998 resultados para Long-song


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The main cis-acting control regions for replication of the single-stranded DNA genome of maize streak virus (MSV) are believed to reside within an approximately 310 nt long intergenic region (LIR). However, neither the minimum LIR sequence required nor the sequence determinants of replication specificity have been determined experimentally. There are iterated sequences, or iterons, both within the conserved inverted-repeat sequences with the potential to form a stem-loop structure at the origin of virion-strand replication, and upstream of the rep gene TATA box (the rep-proximal iteron or RPI). Based on experimental analyses of similar iterons in viruses from other geminivirus genera and their proximity to known Rep-binding sites in the distantly related mastrevirus wheat dwarf virus, it has been hypothesized that the iterons may be Rep-binding and/or -recognition sequences. Here, a series of LIR deletion mutants was used to define the upper bounds of the LIR sequence required for replication. After identifying MSV strains and distinct mastreviruses with incompatible replication-specificity determinants (RSDs), LIR chimaeras were used to map the primary MSV RSD to a 67 nt sequence containing the RPI. Although the results generally support the prevailing hypothesis that MSV iterons are functional analogues of those found in other geminivirus genera, it is demonstrated that neither the inverted-repeat nor RPI sequences are absolute determinants of replication specificity. Moreover, widely divergent mastreviruses can trans-replicate one another. These results also suggest that sequences in the 67 nt region surrounding the RPI interact in a sequence-specific manner with those of the inverted repeat.

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Recent studies demonstrated endogenous expression level of Sox2, Oct-4 and c-Myc is correlated with the pluripotency and successful induction of induced pluripotent stem cells (iPSCs). Periondontal ligament cells (PDLCs)have multi-lineage diferentiation capability and ability to maintain undifferentiated stage, which makes PDLCs a suitable cell source for tissue repair and regeneration. To elucidate the effect of in vitro culture condition on the stemness potential of PDLCs, we explored the cell growth, proliferation, cell cycle, and the expression of Sox2, Oct-4 and c-Myc in PDLCs from passage 1 to 7 with or without the addition of recombinant human BMP4(rhBMP4). Our results revealed that BMP-4 promoted cell growth and proliferation, arrested PDLCs in S phase of cell cycle and upregulated PI value. It was revealed that without the addition of rhBMP4, the expression of Sox2, Oct-4 and c-Myc in PDLCs only maintained nucleus location until passage 3, then lost nucleus location subsequently. The mRNA expression in PDLCs further confirmed that the level of Sox2 and Oct-4 peaked at passage 3, then decreased afterwards, whereas c-Myc maintained consistently upregulation along passages. after the treatment with rhBMP4, the expression of Sox2, Oct-4 and c-Myc in PDLCs maintained nucleus location even at passage 7 and the mRNA expression of Sox2 and Oct-4 significantly upregulated at passage 5 and 7. These results demonstrated that addition of rhBMP-4 in the culture media could improve the current culture condition for PDLCs to maintain in an undifferentiated stage.

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“Who are you? How do you define yourself, your identity?” With these words Allan Moore opens his exhaustive new work proposing a more comprehensive approach to the musicological analysis of popular song. The last three decades have seen a huge expansion of the anthology of the sociological and cultural meanings of pop, but Moore’s book is not another exploration of this field, although some of these ideas are incorporated in this work. Rather, he addresses the limitations of conventional musicology when dealing particularly with songs: “I address popular song rather than popular music. The defining feature of popular song lies in the interaction of everyday words and music… it is how they interact that produces significance in the experience of song”.

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The androgen receptor (AR) signaling pathway is a common therapeutic target for prostate cancer, because it is critical for the survival of both hormone-responsive and castrate-resistant tumor cells. Most of the detailed understanding that we have of AR transcriptional activation has been gained by studying classical target genes. For more than two decades, Kallikrein 3 (KLK3) (prostate-specific antigen) has been used as a prototypical AR target gene, because it is highly androgen responsive in prostate cancer cells. Three regions upstream of the KLK3 gene, including the distal enhancer, are known to contain consensus androgen-responsive elements required for AR-mediated transcriptional activation. Here, we show that KLK3 is one of a specific cluster of androgen-regulated genes at the centromeric end of the kallikrein locus with enhancers that evolved from the long terminal repeat (LTR) (LTR40a) of an endogenous retrovirus. Ligand-dependent recruitment of the AR to individual LTR-derived enhancers results in concurrent up-regulation of endogenous KLK2, KLK3, and KLKP1 expression in LNCaP prostate cancer cells. At the molecular level, a kallikrein-specific duplication within the LTR is required for maximal androgen responsiveness. Therefore, KLK3 represents a subset of target genes regulated by repetitive elements but is not typical of the whole spectrum of androgen-responsive transcripts. These data provide a novel and more detailed understanding of AR transcriptional activation and emphasize the importance of repetitive elements as functional regulatory units

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Allyson Reynolds, for many years now, has been a keen student of nature. Nature’s forms have always been important to her work, but it would be wrong to see Reynolds as simply transcribing directly from the natural world. For this artist, nature and the natural world represents an elusive invitation and so Reynolds doesn’t so much paint from nature, although resemblance and imitation are clearly evident, as work to render visually and emotionally tangible this invitation. And for a viewer this is no small thing as the invitation is to become attuned and connect with nature as it exists in ourselves, that is to see as nature. Reynolds’ is inviting us as viewers to connect and participate with the nature of nature that is evident in ourselves through the act of perceiving. Reynolds’ work can do this because it is a work born of deep evocation. The sensibility from which it emerges or is transacted is poetic, intensely so, but more than that it works to make of viewing an act of poetry, through a celebration of seeing. Reynolds evocation is born of a deep feeling towards and contemplation of the natural world - it is as though the world lives in her and is now a seamless part of her creative vocabulary. In such personal work there is a profoundly felt and revealed sense of the intimate and like true intimacy it revels in both its dark and quiet, as well as its playful and light, aspects. What is special about Reynolds’ visual poetry is that it able to render this intimacy so accessible. It is an accessibility that is available for the viewer who is able to not only look but also surrender to that looking, accepting and working with the flow of thoughts and associations it occasions...

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The current gold standard for the design of orthopaedic implants is 3D models of long bones obtained using computed tomography (CT). However, high-resolution CT imaging involves high radiation exposure, which limits its use in healthy human volunteers. Magnetic resonance imaging (MRI) is an attractive alternative for the scanning of healthy human volunteers for research purposes. Current limitations of MRI include difficulties of tissue segmentation within joints and long scanning times. In this work, we explore the possibility of overcoming these limitations through the use of MRI scanners operating at a higher field strength. We quantitatively compare the quality of anatomical MR images of long bones obtained at 1.5 T and 3 T and optimise the scanning protocol of 3 T MRI. FLASH images of the right leg of five human volunteers acquired at 1.5 T and 3 T were compared in terms of signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The comparison showed a relatively high CNR and SNR at 3 T for most regions of the femur and tibia, with the exception of the distal diaphyseal region of the femur and the mid diaphyseal region of the tibia. This was accompanied by an ~65% increase in the longitudinal spin relaxation time (T1) of the muscle at 3 T compared to 1.5 T. The results suggest that MRI at 3 T may be able to enhance the segmentability and potentially improve the accuracy of 3D anatomical models of long bones, compared to 1.5 T. We discuss how the total imaging times at 3 T can be kept short while maximising the CNR and SNR of the images obtained.

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The destination branding literature emerged as recently as 1998, and there remains a dearth of empirical data that tests the effectiveness of brand campaigns over time. This paper reports the results of an investigation into consumer-based brand equity for Australia as a long haul destination in an emerging South American market. In spite of the high level of academic interest in the measurement of perceptions of destinations since the 1970s, few previous studies have examined perceptions held by South American consumers. Findings suggest that destination brand awareness, brand image, and brand value are positively related to brand loyalty for a long-haul destination. The results also indicate that Australia is a more compelling destination brand for previous visitors compared to non-visitors.

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Pumice is an extremely effective rafting agent that can dramatically increase the dispersal range of a variety of marine organisms and connect isolated shallow marine and coastal ecosystems. Here we report on a significant recent pumice rafting and long-distance dispersal event that occurred across the southwest Pacific following the 2006 explosive eruption of Home Reef Volcano in Tonga. We have constrained the trajectory, and rate, biomass and biodiversity of transfer, discovering more than 80 species and a substantial biomass underwent a .5000 km journey in 7–8 months. Differing microenvironmental conditions on the pumice, caused by relative stability of clasts at the sea surface, promoted diversity in biotic recruitment. Our findings emphasise pumice rafting as an important process facilitating the distribution of marine life, which have implications for colonisation processes and success, the management of sensitive marine environments, and invasive pest species.

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The study of destination brand performance measurement has only emerged in earnest as a field in the tourism literature since 2007. The concept of consumer-based brand equity (CBBE) is gaining favour from services marketing researchers as an alternative to the traditional ‘net-present-value of future earnings’ method of measuring brand equity. The perceptions-based CBBE model also appears suitable for examining destination brand performance, where a financial brand equity valuation on a destination marketing organisation’s (DMO) balance sheet is largely irrelevant. This is the first study to test and compare the model in both short and long haul markets. The paper reports the results of tests of a CBBE model for Australia in a traditional short haul market (New Zealand) and an emerging long haul market (Chile). The data from both samples indicated destination brand salience, brand image, and brand value are positively related to purchase intent for Australia in these two disparate markets.

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Time and space are fundamental to human language and embodied cognition. In our early work we investigated how Lingodroids, robots with the ability to build their own maps, could evolve their own geopersonal spatial language. In subsequent studies we extended the framework developed for learning spatial concepts and words to learning temporal intervals. This paper considers a new aspect of time, the naming of concepts like morning, afternoon, dawn, and dusk, which are events that are part of day-night cycles, but are not defined by specific time points on a clock. Grounding of such terms refers to events and features of the diurnal cycle, such as light levels. We studied event-based time in which robots experienced day-night cycles that varied with the seasons throughout a year. Then we used meet-at tasks to demonstrate that the words learned were grounded, where the times to meet were morning and afternoon, rather than specific clock times. The studies show how words and concepts for a novel aspect of cyclic time can be grounded through experience with events rather than by times as measured by clocks or calendars

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Objective: Several new types of contraception became available in Australia over the last twelve years (the implant in 2001, progestogen intra-uterine device (IUD) in 2003, and vaginal contraceptive ring in 2007). Most methods of contraception require access to health services. Permanent sterilisation and the insertion of an implant or IUD involve a surgical procedure. Access to health professionals providing these specialised services may be more difficult in rural areas. This paper examines uptake of permanent or long-acting reversible contraception (LARCs) among Australian women in rural areas compared to women in urban areas. Method: Participants in the Australian Longitudinal Study on Women's Health born in 1973-78 reported on their contraceptive use at three surveys: 2003, 2006 and 2009. Contraceptive methods included permanent sterilisation (tubal ligation, vasectomy), non-daily or LARC methods (implant, IUD, injection, vaginal ring), and other methods including daily, barrier or "natural" methods (oral contraceptive pills, condoms, withdrawal, safe period). Sociodemographic, reproductive history and health service use factors associated with using permanent, LARC or other methods were examined using a multivariable logistic regression analysis. Results: Of 9,081 women aged 25-30 in 2003, 3% used permanent methods and 4% used LARCs. Six years later in 2009, of 8,200 women (aged 31-36), 11% used permanent methods and 9% used LARCs. The fully adjusted parsimonious regression model showed that the likelihood of a woman using LARCs and permanent methods increased with number of children. Women whose youngest child was school-age were more likely to use LARCs (OR=1.83, 95%CI 1.43-2.33) or permanent methods (OR=4.39, 95%CI 3.54-5.46) compared to women with pre-school children. Compared to women living in major cities, women in inner regional areas were more likely to use LARCs (OR=1.26, 95%CI 1.03-1.55) or permanent methods (OR=1.43, 95%CI 1.17-1.76). Women living in outer regional and remote areas were more likely than women living in cities to use LARCs (OR=1.65, 95%CI 1.31-2.08) or permanent methods (OR=1.69, 95%CI 1.43-2.14). Women with poorer access to GPs were more likely to use permanent methods (OR=1.27, 95%CI 1.07-1.52). Conclusions: Location of residence and access to health services are important factors in women's choices about long-acting contraception in addition to the number and age of their children. There is a low level of uptake of non-daily, long-acting methods of contraception among Australian women in their mid-thirties.

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In this paper we demonstrate passive vision-based localization in environments more than two orders of magnitude darker than the current benchmark using a 100 webcam and a 500 camera. Our approach uses the camera’s maximum exposure duration and sensor gain to achieve appropriately exposed images even in unlit night-time environments, albeit with extreme levels of motion blur. Using the SeqSLAM algorithm, we first evaluate the effect of variable motion blur caused by simulated exposures of 132 ms to 10000 ms duration on localization performance. We then use actual long exposure camera datasets to demonstrate day-night localization in two different environments. Finally we perform a statistical analysis that compares the baseline performance of matching unprocessed greyscale images to using patch normalization and local neighbourhood normalization – the two key SeqSLAM components. Our results and analysis show for the first time why the SeqSLAM algorithm is effective, and demonstrate the potential for cheap camera-based localization systems that function across extreme perceptual change.

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Over the past two decades medical researchers and modernist feminist researchers have contested the meaning of menopause. In this article we examine various meanings of menopause in major medical and feminist literature and the construction of menopause in a semi-structured interview study of general practitioners in rural South Australia. Three discursive themes are identified in these interviews; (i) the hormonal menopause – symptoms, risk, prevention; (ii) the informed menopausal woman; and (iii) decision-making and hormone replacement therapy. By using the discourse of prevention, general practitioners construct menopause in relation to women's health care choices, empowerment and autonomy. We argue that the ways in which these concepts are deployed by general practitioners in this study produces and constrains the options available to women. The implications of these general practitioner accounts are discussed in relation to the proposition that medical and feminist descriptions of menopause posit alternative but equally-fixed truths about menopause and their relationship with the range of responses available to women at menopause. Social and cultural explanations of disease causality (c.f.Germov 1998, Hardey 1998) are absent from the new menopause despite their being an integral part of the framework of the women's health movement and health promotion drawn on by these general practitioners. Further, the shift of responsibility for health to the individual woman reinforces practice claims to empower women, but oversimplifies power relations and constructs menopause as a site of self-surveillance. The use of concepts from the women's health movement and health promotion have nevertheless created change in both the positioning of women as having ‘choices’ and the positioning of some general practitioners in terms of greater information provision to women and an attention to the woman's autonomy. In conclusion, we propose that a new menopause has evolved from a discursive shift in medicine and that there exists within this new configuration, claiming the empowerment of women as an integral part of health care for menopause, the possibility for change in medical practice which will broaden, strengthen, and maintain this position.