994 resultados para 7136-401


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Two recent studies of 9/11 literature are dismissive of the contributions that crime and espionage novels have made to ongoing efforts to map the significance of 9/11 and its aftermath. My essay contests the assumption that only literary fiction – which pays sufficient attention to trauma – can “bear witness” to the events of 9/11 and argues that such fiction is, in fact, singularly ill-equipped to illuminate the complex geo-political circumstances that 9/11 entrenched and transformed. By contrast, genre novels by John Le Carré and Don Winslow have responded in imaginative and critical ways to post-9/11 and avowedly trans-national securitization initiatives and hence to efforts to trouble traditional accounts of state sovereignty.

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Sudan dyes have been found to be added to chilli and chilli products for illegal colour enhancement purposes. Due to the possible carcinogenic effect, they are not authorized to be used in food in the European Union or the USA. However, over the last few years, many products imported from Asian and African countries have been reported via the Rapid Alert System for Food and Feed in the European Union to be contaminated with these dyes. In order to provide fast screening method for the detection of Sudan I (SI), which is the most widely abused member of Sudan dyes family, a unique (20 min without sample preparation) direct disequilibrium enzyme-linked immunosorbent assay (ELISA) was developed. The assay was based on polyclonal antibodies highly specific to SI. A novel, simple gel permeation chromatography clean-up method was developed to purify extracts from matrices containing high amounts of fat and natural pigments, without the need for a large dilution of the sample. The assay was validated according to the Commission Decision 2002/657/EC criteria. The detection capability was determined to be 15 ng g(-1) in sauces and 50 ng g(-1) in spices. The recoveries found ranged from 81% to 116% and inter- and intra-assay coefficients of variation from 6% to 20%. The assay was used to screen a range of products (85 samples) collected from different retail sources within and outside the European Union. Three samples were found to contain high amounts (1,649, 722 and 1,461 ng g(-1)) of SI by ELISA. These results were confirmed by liquid chromatography-tandem mass spectrometry method. The innovative procedure allows for the fast, sensitive and high throughput screening of different foodstuffs for the presence of the illegal colorant SI.

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Resonance Raman (RR) spectroscopy has been used to probe the interaction between dipyridophenazine (dppz) complexes of ruthenium(II), [Ru(L)(2)(dppz)](2+) (L = 1,10-phenanthroline (1) and 2,2-bipyridyl (2)), and calf-thymus DNA. Ground electronic state RR spectra at selected probe wavelengths reveal enhancement patterns which reflect perturbation of the dppz-centered electronic transitions in the UV-vis spectra in the presence of DNA. Comparison of the RR spectra recorded of the short-lived MLCT excited states of both complexes in aqueous solution with those of the longer-lived states of the complexes in the DNA environment reveals changes to excited state modes, suggesting perturbation of electronic transitions of the dppz ligand in the excited state as a result of intercalation. The most prominent feature, at 1526 cm(-1), appears in the spectra of both 1 and 2 and is a convenient marker band for intercalation. For 1, the excited state studies have been extended to the A and A enantiomers. The marker band appears at the same frequency for both but with different relative intensities. This is interpreted as reflecting the distinctive response of the enantiomers to the chiral environment of the DNA binding sites. The results, together with some analogous data for other potentially intercalating complexes, are considered in relation to the more general application of time-resolved RR spectroscopy for investigation of intercalative interactions of photoexcited metal complexes with DNA.

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Background
The identification of filamentous fungi and/or yeasts in the airway secretions of individuals with cystic fibrosis (CF) is becoming increasingly prevalent; yet the importance of these organisms in relation to underlying inflammation is poorly defined.

Methods
Cystic fibrosis bronchial epithelial cells (CFBE) and human bronchial epithelial cells (HBE) were co-incubated with Candida albicans whole cells or Aspergillus fumigatus conidia for 24 h prior to the measurement of pro-inflammatory cytokines IL-6 and IL-8 by ELISA.

Results
Treatment of HBE or CFBE with C. albicans whole cells did not alter cytokine secretion. However treatment of CFBE with A. fumigatus conidia resulted in a 1.45-fold increase in IL-6 and a 1.65-fold increase in IL-8 secretion in comparison to basal levels; in contrast there was far less secretion from HBE cells.

Conclusion
Our data indicate that A. fumigatus infection modulates a pro-inflammatory response in CF epithelial cells while C. albicans does not.

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The palaeoloricate ‘polyplacophorans’ are an extinct paraphyletic group of basal chiton-like organisms known primarily from their fossilized valves. Their phylo- genetic placement remains contentious, but they are likely to include both stem-group Polyplacophora and stem- group Aplacophora. Candidates for the latter position include ‘Helminthochiton’ thraivensis from the Ordovician of Scotland, which we redescribe here through a combined optical and micro-CT (XMT) restudy of the type material. The 11 specimens in the type series are all articulated, presenting partial or complete valve series as well as moul- dic preservation of the girdle armature; they demonstrate a vermiform body plan. The valves are typically palaeolori- cate in aspect, but differ in detail from all existing palaeol- oricate genera; we hence erect Phthipodochiton gen. nov. to contain the species. The most notable feature of the fossils is the spicular girdle; this is impersistently preserved, but demonstrably wraps entirely around the ventral surface of the animal, implying that a ‘true’ (i.e. polyplacophoran like) foot was absent, although we do not exclude the pos- sibility of a narrow solenogastre-like median pedal groove having been present. Phthipodochiton thraivensis presents an apparent mosaic of aplacophoran and polyplacophoran features and as such will inform our understanding of the relationship between these groups of extant molluscs. An inference may also be drawn that at least some other pal- aeoloricates possessed an ‘armoured aplacophoran’ body plan, in contrast to the ‘limpet-like’ body plan of extant Polyplacophora.

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We present a comprehensive study of the observational dependence of the mass-loss rate in stationary stellar winds of hot massive stars on the metal content of their atmospheres. The metal content of stars in the Magellanic Clouds is discussed, and a critical assessment is given of state-of-the-art mass-loss determinations of OB stars in these two satellite systems and the Milky-Way. Assuming a power-law dependence of mass loss on metal content,. M. Z(m), and adopting a theoretical relation between the terminal flow velocity and metal content, v(infinity). Z(0.13) (Leitherer et al. 1992, ApJ, 401, 596), we find m = 0.83 +/- 0.16 for non-clumped outflows from an analysis of the wind momentum luminosity relation (WLR) for stars more luminous than 105.2 L circle dot. Within the errors, this result is in agreement with the prediction m = 0.69 +/- 0.10 by Vink et al. (2001, A& A, 369, 574). Absolute empirical values for the mass loss, based on Ha and ultraviolet (UV) wind lines, are found to be a factor of two higher than predictions in this high luminosity regime. If this difference is attributed to inhomogeneities in the wind, and this clumping does not impact the predictions, this would imply that luminous O and early-B stars have clumping factors in their Ha and UV line forming regions of about a factor of four. For lower luminosity stars, the winds are so weak that their strengths can generally no longer be derived from optical spectral lines (essentially Ha) and one must currently rely on the analysis of UV lines. We confirm that in this low-luminosity domain the observed Galactic WLR is found to be much steeper than expected from theory (although the specific sample is rather small), leading to a discrepancy between UV mass-loss rates and the predictions by a factor 100 at luminosities of L similar to 10(4.75) L circle dot, the origin of which is unknown. We emphasize that even if the current mass-loss rates of hot luminous stars would turn out to be overestimated as a result of wind clumping, but the degree of clumping would be rather independent of metallicity, the scalings derived in this study are expected to remain correct.

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The role of net charge (Z) of thiols in their ability to radioprotect cells has been investigated in a glutathione (GSH)-deficient strain of E. coli. This strain, 7, is deficient in the enzyme gamma-glutamylcysteine synthetase and allows the effects of added low molecular weight thiols to be studied. Using the gas explosion system it is possible to measure the chemical repair of the free-radical precursors of lethal lesions by thiols in intact cells. The first-order chemical repair rate in strain 7 is 280s(-1) in comparison with 1100s(-1) in the wild-type strain 1157. From the measured difference in the intracellular concentration of GSH between the wild-type and the mutant, this gives a second-order repair rate, k(r)'s of 1.23 +/- 0.3 X 10(5) dm(3)mol(-1)s(-1). Measurement of intracellular thiol levels after addition of various low molecular weight thiols showed that uptake was rapid, leading to stable thiol levels within 1 min. The ratios of the intracellular to extracellular concentrations (C-in/C-out) were 0.74 for 3-mercaptopropionic acid (Z=-1), 0.56 for 2-mercaptoethanol (Z=0), 1.47 for cysteamine (Z=+1) and 1.04 for WR1065 (Z=+2). The k(r)'s for these thiols were 1.3 +/- 0.5 X 10(5) dm(3)mol(-1)s(-1) for 30-mercaptopropionic acid, 3.3 +/- 1.6 x 10(5) dm(3)mol(-1)s(-1) for 2-mercaptoethanol, 3.9 +/- 1.1 X 10(5) dm(3)mol(-1)s(-1) for cysteamine and 2.7 +/- 1.1 X 10(6) dm(3)mol(-1)s(-1) for WR1065. These are lower and increase less with charge than previously published values for chemical repair in isolated pBR322 DNA, probably because of the association of nucleoproteins and polyamines with the cellular DNA of E. coli. However, the approximate three-fold increase in k(r) per unit increase in Z shows that the counter-ion condensation and co-ion depletion are important in determining the effectiveness of charged thiols in the radioprotection of E. coli.

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The effects of each of the known platyhelminth neuropeptides were determined on muscle-strip preparations from the liver fluke, Fasciola hepatica. The activity of synthetic replicates of the C-terminal nonapeptide of neuropeptide F (NPF9, Moniezia expansa), and the FMRFamide-related peptides (FaRPs), GNFFRFamide, RYIRFamide, GYIRFamide and YIRFamide, were examined. Muscle-strip activity was recorded from 1 mm segments of muscle prepared from 28 to 32-day-old worms, using a photo-optic transducer system. None of the peptides (less than or equal to 10 mu M) altered baseline tension significantly; however, each of the peptides increased the amplitude and frequency of muscle contraction. The threshold for activity of each of the peptides examined was, respectively, 1 nM (RYIRFamide), 0.3 mu M (GYIRFamide and YIRFamide), and 10 mu M (GNFFRFamide and NPF9). All of the effects were reversible and repeatable, following wash-out. Muscle-strip integrity was tested following experimentation, using arecoline (10 mu M) and high-K+ bathing medium (90 mM K+).

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This paper and its companion paper describe the comparison between a one-dimensional theoretical model of a hydrogen discharge in a magnetic multipole plasma source and experimental measurements of the plasma parameters. The discharge chamber, described here, has been designed to produce significant densities of H- ions by incorporating a weak transverse field through the discharge to obtain electron cooling so as to maximize H- production. Langmuir probes are used to monitor the plasma, determining the ion density, the electron density and temperature and the plasma potential. The negative density is measured by photo-detachment of the extra electron using an intense laser beam. The model, described in the companion paper, uses the presented source geometry to calculate these plasma quantities as a function of the major are parameters; namely the are current and voltage and gas pressure. Good agreement is obtained between theory and experiment as a function of position and arc parameters.

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Age-related macular degeneration (AMD), is the leading cause of blind registration in the Western World among individuals 65 years or older. Early AMD, a clinical state without overt functional loss, is said to be present clinically when yellowish deposits known as drusen and/or alterations of fundus pigmentation are seen in the macular retina. Although the etiopathogenesis of AMD remains uncertain, there is a growing body of evidence in support of the view that cumulative oxidative damage plays a causal role. Appropriate dietary antioxidant supplementation is likely to be beneficial in maintaining visual function in patients with AMD, and preventing or delaying the progression of early AMD to late AMD. The Carotenoids in Age-Related Maculopathy (CARMA) Study is a randomized and double-masked clinical trial of antioxidant supplementation versus placebo in 433 participants with either early AMD features of sufficient severity in at least one eye or any level of AMD in one eye with late AMD (neovascular AMD or central geographic atrophy) in the fellow eye. The aim of the CARMA Study is to investigate whether lutein and zeaxanthin, in combination with co-antioxidants (vitamin C, E, and zinc), has a beneficial effect on visual function and/or prevention of progression from early to late stages of disease. The primary outcome is improved or preserved distance visual acuity at 12 months. Secondary outcomes include improved or preserved interferometric acuity, contrast sensitivity, shape discrimination ability, and change in AMD severity as monitored by fundus photography. This article outlines the CARMA Study design and methodology, including its rationale.

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Age-related maculopathy (ARM) is a common clinical entity. The late-stage manifestations of ARM, which are known as age-related macular degeneration (AMD), have devastating consequences for vision. Various risk factors have been identified in the development of the condition, which are consistent with the premise that oxidative stress plays an important role in its pathogenesis. Thus, the possibility that antioxidant balance can be manipulated through diet or supplementation has created much interest. Associations between diet and nutrition and the clinical features of ARM have been described. Scrutiny of the literature shows consistency in the report of notable reductions in serum micronutrients in wet AMD, however, the evidence for causation is still circumstantial. In this comprehensive review of the clinical literature, we have assessed the evidence for a link between diet and nutrition as risk factors for the development of ARM and AMD. All published case control, population-based, and interventional studies on ARM were examined. Although initial support appeared to be moderate and somewhat contradictory, the evidence that lifetime oxidative stress plays an important role in the development of ARM is now compelling. The positive outcomes in the Age-Related Eye Diseases Study, a major controlled clinical trial, have given hope that modulation of the antioxidant balance through supplementation can help prevent progression of ARM to AMD.

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There is a growing body of research regarding children and young people in state care that is organised around the concept of transition. Focusing mainly on young people leaving care, the research highlights their experiences of multiple transitions that can contribute to poor long-term outcomes in terms of emotional and psychological well-being, educational attainment and employment prospects. The smaller body of research that focuses on young children shows that their journeys before and when in state care are also marked by multiple and fragmented transitions. Despite the growing knowledge base, there are two areas that remain under-developed—research that draws attention to the lived experiences of young children regarding their transitions into state care; and the development of conceptual frameworks that centralise young children's perspectives to support the development of practice. This article begins to address these gaps by applying Schlossberg's transition framework to a case study of a young child regarding their transition into state care. The article highlights, through the child's perspectives, the multiple impacts of the transition and considers the implications for the development of better child-centred practice.

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OBJECTIVES: To assess the variation in practice of Barrett's esophagus (BE) management in comparison with accepted international guidelines before and after the introduction of a large BE randomized controlled trial (RCT) with protocols including those of tissue sampling.
DESIGN: A validated anonymized questionnaire was sent to 401 senior attending gastroenterologists asking for details of their current management of BE, especially histological sampling. Of the 228 respondents, 57 individuals (each from a different center) were in the first group to enter the ASPirin Esomeprazole (BE) Chemoprevention Trial (AspECT), and we assessed change in practice in these centers.
RESULTS: Ninety percent of specialists did not take adequate biopsies for histological diagnosis. Furthermore, 74% would consider aggressive surgical resection for prevalent cases of high-grade dysplasia in BE as their first-line choice despite the associated perioperative mortality. Ninety-two percent claim their lack of adherence to guidelines is because there is a need for stronger evidence for surveillance and medical interventions. Effect of the AspECT trial: Those clinicians in centers where the AspECT trial has started have improved adherence to ACG guidelines compared with their previous practice (P < 0.05). BE patients now get 18.8% more biopsies compared with previous practice, and 37.7% if the patient is entered into the AspECT trial (P < 0.01).
CONCLUSIONS: This large study indicates both wide variation in practice and poor compliance with guidelines. Because optimal histology is arguably the most important facet of BE management, the improvement in practice in centers taking part in the AspECT trial indicates an additional value of large international RCTs.

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Reviews of the literature have consistently highlighted significant gaps with regard to research associated with family caregivers within the context of palliative care. We sought to determine a priority driven research agenda for this field of inquiry.