration. The independent contribution of daytime sleep, or napping, in childhood is an emerging research focus. Daytime sleep is particularly pertinent to the context of early childhood education and care (ECEC) where, internationally, allocation of time for naps is commonplace through to the time of school entry. The biological value of napping varies with neurological maturity and with individual circumstance. Beyond the age of 3 years, when monophasic sleep patterns become typical, there is an increasing disjuncture between children’s normative sleep requirements and ECEC practice. At this time, research evidence consistently identifies an association between napping and decreased quality and duration of night sleep. We assess the implications of this evidence for educational practice and health policy. We identify the need to distinguish the functions of napping from those of rest, and assert the need for evidence-based guidelines on sleep–rest practices in ECEC settings to accommodate individual variation in sleep needs. Given both the evidence on the impact of children’s nighttime sleep on long-term trajectories of health and well-being and the high rates of child attendance in ECEC programs, we conclude that policy and practice regarding naptime have significant implications for child welfare and ongoing public health.
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The role that specific emotions, such as pride and triumph, play during instruction in science education is an under-researched field of study. Emotions are recognized as central to learning yet little is known about the way in which they are produced in naturalistic settings, how emotions relate to classroom learning during interactions, and what antecedent factors are associated with emotional experiences during instruction. Data sources for the study include emotion diaries, student written artifacts, video recordings of class interactions, and interviews. Emotions produced in the moment during classroom interactions are analyzed from video data and audio data through a novel theoretical framework related to the sociology of human emotions. These direct observations are compared with students’ recollected emotional experiences reported through emotion diaries and interviews. The study establishes links between pride and triumph within classroom interactions and instructional tasks during learning episodes in a naturalistic setting. We discuss particular classroom activities that are associated with justified feelings of pride and triumph. More specifically, classroom events associated with these emotions were related to understanding science concepts, social interactions, and achieving success on challenging tasks.
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The Guardian recently published an article by Nakkiah Lui, a Gamillaroi and Torres Strait Islander woman and writer, titled “Why this year’s NAIDOC week will be my last”. In response, Dr Chelsea Bond, an Aboriginal (Munanjahli) and South Sea Islander Australian and a senior lecturer with the Aboriginal and Torres Strait Islander Studies Unit at the University of Queensland, explains why she will continue to celebrate NAIDOC Week – as an act of agency.
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The predicted secondary structure of sub-genomic RNA in dengue virus defective interfering (D.I.) particles from patients, or generated in vitro, resembled that of the 3′ and 5′ regions of wild type dengue virus (DENV) genomes. While these structures in the sub-genomic RNA were found to be essential for its replication, their nucleotide sequences were not, so long as any new sequences maintained wild type RNA secondary structure. These observations suggested that these sub-genomic fragments of RNA from dengue viruses were replicated in the same manner as the full length genomes of their wild type, “helper”, viruses and that they probably represent the smallest fragments of DENV RNA that can be replicated during a natural infection. While D.I. particles containing sub-genomic RNA are completely parasitic, the relationship between wild type and D.I. DENV may be symbiotic, with the D.I. particles enhancing the transmission of infectious DENV.
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The early years are significant in optimising children’s educational, emotional and social outcomes and have become a major international policy priority. Within Australia, policy levers have prioritised early childhood education, with a focus on program quality, as it is associated with lifelong success. Longitudinal studies have found that high quality teacher-child interactions are an essential element of high quality programs, and teacher questioning is one aspect of teacher-child interactions that has been attributed to affecting the quality of education, linking open ended questioning to higher cognitive achievement. Teachers, however, overwhelmingly ask more closed than open questions. In the classroom, like everyday interaction, questions in interaction require answers. They are used to request, offer, repair, challenge, seek agreement (Curl & Drew, 2008; Enfield, Stivers, & Levinson, 2010; Hayano, 2013; Schegloff, 2007). Teachers use questions to set agendas and manage lessons (McHoul, 1978; Mehan, 1979; Sacks, 1995), and to gauge students’ knowledge and understanding (Lerner, 1995; McHoul, 1978; Mehan, 1979). Drawing on data from the Australian Research Council project Interacting with Knowledge: Interacting with people: Web searching in early childhood, this paper focuses on an extended sequence of talk between a teacher with two students aged between 3.5 and 5 years in a preschool classroom. The episode, drawn from a corpus of over 200 hours of video recorded data, captures how the teacher and children undertake an online search for images of lady beetles and hairy caterpillars on the Web. Ethnomethodological and conversation analysis approaches examine how the teacher asks questions, which call on the children to display their factual knowledge about the search topic. The fine grained analysis shows how teachers design their interactions to prompt children’s displays of factual knowledge, and how the design of factual questions affect a student’s response in terms of what and how they respond. In focussing on how the teacher designs factual questions and how children respond to these questions it shows that question design can close down a student’s reply; or elicit a range of answers, from one word to extended more detailed responses. Understanding how the design of teachers’ questions can influence students’ responses has pedagogic implications and may support educators to make intentional decisions regarding their own questioning techniques.