992 resultados para Anti-resonance


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Pyrite and chalcopyrite mineral samples from Mangampet barite mine, Kadapa, Andhra Pradesh, India are used in the present study. XRD data indicate that the pyrite mineral has a face centered cubic lattice structure with lattice constant 5.4179 Å. Also it possesses an average particle size of 91.9 nm. An EPR study on the powdered samples confirms the presence of iron in pyrite and iron and Mn(II) in chalcopyrite. The optical absorption spectrum of chalcopyrite indicates presence of copper which is in a distorted octahedral environment. NIR results confirm the presence of water fundamentals and Raman spectrum reveals the presence of water and sulfate ions.

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Background: Hyperpolarised helium MRI (He3 MRI) is a new technique that enables imaging of the air distribution within the lungs. This allows accurate determination of the ventilation distribution in vivo. The technique has the disadvantages of requiring an expensive helium isotope, complex apparatus and moving the patient to a compatible MRI scanner. Electrical impedance tomography (EIT) a non-invasive bedside technique that allows constant monitoring of lung impedance, which is dependent on changes in air space capacity in the lung. We have used He3MRI measurements of ventilation distribution as the gold standard for assessment of EIT. Methods: Seven rats were ventilated in supine, prone, left and right lateral position with 70% helium/30% oxygen for EIT measurements and pure helium for He3 MRI. The same ventilator and settings were used for both measurements. Image dimensions, geometric centre and global in homogeneity index were calculated. Results: EIT images were smaller and of lower resolution and contained less anatomical detail than those from He3 MRI. However, both methods could measure positional induced changes in lung ventilation, as assessed by the geometric centre. The global in homogeneity index were comparable between the techniques. Conclusion: EIT is a suitable technique for monitoring ventilation distribution and inhomgeneity as assessed by comparison with He3 MRI.

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Context: Anti-Müllerian hormone (AMH) concentration reflects ovarian aging and is argued to be a useful predictor of age at menopause (AMP). It is hypothesized that AMH falling below a critical threshold corresponds to follicle depletion, which results in menopause. With this threshold, theoretical predictions of AMP can be made. Comparisons of such predictions with observed AMP from population studies support the role for AMH as a forecaster of menopause. Objective: The objective of the study was to investigate whether previous relationships between AMH and AMP are valid using a much larger data set. Setting: AMH was measured in 27 563 women attending fertility clinics. Study Design: From these data a model of age-related AMH change was constructed using a robust regression analysis. Data on AMP from subfertile women were obtained from the population-based Prospect-European Prospective Investigation into Cancer and Nutrition (Prospect- EPIC) cohort (n � 2249). By constructing a probability distribution of age at which AMH falls below a critical threshold and fitting this to Prospect-EPIC menopausal age data using maximum likelihood, such a threshold was estimated. Main Outcome: The main outcome was conformity between observed and predicted AMP. Results: To get a distribution of AMH-predicted AMP that fit the Prospect-EPIC data, we found the critical AMH threshold should vary among women in such a way that women with low age-specific AMH would have lower thresholds, whereas women with high age-specific AMH would have higher thresholds (mean 0.075 ng/mL; interquartile range 0.038–0.15 ng/mL). Such a varying AMH threshold for menopause is a novel and biologically plausible finding. AMH became undetectable (�0.2 ng/mL) approximately 5 years before the occurrence of menopause, in line with a previous report. Conclusions: The conformity of the observed and predicted distributions of AMP supports the hypothesis that declining population averages of AMH are associated with menopause, making AMH an excellent candidate biomarker for AMP prediction. Further research will help establish the accuracy of AMH levels to predict AMP within individuals.

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This thematic issue on education and the politics of becoming focuses on how a Multiple Literacies Theory (MLT) plugs into practice in education. MLT does this by creating an assemblage between discourse, text, resonance and sensations. What does this produce? Becoming AND how one might live are the product of an assemblage (May, 2005; Semetsky, 2003). In this paper, MLT is the approach that explores the connection between educational theory and practice through the lens of an empirical study of multilingual children acquiring multiple writing systems simultaneously. The introduction explicates discourse, text, resonance, sensation and becoming. The second section introduces certain Deleuzian concepts that plug into MLT. The third section serves as an introduction to MLT. The fourth section is devoted to the study by way of a rhizoanalysis. Finally, drawing on the concept of the rhizome, this article exits with potential lines of flight opened by MLT. These are becomings which highlight the significance of this work in terms of transforming not only how literacies are conceptualized, especially in minority language contexts, but also how one might live.

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We used Magnetic Resonance microimaging (μMRI) to study the compressive behaviour of synthetic elastin. Compression-induced changes in the elastin sample were quantified using longitudinal and transverse spin relaxation rates (R1 and R2, respectively). Spatially-resolved maps of each spin relaxation rate were obtained, allowing the heterogeneous texture of the sample to be observed with and without compression. Compression resulted in an increase of both the mean R1 and the mean R2, but most of this increase was due to sub-locations that exhibited relatively low R1 and R2 in the uncompressed state. This behaviour can be described by differential compression, where local domains in the hydrogel with a relatively low biopolymer content compress more than those with a relatively high biopolymer content.

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Classical architecture has a long history of representing the idealized proportions of the human body, derived from the Vitruvian man. This association with the idealized human form has also associated architecture as symbiotic with prevailing power structures. Meaning that architecture is always loaded with some signification, it creates a highly inscribed space. In the absence of architecture space is not necessarily without inscription, for within the void there can exist an anti-architecture. Like the black box theatre, it is both empty and full at the same time, in the absence of the architecture, the void of space and how it is occupied becomes much more profound. As Dorita Hannah writes, ‘In denying a purely visual apprehension of built space, and suggesting a profound interiority, the black-box posits a new way of regarding the body in space.’ This paper analyses the work of Harold Pinter and his use of the body to create an anti-architecture to subvert oppressors and power structures. Pinter’s works are an important case study in this research due to their political nature. His works are also heavily tied to territory, which bound the works in a dependent relationship with a simulated ‘place’. In the citation accompanying the playwright’s Nobel Laureate it states, '...in his plays [he] uncovers the precipice under everyday prattle and forces entry into oppression's closed rooms.' In Pinter’s work oppression manifests itself in the representation of a room, the architecture, which is the cause of a power struggle when objectified and defeated when subjectified. The following work examines how Pinter uses the body to subjectify and represent architecture as authority in his earlier works, which relied on detailed mimetic sets of domestic rooms, and then in his later political works, that were freed of representational scenography. This paper will also look at the adaption of Pinter’s work by the Belarus Free Theatre in their 2008 production of ‘Being Harold Pinter.’ The work of Pinter and the Belarus Free Theatre are concerned with authoritarian political structures. That is, political structures that works against ideas of individualism, ascribing to a mass-produced body as an artifact of dictatorship and conservatism. The focus on the body in space on an empty stage draws attention to the individual – the body amongst scenography can become merely another prop, lost in the borders and boundaries the scenery dictates. Through an analysis of selected works by Harold Pinter and their interpretations, this paper examines this paradox of emptiness and fullness through the body as anti-architecture in performance.

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Young male drivers are over-represented in road-related fatalities. Speeding represents a pervasive and significant contributor to road trauma. Anti-speeding messages represent a long-standing strategy aimed at discouraging drivers from speeding. These messages, however, have not always achieved their persuasive objectives which may be due, in part, to them not always targeting the most salient beliefs underpinning the speeding behavior of particular driver groups. The current study elicited key beliefs underpinning speeding behavior as well as strategies used to avoid speeding, using a well-validated belief-based model, the Theory of Planned Behavior and in-depth qualitative methods. To obtain the most comprehensive understanding about the salient beliefs and strategies of young male drivers, how such beliefs and strategies compared with those of drivers of varying ages and gender, was also explored. Overall, 75 males and females (aged 17-25 or 30-55 years) participated in group discussions. The findings revealed beliefs that were particularly relevant to young males and that would likely represent key foci for developing message content. For instance, the need to feel in control and the desire to experience positive affect when driving were salient advantages; while infringements were a salient disadvantage and, in particular, the loss of points and the implications associated with potential licence loss as opposed to the monetary (fine) loss (behavioral beliefs). For normative influences, young males appeared to hold notable misperceptions (compared with other drivers, such as young females); for instance, young males believed that females/girlfriends were impressed by their speeding. In the case of control beliefs, the findings revealed low perceptions of control with respect to being able to not speed and a belief that something “extraordinary” would need to happen for a young male driver to lose control of their vehicle while speeding. The practical implications of the findings, in terms of providing suggestions for devising the content of anti-speeding messages, are discussed.

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This paper assesses the capacity to provide semipermeability of the synthetic layer of surface-active phospholipids created to replace the depleted surface amorphous layer of articular cartilage. The surfaces of articular cartilage specimens in normal, delipidized, and relipidized conditions following incubation in dipalmitoyl-phosphatidylcholine and palmitoyl-oleoyl-phosphatidylcholine components of the joint lipid mixture were characterized nanoscopically with the atomic force microscope and also imaged as deuterium oxide (D2O) diffused transiently through these surfaces in a magnetic resonance imaging enclosure. The MR images were then used to determine the apparent diffusion coefficients in a purpose-built MATLAB®-based algorithm. Our results revealed that all surfaces were permeable to D2O, but that there was a significant difference in the semipermeability of the surfaces under the different conditions, relative to the apparent diffusion coefficients. Based on the results and observations, it can be concluded that the synthetic lipid that is deposited to replace the depleted SAL of articular cartilage is capable of inducing some level of semipermeability.

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With the increasing enrolment of students with disabilities in primary schools and the enactment of legislative protections for students with disabilities in Disability Discrimination legislation and the Disability Standards for Education, this study examines the experiences of parents of students with disabilities in Queensland State schools. This study is concerned with the experiences that parents of children with disabilities have in relation to the concept and processes of inclusive classroom practice within the primary school. The experiences of parents in large metropolitan schools in Queensland, Australia are analysed in light of current anti-discrimination legislation operating within Australia. Data were collected using a mixed methodology in which 50 parents from nine large metropolitan Queensland State schools responded to a Parent Questionnaire about their experiences in their child’s school. This was followed by two focus groups with a total of six parents who described their experiences in their child’s school. Together the qualitative and quantitative information complemented the other to provide a unique perspective on the impact of anti-discrimination legislation. The findings from the study suggest that parents and their children continue to be discriminated against and that the legislation and associated standards have not eliminated this discrimination. Recommendations are made in the final chapter that propose an inclusive schooling framework for students with disabilities. This intends to ensure not only compliance with the ‘spirit’ of Anti-Discrimination legislation and the Disability Standards, but also a means by which schools may evolve to become inclusive and embracing of difference as part of overall richness of schools as opposed to deficiency.

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Sodium and cesium mordenite (denoted NaM and CsM, respectively) were investigated as potential catalysts for the synthesis of polyacetylene ((CH) x). Both were successful in initiating polymerization of purified gaseous acetylene at room temperature as evidenced by Raman spectroscopic studies. The polyacetylene synthesised in this way exhibited resonance enhancement of the polyene skeletal vibrations. trans-Polyacetylene, but no cis-(CH) x, was detected. As no apparent coloration of the NaM and CsM substrates accompanied the formation of trans-(CH) x it was concluded that only small quantities of the polymer were present. The number of conjugated double bonds was estimated from the frequencies of the Raman active C-C and C=C stretching vibrations, and it was shown that the trans-(CH) x formed on CsM has a distribution of conjugation lengths ranging from less than 6 to at least 30 double bonds. The polyacetylene formed on NaM was significantly shorter and was produced in lower yields than that synthesized on CsM. "Sliced" resonance excitation profiles of polyacetylene formed on CsM were obtained using nearly 40 different excitation wavelengths and these confirmed that the adsorbed trans-(CH) x was composed of segments having a distribution of conjugated lengths. The architecture of the mordenite pore system permitted only a single polymer molecule per channel, thereby preventing cross-linking. Raman spectroscopic studies of the effects of exposure to air revealed that progressive oxidative degradation occurred with a reduction in the number of conjugated double bond

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Infusions and decoctions of Cymbopogon ambiguus have been used traditionally in Australia for the treatment of headache, chest infections and muscle cramps. The aim of the present study was to screen and identify bioactive compounds from C. ambiguus that could explain this plant's anti-headache activity. A dichloromethane extract of C. ambiguus was identified as having activity in adenosine-diphosphate-induced human platelet aggregation and serotonin-release inhibition bioassays. Subsequent fractionation of this extract led to the isolation of four phenylpropenoids, eugenol, elemicin, Eugenol methylether and trans-isoelemicin. While both Eugenol and elemicin exhibited dose-dependent inhibition of ADP-induced human platelet serotonin release, only eugenol displayed potent inhibitory activity with an IC(50) value of 46.6 microM, in comparison to aspirin, with an IC(50) value of 46.1 microM. These findings provide evidence to support the therapeutic efficacy of C. ambiguus in the non-conventional treatment of Headache and Inflammatory conditions.

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Skin cancer is one of the most commonly occurring cancer types, with substantial social, physical, and financial burdens on both individuals and societies. Although the role of UV light in initiating skin cancer development has been well characterized, genetic studies continue to show that predisposing factors can influence an individual's susceptibility to skin cancer and response to treatment. In the future, it is hoped that genetic profiles, comprising a number of genetic markers collectively involved in skin cancer susceptibility and response to treatment or prognosis, will aid in more accurately informing practitioners' choices of treatment. Individualized treatment based on these profiles has the potential to increase the efficacy of treatments, saving both time and money for the patient by avoiding the need for extensive or repeated treatment. Increased treatment responses may in turn prevent recurrence of skin cancers, reducing the burden of this disease on society. Currently existing pharmacogenomic tests, such as those that assess variation in the metabolism of the anticancer drug fluorouracil, have the potential to reduce the toxic effects of anti-tumor drugs used in the treatment of non-melanoma skin cancer (NMSC) by determining individualized appropriate dosage. If the savings generated by reducing adverse events negate the costs of developing these tests, pharmacogenomic testing may increasingly inform personalized NMSC treatment.

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We assessed whether alternative transcripts (using KLK2, KLK3 and KLK4 as models) are differentially regulated by androgens and anti-androgens as an indicator of prostate cancers as they acquire treatment resistance. Using RNAseq of LNCaP cells treated with dihydrotestosterone, bicalutamide and enzalutamide, we show that the expression of variant KLK transcripts is markedly different to other variant transcripts at those loci. We also reveal that KLK variants are also over 2-fold more highly expressed in prostate cancers compared to their corresponding normal prostate. We propose that androgens and anti-androgens can activate specific variant transcripts of critical prostate cancer genes during treatment resistance

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The charge transfer-mediated surface enhanced Raman scattering (SERS) of crystal violet (CV) molecules that were chemically conjugated between partially polarized silver nanoparticles and optically smooth gold and silver substrates has been studied under off-resonant conditions. Tyrosine molecules were used as a reducing agent to convert silver ions into silver nanoparticles where oxidised tyrosine caps the silver nanoparticle surface with its semiquinone group. This binding through the quinone group facilitates charge transfer and results in partially oxidised silver. This establishes a chemical link between the silver nanoparticles and the CV molecules, where the positively charged central carbon of CV molecules can bind to the terminal carboxylate anion of the oxidised tyrosine molecules. After drop casting Ag nanoparticles bound with CV molecules it was found that the free terminal amine groups tend to bind with the underlying substrates. Significantly, only those CV molecules that were chemically conjugated between the partially polarised silver nanoparticles and the underlying gold or silver substrates were found to show SERS under off-resonant conditions. The importance of partial charge transfer at the nanoparticle/capping agent interface and the resultant conjugation of CV molecules to off resonant SERS effects was confirmed by using gold nanoparticles prepared in a similar manner. In this case the capping agent binds to the nanoparticle through the amine group which does not facilitate charge transfer from the gold nanoparticle and under these conditions SERS enhancement in the sandwich configuration was not observed.

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Speeding remains a pervasive road safety problem, increasing both crash frequency and severity. Advertising countermeasures which aim to change individuals’ attitudes and behaviours are a key component in the array of countermeasures aimed at reducing this risky behaviour. Enhancing individuals’ perceptions of the personal relevance of such messages is important for increasing persuasiveness. This study examined what males and females reported as the most concerning aspects associated with (i) receiving a speeding fine, (ii) losing one’s license, and (iii) being involved in a crash. For each of these outcomes, a range of specific and appropriate aspects were assessed. For instance, in relation to receiving a fine, individuals reported the extent to which they would, for example, feel concerned about losing demerit points and paying more in insurance premiums. An online survey of 751 drivers (579 males; 16-79 years) was administered. When controlling for age, overall significant gender differences were found in relation to two of the three outcomes; receiving a fine and being in a crash. Follow-up tests of univariate effects revealed that females consistently reported being significantly more concerned than males on all aspects. Thus, for being fined, females were significantly more concerned with, for example, being caught and receiving a ticket in the mail; while, for being in a crash, specific aspects included, for example, injuring/killing oneself and seeing oneself as not a good/safe driver. The findings are discussed in terms of their implications for developing well-targeted messages aimed at discouraging drivers from speeding.