186 resultados para rearranged (4 -> 2)-abeo-clerodane
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Density functional calculations of the electronic band structure for superconducting and semi-conducting metal hexaborides are compared using a consistent suite of assumptions and with emphasis on the physical implications of computed models. Spin polarization enhances mathematical accuracy of the functional approximations and adds significant physical meaning to model interpretation. For YB6 and LaB6, differences in alpha and beta projections occur near the Fermi energy. These differences are pronounced for superconducting hexaborides but do not occur for other metal hexaborides.
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Seven new and three known bisresorcinols, grevirobstol A(=5,5'-((6Z,9Z)-hexadeca-6,9-diene-1,16-diyl)bisresorcinol; 8), 5,5'-[(8Z)-hexadec-8-ene-1,16-diyl]bisresorcinol (9), and 2-methyl-5,5'-[8Z)-hexadec-8-ene-1,16-diyl] bisresorcinol (10) were isolated from the stems of Grevillea glauca. The new compounds were identified on the basis of spectroscopic data as (Z)-6,7-didehydroglaucone A (1), glaucones A and B (2 and 3, resp.), 2-(3-hydroxyisopentyl)bisnorstriatol (4), 2-(3-methylbut-2-en-1-yl)bisnorstriatol (5), 2'-methylgrebustol A (6), and glaucane (7).
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This article explores how the imaginative use of the landscape in Baz Luhrmann’s Australia (2008) intersects with the fantasy of Australianness that the film constructs. We argue the fictional Never-Never Land through which the film’s characters travel is an, albeit problematic, ‘indigenizing’ space that can be entered imaginatively through cultural texts including poetry, literature and film, or through cultural practices including touristic pilgrimages to landmarks such as Uluru and Kakadu National Park. These actual and virtual journeys to the Never-Never have broader implications in terms of fostering a sense of belonging and legitimating white presence in the land through affect, nostalgia and the invocation of an imagined sense of solidarity and community. The heterotopic concept of the Never-Never functions to create an ahistorical, inclusive space that grounds diverse conceptions of Australianness in a shared sense of belonging and home that is as mythical, contradictory and wondrous as the idea of the Never-Never itself. The representations of this landscape and the story of the characters that traverse it self-consciously construct a relationship to past events and to film history, as well as constructing a comfortable subject position for contemporary Australians to occupy in relation to the land, the colonial past, and the present.
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Many activities, from disaster response to project management, require cooperation among people from multiple organizations who initially lack interpersonal relationships and trust. Upon entering inter-organizational settings, pre-existing identities and expectations, along with emergent social roles and structures, may all influence trust between colleagues. To sort out these effects, we collected time-lagged data from three cohorts of military MBA students, representing 2,224 directed dyads, shortly after they entered graduate school. Dyads that shared organizational identity, boundary-spanning roles, and similar network positions (structural equivalence) were likely to have stronger professional ties and greater trust.
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We have studied a mineral sample of mottramite PbCu(VO4)(OH) from Tsumeb, Namibia using a combination of scanning electron microscopy with EDX, Raman and infrared spectroscopy. Chemical analysis shows principally the elements V, Pb and Cu. Ca occurs as partial substitution of Pb as well as P and As in substitution to V. Minor amounts of Si and Cr were also observed. The Raman band of mottramite at 829 cm-1, is assigned to the ν1 symmetric (VO-4) ) stretching mode. The complexity of the spectra is attributed to the chemical composition of the Tsumeb mottramite. The ν3 antisymmetric vibrational mode of mottramite is observed as very low intensity bands at 716 and 747 cm-1. The series of Raman bands at 411, 439, 451 cm-1 and probably also the band at 500 cm-1 are assigned to the (VO-4) ν2 bending mode. The series of Raman bands at 293, 333 and 366 cm-1 are attributed to the (VO-4) ) ν4 bending modes. The ν3, ν3 and ν4 regions are complex for both minerals and this is attributed to symmetry reduction of the vanadate unit from Td to Cs.
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There is no doubt that place branding is a powerful and ubiquitous practice deployed around the globe. Parallel to its acceptance and development as a distinct discipline is an understanding that place branding as responsible practice offers the means to achieve widespread economic, social and cultural benefits. Drawing on work around place and identity in cultural geography and cultural studies, this paper engages critically with this vision. Specifically, it challenges the widely-held assumption that the relationship between place branding and place identity is fundamentally reflective, arguing instead that this relationship is inherently generative. This shift in perspective, explored in relation to current responsible place branding practice, is central to the realisation of place branding as a force for good.
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This paper considers constructions of institutional culture and power in the cover-up of child sexual abuse (CSA) by clergy in the Roman Catholic Church of Australia. The issue of cover-up has previously been considered in international inquiries as an institutional failing that has caused significant harm to victims of CSA by Catholic Clergy. Evidence given by select representatives of the Catholic Church in two government inquiries into institutional abuse carried out in Australia is considered here. This evidence suggests that, where cover-up has occurred, it has been reliant on the abuse of institutional power and resulted in direct emotional, psychological and spiritual harm to victims of abuse. Despite international recognition of cover-up as institutional abuse, evidence presented by Roman Catholic Representatives to the Victorian Inquiry denied there was an institutionalised cover-up. Responding to this evidence, this paper queries whether the primary foundation of cover-up conforms to the ‘bad apple theory’ in that it relates only to a few individuals, or the ‘bad barrel theory’ of institutional structure and culture.
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High power, high frequency pulsed electric fields known as pulsed power (PP) has been applied recently in biology and medicine. However, little attention has been paid to investigate the application of pulse power in musculoskeletal system and its possible effect on functional behavior and biomechanical properties of bone tissue. This paper presents the first research investigating whether or not PP can be applied safely on bone tissue as a stimuli and what will be the possible effect of these signals on the characteristics of cortical bone by comparing the mechanical properties of this type of bone pre and post expose to PP and in comparison with the control samples. A positive buck‑boost converter was applied to generate adjustable high voltage, high frequency pulses (up to 500 V and 10 kHz). The functional behavior of bone in response to pulse power excitation was elucidated by applying compressive loading until failure. The stiffness, failure stress (strength) and the total fracture energy (bone toughness) were determined as a measure of the main bone characteristics. Furthermore, an ultrasonic technique was applied to determine and comprise bone elasticity before and after pulse power stimulation. The elastic property of cortical bone samples appeared to remain unchanged following exposure to pulse power excitation for all three orthogonal directions obtained from ultrasonic technique and similarly from the compression test. Nevertheless, the compressive strength and toughness of bone samples were increased when they were exposed to 66 h of high power pulsed electromagnetic field compared to the control samples. As the toughness and the strength of the cortical bone tissue are directly associated with the quality and integrity of the collagen matrix whereas its stiffness is primarily related to bone mineral content these overall results may address that although, the pulse power stimulation can influence the arrangement or the quality of the collagen network causing the bone strength and toughness augmentation, it apparently did not affect the mineral phase of the cortical bone material. The results also confirmed that the indirect application of high power pulsed electric field at 500 V and 10 kHz through capacitive coupling method was safe and did not destroy the bone tissue construction.
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Biodiesel derived from microalgae is one of a suite of potential solutions to meet the increasing demand for a renewable, carbon-neutral energy source. However, there are numerous challenges that must be addressed before algae biodiesel can become commercially viable. These challenges include the economic feasibility of harvesting and dewatering the biomass and the extraction of lipids and their conversion into biodiesel. Therefore, it is essential to find a suitable extraction process given these processes presently contribute significantly to the total production costs which, at this stage, inhibit the ability of biodiesel to compete financially with petroleum diesel. This study focuses on pilot-scale (100 kg dried microalgae) solvent extraction of lipids from microalgae and subsequent transesterification to biodiesel. Three different solvents (hexane, isopropanol (IPA) and hexane + IPA (1:1)) were used with two different extraction methods (static and Soxhlet) at bench-scale to find the most suitable solvent extraction process for the pilot-scale. The Soxhlet method extracted only 4.2% more lipid compared to the static method. However, the fatty acid profiles of different extraction methods with different solvents are similar, suggesting that none of the solvents or extraction processes were biased for extraction of particular fatty acids. Considering the cost and availability of the solvents, hexane was chosen for pilot-scale extraction using static extraction. At pilot-scale the lipid yield was found to be 20.3% of total biomass which is 2.5% less than from bench scale. Extracted fatty acids were dominated by polyunsaturated fatty acids (PUFAs) (68.94±0.17%) including 47.7±0.43 and 17.86±0.42% being docosahexaenoic acid (DHA) (C22:6) and docosapentaenoic acid (DPA) (C22:5, ω-3), respectively. These high amounts of long chain poly unsaturated fatty acids are unique to some marine microalgae and protists and vary with environmental conditions, culture age and nutrient status, as well as with cultivation process. Calculated physical and chemical properties of density, viscosity of transesterified fatty acid methyl esters (FAMEs) were within the limits of the biodiesel standard specifications as per ASTM D6751-2012 and EN 14214. The calculated cetane number was, however, significantly lower (17.8~18.6) compared to ASTM D6751-2012 or EN 14214-specified minimal requirements. We conclude that the obtained microalgal biodiesel would likely only be suitable for blending with petroleum diesel to a maximum of 5 to 20%.
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In this paper we provide an overview of a number of fundamental reasoning formalisms in artificial intelligence which can and have been used in modelling legal reasoning. We describe deduction, induction and analogical reasoning formalisms, and show how they can be used separately to model legal reasoning. We argue that these formalisms can be used together to model legal reasoning more accurately, and describe a number of attempts to integrate the approaches.
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A cDNA encoding the chloroplast/mitochondrial form of glutathione reductase (GR:EC 1,6,4,2) from pea (Pisum sativum L.) was used to map a single GR locus, named GORI. In two domesticated genotypes of pea (cv, Birte and JI 399) it is likely that the GORI locus contains a single gene. However, in a semi-domesticated land race of pea sequences were detected but closely related sets of GR gene sequences were in JI 281 represent either a second intact gene or a partial or pseudogene copy. A GR gene was cloned from ev. Birte, sequenced and its structure analysed. No features of the transcription or structure of the gene suggested a mechanism for generating any more than one form of . From these data plus previously published biochemical evidence was suggested a second, distinct gene encoding for the cytosolic form of GR should be present in peas. The GORI-encoded GR mRNA can be detected in all main organs of the plant and no alternative spliced species was present which could perhaps account for the generation of multiple isoforms of GR. The mismatch between the number of charge-separable isoforms in pea and the proposed number suggests that different GR isoforms arise by some form of post-transnational modification.
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Importance Active video games may offer an effective strategy to increase physical activity in overweight and obese children. However, the specific effects of active gaming when delivered within the context of a pediatric weight management program are unknown. Objective To evaluate the effects of active video gaming on physical activity and weight loss in children participating in an evidence-based weight management program delivered in the community. Design, Setting, and Participants Group-randomized clinical trial conducted during a 16-week period in YMCAs and schools located in Massachusetts, Rhode Island, and Texas. Seventy-five overweight or obese children (41 girls [55%], 34 whites [45%], 20 Hispanics [27%], and 17 blacks [23%]) enrolled in a community-based pediatric weight management program. Mean (SD) age of the participants was 10.0 (1.7) years; body mass index (BMI) z score, 2.15 (0.40); and percentage overweight from the median BMI for age and sex, 64.3% (19.9%). Interventions All participants received a comprehensive family-based pediatric weight management program (JOIN for ME). Participants in the program and active gaming group received hardware consisting of a game console and motion capture device and 1 active game at their second treatment session and a second game in week 9 of the program. Participants in the program-only group were given the hardware and 2 games at the completion of the 16-week program. Main Outcomes and Measures Objectively measured daily moderate-to-vigorous and vigorous physical activity, percentage overweight, and BMI z score. Results Participants in the program and active gaming group exhibited significant increases in moderate-to-vigorous (mean [SD], 7.4 [2.7] min/d) and vigorous (2.8 [0.9] min/d) physical activity at week 16 (P < .05). In the program-only group, a decline or no change was observed in the moderate-to-vigorous (mean [SD] net difference, 8.0 [3.8] min/d; P = .04) and vigorous (3.1 [1.3] min/d; P = .02) physical activity. Participants in both groups exhibited significant reductions in percentage overweight and BMI z scores at week 16. However, the program and active gaming group exhibited significantly greater reductions in percentage overweight (mean [SD], −10.9% [1.6%] vs −5.5% [1.5%]; P = .02) and BMI z score (−0.25 [0.03] vs −0.11 [0.03]; P < .001). Conclusions and Relevance Incorporating active video gaming into an evidence-based pediatric weight management program has positive effects on physical activity and relative weight.
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During invasion and metastasis, cancer cells interact closely with the extracellular matrix molecules by attachment, degradation, and migration. We demonstrated previously the local degradation of fluorescently labeled gelatin matrix by cancer cells at invasive membrane protrusions, called invadopodia. Using the newly developed quantitative fluorescence-activated cell sorting-phagocytosis assay and image analysis of localized degradation of fluorescently labeled matrix, we document here that degradation and site- specific removal of cross-linked gelatin matrix is correlated with the extent of phagocytosis in human breast cancer cells. A higher phagocytic capacity is generally associated with increasing invasiveness, documented in other invasion and motility assays as well. Gelatin phagocytosis is time and cell density dependent, and it is mediated by the actin cytoskeleton. Most of the intracellular gelatin is routed to actively acidified vesicles, as demonstrated by the fluorescent colocalization of gelatin with acidic vesicles, indicating the intracellular degradation of the phagocytosed matrix in lysosomes. We show here that normal intracellular routing is blocked after treatment with acidification inhibitors. In addition, the need for partial proteolytic degradation of the matrix prior to phagocytosis is demonstrated by the inhibition of gelatin phagocytosis with different serine and metalloproteinase inhibitors and its stimulation by conditioned medium containing the matrix metalloproteinases MMP-2 and MMP-9. Our results demonstrate that phagocytosis of extracellular matrix is an inherent feature of breast tumor cells that correlates with and may even directly contribute to their invasive capacity. This assay is useful for screening and evaluating potential anti-invasive agents because it is fast, reproducible, and versatile.
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The life history strategies of massive Porites corals make them a valuable resource not only as key providers of reef structure, but also as recorders of past environmental change. Yet recent documented evidence of an unprecedented increase in the frequency of mortality in Porites warrants investigation into the history of mortality and associated drivers. To achieve this, both an accurate chronology and an understanding of the life history strategies of Porites are necessary. Sixty-two individual Uranium–Thorium (U–Th) dates from 50 dead massive Porites colonies from the central inshore region of the Great Barrier Reef (GBR) revealed the timing of mortality to have occurred predominantly over two main periods from 1989.2 ± 4.1 to 2001.4 ± 4.1, and from 2006.4 ± 1.8 to 2008.4 ± 2.2 A.D., with a small number of colonies dating earlier. Overall, the peak ages of mortality are significantly correlated with maximum sea-surface temperature anomalies. Despite potential sampling bias, the frequency of mortality increased dramatically post-1980. These observations are similar to the results reported for the Southern South China Sea. High resolution measurements of Sr/Ca and Mg/Ca obtained from a well preserved sample that died in 1994.6 ± 2.3 revealed that the time of death occurred at the peak of sea surface temperatures (SST) during the austral summer. In contrast, Sr/Ca and Mg/Ca analysis in two colonies dated to 2006.9 ± 3.0 and 2008.3 ± 2.0, suggest that both died after the austral winter. An increase in Sr/Ca ratios and the presence of low Mg-calcite cements (as determined by SEM and elemental ratio analysis) in one of the colonies was attributed to stressful conditions that may have persisted for some time prior to mortality. For both colonies, however, the timing of mortality coincides with the 4th and 6th largest flood events reported for the Burdekin River in the past 60 years, implying that factors associated with terrestrial runoff may have been responsible for mortality. Our results show that a combination of U–Th and elemental ratio geochemistry can potentially be used to precisely and accurately determine the timing and season of mortality in modern massive Porites corals. For reefs where long-term monitoring data are absent, the ability to reconstruct historical events in coral communities may prove useful to reef managers by providing some baseline knowledge on disturbance history and associated drivers.
A smoking cessation intervention for people with chronic Hepatitis C : a randomised controlled trial
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Purpose The purpose of this study was to examine the validity of current practice in smoking cessation for the general population i.e., a telephone counselling and nicotine replacement therapy (NRT) intervention and its applicability to people with chronic hepatitis-C. Methods A randomised controlled trial was conducted over twelve weeks. Following consent, ninety-two smokers (outpatients) with chronic hepatitis-C were recruited by the Nurse Practitioner hepatology, randomly assigned and stratified by number of cigarettes smoked (i.e., 15 and greater; <15) into the intervention group (telephone counselling and NRT) and control group (telephone counselling). Outcomes measured included socio-demographics, nicotine dependence, depression, anxiety and stress and quality of life (QOL). All statistical data were analysed using SPSS. Results After 12 weeks, the intervention group showed a sustained reduction of smoking i.e., 5.8(CI: 2.4,9.3) cigarettes less per day, whereas the control group showed 1.6(CI:-1.9,5.2) cigarette reduction. Although not statistically significantly different (F=2.9, p=0.090) the intervention group on average smoked 4.2 fewer cigarettes compared to the control group. After twelve weeks, seven patients in the intervention group and three patients in the control group reported quitting. Whilst not statistically significant (Fisher’s Exact, p=0.311) this was a clinically significant result. No differences were found for nicotine dependence or depression, anxiety and stress. The intervention group experienced no change in QOL (-0.1,CI:-0.9, 0.6), however, the environmental score for the control group decreased by 1.8(CI:1.0, 2.6,p= 0.001). This was statistically significant. Conclusion A telephone counselling and nicotine replacement therapy intervention from the nurse practitioner, hepatology reduced smoking in patients with chronic hepatitis-C. The intervention group showed a sustained reduction over the 12 weeks. A total of 10 patients quit smoking at the end of the study. QOL deteriorated in the environmental subscale for the control group. These results informed a nurse practitioner model of care for approaches to smoking cessation.